Established prostate cancer treatments such as radiation therapy or radical prostatectomy aim to treat the whole prostate gland, which may come with the disadvantage of extensive side effects such as impotence, incontinence and potential damage to the rectum and bladder (1,2).
At the same time, they provide only moderate survival benefits compared to active surveillance (which means doing nothing but observing the cancer) (3). It has been shown recently that the largest lesion with the highest tumor grade predominantly influences the progression of PCa (4,5), suggesting that treatment of this so-called index lesion alone would be sufficient (6,7). Focal therapies based on thermal technology, such as Cryosurgery, RFA (Radiofrequency Ablation) or HIFU (High Intensity Focused Ultrasound) have been becoming more popular as a minimally-invasive alternative to established therapies.
IRE (Irreversible Electroporation) is an emerging form of focal therapy that has a clear advantage over the other focal therapy options, as it is a non-thermal ablation modality with elements of tissue selectivity, making it a gentle form of treatment for surrounding tissue and organs. With these properties, IRE has the potential to not only establish itself as a common form of focal therapy for PCa, but also a treatment option for otherwise untreatable cases or cases where most forms of treatment would result in permanent damage.
Other focal treatment methods:
1. Parkin, Donald M. (2006): The evolution of the population-based cancer registry. In: Nature reviews. Cancer 6 (8), S. 603–612. DOI: 10.1038/nrc1948.
2. Pisani, P.; Parkin, D. M.; Ferlay, J. (1993): Estimates of the worldwide mortality from eighteen major cancers in 1985. Implications for prevention and projections of future burden. In: Int. J. Cancer 55 (6), S. 891–903. DOI: 10.1002/ijc.2910550604.
3. Bill-Axelson, Anna; Holmberg, Lars; Garmo, Hans; Rider, Jennifer R.; Taari, Kimmo; Busch, Christer et al. (2014): Radical prostatectomy or watchful waiting in early prostate cancer. In: The New England journal of medicine 370 (10), S. 932–942. DOI: 10.1056/NEJMoa1311593.
4. Liu, Wennuan; Laitinen, Sari; Khan, Sofia; Vihinen, Mauno; Kowalski, Jeanne; Yu, Guoqiang et al. (2009): Copy number analysis indicates monoclonal origin of lethal metastatic prostate cancer. In: Nature medicine 15 (5), S. 559–565. DOI: 10.1038/nm.1944.
5. Mouraviev, Vladimir; Villers, Arnauld; Bostwick, David G.; Wheeler, Thomas M.; Montironi, Rodolfo; Polascik, Thomas J. (2011): Understanding the pathological features of focality, grade and tumour volume of early-stage prostate cancer as a foundation for parenchyma-sparing prostate cancer therapies. Active surveillance and focal targeted therapy. In: BJU international 108 (7), S. 1074–1085. DOI: 10.1111/j.1464-410X.2010.10039.x.
6. Ahmed, Hashim Uddin; Arya, Manit; Freeman, Alex; Emberton, Mark (2012): Do low-grade and low-volume prostate cancers bear the hallmarks of malignancy? In: The Lancet Oncology 13 (11), e509-e517. DOI: 10.1016/S1470-2045(12)70388-1.
7.Guillaumier, Stephanie, et al. "A multicentre study of 5-year outcomes following focal therapy in treating clinically significant nonmetastatic prostate cancer." European urology 74.4 (2018): 422-429.