大约有1/3的直肠腺癌患者远处转移是其首发症状,最常见的部位是肝(83%),其次是肺(15%)和骨(5.9%)。本文报告两例少见的转移部位,一例为下颌第三磨牙的冠周,另一例为拔牙创的龈组织。例一,女性,45岁。1980年因直肠癌手术,镜检为中等分化腺癌。肿瘤已穿过肌层累及周围组织,附近找到7个淋巴结均见有转移癌以及静脉有癌组织浸润。术后4个月,因小肠梗阻伴腹膜炎而行第二次剖腹探查,盆腔和肝均未见肿瘤。再过5个月,发现会阴结节并伴右臀和大腿后份疼痛,C T扫描显示右盆腔有一大肿块并累及髂骨。与此同时, Approximately one-third of patients with rectal adenocarcinoma are at the onset of distant metastases, the most common site being liver (83%), followed by lung (15%) and bone (5.9%). This article reports two rare cases of metastatic sites, one for the mandibular third molar crown and the other for the extraction of dental caries. Example 1, female, 45 years old. In 1980 for rectal cancer surgery, microscopic examination was moderately differentiated adenocarcinoma. Tumors have passed through the muscles and involve the surrounding tissue. Seven metastases were found in the vicinity. Metastatic cancers were found in both lymph nodes and cancerous tissues invaded the veins. Four months after the operation, a second exploratory laparotomy was performed due to small bowel obstruction with peritonitis. No tumors were found in the pelvis and liver. After another 5 months, a perineal nodule was found with pain in the right hip and thighs. CT scan revealed a large mass in the right pelvic cavity and involved the patella. at the same time,