Third International Consensus Conference on lesions of uncertain malignant potential in the breast (B3 lesions).

The heterogeneous group of B3 lesions in the breast harbors lesions with different malignant potential and progression risk. As several studies about B3 lesions have been published since the last Consensus in 2018, the 3rd International Consensus Conference discussed the six most relevant B3 lesions (atypical ductal hyperplasia (ADH), flat epithelial atypia (FEA), classical lobular neoplasia (LN), radial scar (RS), papillary lesions (PL) without atypia, and phyllodes tumors (PT)) and made recommendations for diagnostic and therapeutic approaches. Following a presentation of current data of each B3 lesion, the international and interdisciplinary panel of 33 specialists and key opinion leaders voted on the recommendations for further management after core-needle biopsy (CNB) and vacuum-assisted biopsy (VAB). In case of B3 lesion diagnosis on CNB, OE was recommended in ADH and PT, whereas in the other B3 lesions, vacuum-assisted excision was considered an equivalent alternative to OE. In ADH, most panelists (76%) recommended an open excision (OE) after diagnosis on VAB, whereas observation after a complete VAB-removal on imaging was accepted by 34%. In LN, the majority of the panel (90%) preferred observation following complete VAB-removal. Results were similar in RS (82%), PL (100%), and FEA (100%). In benign PT, a slim majority (55%) also recommended an observation after a complete VAB-removal. VAB with subsequent active surveillance can replace an open surgical intervention for most B3 lesions (RS, FEA, PL, PT, and LN). Compared to previous recommendations, there is an increasing trend to a de-escalating strategy in classical LN. Due to the higher risk of upgrade into malignancy, OE remains the preferred approach after the diagnosis of ADH.

A Rare Case of Breast Malignancy in an Adolescent Woman: Lessons Learned from Diagnosis and Management.

INTRODUCTION: Primary breast malignancy in adolescent women is very rare and differs in several aspects from findings in adult women. CASE PRESENTATION: A young woman aged 16 years presented with a locally aggressive breast tumor. The patient received cisplatin-based chemotherapy followed by tumor resection assuming a diagnosis of germ cell tumor. Four months later, she developed locally recurrent disease and underwent a mastectomy. No definite diagnosis was agreed upon despite intensive pathological workup. Subsequent management consisted of follow-up only and the patient remains in complete remission 9 years later. CONCLUSION: This case demonstrates the difficulty of diagnosis and management of rare malignancies in adolescents, and highlights the importance of international and interdisciplinary collaboration in diagnosis and clinical decision-making.