Radiotherapy in cT3 prostatic carcinoma: retrospective comparison between neoadjuvant and adjuvant hormonotherapy

Introduction: The aim of this study was to retrospectively compare the clinical outcomes achieved in 2 groups of patients with cT3 prostatic carcinoma undergoing neoadjuvant hormonotherapy and neoadjuvant hormonotherapy plus adjuvant hormonotherapy with external beam radiotherapy.

Patients and methods: One hundred patients with cT3N0M0 prostatic carcinoma underwent radiotherapy to pelvic lymph nodes (45 Gy, 1.8 Gy/fraction) with a booster dose (65-70 Gy) to the prostatic cavity. Forty-four patients received neoadjuvant hormonotherapy (goserelin, starting 2 months before radiotherapy and continuing until the end of irradiation); 56 patients received neoadjuvant hormonotherapy plus adjuvant goserelin until disease progression, if present.

Results: Patients undergoing adjuvant hormonotherapy as compared to those who received exclusive neoadjuvant therapy showed a higher reduction in PSA level below 1.0 ng/ml (p = 0.0211), a lower incidence of biochemical failures (p = 0.0170), a lower incidence of hematogenous metastases (p = 0.0320) and a trend suggestive of a better disease-free survival (p = 0.0660). At univariate analysis (logrank), Gleason score did not show a significant correlation with any of the end points analyzed. To the contrary, patients with tumor <15 mm showed a better local control (p = 0.0347) and biochemical failure-free survival (p = 0.0102). Furthermore, a trend between initial PSA level and incidence of hematogenous metastases was observed (p = 0.0519). Patients with a posttreatment PSA level <1.0 ng/ml had a lower incidence of metastases (p = 0.0237) and a better survival (p = 0.0178); patients with complete clinical response showed a lower incidence of biochemical failures (p = 0.0469). Radiotherapy doses >70 Gy showed a trend with biochemical failure-free survival (p = 0.0554). At multivariate analysis, a correlation between Gleason score and incidence of metastases (p = 0.0232), and between tumor diameter and local control (p = 0.0178) and biochemical failure-free survival (p = 0.0290) was recorded.

Conclusions: In patients with cT3N0M0 prostate carcinoma, prolonged hormonotherapy was shown to be significantly correlated with biochemical failure-free survival and distant metastasis-free survival. Furthermore, tumor size had a significant impact on biochemical failure-free survival as well as on local control.