667P - Definitive concurrent chemoradiotherapy using S-1 in the treatment of elderly patients with esophageal cancer

Abstract

Definitive concurrent chemoradiotherapy (CCRT) with 5-florouracil (5-FU) and cisplatin (CDDP) are often associated with signifiant incidence of toxicities in elderly patients with esophageal cancer. This reteospective study was aimed at investigating the efficiency and safety of using S-1 as mono and maintenance therapy combined with concurrent radiotherapy (RT) for elderly patients with esophageal cancer. From January 2009 to December 2010, 68 (aged over 70 years) elderly patients were included. RT was delivered with a daily fraction of 1.8-2.0Gy to a total radiation dose of 54.0-60.0Gy using the three-dimensional conformal technique (3D-CRT). Preplanned concurrent S-1 (80mg/m2/day) was given on Days 1-14, every 3 weeks. After concurrent chemoradiotherapy (CCRT), maintenance S-1 was repeated up to four cycles. The median age was 76 years (range: 70-88 years), and the clinical stages were stage I (two patients), stage II (24 patients), stage III (28 patients), and stage IV (14 patients). 51 (75.0%) patients finished treatment on schedule and the median cycles of S-1 was five, of which 35 (51.5%) patients achieved complete response. The median follow-up time was 42.7 months, and the median overall survival (OS) and progression-free survival (PFS) time were 25.7 and 21.5 months, respectively. The 1- and 3-year OS and PFS rates were 70.6%, 41.8% and 68.1%, 32.9%, respectively. Grade ≥3 neutropenia and leukopenia were found in 14 and 13 patients, respectively. The most common non-hematologic toxicity was esophagitis including six and one patients with grade 3 and 4. For elderly patients with esophageal cancer, S-1 as mono and maintenance chemotherapy in combination with RT could improve survival outcomes with tolerable toxicities. More clinical trials (like NCT02716688) are highly warranted to further clarify this issue.