Spontaneous Regression Of Mismatch Repair-deficient Colon Cancer: A Case Series
Yokota, T., Saito, Y., Takamaru, H., Sekine, S., Nakajima, T., Yamada, M., Sakamoto, T., Taniguchi, H., Kushima, R., Tsukamoto, S., Shida, D., Kanemitsu, Y., & Matsuda, T. (2021). Spontaneous Regression of Mismatch Repair-Deficient Colon Cancer: A Case Series. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association, 19(8), 1720–1722.e3. https://doi.org/10.1016/j.cgh.2020.08.051
View Original Source →Abstract
Spontaneous regression of cancer is a rare phenomenon, with 33 colorectal cancer cases reported between 1900 and 2020.1-4 Spontaneous regression is defined as the partial or complete disappearance of a tumor without treatment.1,3 Several factors may be involved in this process, including biopsy, mechanical stress, humoral factors, and infection.1,5 However, no concrete evidence for the mechanistic insights has been indicated.
Case Details
Disease Location
Cecum
Personal Characteristics
64-year-old woman. History of uterine myoma, colon polyp. Family history of colon and uterine cancer (sister), stomach cancer (brother).
Clinical Characteristics
Presented with bloody stool. A 15 mm tumor was found in the cecum. Biopsy was performed. Histologic findings showed a tubular adenocarcinoma, well differentiated. 85 days later, laparoscopic ileocecal resection with d2 lymphadenectomy was performed
Remission Characteristics
Histologic findings of the resected specimen showed a fibrotic scar with foreign-body giant cells
Treatment & Mechanisms
Proposed Remission Mechanisms
Antitumor immune reaction, which is activated by unidentified triggers, might underlie the tumor regression.
Clinical Treatment
Biopsy