TREATMENT OF EARLY-STAGE BREAST-CANCER IN THE ELDERLY - A HEALTH-OUTCOME-BASED APPROACH

Purpose. To evaluate the post-lumpectomy treatment of a nonpalpable, s tage 1, T1b tumor, mammographically detected, in a 74-year-old woman w ithout comorbidities. Methods. A Markov process, through 120 monthly c ycles, was used to model patient progression through a treatment progr am, employing literature data and a health-outcome utility. Treatments considered were: observation; radiation totaling 5,000 cGy over six w eeks; tamoxifen, 20 mg/day, for five years; simple mastectomy; and rad iation therapy plus tamoxifen. Health states included absence of disea se (NED), loco-regional recurrence, distant metastasis, age-sex-race ( ASR)-adjusted death, cancer mortality, treatment complications, and po st-mastectomy death. Transition probabilities were established from th e literature. Health-state utilities were determined from the response s of health care professionals to a basic reference gamble. Results. Q uality-adjusted life years (QALYs) were determined to be 8.19 for radi ation plus tamoxifen, decreasing to 8.04 for mastectomy, a difference of only a 0.15 years (1.8 months). Sensitivity analysis, however, show ed relative stability in the ranking among treatment options. Conclusi on. Although the model showed little difference between QALYs with the treatments, the combination of radiation and tamoxifen provides the o ptimal therapy for this case.