舌進展癌に対する術前化学放射線同時併用療法の効果と縮小手術の適応に関する臨床病理学的研究

Abstract

Forty patients who received chemoradiotherapy followed by surgery for advanced tongue carcinoma were studied clinically and histopathologically, and the minimally invasive treatment for advanced tongue carcinoma was evaluated. 1. Clinical effects on the primary tumor were CR in 22(55.0%), PR in 15(37.5%), and NC in 3(7.5%). The CR rate was nearly 60%, and the overall response rate was 92.5 % ; the treatment was highly effective. 2. Histological effects on the primary tumor were Grade Ⅱb or above, i.e. effective, in 31(8.6%), and Grade Ⅳ, i.e. pathological CR, in 18(51.4%). The treatment was also very effective histologically, and a correlation was observed between clinical effects and histological effects. 3. Concerning the relationship between histological effects and the regression rate, a regression rate of 85% or higher was needed to obtain a histological effect of Grade Ⅱ b or above, and a regression rate of 95% or higher was needed to obtain a histological effect of Grade Ⅲ or above. 4. Investigation of residual tumors showed persistence of cancer cells primarily in the center of the tumor, but both the horizontal and vertical residual rates were low, and cancer cells tended to be limited to the superficial layer of the central area of the primary tumor in the patients who showed a regression rate of 85% or higher. 5. Histopathological malignancy, tumor vessel density(CD 31), and p53 were suggested to be potential predictive factors of the effectiveness of preoperative therapy. 6. The residual tumor Grade (R Grade) in the resected specimen is considered to be useful as a prognostic factor after resection of the primary tumor. 7. Histological effects were also satisfactory in patients who showed a clinical effect of 85% or higher on this preoperative therapy. In such patients, minimum invasive surgery is considered to be applicable even in advanced cases, and improvements in the postoperative QOL are expected by oral organ/function preservation.