Phase I study of concurrent selective lymph node late course accelerated hyper-fractionated radiotherapy and pemetrexed, cisplatin for locally advanced esophageal squamous cell carcinoma.

The optimized concurrent chemoradiotherapy has not been established for patients with advanced esophageal squamous cell carcinoma (SCC). The aim of the present study was to evaluate the safety and efficacy of concurrent chemotherapy and selective lymph node (SLN) late course accelerated hyperfractionated (LCAF) intensity modulated radiotherapy (IMRT) for the patients with thoracic SCC. Twelve patients with T3-4N0-1M0-1a thoracic esophageal SCC were included. The total dose of SLN LCAF IMRT was 59.6 Gy/34 fractions in 5.4 weeks. The concurrent chemotherapy protocol was as following: cisplatin 10 mg/m(2) on days 1-5 and 22-26, pemetrexed in escalating doses, from the base level of 500 mg/m(2) once every 21 days. The primary objectives were to determine the maximum tolerated dose (MTD), recommended dose (RD), and dose limiting toxicities (DLTs). Secondary end point included determination of preliminary radiographic response rates. As a result, three patients were enrolled in dose level 1 with pemetrexed 500 mg/m(2) and nine patients in dose level 0 with 400 mg/m(2) , respectively. At dose level 1, DLTs occurred in two of three patients. However, only two of nine patients in Level 0 developed DLTs. The complete response and partial response were observed in eight and four patients, respectively. Furthermore, no patient experienced cancer progression with a median follow-up of 9 months. In conclusion, the concurrent SLN LCAF IMRT and chemotherapy is feasible. The MTD of pemetrexed in this regimen was 500 mg/m(2) and RD was 400 mg/m(2) . Although toxicities were common, the protocol was safe, well tolerated, and achieved an encouraging outcome.