Ascending colon cancer coincident with mesenteric phlebosclerosis associated with the long-term oral intake of Chinese herb containing gardenia fruit: A case report and literature review.

Mesenteric phlebosclerosis is a recently discovered rare ischemic colon disease. The relationship between mesenteric phlebosclerosis and the use of herbal medicine containing gardenia fruit was recently reported. Although the relationship between colon cancer and mesenteric phlebosclerosis has not been described, some cases of colorectal cancer coincident with mesenteric phlebosclerosis have been reported. We treated a 63-year-old female who was diagnosed with ascending colon cancer coincident with mesenteric phlebosclerosis. She had been taking a Chinese herb containing gardenia fruit for over 18 years. The ascending colon cancer was clinically diagnosed as T2, N0, and M0 according to Japanese classification of colorectal carcinoma and the mesenteric phlebosclerosis had spread from the cecum to the descending colon. She underwent laparoscopic subtotal colectomy with en bloc removal of the regional lymph nodes, and both the ascending colon cancer and mesenteric phlebosclerosis were completely resected. The microscopic findings show that the tumor was well-differentiated tubular adenocarcinoma invading the muscular propria with no regional lymph node metastasis, and the mesenteric phlebosclerosis lesion was characterized by marked fibrous thickening of the venous walls with calcification, marked transmural fibrosis and deposition of the collagen in the mucosa, accompanied by macrophages within the vessel walls. In literature review, 10 cases with colorectal cancer coincident with mesenteric phlebosclerosis were reported. 9 of 10 cases (90%) had cancer in the right-side colon affected by mesenteric phlebosclerosis, and 5 of 10 cases (50%) were associated with the use of a Chinese herb containing gardenia fruit. It was recently demonstrated that genipin, which is a metabolite bio-transformed from gardenia fruit, possesses carcinogenesis. We speculate that genipin may be associated with not only the development of mesenteric phlebosclerosis but also carcinogenesis in the right-side colon. In conclusion, our findings suggest that the safety of gardenia fruit should be re-evaluated, and gastroenterologists should be aware that gardenia fruit may be risk factor for not only the development of mesenteric phlebosclerosis but also carcinogenesis in the proximal colon.