Change in bone mineral density during adjuvant chemotherapy for early-stage breast cancer
Menée au Danemark auprès de 97 patientes atteintes d'un cancer du sein de stade précoce (âge moyen : 53 ans), cette étude de cohorte prospective évalue les effets d'une chimiothérapie adjuvante sur les changements de densité minérale osseuse, 4 mois après la fin du traitement
Purpose : Adjuvant chemotherapy has been associated with loss of bone mineral density (BMD) either as a direct effect or due to glucocorticoids used as supportive care medication. A prospective cohort study was conducted to evaluate changes in BMD from baseline to right after completion of chemotherapy, i.e., 4 months. Methods : Dual-imaging X-ray absorptiometry (DXA) was performed at baseline and after completing anthracycline- and taxane-based chemotherapy to measure BMD in the spine, hip, and forearm in early-stage breast cancer patients. High-dose prednisolone was used at three weekly intervals to reduce nausea and vomiting. Patients were advised a daily calcium/vitamin D supplement. Linear regression was used to assess mean percentage change in BMD and 95 % confidence intervals (95 % CI) according to doses of prednisolone, menopausal status, smoking, and BMI. Results : Eight patients were excluded: seven because of initiation of bisphosphonate treatment due to osteoporosis at baseline, and one had non-interpretable DXA. The final cohort included 97 patients with a mean age of 53 years (range 34–72). Mean cumulative prednisolone dose was 1308 mg (95 % CI 1255; 1362). BMD increased 1.36 % (95 % CI 0.7; 2.0, p < 0.001) in the spine and 1.27 % (95 % CI 0.9; 1.7, p < 0.001) in the hip. Forearm BMD did not change. Postmenopausal women had increases in spine BMD of 2.35 % (95 % CI 1.1; 3.6, p < 0.001) compared to premenopausal women. The spine BMD of current smokers decreased 1.67 % (95 % CI −3.3; −0.1, p = 0.04) compared to never/former smokers. Conclusions : Adjuvant chemotherapy supplemented with prednisolone was not associated with loss of BMD. Postmenopausal women gained bone mass, whereas current smokers lost bone mass.