[A Case of Advanced Transverse Colon Cancer with Relapse behind the Rectum after Laparoscopic-Assisted Resection].

A 60's male patient underwent laparoscopic left hemicolectomy with D3 lymph node dissection for transverse colon cancer. Adjuvant chemotherapy with tegafur-uracil and leucovorin was administered.Thirty -four months later, MRI scan revealed a mass with sacrum invasion.Radiation therapy(39 Gy/13 Fr)was performed followed by chemotherapy(modified oxaliplatin, leucovorin, and 5-fluorouracil plus bevacizumab).Two weeks after the completion of radiation therapy, staging laparoscopy and tissue biopsy was performed in the hard tumor, which was located at the caudal end of the incisional scar of the retroperitoneum, in front of the sacrum.The pathological diagnosis revealed metastasis from transverse colon cancer.Radiographic examination showed partial response to radiochemotherapy, and buttock pain decreased.CT review before pain developed showed a small tumor located mainly in the mesorectum slightly adjacent to the sacrum, suggesting the implantation of cancer cells to the stripped plane behind the mesorectum during the surgery.