Single cell profiling of female breast fibroadenoma reveals distinct epithelial cell compositions and therapeutic targets.

Fibroadenomas (FAs) are the most common breast tumors in women. No pharmacological agents are currently approved for FA intervention owing to its unclear mechanisms and a shortage of reproducible human models. Here, using single-cell RNA sequencing of human FAs and normal breast tissues, we observe distinct cellular composition and epithelial structural changes in FAs. Interestingly, epithelial cells exhibit hormone-responsive functional signatures and synchronous activation of estrogen-sensitive and hormone-resistant mechanisms (ERBB2, BCL2 and CCND1 pathways). We develop a human expandable FA organoid system and observe that most organoids seem to be resistant to tamoxifen. Individualized combinations of tamoxifen with ERBB2, BCL2 or CCND1 inhibitors could significantly suppress the viability of tamoxifen-resistant organoids. Thus, our study presents an overview of human FA at single-cell resolution that outlines the structural and functional differences between FA and normal breast epithelium and, in particular, provides a potential therapeutic strategy for breast FAs.

Multiple cholesterol granulomas of the breast: A case report and review of the literature.

RATIONALE: Cholesterol granuloma of the breast is a rare disease defined as chronic reactive inflammation of cholesterol crystals and foreign body giant cells. This disease can mimic breast cancer in the clinic as painless palpable hard nodules, and imaging shows irregular hypoechoic nodules with unclear boundaries. Therefore, the uncommon lesions can be easily misdiagnosed as breast cancer. Meanwhile, it can be easily neglected by clinicians because of poor understanding. PATIENT CONCERNS: In this report, we present a rare case of multiple cholesterol granulomas of the breast, which was analyzed retrospectively and combined with all 11 relevant available studies in the last 50 years. INTERVENTIONS: The patient had undergone multiple breast imaging inspections for breast nodules and had the local resection of nodules. DIAGNOSES: The patient was confirmed to have a final diagnosis of benign cholesterol granulomas but was initially considered as breast cancer. OUTCOMES: The patient did not complain of discomfort after surgery, and ultrasound reexamination 5 months after surgery showed no recurrence. LESSONS: By retrospective analysis, dynamic contrast-enhanced magnetic resonance imaging and core needle biopsy can synergistically help clinicians distinguish it from other breast disease. To raise awareness of such a rare disease and reduce related misdiagnoses, we summarize the characteristics of cholesterol granulomas and recommend appropriate novel diagnosis and treatment regimens for patients with cholesterol granulomas.