Table 1 Eligibility and exclusion criteria of the study

Inclusion criteria

 - Age ≥ 45 years

 - Stage I-IIA histologically confirmed breast carcinoma

 - Tumor-free (at least 2 mm or more) inked histologic margins at surgical resection.

Clinical exclusion criteria

 - Pregnancy

 - Collagen vascular disease

 - Aesthetic additive prostheses

 - Severe cardiac, pulmonary and liver diseases

 - Psychiatric illness compromising the correct acquisition of informed consent

Oncologic exclusion criteria

 - Invasive lobular or multicentric carcinoma

 - Extensive associated non-invasive ductal carcinoma (synchronous or previous)

 - Peritumoral vascular invasion (> 3 vessels)

 - BRCA mutation carriers

 - More than 4 involved axillary lymph nodes

 - Distant metastasis

 - Non-epithelial malignancies of the breast

 - Synchronous contralateral invasive carcinoma

 - Paget disease, history of previous malignancy (except non-melanoma skin cancers and in situ oral cavity and cervix carcinoma)