Yasunori Ishido

Analysis of the Relationship between Sex and Chromosomal Aberrations in Colorectal Cancer by Comparative Genomic Hybridization

Colorectal cancer is thought to be more common in men than in women. The chromosomal locations of DNA gains and losses in surgical specimens of colorectal tumours were detected by comparative genomic hybridization and were compared by gender. Five chromosomal regions, 7p, 8p, 8q, Xp and Xq, contained multiple gains that were significantly more common in males than in females, and within these regions, the differences were significant for Xp21, Xp11.3, Xp11.4 and Xq26. Regions 1p, 3q, 11q, 12p, 12q and 15q contained multiple sites of gain that were significantly more common in females than in males. Tumours from male and female patients showed significantly more losses at 11p and 15q, and at 4q and Xq, respectively. The fact that gains in X-chromosomal regions were detected with a significantly higher frequency in tumours from male patients suggests that the difference between the genders might be explained by X-chromosomal inactivation.

Genomic copy-number aberrations related to lymph-node metastasis of colon cancer.

Lymph-node metastasis is an important indicator in the diagnosis of colon cancer. In order to determine the genes involved in metastasis, genomic copy-number aberrations in the primary tumours and lymph-node metastases were analysed in 12 patients using comparative genomic hybridization. This method detects genomic copy-number changes at the chromosomal level and the identification of the regions of aberration on any chromosome. Copy-number gains at 6p12 and losses at 8p12 were observed in a greater number of the primary tumours than in the metastases. These aberrations appear to be involved in lymph-node metastasis of colon cancer, and may allow measurement of the risk of lymph-node metastasis from a given colon cancer.

A Case of Benign Bile Duct Stenosis caused by a Clip Two Years after Laparoscopic Cholecystectomy

腹腔鏡下胆嚢摘出術 (laparoscopic cholecystectomy; 以下, LC) 後のクリップによる良性胆管狭窄は比較的まれである. 今回, LCの2年後に良性胆管狭窄を来した1例を経験した. 症例は68歳の男性で, 平成17年5月に胆石症でLCを施行. 平成19年5月に褐色尿と体重減少で受診. 黄疸と肝機能障害があり入院. 腹部CTと磁気共鳴膵胆管撮影検査で中部胆管狭窄が認められた. 直接胆管造影検査ではLC時のクリップ近傍で狭窄が認められた. 腫瘍マーカーに上昇はなく, 胆汁細胞診はclass I.以上より, 胆管癌を疑い平成19年6月手術を施行. 狭窄部を含む胆管を切除. 病理組織学的検査ではinflammatory changeであり, 胆管を圧排していた壁外組織中にLC 時のクリップが認められた. 金属クリップの合併症は増加傾向にあり, 今後は吸収性物質を使用するなど, 金属クリップを使わない工夫が重要と思われる.

Early colon cancer detected by 18F-FDG PET

Positron emission tomography (PET) is a noninvasive functional imaging modality that can disclose the presence of a malignant disease. It has recently been reported that PET may be useful to detect primary colorectal cancer (CRC). We present the case of a 47-yr-old man with early colon cancer detected by 18F-fluorodeoxyglucose (FDG) PET. The patient consulted us because of a positive fecal occult blood test and focal FDG uptake in the pelvic cavity detected at a physical check-up. After the usual work up, he was diagnosed as having a sigmoid polyp, 16 mm in diameter. Subsequently, colonoscopic polypectomy was carried out. The surgical specimen was histologically diagnosed as a well-differentiated adenocarcinoma, invading the submucosal layer with lymphatic invasion. Therefore, the involved portion of the sigmoid colon was laparoscopically resected. The FDG PET carried out 1 yr after the operation, showed no abnormal FDG uptake. PET can noninvasively detect an early colon cancer as small as in our patient, as well as other cancers in the whole body. Therefore, we consider it suitable as a screening examination.