Outcomes of Definitive Chemoradiotherapy for Stage Iva (T4b Vs N4) Esophageal Cancer Based on the Japanese Classification System: A Retrospective Single-center Study 

Abstract

Background: Based on the Japanese classification of esophageal cancer, Stage IVa involves locally advanced T4b disease and/or lymphatic spread (N4). Stage IVa disease is generally treated using chemoradiotherapy (CRT) for patients in good condition. However, it is unclear whether there are differences in prognoses or progression patterns between T4b non-N4 and non-T4b N4 cases. This study compared the outcomes of CRT for Stage IVa esophageal cancer according to T/N factors.Methods: We retrospectively identified 68 patients with Stage IVa esophageal cancer who underwent definitive CRT at our center between January 2009 and March 2013. The patients’ medical records, diagnostic images, and radiation plans were reviewed, as well as their treatment outcomes, progression patterns, prognostic factors, and toxicities evaluated based on version 5.0 of the National Cancer Institute Common Terminology Criteria for Adverse Events.Results: The 68 patients (58 men and 10 women) included had a median age of 67 years (range: 37–87 years). The histological classifications were squamous cell carcinoma (66 patients), adenocarcinoma (one patient), and verrucous carcinoma (one patient). The T/N classifications were T4b non-N4 (29 patients), non-T4b N4 (25 patients), and T4b N4 (14 patients). Local control (complete or partial response) was achieved in 58 patients (85%). The median overall survival was 13 months (2-year rate: 32.1%) and the median progression-free survival was 7 months (2-year rate: 16.4%). We did not manage to detect significant differences between the T/N groups in terms of overall survival, progression-free survival, and progression pattern. Multivariate analyses revealed that independent prognostic factors were nadir hemoglobin and nadir albumin during the CRT period, as well as performance status at CRT initiation. Grade 3 or worse toxicities were observed in 55 patients (81%), and five patients died because of treatment-related adverse events.Conclusion: At our center, there were no significant differences in prognoses or progression patterns among patients with T4b non-N4, non-T4b N4, and T4b N4 esophageal cancer. Thus, it seems impractical to modify CRT regimens based on T/N factors, and delivering sufficient doses of both radiotherapy and chemotherapy is important for adequately treating Stage IVa esophageal cancer regardless of T/N factors.