Fatty acid breath test values in the malabsorption range in cancer patients

Fatty acid absorption breath tests (FABT) were found to be abnormal in most subjects in a group of cancer patients selected to exclude common causes of abnormal lipid absorption, including chemotherapy and radiation therapy. The breath tests were abnormal in both quality (delayed peak in 9 of 10 patients) and quantity (reduced maximum peak in 5 of 10 patients) of fatty acid absorption. Retrospective separation of patients into 2 groups (normal or low maximum peak height FABT), either at a common time after the start of the test or at each individual's maximum peak height FABT regardless of time, was significant at 0.005 and 0.001, respectively. The low maximum peak heights were in the range of the malabsorption syndrome. Further studies of pancreatic function and fat malabsorption are warranted before the abnormal results can be ascribed to altered intermediary metabolism or peripheral utilization of lipids.