Higher Intakes of EPA/DHA Omega-3 Fatty Acids and Extended Survival Following Colon Cancer
Reference:
Van Blarigan , E. L. et al., Cancer Epidemiology, Biomarkers and Prevention, in press, 2018
Dept. of Epidemiology and Biostatistics, Univ. of California, San Francisco, Calif., USA
Summary:
This study followed 1,011 colon cancer patients of mixed genders and average age of 60 years (resected for stage III adenocarcinoma of the colon with no metastases) for a median period of 7 years. A food frequency questionnaire (FFQ) was used to estimate the amounts and types of various fish/seafood produce as consumed. Marine-based omega-3 fatty acid intakes (predominantly as EPA plus DHA) were assessed by nutrient compositional data of various fish/seafood from the USDA and a knowledge of omega-3 fatty acid intakes from fish oil supplementation. The primary outcome was disease-free survival – defined as time from the baseline FFQ to tumor recurrence, occurrence of a new primary colon tumor, or death from any cause, whichever came first. Recurrence-free survival was defined as time from the baseline FFQ to tumor recurrence or occurrence of a new primary colon tumor.
The results indicated that higher intakes of marine omega-3 fatty acids after the diagnosis of colon cancer were associated with longer disease-free survivals. Specifically, those patients in the top 25 % with respect to marine omega-3 intakes (median intakes of 400 mgs/day) had an event rate on follow-up of only 33.6 % as compared to 44.4 % for those in the bottom 25 % with respect to intakes (median intakes of only 90 mgs/day). Similar benefits on recurrence-free survival were also seen with the higher intakes. Individuals consuming dark meat fish at least once or more per week also exhibited better disease-free survivals as compared to those not consuming such fish.
It is noted that this group previously reported that higher intakes of marine omega-3 fatty acids after the diagnosis of colorectal cancer (CRC) were associated with a lower risk of CRC-specific mortality (Song, M. et al., Gut, 66: 1790-1796 (2017)). Patients who consumed at least 300 mgs of such omega-3 fatty acids/day had a 41 % lower risk of CRC-specific mortality as compared to patients who consumed less than 100 mgs/day. It is noted that adult intakes in North America of EPA (eicosapentaenoic acid) plus DHA (docosahexaenoic acid) currently average 110-130 mgs/person/day which is well below the minimum targets of at least 300-400 mgs/person/day mentioned above which appear to enhance outcomes in those found to have CRC. Public health programs and patient education in the gastroenterology-cancer field should be instituted which offer nutritional advice for those with CRC including higher intakes of EPA/DHA to better manage their disease and to retard its progression.