Comparison of the chemosensitivity of the primary lesion and a pancreatic metastasis of colon cancer: a case report.

Pancreatic metastasis from colorectal cancer is rare, and accounts for less than 2% of all pancreatic metastases. There have been no studies that have reported the differences in the sensitivity to chemotherapy between the primary lesion and the pancreatic metastasis in colorectal cancer. We experienced a rare example of pancreatic metastasis from colorectal cancer, and report here the difference in the sensitivity to the antitumor drug. A 68-year-old female underwent colectomy for rectal carcinoma with a mass in the pancreatic tail and the liver. The patient also underwent a distal pancreatectomy and a segmental liver resection at the same time. v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) and tumor protein 53 (TP53) gene mutation analyses, in addition to the histopathological examinations, revealed tumors of the liver and the pancreatic tail as being metastases from the primary carcinoma. We employed a collagen gel droplet-embedded culture drug sensitivity test for both the primary lesion and the pancreatic metastasis. The sensitivity to oxaliplatin and FOLFOX (5-flurouracil, folinic acid and oxaliplatin) were lower in the pancreatic metastasis compared to the primary lesion. In conclusion, pancreatic metastasis from colorectal malignancy is rare, and the present results suggest that there are potential differences in the sensitivity to chemotherapy between the primary colorectal tumor and its pancreatic metastasis.