Background: Despite some evidence that age does not meaningfully influence the efficacy or toxicity of cancer treatment, older patients tend to receive less comprehensive cancer therapies.
Purpose: We conducted a population-based study to evaluate the selection of cancer treatment among the elderly.
Methods: Between September 1 and November 30, 1990, we interviewed by telephone a sample of 628 female Wisconsin residents recently diagnosed with breast (507) or colorectal (121) cancer. The women, aged 20-74 at the time of diagnosis, were identified through Wisconsin's statewide tumor registry. The approximately 30-minute long telephone interview, part of a larger study of cancer etiology, included questions on treatment history, physician specialty, and reasons for the selection of specific therapies. Analyses compared the proportion of subjects with various treatment characteristics according to age (< 65 and > or = 65 years). In evaluating the effect of age on selected therapies, we adjusted summary proportions for stage of disease using the indirect method. The Mantel-Haenszel chi square statistic was used to evaluate statistical significance of the differences in proportions.
Results: After adjusting for stage of disease at diagnosis, substantial variation was observed in cancer treatment according to age for both breast and colorectal cancer. Older women (> or = 65 years) with breast cancer were less likely than younger women (< 65 years) to have received conservative surgery, radiation, and adjuvant therapy. Older women were, in fact, more likely than younger women to accept mastectomy (P = .03). Consultation with a medical or radiation oncologist was less common among older than younger patients (57% versus 73%). Older women were also less likely to have alternative therapies presented to them (19% versus 31%). While older patients were less likely to have been offered adjuvant treatments, like chemotherapy (P < .01), they were also more likely than younger women to reject these treatments when offered (P = .01). These differences were observed in both breast and colorectal cancer patients. Regardless of age, the most common reasons for not selecting treatments were physicians' recommendations and the desire for more comprehensive treatment. Concern about side effects, however, was more frequently reported by older women (P = .07).
Conclusion and implication: Patients' ages influence the choice of treatment. Physicians offer older women with cancer different treatments from those offered to younger women and are less likely to recommend specialist consultation. Physicians' advice and description of toxicity may influence patients' selection of treatment. However, older patients' concerns about the consequences of cancer treatment may also influence treatment choice.