CAJ | 학술논문

目的：探讨原发性肛管-直肠恶性黑色素瘤（AMM）的 CT 和 MRI 表现。方法：回顾性分析本院经病理证实的15例 AMM 患者的临床、CT、MRI 和病理资料。11例行 CT 检查，3例行 MRI 检查，1例行 CT 和 MRI 检查。结果：15例 AMM 中，10例病变位于直肠远端与肛管交界处，2例位于直肠，3例位于肛管。肿瘤形态呈蕈伞形肿块9例，肠壁环形增厚4例，肠壁未见明显增厚2例。4例有肺部或者肝脏转移，5例有周围淋巴结转移。15例患者均未见明星的肠梗阻征象。CT 平扫示肿块呈稍低密度，最大径约2～4cm，增强后强化方式不一，以中度强化为主。MRI 示肿瘤在 T1 WI 上以等信号为主，T2 WI 上以稍高信号为主，DWI 上呈高信号，增强后均有明显强化。结论：AMM 的 CT 和 MRI 表现具有一定特征性；但 AMM 病灶较大时，MRI 信号不具有黑色素瘤特异性的典型信号。CT 检查有助于发现远处转移灶，MRI 检查对其鉴别诊断有提示价值。
목적：탐토원발성항관-직장악성흑색소류（AMM）적 CT 화 MRI 표현。방법：회고성분석본원경병리증실적15례 AMM 환자적림상、CT、MRI 화병리자료。11례행 CT 검사，3례행 MRI 검사，1례행 CT 화 MRI 검사。결과：15례 AMM 중，10례병변위우직장원단여항관교계처，2례위우직장，3례위우항관。종류형태정심산형종괴9례，장벽배형증후4례，장벽미견명현증후2례。4례유폐부혹자간장전이，5례유주위림파결전이。15례환자균미견명성적장경조정상。CT 평소시종괴정초저밀도，최대경약2～4cm，증강후강화방식불일，이중도강화위주。MRI 시종류재 T1 WI 상이등신호위주，T2 WI 상이초고신호위주，DWI 상정고신호，증강후균유명현강화。결론：AMM 적 CT 화 MRI 표현구유일정특정성；단 AMM 병조교대시，MRI 신호불구유흑색소류특이성적전형신호。CT 검사유조우발현원처전이조，MRI 검사대기감별진단유제시개치。
Objective:To analyze the CT and MRI findings of primary anorectal malignant melanoma (AMM).Methods:The clinical,CT and MRI materials of 15 cases with AMM confirmed by surgery and pathology were analyzed retrospective-ly.Of them,11 patients had CT scanning,3 had MR imaging and 1 had both CT and MRI performed.Results:Of the 15 pa-tients with AMM,tumor located at the junction of distal rectum and anal canal (10 cases),rectum (2 cases)and anal canal (3 cases).Tumors usually appeared as intraluminal fungiform masses (n=9),circumscribed thickening of bowel wall (n=4)and with no bowel wall thickening (n=2).Pulmonary or hepatic metastasis could be assessed in four patients.Five pa-tients had perirectal lymph node metastasis.There was no evidence of bowel obstruction in any of the patients.Tumor on non-enhanced CT appeared hypo-attenuation,the maximum diameter ranged from 2cm to 4cm.The enhanced pattern of tumor varied,most of them showed moderate enhancement.On MRI,tumors mainly appeared iso-intense on T1 WI,slightly hyper-intense on T2 WI,hyper-intense on DWI,and showed markedly heterogeneous enhancement on contrast enhanced T1 WI.Conclusion:Some CT and MRI characteristics of AMM could be revealed.However,no typical MRI features could be assessed in large lesion.CT scanning was helpful to identify distant metastases and MRI was valuable in differential diagnosis.