Abstract

PURPOSE:

Third-generation aromatase inhibitors have been widely used in postmenopausal women for the adjuvant treatment of hormone receptor-positive breast cancer. As aromatase inhibitors work by inhibiting the conversion of androgens to estrogens in adipose tissue, we hypothesized that anastrozole may be more effective in women with a high body mass index (BMI).

PATIENTS AND METHODS:

The Arimidex, Tamoxifen Alone or in Combination (ATAC) study was a double-blind randomized clinical trial in which postmenopausal women with early-stage breast cancer were randomly assigned to receive oral daily anastrozole (1 mg) alone, tamoxifen (20 mg) alone, or the combination in a double-blind fashion. Analyses were based on the 100-month median follow-up for women with hormone receptor-positive breast cancers (estrogen [ER] and/or progesterone [PgR] positive). Here, we investigate the impact of BMI on recurrence and the relative benefit of anastrozole versus tamoxifen according to baseline BMI. Results Overall, women with a high BMI (BMI > 35 kg/m(2)) at baseline had more recurrences than those women with a low BMI (BMI < 23 kg/m(2); adjusted hazard ratio [HR], 1.39; 95% CI, 1.06 to 1.82; P(heterogeneity) = .03) and significantly more distant recurrences (adjusted HR, 1.46; 95% CI, 1.07 to 1.61; P(heterogeneity) = .01). Overall, the relative benefit of anastrozole versus tamoxifen was nonsignificantly better in thin women compared to overweight women.

CONCLUSION:

These results confirm the poorer prognosis of obese women with early-stage breast cancer. Recurrence rates were lower for anastrozole than tamoxifen for all BMI quintiles. Our results suggest that the relative efficacy of anastrozole compared to tamoxifen is greater in thin postmenopausal women and higher doses or more complete inhibitors might be more effective in overweight women, but this requires independent confirmation.

Abstract

PURPOSE:

Regular physical activity reduces the risk of developing colon cancer, however, its influence on patients with established disease is unknown.

PATIENTS AND METHODS:

We conducted a prospective observational study of 832 patients with stage III colon cancer enrolled in a randomized adjuvant chemotherapy trial. Patients reported on various recreational physical activities approximately 6 months after completion of therapy and were observed for recurrence or death. To minimize bias by occult recurrence, we excluded patients who experienced recurrence or died within 90 days of their physical activity assessment.

RESULTS:

Compared with patients engaged in less than three metabolic equivalent task (MET) -hours per week of physical activity, the adjusted hazard ratio for disease-free survival was 0.51 (95% CI, 0.26 to 0.97) for 18 to 26.9 MET-hours per week and 0.55 (95% CI, 0.33 to 0.91) for 27 or more MET-hours per week. The adjusted P for trend was .01. Postdiagnosis activity was associated with similar improvements in recurrence-free survival (P for trend = .03) and overall survival (P for trend = .01). The benefit associated with physical activity was not significantly modified by sex, body mass index, number of positive lymph nodes, age, baseline performance status, or chemotherapy received. Moreover, the benefit remained unchanged even after excluding participants who developed cancer recurrence or died within 6 months of activity assessment.

CONCLUSION:

Beyond surgical resection and postoperative adjuvant chemotherapy for stage III colon cancer, for patients who survive and are recurrence free approximately 6 months after adjuvant chemotherapy, physical activity appears to reduce the risk of cancer recurrence and mortality.