長期経過観察したHNPCCの1例

A Long-term Follow-up Case of HNPCC

要旨　24年の経過を追えたHNPCCの1例を経験した。56歳の女性．家族歴は母親と2人の異父兄弟および長男が大腸癌．ほかに母方の血縁に胃癌3人，卵巣癌3人．既往歴は40歳時（1972年），盲腸癌で回盲部切除を受けている．1988年，右側横行結腸進行癌の診断で右半結腸切除術を施行し，1型，2型進行癌とⅡa型m癌を認めた．次いで1991年，残った横行結腸に2個の2型進行癌とLST（sm癌）を認め，横行結腸切除術を施行した．その後1993年，S状結腸にLSTを認め腹腔鏡補助下にS状結腸切除術を施行し，結果はsm癌であった．以後外来で年数回の大腸内視鏡による経過観察を行っているが，現在のところ新たな癌の発生は認めていない．

　A case of HNPCC (hereditary nonpolyposis colorectal cancer) was follewed up for 24 years. During that time eight colon cancers were generated. The patient was 56 years old when she visited our hospital. As past history, she had experienced a cecal cancer (No.1) and ileocecal resection had been performed at the age of forty.

　Her pedigree included five patients with colon cancer (including this patient), three patients with gastric cancer and two patients with ovarian cancer (Fig. 1). Three successive generations had had colon cancer in her family.

　She visited our hospital complaining of abdominal fullness in the age of 56. Advanced cancer was detected in her transverse colon by colonoscopy. Right hemicolectomy was performed, and two advanced cancers and one intramucosal cancer were detected. Three years later, advanced colon cancer was detectd again in her residual left transverse colon. Transverse colectomy was performed, and two advanced cancers and one submucosal invading cancer were detected. Furthermore, two years later, LST type colon cancer was detected in the sigmoid colon by colonscopy. Laparoscopic assisted colectomy was performed and one submucosal invading cancer was detected.

　Eventually, eight colon cancers were generated from the proximal to the disal colon as the patients age increased. Annual or more frequent colonoscopy is recommended in patients with HNPCC.