Adenoid cystic carcinoma of the breast and intraoperative electron radiotherapy: single case report and review of literature.

Adenoid cystic carcinoma (ACC) of the breast is a very rare neoplasm. It presents a triple-negative phenotype in most cases, but its prognosis is generally considered to be better than other breast cancers with the same immunohistochemical pattern. Due to its controversial features, no data are available in the literature regarding a consensus approach for ACC treatment, especially for subtypes with worse prognosis like solid basaloid ACC. We present for the first time a rare case of ACC with multifocal presentation treated with breast-conservative surgery and intraoperative electron radiotherapy, thus supporting this treatment of ACC in selected patients like young women affected by the solid basaloid variant who commonly present a worse prognosis. In this case, no local or systemic recurrence was detected after 30 months of follow-up.

Plain language summary Breast cancer is a large group of tumors with different and specific features. Because of its variety, no univocal guidelines are available to medical doctors for the treatment of this disease, especially for the rarest presentations. This is the case for breast adenoid cystic carcinoma, a rare tumor which accounts for less than 0.1% of all breast cancers and about which few instructions for its therapeutic approach or prognosis are described in the literature. This case report describes our experience using partial breast resection in combination with a specific protocol of intraoperative radiation for the treatment of an aggressive variant of breast adenoid cystic carcinoma. Good cosmetic results and no recurrence of the disease were shown, suggesting that a conservative approach could avoid unnecessary total breast resection as supported by some previous authors.

B3 lesions of the breast and cancer risk. A single-centre experience.

BACKGROUND: Breast lesions of uncertain malignant potential, also known as B3 lesions, represent a heterogeneous group of tumors with variable malignancy risk. Surgical excision should be considered depending on clinical, radiological and histological features, family history and following informed consent. The aim of the present paper is to evaluate the positive predictive value (PPV) of diagnosis of malignancy in surgically excised B3 lesions in order to identify possible predictive upgrade criteria. We mainly focused on disclosing the concordance rate between tissue biopsy and final surgical pathology and correlation between radiology and pathology. METHODS: Between January 2018 and December 2021, 83 patients undergoing ultrasound guided tru-cut needle biopsy or VABB with a B3 diagnosis and surgical excision following multidisciplinary discussion were retrospectively reviewed in our Breast Unit. RESULTS: Out of a total of 83 cases with a B3 diagnosis before surgery, atypical ductal hyperplasia accounted for 29/83 cases(34.93%) and the most part of patients presented nodular lesions (n = 34/83, 40.96%). Among the 15 cases of malignancy detected after surgery, micro calcifications were registered in 53.3% of patients on mammography (n = 8/15). CONCLUSION: We assessed the correlation between radiological and pathological criteria in order to guide risk stratification and ensure adequate patient management. Correspondence between histological diagnosis, imaging and type of diagnostic biopsy were evaluated. No statistically significant predictors were identified for the parameters assessed in our study. KEY WORDS: B3 Breast Lesions, Lesions of Uncertains Malignant Potential, Mammografic Distortion, Screen Detected Breast Lesion.