The impact of conventional morphologic analysis on response rates and survival in patients with advanced head and neck cancers treated initially with cisplatin-containing combination chemotherapy.

The response to initial treatment with cisplatin-containing combination chemotherapy as well as survival, were correlated with tumor differentiation (well, moderate or poorly differentiated) in 164 patients with advanced, untreated squamous cell carcinoma of the head and neck. Thirty-three percent of the tumors were graded as poorly differentiated, 59% moderately differentiated, and 8% were well differentiated. The overall clinical response rates were nearly equal for the three grades of differentiation: 79% for well differentiated, 86% for moderately differentiated, and 89% for poorly differentiated. The complete response rate was somewhat higher for poorly differentiated tumors: 46% as compared to 32% and 29% for moderately and well differentiated respectively, but the differences were not statistically significant. The median survival for each morphologic group was 22, 16, and 12 months for well differentiated, moderately differentiated and poorly differentiated tumor, respectively (P = 0.097). For patients achieving a complete clinical response to chemotherapy, there was a difference in survival when stratified according to degree of histologic differentiation. Patients who were complete responders and had well or moderately differentiated tumors attained 75% and 38% survival at 36 months, respectively, versus 19% for patients with complete response and poorly differentiated tumors (P = 0.064). The degree of differentiation of previously untreated squamous cell cancers of the head and neck does not conclusively predict tumor response to combination chemotherapy, but may reflect differences in natural history. Survival is improved in patients with differentiated tumors as compared to those with poorly differentiated tumors. Morphologic grading in patients achieving a complete response reveals a decrease in survival for patients with poorly differentiated tumors.