Comparison of the Effect of Weekly Cisplatin Versus Three Weekly Cisplatin in Concurrent Chemoradiotherapy of Head and Neck Cancer: A Pilot Study.

Patients with squamous cell carcinoma of the head and neck (HNSCC) often present with advanced locoregional disease. Combined modality treatment with definitive concurrent chemoradiotherapy (CTRT) has become the standard of care for these cancers. We compared the efficacy and toxicity profile of weekly cisplatin regime compared to a three-weekly cisplatin regime in the setting of definitive CTRT for locally advanced HNSCC (LAHNSCC). 51 patients were enrolled in the study between May 2016 and June 2019. In arm A, 25 patients (n = 25) were given three weekly cisplatin at dose of 100 mg/m2 on days 1, 22 and 43 (D1, D22, D43) concurrent with radiotherapy. In arm B, 26 patients (n = 26) were given weekly cisplatin at dose of 35 mg/m2. Primary end points of the study were locoregional control (LRC), distant metastasis free survival (DMFS) and disease free survival (DFS). Adverse effects / toxicity was the secondary end point. Out of the 51 total patients, 49 patients underwent response evaluation at 3-month follow up, after completion of definitive CTRT. Two patients expired in the 3 weekly cisplatin arm before response assessment. On MRI, total 29 patients had complete clinicoradiologic response (cCR), 14 in weekly cisplatin arm and 15 in three weekly cisplatin arm. Only these 29 patients showing cCR were eligible for evaluation of LRC, DMFS and DFS at 2 years. Median follow up period was 20 months. At the time analysis 1 patient in 3 weekly arm and 2 patients in weekly arm expired. All of them had disease relapse during follow up. After 2 years of follow up, overall 89.7% (n = 26) patients had LRC. 92.86% (n = 13) in 3 weekly arm and 86.15% (n = 13) in weekly arm had LRC after 2 years. DMFS at 2 years was 86.15% (n = 13) in 3 weekly arm in comparison to 78.57% (n = 11) in weekly arm. DFS at 2 years was 77.92% (n = 11) in 3 weekly arm versus 66.67% (n = 10) in weekly arm. LAHNSCC patients with ECOG PS of 0-2, should be offered 3 weekly cisplatin regime in the setting of definitive CTRT as preferred regime in comparison to weekly cisplatin in view of trend favoring better response in terms of LRC, DMFS and DFS. Acute toxicities are more common in 3 weekly cisplatin arm as compared to weekly cisplatin arm but most of the toxicities are grade 1 or 2 which can be easily managed. This is a pilot study and randomized trials are needed to confirm the findings.