根治的膀胱全摘除術を施行した膀胱癌症例における予後因子の解析と術後補助化学療法の有効性の評価

Abstract

根治的膀胱全摘除術を施行した膀胱癌71例について予後に関与する因子を多変量解析を用いて検討した.今後に影響を及ぼす因子として深達度・手術時期・リンパ節転移が重要であった.術後補助化学療法(PPM療法)は, 深達度・リンパ節転移の二つの主要要因により補正した場合にPPM施行症例では非施行症例に比べて予後に関してやや有利な状態をもたらす可能性が示唆された

Multivariate analysis by Cox's proportional hazard model was performed on 71 bladder cancer patients treated by radical cystectomy to clarify factors affecting survival and to evaluate the efficacy of postoperative adjuvant chemotherapy. Clinicopathologic data included in the analysis were age, sex, interval from onset of symptoms to first consultation, prior tumor history, year of operation and tumor characteristics: size, number, growth pattern, stage, grade, mode of infiltration, lymphatic invasion, lymph-node metastasis and lymphocyte infiltration around tumors. Analysis revealed that stage is the most statistically significant factor for survival (p less than 0.0001); followed by year of operation (p less than 0.05) and lymph node metastasis (p less than 0.1). The above three determinants yielded hazard ratios of 16.6 for stage (pT3a-pT4 vs. pTis-pT2), 2.7 for year of operation (1978-1982 vs. 1983-1987) and 2.4 for lymph node metastasis (positive vs. negative). Postoperative adjuvant chemotherapy consisting of cisplatin, peplomycin and mitomycin C (PPM therapy) seemed to improve survival, when the influence of the major prognostic factors were adjusted by the proportional hazards model. The authors conclude that stage and lymph node metastasis should be considered when postoperative adjuvant treatment is selected for patients with bladder cancer treated by radical cystectomy, and that further prospective randomized trials are mandatory to confirm the efficacy of postoperative adjuvant PPM therapy suggested by the present retrospective multivariate analysis.