Aspirin Reduces Recurrences in Colorectal Cancer Among Patients With a PIK3CA Mutation

The regular use of low-dose aspirin appears to reduce the risk of a cancer recurrence among patients with colorectal cancer who have the PIK3CA mutation. These results were recently published in the Journal of Clinical Oncology.

Colorectal cancer is the second leading cause of cancer-related deaths among men and women in the United States. If detected and treated early, cure rates remain high for this disease. However, once the cancer has spread from its site of origin to distant sites in the body, cure rates fall dramatically.

Clinical studies have indicated a potential association between the use of non-steroidal anti-inflammatories and/or aspirin and a reduced risk of recurrences in colorectal cancer. However, prior data has implicated that only patients with a PIK3CA mutation gain this benefit from aspirin. To further explore this possible relationship, researchers conducted another study evaluating patients with colorectal cancer with or without the PIK3CA mutation.

The study included data from 896 participants involved in the VICTOR trial (Vioxx in Colorectal Cancer Therapy: Definition of Optimal Regimen trial). Researchers performed molecular analysis on the tissue samples of cancer, including PIK3CA mutation status. Following therapy for colorectal cancer, patients in the VICTOR trial were divided into groups. One group received the non-steroidal anti-inflammatory Vioxx (rofecoxib), one group received placebo, and one group received low-dose aspirin.

Patients treated with Vioxx demonstrated no differences in recurrence rates, regardless of PIK3CA mutation status, compared to placebo.
In contrast, the use of low-dose aspiring significantly reduced rates of recurrences among patients with the PIK3CA mutation compared to placebo. However, patients without the PIK3CA mutation did not benefit from the use of aspirin.
The researchers concluded that the use of low-dose aspirin appears to significantly reduce the rates of cancer recurrences among patients with colorectal cancer and a PIK3CA mutation. The authors stated that the PIK3CA mutation merits further evaluation as a predictive biomarker for aspirin therapy. Our findings are concordant with recent data and support the prospective investigation of adjuvant aspirin in PIK3CA-mutant [colorectal cancer].”

Reference: Domingo E, Church D, Sieber O, et al. Evaluation of PIK3CA mutation as a predictor of benefit of nonsteroidal anti-inflammatory drug therapy in colorectal cancer. Journal of Clinical Oncology. 2013;31(34):4297-4305.