Impact of complementary oral enzyme application on the
postoperative treatment results of breast cancer patients - results of an
epidemiological multicentre retrolective cohort study
Josef Beuth1 • Bernhard Ost • Abolghassem Pakdaman •
Elsbeth Rethfeldt • Paul R. Bock2 • Jürgen Hanisch • Berthold
Schneider3
1Institute for Scientific Evaluation of Naturopathy,
University of Cologne, Koln, Germany
2Ifag Basle,
Switzerland
3Institute of Biometrics, Medical University Hannover,
Germany
Cancer Chemother Pharmacol (2001) 47 (Suppl): 45 – 54
Abstract
Purpose: To evaluate the impact of postoperative treatment with an oral
enzyme (OE) preparation given complementary to an antineoplastic therapy in
patients with breast cancer.
Methods: The design of this
epidemiological study was a retrolective cohort analysis with parallel groups.
Design and conduct of the study were performed to current standards for
prospective, controlled clinical trials. A cohort of 2339 breast cancer patients
undergoing surgical intervention and radio-, chemo- or hormonal therapy were
studied in 216 centres. Of the 2339 patients, 1283 received complementary
treatment with OE and 1056 did not receive OE. Patients with other complementary
medications were excluded and the final analysis was performed with the data
from 649 patients, of whom 239 (37%) were additionally treated with OE (test
group) and 410 (63%) without OE (control group). The median follow-up time for
the test group was 485 days and for the control group 213 days. The primary
endpoint of the study was to determine whether complementary treatment with OE
can reduce typical disease- or therapy-associated signs and symptoms
(gastrointestinal symptoms, mental symptoms, dyspnoea, headache, tumour pain,
cachexia, skin disorders, infections, and side effects associated with the
antineoplastic therapy) in patients with breast cancer. Imbalances for causal
effects (covariates) were adjusted for by means of the propensity score. Outcome
analysis was performed by estimating the linear regression between change in
symptom score and propensity score with all data and using this regression line
to calculate the change in symptom score which would be expected for each
patient. Tumour-associated events (recurrence, metastasis, and death) were
evaluated in terms of the number of events observed and time to event. The
safety of treatment with OE was analysed in terms of the number and severity of
adverse events, their duration, treatment and outcome.
Results: For all symptoms except tumour pain, the adjusted mean improvement
in symptom scores was larger in the test group than in the control group. The
adjusted difference was statistically significant for all symptoms, except tumour
pain and infections. The results show that the typical disease- and therapy-associated
signs and symptoms in patients on complementary therapy with OE during postoperative
treatment were significantly less. For 75% of the test group and 55% of the
control group the physician recorded "no signs and symptoms". A clear reduction
in the side effects of radiotherapy and chemotherapy was documented in 74% of
the test group and 55% of the control group. Analysis of survival, recurrence,
and metastasis demonstrated a reduced number of events in the test group. There
was evidence of a beneficial influence of OE on time to event, although the
median observation time was too short in these breast cancer patients to draw
definite conclusions. The safety component was judged in 98% of the test group
and 76% of the control group as "very good" or "good". In the total sample of
2339 patients, the rate of OE-associatedadverse reactions was
3.2%. All side effects were mild to moderate gastrointestinal symptoms.
Conclusion: Complementary
treatment of breast cancer patients with OE improves the quality of life by
reducing signs and symptoms of the disease and the side effects of adjuvant
antineoplastic therapies. This epidemiological retrolective cohort analysis
provides evidence that the patients may also gain benefit by a prolongation of
the time to event for cancer recurrence, metastasis and survival. OE was
generally well tolerated.
Key words Retrolective cohort study •
Complementary treatment • Breast cancer • Oral enzyme preparation • Symptoms •
Events