Prognostic significance of the expression of immunohistochemically detectable differentiation markers in laryngeal carcinomas.

Expression of immunocytochemically detectable markers in 100 cases of laryngeal carcinomas, homogeneous for staging and treatment, was correlated with clinical evolution of the disease. Follow-up for a minimum of 5 years was obtained in all cases. Paraffin sections were re-cut and stained in immunoperoxidase with monoclonal KL1, detecting medium-to-low molecular weight keratins, and with monoclonal HMFG2, revealing a surface glycoprotein. Expression of KL1-related antigen did not correlate with prognosis, whereas cases extensively positive for monoclonal HMFG2 (more than 50% cells stained) had a significantly better recurrence-free rate. In a group of tumors classified as Grade 3 (histologically poorly differentiated) and expressing a low degree of HMFG2-detectable surface glycoprotein (less than 50% cells stained), a high rate of recurrences (93%) was observed. This study indicates that the combined use of morphologic and biologic (immunohistochemical) criteria may constitute an independent parameter of primary importance in predicting the evolution of laryngeal carcinomas.