Early Detection and Treatment of Prostate Cancer – Opportunities and Controversies

More than 24,000 men are diagnosed with prostate cancer each year in Australia,ⁱ  as well as approximately 4,000 men in New Zealand.ⁱⁱ Around 1 in 5 men are at risk of a diagnosis before the age of 85, with key risk factors including a family history of prostate, breast or ovarian cancer. Prostate cancer has long been one of the most commonly diagnosed cancers in Australia.ⁱⁱⁱ 

Survival rates depend significantly on how far the prostate cancer has advanced. Most cancer-related data and research uses the Surveillance, Epidemiology and End Results’ (SEER) Summary Stage^iv database to distinguish what stage a cancer has reached. These include in situ, localised, regional, distant and unstaged. The first two are early-stage cancers, while regional and distant represent late-stage cancer. ‘Unstaged’ refers to situations where there is insufficient information to determine how advanced the cancer is.^v  

It has been estimated that localised and regional prostate cancer has a 5-year survival rate of up to 99%, while distant cancer is at 34%.^vi Another source suggests that survival rates beyond 1, 3 and 5 years reduce drastically for stage IV prostate cancers compared to stage I, II and III – down to 71%, 48% and 36%, respectively, from almost 100% across the board.^vii 

Modifiable risk factors

As is true of most systemic health conditions, there are various risk factors associated with prostate cancer. Aside from the non-modifiable factors already mentioned, lifestyle factors must also be considered and improved where possible. For example, smoking has been shown to increase both incident and fatal prostate cancer rates.^viii There is also evidence to suggest that obesity and a sedentary lifestyle may increase the risk of prostate cancer.^ix 

Screening and its controversies 

Despite the clear need for early diagnosis, screening for and managing early detection is a challenging and controversial area of medicine around the world.^x Prostate-specific antigen (PSA) screening, in particular, is a widely debated procedure. The Prostate Cancer Foundation of Australia (PCFA) and Cancer Council Australia acknowledge that PSA testing is not recommended as a population-based screening programme.^xi  

Though it is the primary method of testing for prostate cancer by assessing PSA concentration in the blood, it is known to produce unreliable conclusions – PSA is not specific to cancer and can therefore deliver a false-positive result. The Foundation’s clinical guidelines estimate over-diagnosis from testing to be 20-40%. Treatment for prostate cancer can cause adverse side effects, including urinary incontinence, erectile dysfunction, and bowel problems. As such, inadvertently exposing someone who doesn’t actually have prostate cancer can leave them in a worse situation than when they started. The PCFA guidelinesix^ix highlight the importance of educating patients to ensure they fully understand all of the benefits and risks of PSA testing, before going ahead. They also recommend reviewing frequency of testing and patient age before proceeding.

Prostate cancer treatment

Where prostate cancer is detected, treatment can include active surveillance, surgery, radiation or chemotherapy, androgen deprivation therapy and transurethral resection of the prostate.^xii Focal laser ablation has emerged as a new and effective treatment therapy for prostate cancer, with research supporting its safety and efficacy.^xii When using such a procedure, the location of the ablation zone and its proximity to important anatomical structures can make the process more challenging. Therefore, the accuracy of treatment is vital in order to achieve results without damaging the surrounding tissues.

It was with this in mind that AngioDynamics developed NanoKnife® – the first surgical ablation system to utilise Irreversible Electroporation (IRE) technology. It uses non-thermal energy to create permanent nanopores in the cell membrane, disrupting cellular homeostasis to incite cell death while preserving the surrounding tissues. The technology has been indicated for use in prostate cancer treatment and is currently available in Australia and New Zealand. The clinical data^xiv is very positive, with papers already showing extremely good long-term outcomes for both halting disease progression and maintaining the patient’s quality of life. In particular, Stricker et al^xv demonstrated focal IRE therapy to be a safe and effective treatment option for men with localised and distant prostate cancer with 5-10 years follow-up. Further studies are also on-going. 

The future of prostate cancer management

It is clear that further development of screening techniques and treatment options is needed to offer patients with prostate cancer more effective solutions. Current technological advancements are paving the way for efficient management of the condition and are key to creating a brighter future for those affected. 
 

ⁱ Better Health Channel. Prostate cancer. https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/prostate-cancer [Accessed January 2024]

ⁱⁱ Southern Cross Medical Library. Prostate cancer symptoms causes and treatment. https://www.southerncross.co.nz/medical-library/cancers/prostate-cancer-symptoms-causes-and-                           treatment#:~:text=Each%20year%20in%20New%20Zealand,Zealand%20appears%20to%20be%20increasing. [Accessed January 2024]

ⁱⁱⁱ Australian Government. Cancer Australia. Prostate cancer in Australia statistics. https://www.canceraustralia.gov.au/cancer-types/prostate-cancer/statistics [Accessed January 2024]

^iv National Cancer Institute. SEER Registrar Staging Assistant. SEER*RSA. https://staging.seer.cancer.gov/ [Accessed March 2024]

^v Dhec. Common Terms in Cancer Data. https://scdhec.gov/CancerRegistry/Definitions#:~:text=The%20SCCCR%20uses%20the%20SEER,situ%20are%20considered%20pre%2Dinvasive. [Accessed March  2024]

^vi American Cancer Society. Cancer Facts & Figures 2024. Atlanta: American Cancer Society. Obtained from American Cancer Society https://www.cancer.org/cancer/types/prostate-cancer/detection-diagnosis-staging/survival-rates.html [Accessed January 2024]

^vii National Cancer Control Indicators. Relative survival by stage at diagnosis (prostate cancer). April 2019. https://ncci.canceraustralia.gov.au/outcomes/relative-survival-rate/relative-survival-stage-diagnosis-prostate-cancer [Accessed January 2024]

^viii Huncharek M, Haddock KS, Reid R, Kupelnick B. Smoking as a risk factor for prostate cancer: a meta-analysis of 24 prospective cohort studies. Am J Public Health. 2010 Apr;100(4):693-701. doi: 10.2105/AJPH.2008.150508. Epub 2009 Jul 16. PMID: 19608952; PMCID: PMC2836346.

^ix Saha, A., Kolonin, M.G. & DiGiovanni, J. Obesity and prostate cancer — microenvironmental roles of adipose tissue. Nat Rev Urol 20, 579–596 (2023). https://doi.org/10.1038/s41585-023-00764-9

^x Cuzick J, Thorat MA, Andriole G, Brawley OW, Brown PH, Culig Z, Eeles RA, Ford LG, Hamdy FC, Holmberg L, Ilic D, Key TJ, La Vecchia C, Lilja H, Marberger M, Meyskens FL, Minasian LM, Parker C, Parnes HL, Perner S, Rittenhouse H, Schalken J, Schmid HP, Schmitz-Dräger BJ, Schröder FH, Stenzl A, Tombal B, Wilt TJ, Wolk A. Prevention and early detection of prostate cancer. Lancet Oncol. 2014 Oct;15(11):e484-92. doi: 10.1016/S1470-2045(14)70211-6. PMID: 25281467; PMCID: PMC4203149.

^xi National Health and Medical Research Council. PSA testing and early management of test-detected prostate cancer. Clinical practice guidelines. chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://www.pcfa.org.au/media/611412/PSA-Testing-Guidelines-Overview.pdf [Accessed January 2024]

^xii Cancer Council Victoria. Prostate Cancer. https://www.cancervic.org.au/cancer-information/types-of-cancer/prostate_cancer/treatment_for_prostate_cancer.html [Accessed January 2024]

^xiii Wenger H, Yousuf A, Oto A, Eggener S. Laser ablation as focal therapy for prostate cancer. Curr Opin Urol. 2014 May;24(3):236-40. doi: 10.1097/MOU.0000000000000044. PMID: 24625427; PMCID: PMC4071166.

^xiv PRESERVE: Pivotal Study of the NanoKnife System for Ablation of Prostate Tissue in an Intermediate-Risk Patient Population. https://www.angiodynamics.com/studies/preserve/ [Accessed February 2024]

^xv Scheltema MJ, Geboers B, Blazevski A, Doan P, Katelaris A, Agrawal S, Barreto D, Shnier R, Delprado W, Thompson JE, Stricker PD. Median 5-year outcomes of primary focal irreversible electroporation for localised prostate cancer. BJU Int. 2023 Jun;131 Suppl 4:6-13. doi: 10.1111/bju.15946. Epub 2022 Dec 28. PMID: 36495481.