Is there a link between KRAS mutations and the risk of colorectal cancer spreading to the lungs?

This study investigated whether mutations (permanent change) in the KRAS gene can predict the development of lung metastases (spread of cancer to the lungs from the rectum or colon) in advanced colorectal cancer.

Colorectal tumors can have genetic mutations. One of the most common mutations is of the KRAS gene-an important protein involved in cell signaling. KRAS mutations have been associated with lung metastases at diagnosis of metastatic colorectal cancer. However, it is not known whether KRAS mutations can help predict which patients are at risk of developing lung metastasis.

This study examined the medical records of 494 patients with colorectal cancer that had spread to the lungs. Each patient had been genetically tested for KRAS mutations. The authors examined whether KRAS mutations were linked with how long it took for the cancer to spread to the lungs (time-to-lung metastasis) or overall survival time.

Of the 494 patients, 202 (41%) had tumors with KRAS mutations. The odds of having lung metastases at the time of colorectal cancer diagnosis were 90% higher for patients with KRAS mutations.

Patients with KRAS mutations had a shorter time-to-lung metastasis (15.2 months) compared to patients without KRAS mutations (22.4 months). Despite this, there was no difference in overall survival time between patients with and without the KRAS mutations.

The authors concluded that testing for KRAS mutations could help identify patients who are at risk of developing lung metastases in colorectal cancer.