In the next in our series, GP Dr Roger Henderson debunks common myths about prostate cancer – and highlights some less well-known facts
MYTHS
Myth 1. Prostate cancer rarely affects those under 65 years
Although increasing age is the most important risk factor for developing prostate cancer, around 25% of cases occur in men below the age of 65.
This means a younger man who presents with symptoms that could be attributed to prostate cancer should be assessed for this possible diagnosis rather than being reassured it is unlikely because of their age.
The age-specific incidence rates of prostate cancer rise steeply from the ages of around 45-49 and peak in the 75-79 age group, then drop slightly.1 Unsurprisingly, prostate cancer mortality is strongly related to age, with the highest mortality rates being in older men.
Nonetheless, worldwide the incidence of prostate cancer has increased for all groups between 15 and 40 years, and increased globally at a steady rate averaging 2% per year since 1990. There should be a high index of clinical suspicion in men under the age of 65 if clinically applicable, especially in men with a strong family history of prostate cancer or from particular ethnic groups (see below).2
Myth 2. Vasectomy directly increases the risk of prostate cancer
Many studies have looked at the possibility of a link between vasectomy and a subsequent increased risk of prostate cancer. While some have found a small increased risk of prostate cancer, overall the weight of evidence to date does not support a causal link. This FSRH guidance advises there is no evidence of a causal relationship between vasectomy and cancer of the prostate, and that any reported association of an increased risk is very small, and explained by bias or confounding factors such as age.
Myth 3. Erectile dysfunction after radical prostatectomy is difficult to treat
The early initiation of PDE5 inhibitors after radical prostatectomy can promote early recovery and preservation of erectile function, and in some studies around 73% of men who have had a nerve-sparing prostatectomy have reported achieving successful erections using these drugs.3,4 PDE5 inhibitors have a good compliance rate, with up to 89% still taking them at two years following radical prostatectomy.5
Transurethral alprostadil can also prove effective with efficacy rates of 70% of men post-prostatectomy believing that they have an erection sufficient for intercourse, and over 50% managing to have sexual intercourse on this type of treatment.6
Myth 4. A PSA test can be done at any time
Men aged over 50 may approach their GP to ask for a PSA test for reassurance. However, unless the GP asks the patient some specific questions, an inaccurate test result may occur. Current guidelines are that at the time of a PSA test, the patient should not have:
● An active urinary tract infection.
● Ejaculated in the previous 48 hours.
● Had a prostate biopsy in the previous six weeks.
● Exercised vigorously in the previous 48 hours.
● Had a recent digital rectal examination (if possible, do the blood test before the examination; otherwise, wait for one week afterwards).
● Had receptive anal intercourse for 48 hours before a PSA test – this is an essential requirement for gay, bisexual, and other men who have sex with men.
In addition, any PSA blood sample should reach a laboratory within 16 hours.
Myth 5. A lack of lower urinary tract symptoms makes prostate cancer unlikely
On the contrary, most men with prostate cancer are asymptomatic at presentation, and initial suspicion is only raised following screening with PSA testing and digital rectal examination (DRE). Lower urinary tract symptoms (LUTS) do not particularly raise the suspicion of prostate cancer because LUTS are common in older men and are rarely the presenting symptom of prostate cancer (although locally advanced prostate cancer may cause obstructive LUTS). There is significant crossover in symptoms between prostate cancer and benign conditions affecting the prostate such as benign prostatic hypertrophy (BPH) and prostatitis,7 making it very challenging to distinguish between them on the basis of symptoms. Late symptoms may include fatigue due to anaemia, bone pain, paralysis from spinal metastases, and renal failure from bilateral ureteral obstruction.8
FACTS
Fact 1. Overweight and obesity are linked to worse prostate cancer outcomes
Overweight and obese men with prostate cancer are at an increased risk of disease recurrence, treatment-related adverse effects, obesity-related comorbidities, earlier progression and development of metastatic disease, and higher all-cause and prostate cancer-specific mortality. This may be linked to an increased inflammatory environment and metabolic irregularities associated with excess fat. Fat loss strategies using exercise and nutrition programmes may slow down prostate cancer progression and improve prognosis.9
One population study found that individuals with a higher BMI had a lower risk of prostate cancer diagnosis but a higher risk of prostate cancer mortality that was unlikely to be due to delayed prostate cancer detection.10 However, some studies have also reported that high-fat diets may increase the risk of prostate cancer.11,12
Fact 2. Race has an impact on PSA values and diagnosis
Several studies have observed that average PSA values vary among men from different ethnic groups. Black men have higher PSA levels on average and both higher prostate cancer incidence and mortality than White men, while Asian men tend to have lower prostate cancer incidence and mortality than White men.13 (Much of this evidence comes from the USA, and information from UK populations is more limited).
In both the UK and USA, research has shown that Black men have the highest risk of receiving a prostate cancer diagnosis, a pattern mirrored by their increased lifetime risk of dying from the disease.14 The incidence of advanced stage prostate cancer at diagnosis was similar for Black and White men with a raised PSA result, but lower for Asian men.15
Fact 3. A negative biopsy does not exclude prostate cancer
A negative prostate biopsy does not exclude the possibility of a diagnosis of prostate cancer, especially if there is significant clinical suspicion, or if a PSA result is persistently elevated or rising. If there is a negative biopsy but an elevated PSA, then a further PSA should be performed – ideally within 6 months of the negative biopsy. Depending on these results, a repeat biopsy with MRI targeting should be considered. A combined MRI-targeted and systematic biopsy approach improves the detection of clinically significant prostate cancer.
Fact 4. A careful personal and family history may identify patients at increased risk of prostate cancer
Some men with a significant personal or family history relevant to prostate cancer risk may warrant genetic risk assessment (including counselling and genetic testing). Genetic testing may be considered in people with:
● A first- or second-degree relative with metastatic prostate cancer; ovarian cancer; breast cancer (male diagnosed at any age or female diagnosed at aged <45 years); colorectal or endometrial cancer diagnosed at <50 years; or pancreatic cancer.
● Two or more first- or second-degree relatives with breast, prostate, colorectal, or endometrial cancer at any age.
● A personal history of breast cancer.
● Known or suspected family or personal history of a cancer susceptibility gene mutation (eg, BRCA1 or BRCA2).
● Ashkenazi Jewish ancestry.
Fact 5. Most men diagnosed with prostate cancer survive for 10 years or more
Prostate cancer is often survivable, with overall survival depending on the initial stage of disease at the time of diagnosis. Almost 8 in 10 (77.6%) men diagnosed with prostate cancer in England survive their disease for 10 years or more. Five-year relative survival rates by prostate cancer stage at diagnosis (2014 to 2020 data) are 100% (localised disease), 100% (regional) and 36.6% (distant).
In line with this, men with low-grade prostate cancers (Gleason score 2-4) are at low risk of dying from prostate cancer during 20 years of follow-up (6 deaths per 1,000 person-years). Men with high-grade prostate cancers (Gleason score 8-10) are at relatively increased risk of dying from prostate cancer within 10 years of diagnosis.16
Dr Roger Henderson is a GP based in Scotland
References
1. Wilt T, Ahmed H. Prostate cancer screening and the management of clinically localized disease. BMJ 2013;346:f325
2. Bleyer A, Spreafico F, Barr R. Prostate cancer in young men: An emerging young adult and older adolescent challenge. Cancer 2019; 126:46-57
3. Nathan A, Shukla S, Sinha A et al. Immediate post-operative PDE5i therapy improves early erectile dysfunction outcomes after robot assisted radical prostatectomy (RARP). J Robot Surg 2022;16:37-43
4. Briganti A. Gallina A, Suardi N et al. Predicting erectile function recovery after bilateral nerve sparing radical prostatectomy: a proposal of a novel preoperative risk stratification. J Sex Med 2010;7(7):2521-31
5. Albaugh J, Adamic B, Chang C et al. Adherence and barriers to penile rehabilitation over 2 years following radical prostatectomy. BMC Urol 2019 Oct 7;19(1):89
6. Raina R, Agarwal A, Zaramo C et al. Long-term efficacy and compliance of MUSE for erectile dysfunction following radical prostatectomy: SHIM (IIEF-5) analysis. Int J Impot Res 2005 Jan-Feb;17(1):86-90
7. Merriel S, Funston G, Hamilton W. Prostate cancer in primary care. Adv Ther 2018 Sep;35(9):1285-94
8. Leslie S, Soon-Sutton T, Skelton W. Prostate Cancer.In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan.
9. Wilson R, Taaffe D, Newton R et al. Obesity and prostate cancer: A narrative review. Crit Rev Oncol Hematol 2022;169:103543
10. Hurwitz L, Dogbe N, Hughes Barry K et al. Obesity and prostate cancer screening, incidence, and mortality in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. J Natl Cancer Inst 2023;115(12):1506-14
11. Labbé D, Zadra G, Yang M et al. High-fat diet fuels prostate cancer progression by rewiring the metabolome and amplifying the MYC program. Nat Commun 2019;10(1):4358
12. Cirne F, Kappel C, Zhou S et al. Modifiable risk factors for prostate cancer in low- and lower-middle-income countries: a systematic review and meta-analysis.Prostate Cancer Prostatic Dis 2022 Sep;25(3):453-462
13. Barlow M, Down L, Mounce L et al. Ethnic differences in prostate-specific antigen levels in men without prostate cancer: a systematic review. Prostate Cancer Prostatic Dis 2023;26, 249–56
14. Delon C, Brown K, Payne N et al. Differences in cancer incidence by broad ethnic group in England, 2013–2017. Br J Cancer 2022;126;17–1773
15. Down L, Barlow M, Bailey S et al. Association between patient ethnicity and prostate cancer diagnosis following a prostate-specific antigen test: a cohort study of 730,000 men in primary care in the UK. BMC Med 2024;22:82
16. Albertsen P, Hanley J, Fine J. 20-year outcomes following conservative management of clinically localized prostate cancer. JAMA 2005 May 4;293(17):2095-101
Note that the UK spends twice as much on breast cancer research than on prostate cancer (£51m. vs £24m 2020/21. NCRI).
Breast cancer has a well established Breast Cancer screening program, while prostate cancer does not.
Both breast and prostate cancers cause around 7% of all cancer deaths, around 12,000 per year each.
“30% of patients with high-risk prostate cancer do not get curative treatment with either surgery or radiotherapy, with performance varying between 20% and 43% across different services”
“Professor Ajay Aggarwal, clinical director at NatCan, which is run by the Royal College of Surgeons (RCS) for NHS England and the Welsh government, said it was concerning so many patients were not getting the recommended treatment”.
The National Cancer Audit Collaborating Centre (NatCan).
“● Had a recent digital rectal examination (if possible, do the blood test before the examination; otherwise, wait for one week afterwards).”
The need to avoid PSA check after DRE does not appear to be mentioned in the link you give. In fact Prostate Cancer UK recommends that there is no need for a delay. Supporting evidence would help clarify whether this may also be a myth.
https://prostatecanceruk.org/media/zvypxfhm/best-practice-pathway-prereferral.pdf