Among patients with stage III colon cancer, postdiagnostic consumption of unprocessed red meat or processed meat is not associated with the risk for recurrence or mortality, according to study results published in JAMA Network Open.
Researchers prospectively examined unprocessed red meat and processed meat intake among patients with stage III colon cancer from the Cancer and Leukemia Group B adjuvant chemotherapy trial from 1999 to 2001. The participants completed a survey about 3 months after diagnosis and a second survey about 6 months after treatment. The surveys included a validated food frequency questionnaire.
The primary endpoint was the combination of documented disease recurrence, a new primary colon tumor, or death from any cause.
A total of 1011 patients with stage III colon cancer were included. Their median age at enrollment was 60 (IQR, 51-69) years, 44% were women, and 89% were White. Among the cohort, 305 total deaths and 81 events of recurrence without death occurred during a median follow-up of 6.6 (IQR, 1.9-7.5) years.
The final multivariable analysis model showed that participants in the fourth quartile (median, 6.9 servings/week) of unprocessed red meat intake had a lower incidence rate for cancer recurrence or death compared with participants in the first quartile (median 1.5 servings/week), although the difference was not statistically significant (hazard ratio [HR], 0.84; 95% CI, 0.58-1.23; P for trend =.33). The HR for overall mortality for participants in the fourth quartile of unprocessed red meat intake vs those in the first quartile was 0.71, although it was not statistically significant (95% CI, 0.47-1.07; P for trend =.11).
No significant associations were found between processed meat intake and colon cancer recurrence or survival. The HR for a comparison of the risk for cancer recurrence or death in participants in the fourth quartile (median, 5.2 servings/week) vs first quartile (median, 0.7 servings/week) of processed meat was 1.05 (95% CI, 0.75-1.47) in the fully adjusted model. The values were similar for overall mortality (HR, 1.04; 95% CI, 0.72-1.51).
The researchers noted that their observational study was based on self-reported dietary behavior, and so they could not rule out the potential for unmeasured or residual confounding. Also, the study only included patients with stage III colon cancer, and, therefore, the results may not be applicable to patients with stages I to II or IV. In addition, the study population was not racially and ethnically diverse.
The results are “an important contribution to the literature on postdiagnostic health behaviors and outcomes among cancer survivors,” the investigators wrote. “Although our study has limitations, these findings can potentially inform patient counseling and the development of dietary guidelines specific for cancer survivors.”
Van Blarigan EL, Ou F-S, Bainter TM, et al. Associations between unprocessed red meat and processed meat with risk of recurrence and mortality in patients with stage III colon cancer. JAMA Netw Open. Published online February 22, 2022. doi:10.1001/jamanetworkopen.2022.0145