ERCC1, p16, and Ki-67 immunohistochemichal expression as predictive and prognostic markers in head and neck squamous cell carcinoma treated with platin-based induction chemotherapy: Staining with the two anti-ERCC1 antibodies (8F1 and FL-297) was compared.

Abstract

e13578 Background: Head and neck squamous cell carcinoma (HNSCC) treatment had undergone important changes, in particular due to the organ preservation and the advent of chemotherapy, particularly using platinum. The excision repair cross-complementation group 1 (ERCC1) enzyme plays a rate-limiting role in the nucleotide excision repair pathway and has been associated with resistance to platinum-based chemotherapy. The purpose of this study was to evaluate the role of ERCC1expression with p16 and Ki-67 as predictive markers in the response to platin-based induction chemotherapy and as prognostic markers in patients with HNSCC. Methods: 208 patients treated from 2000 to 2006 by an induction chemotherapy regimen for HNSCC were included retrospectively. ERCC1 (8F1 and FL297 clone), p16 and Ki-67 staining were performed on paraffin-embedded tumor tissue collected before chemotherapy. We assessed response to treatment, progression-free survival (PFS) and overall survival (OS). Results: Respectively, 68% (142/208 patients) and 81.5% (163/200 patients) of HNSCC showed low expression of 8F1 and FL297 ERCC1. No correlation was found between the two clones (p=0.1). There was no correlation between the expression of 8F1 ERCC1, FL297 ERCC1 and Ki-67 and the response to induction chemotherapy, OS or PFS. However, in the subgroup of 129 patients treated with induction cisplatin-5FU chemotherapy, a low expression of 8F1 ERCC1 was significantly associated with a better response (p=0.027). Over expression of p16, found in 34.5% of cancers of the oropharynx was significantly correlated with a better OS (p=0.0007) and a better PFS (p = 0.01). Conclusions: These results suggest that ERCC1 expression might be a useful predictive marker of HNSCC in patients treated by cisplatin-based chemotherapy. The 8F1 ERCC1 clone appears to be the best for immunohistochemical analysis; clone FL297 did not show any association with treatment response and survival. Independently, our study confirms the prognostic value of the over expression of p16 in carcinoma of the oropharynx.