Cetuximab-induced rash is associated with overall survival in patients with recurrent/metastatic squamous cell carcinoma of head and neck.

Purpose: In this study, we looked for whether treatment-induced rash predicts treatment efficacy in patients with recurrent/metastatic HNSCC treated with Cetuximab and chemotherapy.

Methods: Patients who were treated with platinum-based chemotherapy and cetuximab for the first line treatment of recurrent/metastatic HNSCC were recruited. Presence of rash, hypomagnesemia, hypopotassemia, anemia, neutropenia, thrombocytopenia during treatment and treatment response, date of progression, date of last visit and death were recorded.

Results: A total of 138 patients' data were available for analysis. Any grade of rash was detected in 57 (44.5%) of the patients. The incidence of rash was significantly higher in patients with objective response than in patients with disease progression (%56.8 vs %14.3, p < 0.001). Progression free survival was 7.06 months (4.98-9.15) in patients treated with cetuximab and chemotherapy as first line treatment. In the multivariate analysis; rash was significantly correlated with longer PFS (HR 2.136; 95% CI 1.067-4.278; p = 0.032). Progression free survival was 9.65 months in patients who experienced rash, and 6.02 months in patients without rash, (p = 0.019, log-rank test). Overall survival was 11.24 months (9.65-12.82). In multivariate analysis, the survival of patients with rash was significantly longer than patients without rash (HR 1.954; 95% CI 1.162-3.285; p = 0.012). Overall survival was 15.08 months in patients who experienced rash, and 8.61 months in patients without rash (p = 0.05, log-rank test).

Conclusion: Cetuximab-induced rash is associated with better ORR and longer PFS and OS in patients with recurrent/metastatic HNSCC treated with Cetuximab and platinum-based chemotherapy.