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 LA-HNSCC. However, its efficacy when compared to HD-DDP + RT has been questioned. At our institution, low-dose weekly carboplatin is added to cetuximab + RT for pts unsuitable for HD-DDP. Methods: We reviewed records of 16 pts with LA-HNSCC treated with definitive Cx + carboplatin + RT at the University of Miami from 2007-2011. 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, N2a=2, N2b=1. All pts 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 pts, there were: 12 CR, 2 PR, and 1 PD. There were 3 local in-field failures, 2 regional failures, and 3 distant failures. At last follow-up, 8/15 pts remained with NED. 3-year locoregional recurrence was 28.3% (95% CI: 7.7%-53.9%). Mean percentage of weight loss was 14% (range: 6-26%). Two pts required systemic therapy dose-reduction. Three pts experienced a treatment delay and 3 did not finish RT as planned including a pt who received only 30Gy due to death secondary to MI during treatment. Conclusions: In this small retrospective series, carboplatin/Cx/RT was well-tolerated and efficacious in pts 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 pts who are poor candidates for more aggressive therapies and warrants evaluation in a prospective manner.