KRAS mutation is associated with which carcinoma?

• A. Colon adenocarcinoma
• B. Ovarian carcinomas
• C. Endometrial carcinomas
• D. Cervical carcinomas

Answer: (A)

KRAS mutations activate the Ras-MAPK signaling pathway and are a hallmark event in colorectal cancer progression. In colon adenocarcinoma, activating KRAS mutations occur in a substantial fraction of tumors and typically arise during the adenoma-to-carcinoma sequence after the initial APC alteration. This mutation status also has practical treatment implications, as KRAS-mutant tumors generally do not respond to anti-EGFR therapies like cetuximab or panitumumab. While KRAS alterations can be seen in other cancers, they are most characteristically associated with colon adenocarcinoma among the options given, making it the best answer.