Prognostic value of CD44 variant 6 in laryngeal epidermoid carcinomas

CD44 variant exon 6 (v6) belongs to a family of transmembrane glycoproteins involved in cell adhesion.

To determine the prognostic role of CD44v6 in laryngeal cancer and to examine its relation with other clinicopathologic prognostic factors.

A retrospective cohort study was designed with 93 laryngeal cancer cases. They were selected randomly from patients treated with laryngectomy between January 1, 1983, and December 31, 1993.

Faculty of Medicine, Hacettepe University, Ankara, Turkey.

The ages of the patients ranged from 31 to 73 years. Eighty-eight patients were men and 5 were women. Three had stage I, 33 had stage II, 27 had stage III, and 30 had stage IV disease at the time of surgery.

Histological sections of tumors and metastatic lymph nodes were reevaluated for several histopathological factors. Sections were stained using anti-CD44v6 monoclonal antibody by immunohistochemical methods.

CD44v6 expression was seen only in the lower one third of the normal squamous epithelium but in all layers of dysplasia and in situ carcinoma. Besides a general evaluation of tumor staining, immunostaining was evaluated separately for cell groups located in the center of neoplastic islands (nonbasal cells), at the periphery of the neoplastic islands (basal cells), and at the infiltration zones (marginal cells). Decreased disease-free survival was noted when there was extensive staining in the general evaluation and in cases with extensive staining in marginal and nonbasal cells (P =.03). Using Cox regression analysis, the greatest dimension of the largest metastatic lymph node and extensive expression of CD44v6 in nonbasal tumor cells were independent prognostic factors.

Our results suggest that CD44v6 expression is an important prognostic factor in laryngeal cancer.