Among cancer patients being treated surgically for stage 1-111 non-metastatic colorectal carcinoma, those who received supportive care with the fermented mistletoe extract Iscador (ISC) (from Viscum album L.) along with conventional adjuvant (given after surgery) chemo- and/or radiotherapy had fewer adverse drug reactions (ADRs) as compared with those who received similar treatment with only passive aftercare. "Stage 1-111" implies a range from very early stages to those in which the tumor has spread to nearby lymph nodes. The observational study was based on medical records from 804 consecutive patients (429 ISC, 375 controls) treated at 26 centers in Germany and Switzerland. The lead investigator was W.E. Friedel, MD, Hospital Bad Bocklet, Bad Bocklet, Germany.

Patients received subcutaneous ISC injections two or three times per week as part of long-term supportive care. Investigators compared ADRs related to conventional suppor­tive care or to care with ISC added, duration of hospitalization, and disease-free survival (DFS). In their analysis, they adjusted for any differences in patients' baseline characteristics that could affect outcomes.

After treatment of about two months and at a mean follow-up of 55 months, ADRs were reported in 19.1% of patients receiving ISC and in 48.3% of patients receiving passive supportive care. The difference was highly significant statistically. Side effects related to the gastrointestinal system and to the central nervous system, especially, were reduced among those receiving ISC. Karnofsky Index, a measure of a patient's general status, which was actually lower (worse) at baseline in the ISC group, improved continuously in the ISC group and was still at baseline level in the control group at the end of therapy. Hospital stays were significantly shorter (mean 35.5 days ISC, versus 41.2 days in controls) and the hazard ratio (risk of experiencing a tumor-related event such as tumor recurrence, distant metastasis or death) was a significant 32% lower for the ISC group.

Systemic reactions caused interruption of therapy in 1.2% of cases and 23.3% of ISC patients had mild to moderate injection site reactions. No life-threatening or persisting ADRs were attributed to ISC, however, nor were any tumor increases reported with ISC.

Dr. Friedel concluded that in this largest-to-date systematic comparative clinical data evaluation concerning supportive mistletoe treatment in colorectal cancer, in the ISC group there were significantly fewer ADRs from chemotherapy/ radiotherapy, fewer disease- and therapy-related symptoms, and longer disease-free survival. "Based on these data," he said, "a prospective randomized clinical trial to confirm these results is warranted."