Abstract
The purpose of this study was to evaluate the clinicopathological effects of neoadjuvant chemotherapy (NAC) for lymph node metastasis in patients with locally advanced hypopharyngeal cancer. Methods：① The clinical response was compared between the NAC and non-NAC groups. ② The relationship between the clinical response and the pathological response was evaluated. ③ The relationship between the size of the histopathologically NAC effective (fibrotic change) area and the prognosis was examined. ④ Large cross-section specimens were obtained from nine patients, and the detailed findings of lymph node metastasis were examined. Results：① The survival and distant metastasis control rates in the NAC group were superior to those observed in the non-NAC group. ② The clinical and pathological responses were generally consistent. ③ The 5-year survival rate was 100% in the patients whose examined tissues contained more than 50% fibrosis and 43% in the patients who tissues contained less than 50% fibrosis. These results indicate that patients who exhibit a good response to NAC achieve a better prognosis. ④In some specimens, histopathological invasion of cancer cells was often observed in the extracapsular adipose and vascular tissue. These findings suggest that both the clinical and pathological responses to NAC are indications of a better prognosis. Examining large cross-section specimens and quantifying the percentage of fibrosis in the extracted tissues is a possible histopathological method for identifying patients with a better prognosis.
