The objective of this study was to evaluate the benefits and risk of adjuvant pelvic radiotherapy aimed at reducing recurrence in women with Stage IB cervical cancer treated by radical hysterectomy and pelvic lymphadenectomy.

Two hundred seventy-seven eligible patients were entered with at least two of the following risk factors: >1/3 stromal invasion, capillary lymphatic space involvement, and large clinical tumor diameter. Of 277 patients, 137 were randomized to pelvic radiotherapy (RT) and 140 to no further treatment (NFT).

Twenty-one (15%) in the RT group and 39 (28%) in the NFT group had a cancer recurrence, 18 of whom were vaginal/pelvic in the RT and 27 in the NFT group. In the RT group, of 18 (13%) who died, 15 died of cancer. In the NFT group, of the 30 (21%) who died, 25 died from cancer. Life table analysis indicated a statistically significant (47%) reduction in risk of recurrence (relative risk = 0.53, P = 0.008, one-tail) among the RT group, with recurrence-free rates at 2 years of 88% versus 79% for the RT and NFT groups, respectively. Severe or life-threatening (Gynecologic Oncology Group grade 3 or 4) urologic adverse effects occurred in 4 (3.1%) in the RT group and 2 (1.4%) in the NFT group; 3 (2.3%) and 1 (0.7%) hematologic; 4 (3.1%) and 0 gastrointestinal (GI); and 1 (0.8%) and 0 neurologic, respectively. One patient's death was attributable to grade 4 GI adverse effects.

Adjuvant pelvic radiotherapy following radical surgery reduces the number of recurrences in women with Stage IB cervical cancer at the cost of 6% grade 3/4 adverse events versus 2.1% in the NFT group.