Invasive colon cancer derived from a small superficial depressed cancer - Report of a case

A 64-year-old male in May 1997 was diagnosed by colonoscopy and a barium en ema examination as having an invasive cancer in the transverse colon. Patho logic study of the resected surgical specimen revealed a well-differentiate d adenocarcinoma invading the muscularis propria. He had a colonoscopic exa mination in 1991 and was diagnosed as having multiple adenomas, which were endoscopically removed. After that he had annual colonoscopy or barium enem a examination follow-ups. At endoscopy in February 1994, a superficial depr essed cancer 6 mm in diameter had been detected. However, the cancer was no t seen again in several endoscopic examinations until one in 1997. Because the location of the lesion detected in 1994 and that of the invasive carcin oma detected in 1997 were identical, it was considered that the superficial depressed cancer developed, 40 months later, to an advanced cancer. Doubli ng time was calculated as 8.4 months.