Lymphedema Evaluation After Adjuvant Hypofractionated Radiotherapy for 1-2 Macrometastatic Sentinel Lymph Nodes

AXILL-ART: Lymphedema Evaluation After Adjuvant Hypofractionated Radiotherapy for 1-2 Macrometastatic Sentinel Lymph Nodes Without Axillary Dissection in Breast Cancer Conservative Surgery: Observational Study

In this observational prospective studi patients with invasive breast cancer no more than 5 cm and clinically node negative, scheduled for conservative surgery and Sentinel Node Biopsy (SNB), are enrolled in the protocol if they have 1-2 sentinel lymphnodes (SLNs) with macrometastases. SLN status will be checked on definitive sections.

In recent years, breast oncologic surgery has aimed to omit axillary dissection in cases where no more than two sentinel lymph nodes are positive, particularly when complementary radiotherapy to the whole breast is planned.

Radiation therapy to the axillary lymph nodes ensures excellent locoregional control in patients with primary tumor no more than 5 centimeter and 1-2 macrometastatic sentinel lymph nodes, and appears to carry fewer side effects than axillary dissection.

Arm lymphedema is indeed one of the most well-known long-term complications of breast cancer treatment, impacting the quality of life for patients undergoing lymphadenectomy. In this scenario, the study proposes a treatment of hypofractionated intensity-modulated radiotherapy (IMRT) to the breast and axillary lymph nodes with the aim of further containing the risk of developing ipsilateral arm lymphedema. IMRT improves the dosimetric profile of surrounding organs at risk in the treated area, with better dose conformity to the target volume compared to tangential fields used in conventional 3D conformal techniques (as employed in most trials described so far).

Inclusion Criteria:

1. Histological proven invasive breast cancer
2. Breast conserving surgery with no axillary dissection
3. Tumor dimension no more then 5 cm and no more than 2 positive sentinel node

5) Negative surgical margin (no tumor cell on ink) 6) Performance Status (PS) <2 7) Age >18 8) Written informed consent

Exclusion Criteria:

1. Previous thoracic RT
2. Mixed connective disorders
3. Distant metastases
4. Severe lung or cardiac diseases
5. Neoadjuvant systemic therapies
6. Axillary dissection
7. No surgical axillary investigation
8. Mastectomy
9. Axillary micrometastasis or isolated tumor cell