20 Prostate Cancer

Prostate Cancer

17

THE GEC ESTRO HANDBOOK OF BRACHYTHERAPY | Part II: Clinical Practice Version 1 - 01/12/2014

Management of side effects The main complaints after prostate brachytherapy are urinary problems, as described above. Obstructive symptoms are dealt with by alpha blockers, irritative symptoms may respond to an- ticholinergic drugs. These symptoms are similar for HDR, iodine and palladium seeds, but the onset is earlier with HDR and palla- dium and resolves faster because of the shorter half-life of irradi- ation. Treatment of complete or near complete obstruction is by catheterisation, often only a few days or weeks will be required but sometimes a longer period is needed. In these cases some groups advise the use of a suprapubic catheter which has poten- tial advantages with less discomfort and allowing the patient to urinate spontaneously when they are able to do so. Intermittent trial without catheter is required to determine when the patient may function satisfactorily with the catheter; the use of alpha blockers and antibiotics for intercurrent urinary tract infection may help in achieving success. Some patients may also benefit from intermittent self-catheterisation when there is incomplete bladder emptying. About 10% of patients with obstruction final- ly need a TURP, as described earlier. Proctitis should be treated conservatively, the less intervention the better, although with laser coagulation complications are low. Biopsy should be avoided unless there are significant doubts re- garding the diagnosis as this will in some cases precipitate ulcer- ation and even fistula formation. After combined treatment with external beam radiation and brachytherapy, higher rates of proc- titis are reported [86]. In most patients proctitis is a self- limiting symptom. More serious proctitis can be treated with prednisone enemas, sucralfate or systemic steroids although evidence for their efficacy is poor. In resistant cases there are reports that hy- perbaric oxygen can be helpful. Temporary erectile dysfunction is often encountered after brachytherapy, but resolves in most of the men with normal sexual activity before brachytherapy. Sildenafil and other PDE-5 inhibitors can be helpful in recovery of spontaneous erections. In the majority of men with erectile dysfunction these drugs are successful. Other options include fentolamine or papaverine injections into the penis, intra-urethral alprostadil and vacuum pump.

mentioned before. In general there will be an increase in IPSS for some weeks after implantation which will subside in a few months back to the baseline score [76]. The rate of urinary in- continence is around 1.5%, but differs enormously between stud- ies. Urinary bother with pain and burning urination can occur up to 80% of patients but moderate or severe symptoms are seen in only 1-3%. Normally urinary bother recovers within 1 to 2 months, but occasionally can last several three years. Other rare side effects consist of haemorraghic cystitis, infection and rectourethral fistula [77][78]. Late complications are urethral stenosis and incontinence in a few percent of patients. Prior prostate surgery is a strong pre- dictor for incontinence; the Seattle group using LDR seed brachytherapy found 20% incontinence after TURP and only 1% without TURP [47]. Similarly after HDR brachytherapy a 50% incidence of incontinence was seen when TURP had been per- formed up to 8 months before implant in the combined Michi- gan, Seattle, Kiel series compared to 0.7% where there had been no prior TURP. Urethral stricture rates vary from 0 to 14% [67]. Radiation proctitis occurs in 2-12% following permanent brachytherapy, but is usually mild with intermittent rectal bleed- ing. HDR brachytherapy when used as boost after external beam treatment has been shown in the randomised trial from Mount Vernon to result in no excess of late bowel morbidity compared with external beam alone [68]. HDR monotherapy is associated with a 0-4% risk of diarrhoea, proctitis or rectal bleeding. Ulcer- ation and fistula formation is mainly the result of a higher dose to the rectum, additional external beam irradiation, inappropri- ate biopsy and cauterisation of the mucosa to stop bleeding [79]. With the use of laser coagulation, this complication is much less frequently described. Permanent LDR seed prostate brachytherapy is associated with a lower rate of erectile dysfunction than other treatment mo- dalities. It is still unclear whether the dose to the neurovascu- lar bundle or to the penile bulb is related to erectile dysfunction [80]. Patients with good erectile function before seed implanta- tion have a much higher chance of preservation of their erectile function; other important prognostic factors being, age, tobac- co use and use of hormonal therapy [81]. Approximately 30% of patients may become impotent but over 60% will respond to phosphodiesterase inhibitors such as sildenafil [82]. The amount of ejaculate is often significantly reduced but infertility does not always result. The effects of HDR monotherapy on erectile func- tion are less well documented, however one case control study has suggested that a lower rate of impotence is seen after HDR brachytherapy than after Pd103 LDR seed brachytherapy [83]. Risk of secondary tumors There have been several trials describing the risk of LDR pros- tate brachytherapy on secondary tumours. Although a small risk of second malignancies based on an increased incidence com- pared with matched populations not receiving radiation therapy has been described for external beam prostate irradiation, up to now there does not seem to be an increased risk after LDR brachytherapy. For example in a series of 1888 patients with a median follow up of 10 years, where 63% receive brachythera- py and 37% received radical prostatectomy [84]. Multicenter data showed no difference in secondary tumours between both groups and general population data. A recent systematic review comes to the same conclusion [85]. For HDR no data have been described yet due to the short follow up.