P2-9-10 - A study of chemoradiotherapy with high dose cisplatin for postoperative high-risk squamous cell carcinoma of oral cavity

Abstract

Background: CCRT is a standard treatment for locally advanced oral cavity squamous cell carcinoma(OSCC). However some patients cannot tolerate high dose density of cisplatin. In this study, we investigate the predictive factors that affect the completion of the CCRT. Methods: We retrospectively analyzed postoperative high-risk OSCC patients treated with CCRT with CDDP (100mg/m2 per 3 weeks) from April 2011 to December 2014 in Tokai University hospital. Radiation therapy was performed as three-dimensional radiotherapy. Results: A total 40 patients (29 male, 11 female; median age 67 years) received CCRT, primary sites were as follows; tongue 21, mandibular gingiva 8, maxillary gingiva 5, palate 2, buccal mucosa 2, oral floor 1, intraosseous of Mandible 1. Of 40 patients studied, 27 patients completed the postoperative CCRT, a completion rate of 67.5%. As for CDDP treatment, 27 (67.5%) patients completed 3 cycles of CDDP, 9 (22.5%) patients received 2 cycles, and 4 (10%) patients received only 1 cycle. Grade 3 and more severe adverse events, as evaluated according to CTCAE Version 4.0 were as follows; leucopenia 21 (52.5%), neutropenia 11 (27.5%), nausea 18 (45%), oral mucositis 6 (15%), febrile neutropenia 6 (15%). The main reason for CDDP discontinuation were hematological toxicity (6 patients) and renal dysfunction (4 patients). In logistic regression analysis, renal function (eGFR < 73) and neutropenia (Grade3 and more) were associated with CDDP discontinuation (p = 0.034, p = 0.015, respectively). Conclusions: In CCRT to OSCC patients, 27 patients completed the postoperative CCRT, a completion rate of 67.5%. Renal function and neutropenia are significant as predictive factors of CDDP discontinuation.