Isolated diaphragmatic metastasis originated from adenocarcinoma of the colon

Isolated diaphragmatic metastasis arising from colorectal cancer has been reported only one case in the literature presently. Here, we presented a new case and discussed the possible pathogenesis and the treatment options. A 42-year-old male patient had received anterior resection for sigmoid colon cancer. Although the increased serum CEA level was detected 20 months after the surgery, metastatic lesion could not be detected by repeated colonoscopy, CT scan, bone scan or PET scan for 35 months. We could detect a suspicious metastatic lesion on the liver by CT scan at 56 month after the surgery. During a second-look operation, we found a solitary metastasis on the diaphragm and removed it along with the 1 cm tumor-free resection margin. Although the prognosis associated with skeletal metastasis is poor, the complete resection of isolated diaphragmatic metastasis and subsequent appropriate adjuvant chemotherapy may achieve a cure the disease provided that other metastatic lesions are absent.