A phase I study14 of 22 patients with incurable
neoplastic disease found a maximum-tolerated dose of 0.3 g of
fish oil per day (the composition of the fish oil was different than
that in this study), with gastrointestinal dose-limiting toxicities
(oily diarrhea, “unable to tolerate in esophagus or stomach”). In
a dose-escalation study13 of 18 patients with unresectable pancreatic
cancer, a median maximum dose of 12 g of fish oil per
day (same capsule composition as this study) was tolerated.
Therefore, long-term compliance with fish oil preparations is
difficult. Because, in our study, placebo capsules were not well
tolerated either, the consumption of high doses of oily capsules
might be inherently problematic. At present, it is not known
whether the tolerability of oral supplementation with n-3 fatty
acids can be improved by using preparations containing EPA
instead of fish oil. In one study, 26 patients with unresectable
pancreatic cancer and a median weight loss per month of 2 kg
tolerated doses of 6 g/d of high-purity (95%) EPA over several
months.16 A new high-purity preparation of EPA as a 20% oil
and water diester emulsion was studied in a phase I study of
five cancer patients