Background: It is shown that the postoperative adjuvant chemotherapy for non-small cell lung cancer (NSCLC) was associated with survival benefit in an elderly population. We aimed to analyze the feasibility and efficacy of alternate-day S-1, an oral fluoropyrimidine, for adjuvant chemotherapy in elderly patients with completely resected pathological stage IA (tumor diameter > 2 cm) to IIIA (UICC TNM Classification of Malignant Tumours, 7th edition) NSCLC.
Methods: Elderly patients were randomly assigned to receive adjuvant chemotherapy for one year consisting of either alternate-day oral administration of S-1 (80 mg/m2/day) for 4 days a week (Arm A) or a daily oral administration of S-1 (80 mg/m2/day) for 14 consecutive days followed by 7-day rest (Arm B). The primary endpoint was feasibility (treatment completion rate), which was defined as the proportion of patients who completed the allocated intervention for 6 months with a relative dose intensity (RDI) of 70% or more.
Results: We enrolled 101 patients in which 97 patients received S-1 treatment. The treatment completion rate at 6 months was 69.4% in Arm A and 64.6% in Arm B (p = 0.67). Treatment completion rate in Arm B tended to be lower compared to Arm A, as the treatment period becomes longer (at 9 and 12 months). RDI of S-1 at 12 months and completion of S-1 administration without dose reduction or postponement at 12 months was significantly better in Arm A than in Arm B (p = 0.026 and p < 0.001, respectively). Among adverse events, anorexia, skin symptoms and lacrimation of any grade were significantly more frequent in Arm B compared with Arm A (p = 0.0036, 0.023 and 0.031, respectively). The 5-year recurrence-free survival rates were 56.9% and 65.7% for Arm A and B, respectively (p = 0.22). The 5-year overall survival rates were 68.6% and 82.0% for Arm A and B, respectively (p = 0.11).
Conclusion: Although several adverse effects were less frequent in Arm A, both alternate-day and daily oral administrations of S-1 were demonstrated to be feasible in elderly patients with completely resected NSCLC.
Trial registration: Unique ID issued by UMIN: UMIN000007819 (Date of registration: Apr 25, 2012) https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000009128. Trial ID issued by jRCT: jRCTs061180089 (Date of registration: Mar 22, 2019, for a shift toward a "specified clinical trial" based on Clinical Trials Act in Japan) https://jrct.niph.go.jp/en-latest-detail/jRCTs061180089.
Copyright: © 2023 Yamamoto et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.