A cost-utility approach to the use of 5-fluorouracil and levamisole as adjuvant chemotherapy for Dukes' C colonic carcinoma.

OBJECTIVE

To perform an economic evaluation of the joint use of 5-fluorouracil and levamisole as adjuvant chemotherapy in patients with fully resected Dukes' Stage C carcinoma of the colon, compared with resection and no chemotherapy. The evaluation was prompted by a study (N Engl J Med 1990; 322: 352-358) which recommended a new treatment standard for colon cancer: a 52-week course of fluorouracil, with levamisole every second week, as adjuvant chemotherapy. This recommendation raised several concerns, particularly about the quality of life of patients undergoing such a long course of chemotherapy and the costs to the health care system.

METHODS

The cost of the surgery plus chemotherapy was estimated and compared with the cost of surgery alone. Descriptions of quality of life were developed from interviews with patients and health professionals, and the time trade off technique was then used to derive utility weights from a small sample (16) which were used to adjust length of life to reflect quality, in terms of a "quality adjusted life year" (QALY).

RESULTS

Chemotherapy increases the total cost of treating a patient with colon cancer by $7000, from $6000 to $13,000. Incorporating quality of life reduced the extra benefit gained from the chemotherapy from 2.4 life years to 0.4 QALYs. Thus the result is a cost of $17,500 to achieve an extra QALY from this particular treatment.

CONCLUSIONS

The results of this analysis are only tentative, as the quality of life descriptions were not measured over time but from a cross-sectional survey of patients, and the valuations of health states were derived from a small sample. However, we believe them to be indicative, and conclude that it is perhaps more appropriate for the use of chemotherapy to be an option rather than standard treatment until further research on these aspects is complete.