Timing of radio-sensitizing chemotherapy initiation and impact on overall survival of patients with locally advanced cervical cancer undergoing definitive chemoradiation (358)

Abstract

Listen

Translate article

<b>Objectives:</b> To investigate the impact of delay in radio-sensitizing chemotherapy initiation on the survival of patients with locally advanced cervical cancer (LACC) receiving definitive chemoradiation. <b>Methods:</b> Patients diagnosed between 2004-2015 with LACC (FIGO 2009 stage IB2-IVA), who received external beam radiotherapy of at least 45 Gy, known radiation-chemotherapy interval and had at least one month of follow-up were identified in the National Cancer Database. Patients were categorized into same-day chemotherapy and radiotherapy initiation, same week (within one week from radiotherapy initiation), delayed (1-2 weeks from radiotherapy initiation), and significantly delayed (2-3 weeks from radiotherapy initiation). Overall survival was compared with the log-rank test while the Cox model was constructed to control for a priori selected confounders. <b>Results:</b> A total of 11600 patients who met the inclusion criteria were identified; 6079 (52.4%) initiated chemotherapy the same day as radiotherapy, 4513 (38.9%) initiated chemotherapy within one week, while 733 (6.3%) and 275 (2.4%) patients initiated chemotherapy 1-2 week (delayed) and 2-3 weeks (significantly delayed), respectively, after radiotherapy started. A higher percentage of patients with comorbid conditions was observed in the delayed (17.8%) and significantly delayed (15%) groups compared to the same day (12.4%) and same week (14.5%) groups, p<0.001. Similarly, a higher percentage of patients in the significantly delayed (62.9%) and delayed (54%) groups had stage III-IVA disease compared to those in the same day (45.2%) and same week (47%) groups (p<0.001). Lastly, a higher percentage of Black patients was observed in the significantly delayed (26.5%) and delayed (20.5%) groups compared to the same day (15.2%) and same week (18.3%) groups (p<0.001). Median overall survival was 103.3 and 91.93 months for same day and same week groups compared to 69.19 and 39.23 months for the delayed and significantly delayed groups (p<0.001 from log-rank). Following stratification by disease stage, there was no difference in OS between the four groups for stage IB2-II disease (p=0.17). For patients with stage III-IVA, median OS was better for patients in the same day (median: 53.68 months) group compared to those in the same week (median: 41.13 months), delayed (median: 38.28 months), and significantly delayed (median: 32.49 months) groups (p<0.001). After controlling for patient age, race, insurance status, presence of comorbid conditions, brachytherapy use, and disease stage, compared to same-day chemotherapy initiation, patients who received chemotherapy within one week (HR: 1.07, 95% CI: 1.01-1.14), 1-2 weeks (HR: 1.14, 95% CI: 1.01-1.28) or 2-3 weeks (HR: 1.32, 95% CI: 1.12-1.57) after radiotherapy initiation had worse overall survival. <b>Conclusions:</b> Any delay in administering radio-sensitizing chemotherapy relative to radiotherapy initiation may be associated with a detrimental effect on the survival of patients with LACC, especially for those with stage III-IVA disease. Same-day initiation of chemotherapy with radiation should be encouraged.