Salvage image-guided intensity modulated or stereotactic body reirradiation of local recurrence of prostate cancer.

ABSTRACT

OBJECTIVE: To retrospectively evaluate external beam reirradiation (re-EBRT) delivered to the prostate/prostatic bed for local recurrence, after radical or adjuvant/salvage radiotherapy (RT). METHODS: 32 patients received re-EBRT between February 2008 and October 2013. All patients had clinical/radiological local relapse in the prostate or prostatic bed and no distant metastasis. re-EBRT was delivered with selective RT technologies [stereotactic RT including CyberKnife(TM) (Accuray, Sunnyvale, CA); image-guidance and intensity-modulated RT etc.]. Toxicity was evaluated using the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria. Biochemical control was assessed according to the Phoenix definition (NADIR + 2 ng ml(-1)). RESULTS: Acute urinary toxicity G0, 24 patients; G1, 6 patients; G2, 2 patients. Acute rectal toxicity G0, 28 patients; G1, 2 patients; and G2, 1 patient. Late urinary toxicity (evaluated in 30 cases) G0, 23 patients; G1, 6 patients; G2, 1 patient. Late renal toxicity G0, 25 patients; G1, 5 patients. A mean follow-up of 21.3 months after re-EBRT showed that 13 patients were free of cancer, 3 were alive with biochemical relapse and 12 patients were alive with clinically evident disease. Four patients had died two of disease progression and two of other causes. CONCLUSION: re-EBRT using modern technology is a feasible approach for local prostate cancer recurrence offering 2-year tumour control in about half of the patients. Toxicity of re-EBRT is low. Future studies are needed to identify the patients who would benefit most from this treatment. ADVANCES IN KNOWLEDGE Our series, based on experience in one hospital alone, shows that re-EBRT for local relapse of prostate cancer is feasible and offers a 2-year cure in about half of the patients.