内容紹介
Summary
An 87-year-old woman was referred owing to lightheadedness. Severe anemia(Hb 3.9 g/dL)was detected, and colonoscopy revealed a circumferential elevated lesion at the transverse colon(Group 5, por). The patient was diagnosed with colon cancer(cT4a, N0, M0, StageⅡ), and right hemicolectomy was performed. Immunochemical analysis showed that the lesion was MLH1- and PMS2- and confirmed a diagnosis of medullary carcinoma. Although the patient was discharged 48 days after surgery without any incident, she was readmitted because of lower leg edema. Liver metastasis and peritoneal dissemination were suspected on performing computed tomography, and the patient died 35 days after readmission. Medullary carcinoma has molecular pathological features such as methylation of the promoter region and associated attenuation of MLH1 protein expression, as well as microsatellite instability. The prognosis for medullary carcinoma is relatively good compared to that for poorly differentiated adenocarcinoma, though the present case had a poor prognosis. Herein, we report a literature review.
要旨
症例は87歳,女性。ふらつきを主訴に受診され,高度貧血(Hb 3.9 g/dL)を指摘された。大腸内視鏡検査で横行結腸肝弯局部結腸に全周性の隆起性病変を認め,生検結果はGroup 5(por)であった。全身精査の結果,cT4a,N0,M0,StageⅡの診断となり,右半結腸切除術を施行した。切除標本の免疫染色の結果,MLH1とPMS2が陰性であり,髄様癌の診断となった。術後経過は良好であり,術後48日目に退院となった。退院後31日目,下腿浮腫の精査目的に再入院となり,CT検査で肝転移・腹膜播種再発が疑われ,再入院後35日目に死亡した。髄様癌はMLH1遺伝子のプロモーター領域のメチル化とそれに伴うMLH1蛋白発現の減弱,マイクロサテライト不安定性といった分子病理学的特徴を有する。低分化腺癌と比べて比較的予後良好とされるが,本症例では非常に急速な転帰をたどった。若干の文献的考察を加えて報告する。
目次
An 87-year-old woman was referred owing to lightheadedness. Severe anemia(Hb 3.9 g/dL)was detected, and colonoscopy revealed a circumferential elevated lesion at the transverse colon(Group 5, por). The patient was diagnosed with colon cancer(cT4a, N0, M0, StageⅡ), and right hemicolectomy was performed. Immunochemical analysis showed that the lesion was MLH1- and PMS2- and confirmed a diagnosis of medullary carcinoma. Although the patient was discharged 48 days after surgery without any incident, she was readmitted because of lower leg edema. Liver metastasis and peritoneal dissemination were suspected on performing computed tomography, and the patient died 35 days after readmission. Medullary carcinoma has molecular pathological features such as methylation of the promoter region and associated attenuation of MLH1 protein expression, as well as microsatellite instability. The prognosis for medullary carcinoma is relatively good compared to that for poorly differentiated adenocarcinoma, though the present case had a poor prognosis. Herein, we report a literature review.
要旨
症例は87歳,女性。ふらつきを主訴に受診され,高度貧血(Hb 3.9 g/dL)を指摘された。大腸内視鏡検査で横行結腸肝弯局部結腸に全周性の隆起性病変を認め,生検結果はGroup 5(por)であった。全身精査の結果,cT4a,N0,M0,StageⅡの診断となり,右半結腸切除術を施行した。切除標本の免疫染色の結果,MLH1とPMS2が陰性であり,髄様癌の診断となった。術後経過は良好であり,術後48日目に退院となった。退院後31日目,下腿浮腫の精査目的に再入院となり,CT検査で肝転移・腹膜播種再発が疑われ,再入院後35日目に死亡した。髄様癌はMLH1遺伝子のプロモーター領域のメチル化とそれに伴うMLH1蛋白発現の減弱,マイクロサテライト不安定性といった分子病理学的特徴を有する。低分化腺癌と比べて比較的予後良好とされるが,本症例では非常に急速な転帰をたどった。若干の文献的考察を加えて報告する。