Effectiveness of adjuvant systemic chemotherapy for intermediate-risk stage IB cervical cancer

OBJECTIVE: To examine the effectiveness of systemic chemotherapy following radical hysterectomy for women with intermediate-risk stage IB cervical cancer. MATERIALS AND METHODS: This is a retrospective analysis of a previously organized nation-wide cohort study examining 6,003 women with stage IB-IIB cervical cancer who underwent radical hysterectomy between 2004 and 2008 in Japan. Survival of 555 women with stage IB cervical cancer in the intermediate-risk group (deep stromal invasion > 50%, large tumor size > 4 cm, and lympho-vascular space invasion [LVSI]) were examined based on adjuvant therapy patterns: chemotherapy alone (n = 223, 40.2%), concurrent chemo-radiotherapy (n = 172, 31.0%), and radiotherapy alone (n = 160, 28.8%). RESULTS: The most common intermediate-risk pattern was LVSI with deep stromal invasion (n = 216, 38.5%). The most common chemotherapeutic choice was taxane/platinum (52.2%). Women with adenocarcinoma/adenosquamous histology were more likely to receive chemotherapy (P = 0.03), and intermediate-risk pattern was not associated with chemotherapy use (P = 0.11). Women who received systemic chemotherapy had disease-free survival (5-year rate, 88.1% versus 90.2%, adjusted-hazard ratio (HR) 0.98, 95% confidence interval (CI) 0.52–1.83, P = 0.94) and cause-specific survival (95.4% versus 94.8%, adjusted-HR 0.85, 95% CI 0.34–2.07, P = 0.71) similar to those who received concurrent chemo-radiotherapy on multivariable analysis. Similar results were seen among 329 women with multiple intermediate-risk factors (5-year rates for disease-free survival, chemotherapy versus concurrent chemo-radiotherapy, 87.1% versus 90.2%, P = 0.86; and cause-specific survival 94.6% versus 93.4%, P = 0.82). Cumulative local-recurrence (P = 0.77) and distant-recurrence (P = 0.94) risks were similar across the adjuvant therapy types. CONCLUSIONS: Our study suggests that systemic chemotherapy may be an alternative treatment choice for adjuvant therapy in intermediate-risk stage IB cervical cancer.