Postoperative chemoradiation therapy in high-risk cervical cancer: Re-evaluating the findings of gynecologic oncology group study 109 in a large, population-based cohort

Purpose To review the National Cancer Database (NCDB) to evaluate postoperative high-risk cervical cancer patients for factors associated with a benefit from chemoradiation therapy (CRT) over external beam radiation therapy alone (EBRT). Methods and Materials The National Cancer Database was queried for women with cervical cancer treated with hysterectomy and adjuvant EBRT from 2002 to 2012. Only patients with pathologic lymph node involvement (LN+), positive surgical margins, and/or parametrial invasion were included in our analysis (on the basis of Peter's criteria). Univariable and multivariable analyses (MVA) were performed, and hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated to investigate for factors associated with of CRT utilization and overall survival (OS). Results A total of 3053 patients met inclusion criteria, and 2479 received adjuvant CRT (81%), whereas 574 (19%) received EBRT alone. Factors associated with increased CRT utilization on MVA included age <69 years, year of diagnosis ≥2008, non-adenocarcinoma histology, and LN+. Use of CRT improved OS among the entire cohort on MVA (HR 0.76, CI 0.601-0.962; P=.022). On MVA, CRT improved OS in patients with LN+ as their sole Peter's criteria (HR 0.58, CI 0.413-0.814; P=.002). Chemoradiation therapy did not improve OS in patients with only positive margins (P=.73), only parametrial invasion (P=.95), or any combination of these 2 factors without LN+ (P=.63). Conclusions The use of adjuvant CRT after hysterectomy improves OS in patients with high-risk cervical cancer compared with EBRT alone, but this benefit seems to be restricted to patients with LN+. The benefits of adjuvant CRT over EBRT alone in patients with parametrial invasion and/or positive margins (without nodal involvement) are unknown.