A 55-year-old woman undergoes modified radical mastectomy for a 6 cm grade 3 invasive ductal carcinoma. Final histopathology shows metastasis in 9 of 17 axillary lymph nodes, ER-positive, HER2-negative status. In addition to systemic therapy, what locoregional treatment is indicated?
- A No further locoregional therapy as mastectomy was performed
- B Radiotherapy to the axilla only
- C Post-mastectomy radiotherapy to the chest wall and regional nodes ✓
- D Brachytherapy boost to the internal mammary chain
Correct answer: C. Post-mastectomy radiotherapy to the chest wall and regional nodes
Explanation
Post-mastectomy radiotherapy is clearly indicated for T3 or T4 primaries and for four or more positive axillary nodes, as shown by EBCTCG meta-analyses demonstrating reduced locoregional recurrence and improved survival. This patient fulfils both criteria with a 6 cm tumour and nine positive nodes, so irradiation of the chest wall and draining nodal basins is standard alongside systemic endocrine therapy. Omitting radiation would substantially increase her risk of chest wall recurrence.
Reference: Bailey and Love's Short Practice of Surgery, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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