Clinical outcomes for cancer patients using complementary and alternative medicine

Over half of cancer patients in Singapore use some form of complementary or alternative medicine (CAM) to improve their immunity and general health status. The effectiveness of CAM, however, in reducing acute complications is currently unknown. Concerns also exist as to whether CAM may cause toxic effects in patients with cancer.

To investigate the changes in general health status, immunity, and organ function over a 6-month period in CAM and non-CAM users with cancer.

The authors designed a single-center, retrospective cohort study. The patients had participated previously in a cross-sectional prevalence survey about the types of oral CAM they were using in addition to chemotherapy. The authors used the data from the survey and clinical and medication-use information from patients' medical and pharmaceutical records to complete the current study.

The study occurred at the National Cancer Centre Singapore (NCCS), which is the largest ambulatory cancer center in Singapore and treats two-thirds of the solid-tumor patients in Singapore. The study excluded patients if their medical records were incomplete and/or if the patients had not received any cytotoxic or targeted therapies at the time of survey.

The authors reviewed the records of a total of 403 patients and excluded 46 patients because their records were missing (n=20) or because they had not received any form of anticancer treatment at the time of survey (n=26). They included 357 patients in the current study. The authors did not contact patients for this follow-up study.

The authors collected data on clinical characteristics for each patient and assessed the differences between each characteristic at baseline (at the time of the survey) and at 6 months after baseline measurement. The authors evaluated clinical characteristics using the National Cancer Institute's Common Terminology Criteria for Adverse Events version 3.

As a whole, CAM use provided an absolute reduction of infection episodes by 11.9% (P=.045) and of antibiotic use by 10.3% (P=.022). Subgroup analysis showed a reduction of documented infection by 17.9% (P=.02) and a 13% decrease in hospitalizations due to infections (P=.043) among metastatic cancer patients who used CAM. CAM usage was not associated with significant changes of hepatic and renal function.

CAM use in patients with cancer was associated with a reduction in hospitalizations and requirements for antibiotics. CAM use was not associated with significant changes in hepatic and renal function. There is a need for well-designed, prospective clinical studies to confirm these findings.