22 Radiation therapy in the present Current guidelines recommend the use of highlyconformal radiotherapy techniques, such as intensity-modulated radiation therapy (IMRT) or volumetric arch therapy (VMAT). It is possible to design intricately shaped RT volumes, limiting the exposure of surrounding normal tissues. When combined with image guidance, localisation is even more accurate, less normal tissue is included in the treatment elds, which in turn makes it possible to safely deliver higher doses to the prostate tumour. Also, due to the specic biology of prostate cancer, it is now known that daily treatments with higher dosages are more effective than using a higher number of smaller daily fractions. When the overall radiotherapy treatment duration is shortened by using higher daily doses, we use the term “hypofractionation”. Where conventional fractionation for prostate cancer RT uses up to 40 fraction 2Gy daily over eight weeks, moderately hypocfrationated RT uses anything from 20 to 28 fractions of 2.4 - 3Gy over four to six weeks, and extreme hypofractionation, or stereotactic body radiotherapy (SBRT) can be done in four to ve fractions of 6 - 10Gy, typically 3 times per week, shortening overall treatment time to just about two weeks. Currently IMRT and VMAT are available to most patients and moderate hypofractionation is recommended for denitive treatments in all risk groups, including patients in whom pelvic nodal radiotherapy is necessary. Treatment toxicities mainly affect the gastrointestinal tract (GIT) and genito-urinary (GU) system. Acute toxicities develop during radiotherapy and can continue up to three months after completion, whereas late toxicities develop from three months and later after treatment. GIT complications manifest as rectal bleeding, pain and urgency, and GU side-effects include hematuria, frequency and urgency, retention, and in rare cases urinary incontinence. Radiotherapy also can contribute to erectile dysfunction, especially in cases where ADT is used. Newer treatment techniques have reduced the occurrence of radiation induced proctitis signicantly, especially chronic radiation proctitis. Published values differ widely, but are typically (4) around 2% (or less) grade 3 proctitis at ve years. Unfortunately, due to the anatomy of the urinary bladder and the prostatic urethra, late GU toxicities remain similar at about 15% at 5 years, despite technological advances. A concern when using high daily fractions, as used with SBRT, is a possible increase in late toxicities. Fortunately, there does not seem to be a signicantly higher incidence as (4) long as guidelines are adhered to. Conclusion Radiation therapy plays a major role in the management of localised prostate cancer. All risk groups can be managed effectively with RT, and it is possible and necessary to individualise treatment to each patient’s specic disease and global health needs. The addition of ADT in cases of intermediate- and especially high-risk prostate cancer, with or without abiraterone offers further survival benets, albeit at the cost of more sideeffects. Because of the good prognosis of most patients with prostate cancer, it is very important to keep quality of life in mind and aim to keep treatment toxicity as low as possible. Research is ongoing and newer technologies are constantly being developed. In the past decade overal treatment time has reduced from 8 to under 6 weeks, with lower rates of GI toxicity, and in some cases denitive radiotherapy can even be delivered in ve treatments over 2 weeks. Any patient, who does not qualify for radical surgery, can be referred with condence to the radiation oncologist for safe and effective management of their prostate cancer. References 1. INITIAL RISK STRATIFICATION AND STAGING WORKUP FOR CLINICALLY LOCALIZED DISEASE Version 1.2023, 09/16/22 © 2022 National Comprehensive Cancer Network® (NCCN®) 2. Hamdy F, Donovan J, Lane A, et al. Fifteen-Year Outcomes after Monitoring, Surgery, or Radiotherapy for Prostate Cancer. The New England Journal of Medicine;2023 DOI: 10.1056/NEJMoa2214122 3. Attard G, Murphy L, Clarke NW, et al. Systemic Therapy in Advancing or Metastatic Prostate cancer: Evaluation of Drug Efcacy (STAMPEDE) investigators. Abiraterone acetate and prednisolone with or without enzalutamide for high-risk non-metastatic prostate cancer: a meta-analysis of primary results from two randomised controlled phase 3 trials of the STAMPEDE platform protocol. Lancet. 2022 Jan 29;399(10323):447-460. DOI: 10.1016/S0140-6736(21)02437-5. 4. Widmark A, Gunnlaugsson A, Beckman L, et al. Ultrahypofractionated versus conventionally fractionated radiotherapy for prostate cancer: 5-year outcomes of the HYPO-RT-PC randomised, non-inferiority, phase 3 trial. Lancet 2019;394:385-95. Image References Image 1: https://www.sciencedirect.com/science/article/pii/S2452109420 302608 Image 2: https://www.researchgate.net/gure/Axial-view-of-a-volumetricarc-therapy-VMAT-treatment-plan-for-prostatecancer_g2_321409674 UROLOGY, URO-ONCOLOGY AND SEXOLOGY UPDATE
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