Multicenter prospective phase II trial of concurrent chemoradiotherapy with weekly low-dose carboplatin for cisplatin-ineligible patients with advanced head and neck squamous cell carcinoma

Background: The optimal chemotherapy regimen in concurrent chemoradiotherapy (CCRT) for cisplatin-ineligible head and neck squamous cell carcinoma (HNSCC) has not been established. We aimed to evaluate the feasibility, efficacy, and safety of CCRT with weekly low-dose carboplatin for the treatment of advanced HNSCC in patients who are cisplatin-ineligible.

Methods: This prospective phase II study enrolled adult patients (age ≥ 20 years) with HNSCC receiving whole-neck irradiation including bilateral levels II-IV and who were aged (≥ 75-year-old patients with 40 mL/min estimated glomerular filtration rate [eGFR] or better) or had renal dysfunction (< 75-year-old patients with 30-60 mL/min eGFR). Carboplatin was administered weekly (area under the plasma concentration-time curve = 2.0) for up to seven cycles during concurrent radiotherapy (70 Gy/35 Fr). The primary endpoint was the completion rate of CCRT. Secondary endpoints included overall response rate and incidence of adverse events.

Results: Among the 30 patients enrolled, 28 were men. The median age was 73.5 years. Seventeen patients were < 75 years whereas 13 were ≥ 75 years old. The completion rate of CCRT was 90%. The overall response rate was 90%. Grade 3 adverse events that occurred in 10% or more patients were oral/pharyngeal mucositis (47%), leukocytopenia (20%), and neutropenia (10%). Grade 4 adverse events occurred in one patient (elevation of alanine aminotransferase level). No treatment-related deaths occurred.

Conclusion: CCRT with weekly low-dose carboplatin is a promising treatment option, with favorable feasibility, efficacy, and acceptable toxicity, for patients who are cisplatin-ineligible with advanced HNSCC.

Clinical trial registration number: jRCTs031190028.