職業性尿路腫瘍の背景と現況

Abstract

1) Benzidineおよびbeta-naphthylamine曝露症例231例中15例(6.5%)の尿路上皮癌の発生を認めた.2)尿路上皮腫瘍発生までの潜在期間は初期曝露より平均28.8年, 最終曝露より平均16.6年であった.3)曝露期間と曝露終了後からの潜在期間に負の相関が認められた.4)初診時点における尿細胞診は60%において陽性所見が認められ, 曝露症例における定期的尿細胞診の必要性が示された.5)膀胱洗浄液標本あるいは腫瘍組織のflow cytometric DNA histogram (FCM)の検討において全例にaneuploidyが認められた.またFCMは尿細胞診に先んじてその異常を呈する可能性を認めた.6)膀胱保存的治療を施行した55%に腫瘍の再発を認めた.また全症例において平均8.6年の経過観察で20%の症例が癌死した.7) 2例において肝臓癌, S字状結腸癌の重複癌の発生が認められた

The incidence of urothelial cancers in a group of 231 dyestuff plant workers who had been exposed to benzidine (BZ) or to beta-naphthylamine (BNA) was surveyed from 1962 to 1988. Fifteen out of 231 patients (6.5%) were found to have bladder cancer with the mean age at onset of 57.1 +/- 8.7 years. The estimated average period of engaging in this dyestuff exposure for these 15 patients was 92.4 +/- 47.3 months. The mean latent periods from the initial and last exposure until tumor development were 28.8 +/- 5.7 years and 16.6 +/- 7.0 years, respectively. Good negative correlation was observed between exposure periods and latent periods from the last exposure to onset (R = -0.06814). All 15 patients demonstrated tumors in the bladder, and one patient had a metachronous upper urinary tract cancer after treatment for bladder cancer. All tumors were histologically transitional cell carcinomas except for one adenocarcinoma. For initial treatment, five underwent total cystectomy, eight had transurethral resection (TUR) of the tumor, and one had partial cystectomy. Five out of 8 patients who had TUR have developed recurrent bladder tumors, and two of those patients underwent total cystectomy for second treatments. The mean follow-up period was 8.6 +/- 5.2 years, with two dying of cancer. For detection and monitoring, flow cytometric (FCM) analyses were available in five cases with bladder tumor and in two follow-up cases after bladder preserving treatments.(ABSTRACT TRUNCATED AT 250 WORDS)