Objective The aim of this study was to investigate the therapeutic response and toxicity of intensity-modulated radiation therapy (IMRT) or conventional radiotherapy (c-RT) as adjuvant therapy in patients with pelvic locoregional recurrence of cervical cancer after radical surgery.

Methods This retrospective study included 161 patients with unresectable pelvic locoregional recurrence of cervical cancer after radical surgery between March 2003 and May 2012. All patients were initially diagnosed with International Federation of Gynecology and Obstetrics stage IB-IIA cervical cancer and received radical hysterectomy and pelvic lymphadenectomy. A total of 82 patients were treated with c-RT, whereas the remaining 79 patients underwent IMRT. Intracavitary brachytherapy and concurrent chemotherapy were performed during external irradiation.

Results The mean dose delivered to the planning target volume was significantly higher in the IMRT group than in the c-RT group (61.8 vs 50.3 Gy, P = 0.029). Intensity-modulated radiation therapy plans yielded better dose sparing of small bowel, bladder, and rectum than did c-RT (P < 0.05). Moreover, the IMRT patients experienced less acute and chronic toxicities (P < 0.05) and better short-term effects (complete response + partial response) than did those treated with c-RT (89.9% vs 63.4%, P = 0.03). Three- and 5-year overall survival rates were significantly higher in the IMRT group than in the c-RT group (3-year: 58.4% vs 39.1%, P = 0.012; 5-year: 35.4% vs 21.4%, P = 0.007). Furthermore, 5-year progression-free survival rates were significantly higher in the IMRT group than in the c-RT group (26.1% vs 15.1%, P = 0.031).

Conclusions Intensity-modulated radiation therapy achieved outcomes superior to c-RT in patients with pelvic locoregional recurrence of cervical cancer after radical surgery. The acute and chronic toxicities were acceptable, and the adjacent organs at risk were well protected.