Locoregional Control With Radiotherapy of Breast Cancer Patients With MACrometastases Treated With MAstectomy (MACMA)

Locoregional Control With Radiotherapy of cT1-2N0 Invasive Breast Cancer Patients With MACrometastases in the Sentinel Node Treated With MAstectomy: a Multi-center Observational Study

Status

Active, not recruiting

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT06378294

Acronym

MACMA

Enrollment

Registered

2024-04-22

Start date

2021-04-20

Completion date

2029-12-31

Last updated

2025-03-20

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Breast Cancer

Keywords

axillary radiotherapy, mastectomy, sentinel lymph node biopsy

Brief summary

Sentinel lymph node biopsy (SLNB) is the standard procedure to stage the axilla in clinically node-negative invasive breast cancer (IBC) patients undergoing upfront surgery. The ACOSOG-Z0011 and the AMAROS trial demonstrated that SLNB with or without radiotherapy provided equivalent local control and survival to axillary lymph node dissection (ALND) in early-stage breast cancer patients with 1 or 2 positive SLNs. However, the ACOSOG-Z0011 trial did not included patients treated with mastectomy, and the AMAROS trial only included 17% of mastectomy patients. The investigators conduct an observational cohort study of early stage breast cancer patients receiving upfront mastectomy with 1 or 2 macrometastases after SLNB. The study aim to demonstrate a 5-year disease-free survival of not less than 80% when ALND is omitted and replaced by axillary radiotherapy, and determine the axillary recurrence rate.

Detailed description

This is a multi-center, prospective study with an estimated sample size of 60 early-stage IBC patients. Clinically node-negative T1-2 IBC patients undergoing mastectomy with up to 2 macrometases after SLNB will be informed about this study. Patients will be checked with annual mammography and clinical examination. The axilla will be checked with ultrasound at 3 and 5 years of the surgery. After surgery, patients will receive axillary radiotherapy, but no ALND, and adjuvant systemic treatment based on international guidelines.

Interventions

PROCEDUREMastectomy

Adjuvant postmastectomy radiotherapy

Study design

Observational model

COHORT

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

FEMALE

Age

18 Years to 85 Years

Inclusion criteria

* Patients with T1-2 primary invasive breast cancer * No suspicion of lymph node involvement prior to sentinel lymph node biopsy * Patients undergoing upfront mastectomy * Macrometastasis in not more than 2 lymph nodes at sentinel lymph node biopsy * Patients treated with adjuvant axillary radiotherapy

Exclusion criteria

* Prior history of invasive breast cancer * Medical contraindication for radiotherapy * Medical contraindication for adjuvant systemic treatment * Planned neoadjuvant systemic treatment * Distant metastasis at initial diagnosis * Inability to absorb or understand the meaning of the study information

Design outcomes

Primary

Measure	Time frame	Description
Disease-free survival	3 and 5 years	recurrence in the ipsilateral breast/thoracic wall, regional recurrence, distant recurrence or death
Axillary recurrence rate	3 and 5 years	recurrence rate in the ipsilateral axillary lymph nodes

Secondary

Measure	Time frame	Description
Overall survival	5 years	any cause of death as event

Countries

Spain

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026