Concurrent radiotherapy with carboplatin and cetuximab for the treatment of medically compromised patients with locoregionally advanced head and neck squamous cell carcinoma

Background: Cetuximab (Cx) + radiation therapy (RT) is well-tolerated and has improved survival in patients (pts) with locoregionally advanced head and neck squamous cell carcinomas (LA-HNSCC). However, its efficacy when compared to HD-DDP + RT has been questioned. At our institution, low-dose weekly carboplatin is added to Cx + RT for patients unsuitable for HD-DDP. Methods: We reviewed records of 16 patients with LA-HNSCC treated with definitive Cx + carboplatin + RT at the University of Miami from 2007 to 2011. Median follow-up was 24 months (range: 1-69 months). Results: Median age: 71.5 years (range: 57-90 years); 15 male, 1 female. ECOG PS 0 = 15, 1 = 1. TNM staging was: T₁ = 1, T₂ = 5, T₃ = 8, T₄ = 2; N stage: N0 = 8, N₁ = 5, N_2a = 2, N_2b = 1. All patients received weekly carboplatin (AUC 1.5-2), Cx given conventionally and daily conventionally fractionated RT. Median total weeks of concurrent systemic therapy = 7 (range: 3-8 weeks). RT was delivered to a median total dose of 70 Gy (range 30-74 Gy). Of the 15 evaluable patients, there were: 12 CR, 2 PR, and 1 PD. There were three local in-field failures, two regional failures, and three distant failures. At last follow-up, 8/15 patients remained with NED. Three-year locoregional recurrence was 28.3% (95% CI: 7.7-53.9%). Mean percentage of weight loss was 14% (range: 6-26%). Two patients required systemic therapy dose reduction. Three patients experienced a treatment delay and three did not finish RT as planned including a patient who received only 30 Gy due to death secondary to MI during treatment. Conclusion: In this small retrospective series, carboplatin/Cx/RT was well-tolerated and efficacious in patients unsuitable for HD-DDP having LA-HNSCC. Acute toxicities were similar to Cx + RT, likely due to the non-overlapping toxicity profiles of the two systemic agents. We hypothesize that the addition of a well-tolerated cytotoxic chemotherapy agent may improve the therapeutic ratio of Cx + RT in patients who are poor candidates for more aggressive therapies and warrants evaluation in a prospective manner.