Efficacy and Tolerance of Carboplatin plus Cetuximab (Simplified EXTREME Regimen) in Patients with Recurrent and/or Metastatic Head and Neck Squamous Cell Carcinoma.

Aims: The EXTREME regimen is the standard for recurrent and/or metastatic head and neck squamous cell carcinoma (HNSCC). However, many patients have a poor performance status and/or comorbidities, making them unfit for this regimen. We have treated them with carboplatin and cetuximab (simplified EXTREME regimen) since 2007. Our aim was to assess the efficacy and tolerance of this regimen in this frail population.

Materials And Methods: A retrospective chart review of all patients treated with the simplified EXTREME regimen for recurrent and/or metastatic HNSCC in three academic hospitals between 2007 and 2017 was carried out. The primary end point was overall survival. Secondary end points were progression-free survival (PFS), overall response rate (ORR) and toxicity.

Results: One hundred and three patients were included. The median age was 63 years, 40% had performance status 2-3. The median follow-up was 30.2 months. The median overall survival and PFS were 7.2 and 3.7 months, respectively. The median overall survival was 10.1 months in patients with performance status 0-1 versus 4.6 months in patients with performance status 2-3 (P = 0.01). ORR was 39%. Acute grade 3-4 haematological and non-haematological toxicity rates were 25.2% and 27.2%, respectively. Patients with grade 1 or more skin toxicity had a higher ORR (hazard ratio = 3.44; P = 0.03), a prolonged overall survival (hazard ratio = 0.37; P < 0.0001) and PFS (hazard ratio = 0.29; P < 0.0001). During treatment, 29% of patients had pain reduction, 13.5% had weight gain and 17.2% had an improvement in performance status.

Conclusions: This is the largest cohort of patients treated with simplified EXTREME for HNSCC. It was well tolerated, with a high ORR. Interestingly, skin toxicity correlated with treatment efficacy.