The ATAC trial established that, compared to tamoxifen, anastrozole as adjuvant therapy in postmenopausal hormone receptor-positive breast cancer provides which advantage?

• A Superior overall survival in HER2-positive subgroup
• B Significantly fewer endometrial cancers and thromboembolic events ✓
• C Equivalent efficacy with less bone mineral density loss
• D Improved benefit in node-negative compared to node-positive disease

Explanation

The ATAC (Arimidex, Tamoxifen, Alone or in Combination) trial demonstrated that anastrozole produced significantly fewer endometrial cancers (an estrogen-receptor-positive tissue effect of tamoxifen) and fewer thromboembolic events compared with tamoxifen, while achieving superior disease-free survival. Bone mineral density loss is actually greater with aromatase inhibitors than tamoxifen, making option C incorrect. The trial enrolled both node-positive and node-negative patients without demonstrating a differential benefit by nodal status.

Reference: Bailey & Love's Short Practice of Surgery, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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