Comparison of 5-fluorouracil alone, 5-fluorouracil with levamisole, and 5-fluorouracil with hepatic irradiation in the treatment of patients with residual, nonmeasurable, intra-abdominal metastasis after undergoing resection for colorectal carcinoma.

BACKGROUND

The authors conducted a randomized Phase III trial of three treatment regimens for patients with residual, nonmeasurable, intra-abdominal metastatic disease after undergoing resection for primary colorectal carcinoma.

METHODS

To be eligible for this study, patients had to be both free of other malignancies and capable of starting their therapy within 3-6 weeks after surgery. They were required to have an Eastern Cooperative Oncology Group performance status < 3; to be chemotherapy, radiation, and immunotherapy naïve; to have adequate bone marrow, renal, and hepatic function; and to provide written, informed consent. The patients were divided into two cohorts: patients with no demonstrable hepatic metastasis (Group A) and patients with hepatic metastasis (Group B).

RESULTS

The 229 patients in Group A were randomized to receive either 5-fluorouracil (5-FU) (n = 116 patients) or 5-FU with levamisole (n = 113 patients). The median survival (15.4 months and 15.3 months, respectively, for Groups A and B) was virtually identical. The two groups also were similar in terms of time to treatment progression, which was 7.9 months for group that received 5-FU alone 7.7 months for the group that received levamisole with 5-FU. The 168 patients in Group B with hepatic metastasis underwent a three-way randomization: 5-FU alone (n = 60 patients), 5-FU with levamisole (n = 54 patients), and 5-FU with hepatic irradiation (n = 54 patients). The median overall survival for the three treatment arms were similar, with 17.3 months for the group that received 5-FU alone, 16 months for the group that received 5-FU with levamisole, and 14.4 months for the group that received hepatic irradiation in addition to 5-FU: The time to treatment failure was 6.7 months, 6.8 months, and 8.3 months, respectively, for the three groups. The toxicity experienced by patients was as expected with the regimens, and no differences were observed between any of the treatment groups. The primary toxicities were hematologic and gastrointestinal. There was one treatment-related death due to adult respiratory distress syndrome, which occurred on the first day of the fourth cycle of 5-FU and levamisole. Other Grade 4 toxicities included nine patients with Grade 4 leukopenia, one patient with Grade 4 sepsis, and one patient with Grade 4 gastrointestinal toxicity, including blood loss and diarrhea.

CONCLUSIONS

This study showed no treatment advantage for any of the combined modalities over 5-FU alone in this group of patients with intra-abdominal, nonmeasurable disease.