Radical radiotherapy is offered to patients who are potentially curable. Palliative radiotherapy to prostate is given in patients who have metastatic disease but have local symptoms especially intractable bleeding. Palliative radiotherapy is also offered to painful bone metastases.
Radiotherapy involves applying radiation to the prostatic tissue. The idea is that it kills the cancer cells. However the prostate still remains in place.
Radiation could be delivered from outside the body ( external beam radiotherapy EBRT) or directly to the prostate (brachytherapy). With advancement in technology and science, radiotherapy delivery to the prostate from outside (external beam ) has made further progress . We now have Intensity Modulated Radiotherapy(IMRT) and Image Guided Radiotherapy (IGRT ) and stereotactic radiotherapy (Cyberknife).
External beam radiotherapy, patient is usually subjected to a scan which helps in planning the radiation delivered to the prostate. The patient then has marking on the surface of the abdomen which helps the machine and patient placement on a daily basis. Per dose of radiotherapy involves spending about half hour in the hospital and few minutes on the machine. Usually EBRT is delivered as one dose / 5 days a week/ 5-6 weeks. Due to difference in technology, Cyberknife RT is delivered usually over 2-3 weeks. The side effects of radiotherapy are usually not felt in the first few weeks. Towards the end of the RT and immediately afterwards (lasting for a few weeks), side effects such as urinary urgency, bowel urgency, mild / intermittent hematuria (blood in the urine). The patients may also feel tired. Usually, the vast majority of the symptoms settle down. Brachytherapy, on the other hand, is delivered in a day. There are two varieties; Low Dose Brachytherapy (LDR) and High Dose Brachytherapy (HDR). In India, HDR is available. The patients usually need an anaesthetic for placement of delivery channels and the radiation source is loaded after the placement (After Loading). Usually catheter is required for this. Subsequently, catheter gets removed. The side effects of brachy are mostly felt in the worsening of urinary symptoms. Hence patients with severe urinary symptoms before treatment would not be a ideal candidate for the treatment
Overall the side effects of incontinence and impotence happen with any form of radiation. Impotence rates are lower with brachytherapy. Incontinence, inevitably, is felt sometime after the radiation. It is usually related to poor flow and urgency which are related to the changes that have happened in the prostate and bladder. Some patients may require an operation called Transurethral resection of prostate ( TURP) , to improve the flow.