The prostate is a gland located retroperitoneal, situated at the neck of the bladder encircling the urethra and seminal vesicles and is devoid of a distinct margin. The prostate gland weighs approximately 20 grams (Moore & Agur., 2004). Its primary function is to produce seminal fluid, the medium in which sperm travels through the female reproductive system to fertilize the egg. The prostate is composed of both epithelial and stromal cells. The prostate can be divided into distinct zones; this system of division helps describes which area of the prostate is affected during the investigation process. The zones are as follows; central zone (CZ), peripheral zone (PZ), transitional zone (TZ) and the peri-urethral zone as shown in Fig 1. It is important to note that the majority of carcinomas of the prostate arise in the peripheral zone (Kumar et al., 2004) as shown In Figure 1.
Inflammation of the prostate is known as Prostatitis. It can be subdivided into two distinct categories: acute bacterial prostatitis and chronic bacterial prostatitis, other categories include chronic abacterial prostatitis and granulomatous prostatitis.
Acute bacterial prostatitis usually occurs due to intraprostatic reflux of urine, where E-coli is present in the urine leading to the symptoms such as fevers, chill and dysuria (Kumar et al., 2004).
Chronic bacterial prostatitis usually occurs as a result of recurrent urinary tract infections. Chronic bacterial prostatitis symptoms include low back pain, dysuria and perineal and supra pubic discomfort (Kumar et al., 2004).
1.3.2. BENIGN PROSTATIC HYPERPLASIA OF THE PROSTATE
Benign prostatic hyperplasia (BPH), also known as nodular hyperplasia is the most common disease of the prostate. It can be seen in approximately 20% of men 40 years of age increasing to 70% by age 60 and 90% at age 70. Nodular hyperplasia has been described as 'a problem of enormous magnitude' effecting 30% of white Americans over 50 years of age (Kumar et al., 2004).
The development of BPH is due to the action of Dihydrotestosterone which is the primary chemical mediator responsible for the development of this disease. It principally acts by causing synthesis of the epithelial and stromal cells of the prostate. These cells synthesize/respond at different rates hence leading to the nodular presentation of the disease. Huge emphasis is placed on correct diagnosis at point of testing to prevent men suffering from BPH being mistaken for carcinoma of the prostate leading to unnecessarily morbidity.
1.3.3. TUMOURS OF THE PROSTATE
Adenocarcinoma is the most common form of cancer in men and the second most leading cause of cancer death. 2010 figures from the USA showed that 217,730 cases of cancer were detected of which nearly 32,050 were described as lethal (American Cancer Society 2010). The National Cancer Registry of Ireland suspects an increase in the number of men presenting with prostate cancer by approximately 275% by the year 2020 (National Cancer Registry of Ireland 2009). The cumulative risk of a man developing prostate cancer in Ireland before the age of 50 is 1 in 485 and before the age of 70 is 1 in 13 (Health Service Executive 2010). This highlights the importance of accurate prostate care in a health context.
1.3.4. PROSTATE CANCER: CAUSES AND RISK FACTORS
There are many suspected causes of prostate cancer; however no definitive consensus has been reached. Risk factors such as age, race, family history, hormonal influences and environmental factors are all suspected of playing a role in the development of the carcinoma of the prostate (Nelson et al., 2003 ) . A study undertaken by Ferris et al (2011) found that constitutional, and non-dietary environmental factors affect the incidence rate of prostate cancer in men. They concluded that much more study is required to discover the relevant variables. Racial differences have been extensively researched and it has been found that the disease is uncommon in Asians, Chinese and Japanese. The highest rate of incidence is among blacks men in the United States (Ekman, 1999). A study by Demark-Wahnefried et al showed that socio-economic barriers between white and black classes made a significant difference to early detection rates. Moses et al (2010) found that there were significant differences in primary treatment between these classes. The study showed categorically that blacks receive a lower standard of care and treatment. This may in some way explain as to why those of African American decent are less likely to request testing and treatment and therefore may present with later stage cancers.
1.3.5. CLASSIFICATION OF PROSTATE CANCER.
Classification of prostate neoplasms, can be either by their cellular differentiation or location, the majority of tumours (75%) arise in the peripheral zone, 15% in the transitional zone and 10% in the central zone (Bramley, 2004). Histologically they present as well- defined masses. Histology of the carcinoma is of extreme importance during the biopsy process.
Irish hospitals mainly use the Gleeson Grading System; low grade tumours are two and are usually slow-growing and less likely to spread. A score of between five and seven is moderate and high grade tumours are graded between eight and ten. Staging of the tumour describes its size and spread. T1 and T2 are located within the prostate. T3 and T4 have spread beyond the prostate.
1.4. CLINICAL PRESENTATION
Patients suffering from carcinoma of the prostate present with numerous symptoms characteristic of prostate carcinoma such as dysuria, nocturia and lower back pain. Dysuria is defined as a hesitancy or difficulty when urinating, a result of enlargement/synthesis of the tissue in the peri-urethral area of the prostate gland this consequently leads to compression of the urethra. Nocturia, a recurrent need to urinate at night, is present in many cases. Lower back pain which can be as a result of metastases of the carcinoma to the bone, prostatic metastases are predominately osteoblastic in nature.
1.5. DIAGNOSIS OF PROSTATE CARCINOMA
1.5.1 CURRENT GUIDELINES FOR THE DIAGNOSTIC PATHWAY
Currently, there are no set guidelines in the Republic of Ireland in the diagnosis of prostate cancer. The RCR, NICE and WHO guidelines are imported by individual hospitals to make an ad-hoc set of local rules. In 2009, a partnership between the NCCP and HSE provided guidelines to the general practitioners of Ireland to set out the requirements of referral in cases of suspected prostate cancer. These guidelines were limited to the tests required, the results at which referral was deemed necessary and did not include guidelines for individual radiography departments in receipt of referrals for testing by GP's.
Drummond et al found that factors prompting GP's to refer asymptomatic patients for PSA tests was prompted by a high level of support from doctors for the test combined with limited clinical experience and poor knowledge of the referral criteria. This study showed that there was a need for continued professional development with regards to the diagnosis and treatment of prostate cancer.
1.5.2. BIOMECHANICAL MARKERS
Prostate Specific Antigen (PSA) is the primary biomechanical marker used to test for the presence of prostate cancer. It has long been used in the diagnosis and management of prostate cancer (Gretzer et al, 2003). A level of over than 4ng/ml is said to be indicative of cancerous changes within the prostate. Contradicting these findings Thompson et al (2004) found that 15.2% of men with a PSA level of less than 4ng/ml had prostate cancer, leading to false negative results to the patient. Conversely, a separate study it was found that between 60 -75% with PSA levels of between 4.1 -9.9ng/ml who concurrently had biopsy did not have prostate cancer (Smith et al, 1997). Difficulty in definitively diagnosing a patient leads to unnecessary costs in the health care environment, increased unnecessary morbidity for patients undergoing unnecessary procedures.
1.5.3. TRANS-RECTAL ULTRASOUND
Trans-rectal Ultrasound also known as TRUS is often the tool used in the diagnosis of prostate cancer as it provides real-time imaging of the prostate. It involves scanning the prostate in the transverse plane thereby obtaining images from the prostate base to prostate apex. Prostate cancer is evident on ultrasound images by the visualization of a hypoechoic pattern. It is important to note that prostatitis and glandular atrophy all give rise to hypoechoic areas (Ozden et al, 2005). Ultrasound is useful as it is able to detect areas of abnormalities however the primary use of ultrasound is to undertake biopsy of the prostate. This involves the patient lying in the lateral decubitus position with their knees bent. The biopsy needle is advanced to the area under investigation providing the method of differential diagnosis of the hypoechoic lesions (Brawer 1989). The main disadvantage with trans-rectal ultrasound biopsy it that it can produce false negative results in approx. 20-40% of biopsies (10). A study conducted by Sauvain et al (2003) found that the sensitivity and specificity of ultrasound in the diagnosis of cancer was increased by 87.9% to 92.4% and 57.6% to 72% respectively when combined with Power Doppler Sonography. Power Doppler Sonography allows for visualisation of blood flow.
1.5.4. MAGNETIC RESONANCE IMAGING
MRI uses electromagnetic waves to produce images of excellent low contrast density. This proves highly useful in diagnosing pathologies of the prostate. Common indications for MRI of the prostate include abnormalities of the seminal vesicles, primary and secondary neoplastic changes, and infection and haemorrhage (Thompson et al 2004) (11). MRI of the prostate allows for visualizing the internal and substructure of the prostate. According to Coakley it's a "one-stop shop" for evaluation of the prostatic, peri-prostatic and pelvic anatomy. It is advantageous to other modalities as the wide range of pulse sequences allows for characterization of any abnormalities present. Disadvantages include hypersensitivity to motion artefact, patients can find the enclosed space of the magnetic bore intolerable. Also, haemorrhage can appear as abnormalities on MRI images and can be confused at the carcinoma. Lawrentschuk and Fleshner (?) proved that MRI can be used to great effect in patients with elevated PSA levels but previous negative biopsies in the diagnostic pathway. Magnetic Resonance Spectroscopy Imaging (MRSI) is also being evaluated which has been shown to play a useful role in patients with increased PSA levels and repeated negative biopsies (Tirwawi 2009). MRSI sometimes allows for the identification of neoplastic prostatic zones. While this has been shown by Lawrentschuk and Fleshner (?), additional studies are required to confirm that its reliability and significance to the diagnostic pathway. A combination of MRI and MRSI can have significant advantages over other methods because it reduces the numbers of repeated biopsy and therefore decreased morbidity on the patient (Amsellem-Ouazana et al). MRSI and contrast-enhanced MRI improves sensitivity and specificity of tumour detection. Overall MRI and MRSI have been shown to have accuracy similar to biopsy for intra-prostatic localisation of cancer and are more accurate in the prostate apex (Wefer et al.). The feasibility and safety of MRI in diagnosis is currently under investigation by a study titled the PROMIS study. This study is in its preparatory stage. The results of this trial, it is hoped, will give definitive answers on the scope that MRI and MRSI could potentially have in the area of prostate cancer diagnosis.
1.6. COMPARISON OF MAGNETIC RESONANCE IMAGING AND TRANSRECTAL ULTRASOUND OF THE PROSTATE (INCLUDING BIOPSY).
Both Ultrasound and MRI have biopsy availability and each carries its own inherent advantageous and disadvantages. Ultrasound Biopsy is readily available in comparison to MRI biopsy, less costly and easy to use. However 25% of patients who have prostate cancer can wrongly receive a false negative result with ultrasound. Complications include persistent haemoturia in 47.1% of patients and generally this lasts no longer than 7 days. Carroll et al., found the following incidence of adverse events;
Immediate Adverse Event
Overall Incidence (%)
Rectal Bleeding
8.3
Vasovagal Episodes
5.3
Haemoturia
70.8
Table: Immediate Adverse Events (Carroll, P. & Shinohara, K. (2004).
The patient should be counselled on these effects before undertaking the procedure.
Delayed Adverse Event
Overall Incidence (%)
Dysuria
9.1
Vague Pelvic Discomfort
13.2
Rectal Bleeding
9.1
Blood in the sperm
9.1%
Table: Delayed Adverse Events (Carroll, P. & Shinohara, K. (2004).
MRI is advantageous over ultrasound as it depicts the internal and external anatomy of the prostate well. It can show extrascapsular invasion or seminal vesicle invagination of prostate cancer while ultrasound is incapable of this. MRI biopsy is a relatively new tool and its availability is limited, this is primarily due to the cost involved (Carroll, P et al, 2005).
In the area of treatment, it is worth mentioning that real-time fusion of ultrasound and MRI images could facilitate MRI guided prostate cancer therapies such as brachytherapy, high focused ultrasound ablation or direct injection of therapeutic agents (Singh et al).
1.7. PROSTATE CANCER SCREENING IN IRELAND
Currently there is no national prostate cancer screening service in Ireland. The National Cancer Registry of Ireland (NCRI., 2007) aims to reduce cancer in Ireland and along with the National Cancer Control Programme have set up eight rapid access prostate cancer centres to help tackle the increased numbers presenting with suspected prostate cancer.
The introduction of a national prostate cancer screening service is a topical subject and a cost-benefit analysis is currently being investigated. Advantages of the introduction of a prostate cancer screening service would include reduced mortality rates and increased awareness among the male community. However disadvantages include increased costs on the health care system, over detection of cancers and increased morbidity on patients wrongly diagnosed. Djulbegovic et al (?) examined the evidence on the benefits and harms of prostate cancer screening. Using randomised controlled trials comparing screening by prostate specific antigen (PSA) with or without digital rectal examination versus no screening. It found no significant effect of screening on mortality from prostate cancer in a total of 387,286 participants from six RCT's. Quality of life and potential harms associated with screening were not discussed. Fritz et al in the European Randomised Study of Screening for Prostate Cancer (ERSPC) study involved 182,000 men in the age group 50-74years in seven countries. Half were offered PSA screening at an average of once every 4 years and the remainder were placed in the control group. A difference of 7.1 men per 10,000 was found (a 20% decrease). Nevertheless, it was associated with a higher risk of over diagnosis. The percentage decline in prostate cancer deaths found above increased when the results of the ERSPC study were compared to a control group in Northern Ireland where PSA is infrequent. The comparison found that a 37% decline in prostate cancer deaths was achievable.
Extrapolating the results of the ERSPC study, Draisma et al. (2009) estimated lead times and over-detection due to PSA screening. It estimated that PSA screening may advance diagnosis by at least 10 years. It estimated that screening (cut off of 3ng/ml and a four year interval) raised the lifetime risk of a prostate cancer diagnosis by 107% compared to Zappa et al. which estimated 65%-93% (at age 65 years). Etzioi et al. (2006) used a higher cut-off of 4ng/ml PSA level estimated over detection probabilities of 35% at a lead time of seven years. A trial involving 9,000 Swedish men who were followed up for 20 years, Sandholm et al (?) randomly selected some 1,500 men for prostate cancer screening every three years starting in 1987 with 7,500 acting as controls. All men with cancer diagnosed up to the end of 1999 were included in the analysis, with survival figures followed until 2008. It concluded that screening did not reduce deaths from the tumour and may cause both over-detection and over-treatment. The author concludes the "Before undergoing PSA testing, asymptomatic men should be informed about the potential hazards of treatment". A recent study by Ilic et al 2011 has shown that prostate cancer screening does not significantly decrease death from this cancer and that benefits could take approximately < 10 years to show results, so as a result men with a life expectancy of less than 10 to 15 years should be told that prostate cancer screening is not beneficial and has harms. Ilic et al (2007) could not draw a conclusive conclusion on the benefit versus risk of screening after a systematic review of the area. Sandholm et al (?) found that deaths from prostate cancer did not differ between men screened regularly and those that were not screened.
A study undertaken by Fitzpatrick et al (?) found that 94% of men believe that by regular screening one reduces their chances of developing prostate cancer. Active surveillance has been recommended by Klotz, L (2004, 2006 and 2010) as a middle ground. In taking this option, however, the possibility that those with aggressive forms of cancer may be undertreated has been muted.
1.8. SUMMARY
From the literature review, it is evident that ultrasound is used in the diagnosis of prostate cancer while MRI is primarily used for staging and grading of the pathology, as in line with the RCR guidelines, nonetheless, it must be noted that MRI is advantageous over ultrasound in a number of settings. This dissertation aims to investigate the current utilisation of imaging tools in Ireland in the diagnosis of prostate cancer, and to answer the question of whether or not there is a demand for MRI biopsy facilities in Ireland. The views of health care professionals working within Ireland will also be examined.
Prostate cancer screening is being investigated on a national and international level, to assess the risk-benefit analysis. The cost to the Exchequer of such a screening programme must also be analysed before a programme is implemented. No study has been published by any Irish body, stating the projected cost of rolling out a screening programme. Additionally, prostate cancer affects generally affects men in their 60's or 70's and therefore, these men would be of retirement age. Common sense dictates that the impact for the economy to lose a person of working age contributing taxes to the government is greater than that of one person who is retired from the workforce. The loss to the economy of morbidity and mortality in this age group is lower than that of morbidity or mortality in younger age groups. Factoring in this differential, it would make justification of a national screening programme more improbable especially as most studies investigating screening above have highlighted the possibility and, indeed, probability of over-detection.
CHAPTER 2. METHODOLOGY
2.1. LITERATURE REVIEW
Prior to commencement of the main study, a broad and detailed literature review was undertaken. This provided a theoretical background to the study and allowed the researcher to contextualise the study's findings in relation to the existing body of knowledge and redefines the methodology (Kumar, 2005). It provided the reference source from which questions for interviews were constructed. The literature review was compiled using information from databases such as Pubmed, Science Direct and Google Scholar using keywords such as prostate cancer, magnetic resonance imaging and ultrasound biopsy.
This literature review was aided by the construction of a mind-map which can be seen in Appendix A. The mind-map highlighted any areas of interest and what content should be included in the resultant study.
Resources used for reference were always checked for creditability and authenticity before entry into final proposal. Parameters for inclusion into the study were laid out before the literature review began. These parameters were a series of questions asked the investigator to ensure that the study fulfilled the requirements of the study as outlined below:
Author credibility: The integrity and possible bias of the author.
The study hypothesis: Clearly defined.
The study design: The population studied, interventions, valid and accurate measurements, outcomes etc.
The analysis of results: Accurate and relevant to the hypothesis
Inclusion of contrary studies: Does the study reference studies which have both agreed and disagreed with the study's results or is it slanted to supporting arguments.
In choosing the literature 'pool' from which the review was carried out, primary sources were deemed essential, however, peer-reviewed resources were also included for the compilation of a well-rounded review.
2.2. ETHICAL APPROVAL
Ethical Approval was obtained once permission was granted via a letter detailing that all interviews would be recorded for transcription purposes, it was strongly stated that all information would be dealt with confidentiality and confidence. It is important to note that all participants were allowed to withdraw at any time during the study.
Once individual informed consent was received from each interviewee ethical approval from each hospital was deemed unnecessary. It was also necessary to contact the radiology services manager in each hospital to request oral approval to undertake such a study. They were informed of the title, the time required and that their hospital would not be named the study. Confidentiality of the resultant interviews was maintained by using a coding system throughout e.g. Urologist A. All written data was held in encrypted files and the Dictaphone was erased once transcription was complete. A UCD ethics exemption form was completed in line with UCD guidelines as shown in Appendix B.
2.3. STUDY POPULATION AND SAMPLE SIZE
The population under investigation has to have the expertise and appropriate knowledge to answer the hypotheses of the proposed study, hence early on in the study it was deemed necessary to interview Consultant Urologist, Consultant Radiologists and Sonographers. On careful re-examination it was seen as unnecessary to interview sonographers as they were not as heavily involved in the patient care pathway as previously expected. As a result interviews took place with Consultant Urologists and Consultant Radiologists as they are the personnel involved in the diagnosis and treatment of prostate cancer. As with the case of this study it is always preferable to have the largest sample size to receive the best source of information (Somekn & Lewin 2005), due to time restraints of this undergraduate project and cost issues, it was deemed sufficient to interview three participants from each interview category to meet the research needs. The hospitals consisted of three cancer centres spread throughout Ireland.
2.4. PILOT STUDY
It was necessary to undertake a pilot study to ensure the method of data collection met the requirements of the study. The pilot study was undertaken with the first registered urologist in Ireland. The procedure for the pilot study was as follows: The interview was administered to the pilot subject in precisely the same wording, tone and order as it was planned for administration in the main study. Feedback was requested from the subject to identify ambiguities and difficult questions. All unnecessary, difficult or ambiguous questions were either deleted or re-worded.
Each question was assessed to ensure it allowed the subject an adequate range of responses. The spectrum of replies that could be given was assessed to ensure the minimum of replies could be interpreted in terms of the information that is required. The interview was revised until the researcher was satisfied that it is concise, relevant and unbiased (Peat et al, 2002).
Amendments were made to the questions on the advice received and all questions were re-piloted during the same interview as in line with guidelines laid out by (Oppenheim 2005). This improved the clarity of the questions (Silverman 2006).The pilot study proved useful as it also gave the opportunity for the inexperienced researcher to gain experience in their interview technique and to analyse their performance (Polit and Hungler, 1999, Marshall and Rossman, 1999). This is an important element of the research to ensure an appropriate rapport was achieved and maintained throughout the interviewing process. Neutrality of the questioning process was tested. The importance of neutrality is paramount. No bias on the part of the interviewer should be inferred by the style or tone of questioning. At times probes were deemed necessary to deepen the responses to the questions and increase the depth and richness of the responses (Patton, 2002). The pilot study highlighted where probes were necessary and how best to style the questions to achieve complete responses without the introduction of bias.
2.5. METHOD OF DATA COLLECTION
As stated prior the method of data collection was via interview technique, however due to the time restraints of this study, not all interviews were collected in person, Interviews with consultant radiologists were carried out by email and as a result the amount of raw data was reduced significantly hindering the study. Data was requested from each department on the cost of trans-rectal ultrasound scans and MRI scans and all departments were unwilling to provide this information. They suggested that the vendors should be contacted. However, after written and oral requests directed to specified vendors, no reply was received.
2.5.1 INTERVIEWS
Two Semi- Constructed interviews were composed and they consisted of two question types open and closed ended questions (Appendix C). This had the advantage of allowing the interviewee to expand where they felt necessary and though analysis of this data tends to be more difficult, the open-ended questions permits one to understand the world as seen by the respondents (Patton, 2002) and to 'tell it as they see it' (Denzin, 1978, Cohen et al,. 2007)
An interview guide was prepared to ensure that 'basic lines of inquiry were pursued with each person interviewed (Patton 2002). It helps the interviewer to use the limited time available to them appropriately (Patton 2002).The main reasons behind using the method of open- ended questions was that comparability of responses is made easier and facilitates organization and analysis of the raw date (Patton 2002).There was a broad mix of questions used throughout the interviews mixing background, feeling, knowledge and sensory questions to get a large overview and insight into the topic.
In the conducting of an interview based there are disadvantages, including, there is a risk that the interviewer may bias the responses given. In general, the author followed guidelines similar to those proposed by Williams, A:
Short questions: The author aimed for less than 25 words per question
Use the Gunning Fog Index: To calculate the reading age for each question, it was assume that the individuals being interviewed were of high intelligence, however, we believed that have a reading age of less than 20 years was important to ensure flow and rapport within the interview and also as an allowance to the novice interviewer
Gunning Fog Index Results:
Question
Gunning Fog Index (years)
In your department have you seen an increase or decrease in the number of men presenting to you with suspected prostate cancer?
10.62
Why do you feel this is the case?
3.2
What guidelines do you currently follow in your department in the diagnosis such as RCR or do you have your own local rules?
16.61
Ultrasound is a main modality that you have at your disposal; Would you agree or disagree?
16.4
In what cases would you refer patients for an MRI of the prostate?
8.3
Has your department ever considered the introduction of an MRI guided biopsy or the need for it?
16.21
Have you seen any trends in prostate cancer treatment?
3.6
What are your sentiments on the introduction of the national prostate cancer screening in Ireland?
16.61
The Gunning Point Index, while excellent for testing the reading age of the questions, did not judge bias or the presence of ambiguous statements. Therefore, the primary reason for the pilot study was to ensure the wording of the questions was correct and accurate also to improve the confidence of the inexperienced interviewer. For the purposes of this study only one urologist and one radiologist were interviewed due to the fact that the researcher found it difficult to obtain participants within the allotted timeframe. A total of 35 participants were contacted of which 8 replied. All participants were followed with a follow up call however many were un-willing to take part.
2.6. CONFIDENTIALITY
Recording of all interviews was deemed necessary to record the interviews as it helped reduce the time required for the interview and ensured transcription was correct. Interviews were recorded using a Philips Dictaphone. All participants were aware that recording of the interview would take place prior to the day of the interview. Principles such as using high quality tapes for recording and masking of names during interviews to ensure anonymity were adhered to throughout the research process (Creswell, 1998). The interviewee was again reminded at the start of the interview that the conversation would be recorded but that they personally would not be referenced by name. A brief summary of the procedure of recording, transcribing and then deletion of the tapes was provided at the beginning of the interview and oral consent received in person.
CHAPTER 3.RESULTS
The comprehensive transcripts containing all the directly transcribed raw data is listed in Appendix D & E. The following results summarize the main points taken from the interviews which have been broken down into two parts A & B. All respondents have been coded using a colour coded system to ensure anonymity. The results are characterized into two sections as different interviews were undertaken with the different professional groups.
The respondents are coded as follows;
Table A
Part A
Consultant Urologists
Hospital 1
A(Red)
Hospital 2
B(Purple)
Hospital 3
C (Green)
Table B
Part B
Consultant Radiologists
Hospital 1
M (Brown)
Hospital 2
N (Grey)
Hospital 3
O (mint green)
Current Trends in Patient Presentation
Current Guidelines
TRUS of the prostate Gland
MRI of the Prostate Gland
MRI Biopsy of the Prostate gland
National Prostate Screening Programme
Part B
Radiologist Interviews
In line with the views of the urologists, all the radiologists interviewed stated categorically that ultrasound biopsy is used in the diagnosis of prostate cancer. This falls within the RCR guidelines and within the most up-to-date NICE guidelines.
Question:
MRI is not used for screening as expected. The question was asked to get a complete overview of the diagnostic pathway.
PSA testing is cost efficient, not invasive with little or no clinically significant side effects. With such an accurate test available the use of MRI in diagnosis would be overkill. This result was expected.
While MRI is advantageous due to add on tools such as spectroscopy showing biochemical information , it was agrees that ultrasound is more beneficial in prostate gland biopsy.
Question:
CHAPTER FOUR: DISCUSSION
4.1. OVERALL AIM
The overall aim of this study was to analyse the current role of ultrasound and Magnetic Resonance Imaging in the diagnosis of prostate cancer. This was undertaken via the interviewing of Consultant Urologists and Radiologists working in the dynamic and challenging field of prostate cancer diagnosis. This study was not carried out on a nationwide basis, resulting in a smaller scale sample size which does not give a true representation of the study population.
4.2 CURRENT TRENDS IN PATIENT PRESENTATION
All health care professionals have witnessed an increase in the number of patients presenting with suspected prostate cancer. This is in line with the values published by the National Cancer Registry of Ireland (NCRI., 2007). The main reason for this increase was felt to be 'increased awareness' among the male population about the signs and symptoms of the disease, this increased awareness has been accredited to agencies such as the Prostate Action Centre which is a segment of the Irish Cancer Society, the Gillette Father's Day campaign, along with the role out of the National Cancer Control Programme. A study undertaken by Fitzpatrick et al (?) found that men had increased awareness in relation to risk factors such as age and family history however awareness is lacking in assessing one's own risk in developing prostate cancer with 43% of people believing that the risk of developing prostate cancer is low.
A second reason for the increase in men presenting was because they are more inclined to search for information about recommended tests and request testing. GP referral guidelines published in 2004 collated by the HSE and NCCP recommended regular PSA testing after the age of fifty was due to increased number of PSA testing being performed by GP's, this could perhaps be accredited to the introduction of the Nationwide Prostate Cancer Referral Guidelines made by joint efforts between the Health Service Executive and the NCCP, this resource was to aid the GP's on what cases to refer to the Rapid Access Prostate Cancer Clinics set up in Ireland. All the urologists agreed that there has been an increase in the numbers of presenting with suspected prostate cancer. The consensus was that public and general practitioners were more aware of the risk. Backing up the urologist views are the statistics from the NCRI stating that the number of PSA tests carried out increased five-fold between 1995 and 2004. This was mirrored in the majority of developed countries as health service funding increased.
4.3 GUIDLEINES IN PROSTATE CANCER DIAGNOSIS
NICE recommends (guideline 27) that before referral to specialist care, men with suspected prostate cancer should have been offered a digital rectal examination and PSA test. The RCR guidelines which are limited to the use of imaging tools recommend the use of ultrasound in cases where biopsy is indicated or required. The NICE guidelines are expansive and inclusive. Local rules that apply in most hospitals have been adapted from the NICE, RCR and WHO guidelines and each individual hospital has chosen the most efficient and cost effective system to facilitate their budgets and maximise the use of the equipment available. Each hospital stated that the above rules were modified and combined to result in the best treatment for the patient and this was necessary as each patient's condition is different and a tailored and unique care pathway is often necessary to treat the patient accordingly. Also, the range of equipment and the level of expertise within the urology and radiology departments meant that each hospital had to adapt their own standard operating procedures and services. This showed that hospitals, wherever possible, are following evidence-based medicine in their bid to give the best possible care but budget constraints may hinder a full menu of services.
4.4. TRANS-RECTAL ULTRASOUND OF THE PROSTATE
When professionals were asked if Trans-rectal ultrasound biopsy was the modality at their disposal in the diagnosis of prostate cancer, opinions differed. 66.6% of the sample size believed this to be the case with one participant stating
another adding' it is the most commonly used tool as ones disposal'.
To address the hypothesis of this study it was to discover if ultrasound was utilized in the diagnosis of prostate cancer. From the above results it is true to say it is used in the diagnosis pathway, however it is more correct to say Transrectal - ultrasound biopsy is the method used in the diagnosis pathway and ultrasound is merely the means by which the biopsy may be performed. In hindsight this hypothesis such of been worded more accurately. Trans-rectal ultrasound biopsy in the diagnosis of prostate cancer is used in the majority of hospitals. It is cost-effective, efficient and allows for accurate biopsy with limited adverse effects or morbidity.
4.5. MAGNETIC RESONANCE IMAGING OF THE PROSTATE GLAND
When the subject on the use of Magnetic Resonance Imaging of the Prostate Gland was broached and in what cases it would be utilized opinions varied substantially. One participant stated it would be used in younger patients to aid the differential diagnosis of pseudo cysts from prostate cancer. The second participant stated that it tends to be used in younger patients with a palpable mass; however, the value of this technique is unknown, representing their uncertainty on the use of it in this case. The final participant stated that MRI is less than helpful in detecting prostate cancer in its early stage, which is when you want to diagnose the disease, hence their reluctance in using this modality in its early stages.
The hypothesis of this study was to prove that Magnetic Resonance Imaging is not used in the diagnosis process of prostate cancer. This has been proven to be the case as all interviewees concurred that MRI is not used. The main reason for this sentiment is, according to one participant, that 'the value of MRI in the diagnosis of prostate cancer is unknown and more research is needed in this area'.
4.6. MAGNETIC RESONANCE IMAGING BIOPSY OF THE PROSTATE GLAND
When the introduction of the introduction of MRI biopsy was raised with both professions it was found that, neither profession believed it was going to be introduced into their hospitals, this was primarily due to the fact that it is considered time consuming and impractical. Nevertheless, it must be stated that if it was present in their hospitals, one out of three stated that it would be utilized. One respondent stated 'it is not available as the expertise is not available'.
It was the overall consensus that the introduction of MRI biopsy will not become readily available in the Republic of Ireland.
4.7. NATIONAL PROSTATE SCREENING PROGRAMME
Sentiments were mixed in relation to the introduction of a National Prostate Cancer Screening Programme. One participant stated that due to the nature of the anxiety caused by the tests it should be an 'individual choice'. Another participant stated this would lead to increased numbers of men being diagnosed and treated for prostate cancer however he felt it is needed within the country. The final participant merely stated that currently within the state we do not have the resources at our disposal currently to undertake this. The views of the interviewees were backed by findings in the literature review such as Ilic et al (2011). Ilic et al (2007) could not draw a conclusive conclusion on the benefit versus risk of screening after a systematic review of the area. Additionally, Sandholm et al (?) found that deaths from prostate cancer did not differ between men screened regularly and those that were not screened. Fitzpatrick et al (?) found that 94% of men believe that by regular screening one reduces their chances of developing prostate cancer. In line with the hypothesis of this study which is 'professionals believe there should be an introduction of a National Cancer Screening Programme in the Republic Of Ireland, this was found not to be the case with 66.6% stating no due to 'over diagnosis' leading to 'over treating' and as a result causing 'unnecessary costs' to the Irish Government.
A national screening programme is the most topical issue with regards to prostate cancer today. As seen from the responses provided, the reaction is mixed. Both the urologists interviewed and relevant studies have agreed that a national screening program will increase cancer figures. Where the deviation lies is whether a national screening programme will decrease mortality sufficiently to warrant the expense and time that the programme would require. Active surveillance was not included in the questionnaire as this would consist of regular PSA testing and DRE tests and a conservative approach and it is the view of the author that the radiology department has little or no involvement in this approach.
4.8. JUSTIFICATION, IMPLICATIONS AND FUTURE STUDY
There has been a sharp increase in the numbers presenting with prostate cancer since the advent of PSA testing which is a cheap and readily accessible test that can be requested by patients in their local GP surgeries. GP support for prostate cancer and the availability of home PSA testing has increased awareness as well as campaigns by national cancer associations.
The study looked at the overall role of the radiology department in the diagnostic pathway of prostate cancer using the following three hypotheses;
TRUS is used in the diagnosis of prostate cancer
MRI is not used in the diagnosis of prostate cancer
The sentiments on a national screening programme
CHAPTER FIVE: CONCLUSION
The overall aim of this study was to validate or discredit three hypotheses. This was undertaken via the means of qualitative data collection through the means of interviews. These interviews provided the information required to meet the needs of this study. The study found that ultrasound is currently one of most used tools at our healthcare professional disposal in the patient care pathway. It main role is to provide real time imaging during biopsy as in line with current literature.
The study deduced that Magnetic Resonance Imaging is not used as a first-line imaging tool primarily due to the cost and availability also it is not deemed sensitive enough in early disease detection. The availability of Magnetic Resonance Imaging Biopsy could potentially open up new avenues for Magnetic Resonance Imaging in the Republic Of Ireland.
The final hypothesis was to question whether there is a strong want for the introduction of a National Prostate Cancer Screening Programme within the Republic of Ireland. The above study found conflicting sentiment on this subject. The majority of participants 66.67% stated that they believed the introduction of this would only lead to over diagnosis and over treatment. This was backed by the literature review which found that though results in many cases were inconclusive as to the overall benefit, a national screening programme would lead to an increase in incidence but the resultant decrease in mortality was insignificant or unjustified. Other issues such as not having the resources and staff availability were raised by the interviewees. The need for effective screening in other areas of cancer such as breast, lung and bowel will inevitably be placed above the need for prostate cancer as their mortality rates are consistently higher, their level of morbidity is higher and unfortunately, the fact that these cancers occur in younger people with more of an economic value to the country as a whole means that their importance will always be deemed higher. Prostate cancer is life threatening and debilitating but not the extent of other more aggressive cancers and many can live to their full life expectancy and die of an unrelated cause while suffering from asymptomatic prostate cancer. The cost of treating cancer is high, in the current economic climate it is likely that the criteria for implementing significant projects such as any cancer screening program will be critiqued on a cost-benefit approach and significant savings would be made by the early detection and treatment of the cancer in question. Unfortunately, it is the view of the author that prostate cancer screening will be seen to not be beneficial to the Exchequer and that any national screening program will be cancelled or postponed indefinitely.
That said, the radiography department of any hospital must be prepared to screen and stage for prostate cancer. It is a large area that requires specialist knowledge and clear and concise guidelines, be they local rules, RCR or NICE guidelines. In an ever-changing health care system where the cost of newer techniques is reduced significantly after they become readily available, the radiology departments should be ready to adapt their procedures and trial newer techniques such as MRI biopsy to see if any significant time or cost savings can be made. Not only should newer techniques be trailed for cost and time savings, they should also be trailed for the incidence of misdiagnosis, over or under detection etc. to ensure that each radiography department is using the most accurate system to diagnose disease.
