[Effect of Chemotherapy in Primary Tumor of MSI-H Colon Cancer Aged 50 Years or Younger].

Gan to kagaku ryoho. Cancer & chemotherapy

PubMedID: 24394004

Chika N, Ishibashi K, Kumamoto K, Okada N, Suzuki O, Hatano S, Amano K, Matsuzawa T, Kuwabara K, Sobajima J, Kumagai Y, Baba H, Haga N, Iwama T, Ishida H, Inokuma S, Takeuchi I. [Effect of Chemotherapy in Primary Tumor of MSI-H Colon Cancer Aged 50 Years or Younger]. Gan To Kagaku Ryoho. 2013;40(12):2035-7.
Microsatellite instability( MSI) in colorectal carcinoma is reportedly associated with resistance to 5-fluorouracil-based chemotherapy. Moreover, colorectal cancer patients aged =50 years could potentially have Lynch syndrome. In the present study, we examined 11 colorectal cancer patients with unresectable Stage IV disease who underwent resection of the primary tumor between January 2006 and December 2012. The relationship between the MSI status and the efficacy of first- line oxaliplatin-based chemotherapy was retrospectively examined. The MSI status included MSI-H in 1 patient, MSS-L in 2 patients, and MSS in 8 patients. The MSI-H in 1 patient was associated with familial adenomatous polyposis. Following chemotherapy, among 8 MSS patients, 3 showed stable disease (SD) and 1 showed partial response (PR). Moreover 2 MSH-L patients and 1 MSI-H patient showed progressive disease (PD) after chemotherapy. However, additional data collection is required to determine the effect of oxaliplatin-based chemotherapy for MSS-H or MSS-L colorectal patients aged =59 years.