Aromatase inhibitors in the inhibition of estrogen and breast cancer patients

Recent study reported that the effectiveness of PPID aromatase inhibitors (AIS), anastrozole and letrozole in women with higher BMI lower than tamoxifen. Hypothesis may be due to a higher BMI would reduce the inhibition of these drugs on the aromatase and estrogen levels, increased aromatase inhibitors (AIS) the amount of anastrozole and letrozole may be able to overcome this problem. So in order to anastrozole to letrozole and other aromatase inhibitors (AIS) on the inhibition of PPIE plasma estradiol and estrone sulfate levels really early estrogen receptor (ER)-positive postmenopausal breast cancer patients Body mass index (BMI), Elizabeth J. Folkerd and others from the UK Royal Marsden NHS Foundation Trust has been studied. The study recently published online in JCO.The study included 44 postmenopausal breast PPIF cancer patients, these patients have accepted the three months, anastrozole (1 mg daily), letrozole (2.5 mg) three months of treatment (or starting letrozole treatment, anastrozole azole therapy). The researchers used a highly sensitive radioimmunoassay measuring the level of estradiol and estrone sulfate in the plasma of these patients. And then assess anastrozole to letrozole on the inhibition of estrogen and the correlation between BMI.

The final study found that baseline PPIG estradiol and estrone sulfate levels and BMI were significantly correlated (respectively r = 0.57, P <0.001 and r = 0.38, p = 0.006). Higher in patients with estrogen levels the patients received anastrozole and letrozole treatment, BMI was also higher, although only letrozole reach significant difference (estradiol and estrone sulfate, respectively, R = 0.35, P = .013 and r = 0.30, P = 0.035). In this study, the inhibitory PPIH effect of letrozole both estrogen in each BMI patients is stronger than anastrozole.Finally, a conclusion: In the ER-positive early postmenopausal breast cancer patients, anastrozole and letrozole inhibit the level of the patient's BMI is related to plasma estradiol and estrone sulfate.