Background: Platinum-based chemotherapy associated with cetuximab is the first-line treatment for inoperable recurrence or metastatic head and neck squamous cell carcinoma (HNSCC). There is no established biomarker for cetuximab efficacy in HNSCC. The PI3K pathway is one of the most frequently altered pathways in HNSCC. Loss of phosphatase and tensin homolog (PTEN) expression occurs in up to 30 % of cases.
Methods: This was a retrospective analysis of data from 61 patients with inoperable recurrence or metastatic HNSCC treated with cetuximab. PTEN, epidermal growth factor receptor and p16 expression were analyzed by immunohistochemistry and tested for association with clinical outcomes.
Results: Median overall survival was 11.4 months and progression-free survival was 6.9 months. Low PTEN expression was present in 26.2 % of patients and identified patients with worse prognosis. p16 was positive in only 8.5 % of tumors.
Conclusions: Low PTEN expression in patients treated with cetuximab plus chemotherapy emerged as a prognostic biomarker and should be evaluated for its predictive role for cetuximab efficacy.