S-589 Comparison of of three-weekly versus weekly cisplatin in concurrent chemoradiation for LA-HNSCC

Introduction: Standard treatment for locally advanced (stage III-IV) head and neck squamous cell cancer (LA-HNSCC) is concurrent chemoradiation therapy (CCRT) with cisplatin 100mg/m2 every three weeks. For medically unfit patients susceptible to treatment-related adverse events, low-dose weekly cisplatin can be used as an alternative. In previous studies, weekly cisplatin-based regimen showed fair efficacy and tolerable toxicity profiles. In this study, we retrospectively compared the therapeutic outcomes of low-dose weekly cisplatin regimen and standard regimen in CCRT for LA-HNSCC.?Methods: The medical records of histologically confirmed LA-HNSCC patients were retrospectively reviewed from Jan 1, 2007 to Dec 31, 2012. 224 patients who were treated with CCRT as initial treatment were enrolled. Among them, 155 patients were treated with low-dose (30 mg/m2) weekly cisplatin and 69 patients were treated with standard-dose (100 mg/m2) three-weekly. Dose intensity of cisplatin in each group was calculated as proportion of delivered dose in full regimen dosage.?Results: Baseline characteristics of both groups did not differ significantly, except that standard-dose group contained more larynx cancer patients. Although dose intensity of standard-dose cisplatin group (84%) were lower than low-dose weekly cisplatin group (91%), difference in median progression free survival (31.2 month vs 26.3 month; p＝0.469) and overall survival (36.6 month vs 31.6 month; p＝0.439) was not statistically significant between standard-dose group and low-dose group.?Conclusions: In the present study, low-dose weekly cisplatin was not inferior to standard-dose cisplatin in terms of survival outcomes. Prospective comparison of standard-dose three-weekly and low-dose weekly cisplatin is warranted.