A 52-year-old woman from Mumbai undergoes mammography for screening and is found to have a 1.5 cm mass in the upper outer quadrant of the left breast with microcalcifications. Core needle biopsy confirms invasive lobular carcinoma (ILC). Clinical examination reveals no skin changes, no palpable axillary lymph nodes, and the mass is mobile. Staging investigations (chest X-ray, abdominal ultrasound, bone scan) are unremarkable. The patient is counseled about treatment options. What is the most appropriate surgical management?

Explanation

## Clinical Staging This patient presents with early-stage breast cancer (T1N0M0) based on: - Tumor size: 1.5 cm (T1 disease) - No skin involvement or chest wall fixation - No palpable axillary lymph nodes (cN0) - Mobile mass (not fixed) - No distant metastases (M0) ## Eligibility for Breast-Conserving Therapy (BCT) **Key Point:** BCT is the preferred surgical option for early-stage breast cancer (T1–T2, N0–N1) when adequate margins can be achieved and whole-breast radiation therapy is feasible. **High-Yield:** BCT offers equivalent oncologic outcomes to mastectomy in early-stage disease while preserving breast tissue and improving cosmesis. It is now the standard of care in developed countries and increasingly adopted in India for eligible patients. ## Criteria Met for BCT | Criterion | Status | Assessment | | --- | --- | --- | | Tumor size | 1.5 cm | T1 — eligible | | Skin involvement | None | No dimpling or ulceration | | Chest wall fixation | No | Mobile mass | | Nodal status | cN0 | No palpable nodes | | Distant metastases | None | M0 | | Histology | ILC | No contraindication | | Radiation feasibility | Assumed available | Required for BCT | **Clinical Pearl:** Invasive lobular carcinoma (ILC) is not a contraindication to BCT. While ILC has a higher risk of contralateral breast cancer and multifocal disease, it does not preclude BCT if margins are adequate. ## Surgical Technique for BCT 1. **Wide local excision (lumpectomy):** Removal of tumor with 1–2 cm margins of normal tissue 2. **Sentinel lymph node biopsy (SLNB):** Identifies and removes sentinel node(s); if negative, full axillary dissection is avoided 3. **Whole-breast radiation therapy:** 40–50 Gy over 5–6 weeks (mandatory after BCT) **Mnemonic:** BCT = **B**reast **C**onserving **T**herapy = Lumpectomy + SLNB + Radiation ## Why SLNB Over Axillary Lymph Node Dissection (ALND)? **High-Yield:** In clinically node-negative (cN0) patients, SLNB has 95–98% accuracy and avoids the morbidity of full ALND (lymphedema, seroma, nerve injury). If sentinel node is negative, no further axillary treatment is needed. ## Why Not Mastectomy? **Key Point:** Mastectomy is overtreatment for T1N0 disease. Randomized trials (NSABP B-06, EORTC 10801) have shown no survival difference between BCT and mastectomy in early-stage disease. BCT is now preferred when feasible. ## Why Not Neoadjuvant Chemotherapy? Neoadjuvant chemotherapy is indicated in locally advanced disease (T3–T4 or N2–N3) to improve resectability. This patient has early-stage disease and does not require neoadjuvant therapy; primary surgery is appropriate. [cite:Sabiston Textbook of Surgery Ch 36; NCCN Breast Cancer Guidelines 2023]