Your question addresses a situation quite commonly encountered by men being considered for prostate cancer radiotherapy.
As all men age, their prostate glands enlarge to some degree. This condition is known as benign prostatic hyperplasia (BPH), and results in urinary difficulties such as urinary frequency, urgency, hesitancy, slow stream and dribbling. Medication can often successfully manage these symptoms when treatment is required. But in some situations, the excess prostate tissue interfering with the flow of urine must be surgically removed through a procedure known as transurethral resection of the prostate (TURP).
TURP improves urinary flow by hollowing out a cavity in the centre of the prostate. For men who are subsequently diagnosed with prostate cancer, however, this cavity causes problems if they are considering brachytherapy (seed therapy) as a treatment option. Brachytherapy is most effective when the seeds can be distributed in a set pattern throughout the prostate; this is not possible if there is a large cavity in the middle of the gland.
Fortunately, this cavity is not a limitation for external beam radiotherapy. Men who have had a TURP can quite safely receive very high doses of radiation with intensity modulated radiotherapy (IMRT) or three-dimensional conformal therapy (3D-CRT).
In fact, a TURP may be recommended before external beam radiotherapy for men with very restricted urinary flow, in order to lessen the risk of developing complete urinary blockage during the course of treatment. In this case, radiotherapy would be delayed for eight to 12 weeks after the TURP operation, to ensure that the prostate was completely healed before starting radiation treatment.
