Pathologic quiz case: a 62-year-old woman with a 4.5-cm nodule in the right breast. Lipid-rich breast carcinoma

Lipid-Rich Carcinoma of the Breast With Unusual Clinical and Histopathological Features

Lipid-rich carcinoma of the breast is a rare form of invasive breast carcinoma of special type. Most cases are grade 3, hormone receptor negative, and associated with aggressive clinical behavior. We report an unusual case of lipid-rich carcinoma with morphological and immunophenotypical features different from those of cases reported so far in the literature. The index case underscores the fact that there is no consensus with regard to the exact nature of this tumor. Hence, larger studies are needed to draw meaningful conclusions.

Lipid-rich carcinoma of the breast: A report of two cases and a literature review

Lipid-rich carcinoma of the breast is extremely rare with no standard guidelines for treatment with poor patient prognosis. In the present study, the clinical features, imaging results, pathology, immunohistochemistry, treatment and prognoses of two patients with lipid-rich carcinoma of the breast were analyzed. Two patients were admitted to the Yantai Yuhuangding Hospital Affiliated to the Medical College of Qingdao University (Yantai, Shandong, China) for examination of a palpable mass in the breast. Enlarged lymph nodes were found in the axilla of each patient. The results of mammography and echography imaging suggested the presence of malignancy. A modified radical mastectomy was performed in each patient, and pathological examination revealed atypical large vacuolated cells arranged in clusters and confirmed lipid-rich carcinoma and lymph node metastases. The tumor tissue of patient one was immunohistochemically positive for estrogen receptor (ER), p53, p120 and E-cadherin, and negative for progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER-2), with a Ki-67 labeling index of 50%. The tumor tissue of patient two was immunohistochemically positive for p53, and negative for ER, PR, HER-2 and cytokeratin 5/6, with a Ki-67 labeling index of 30%. Post-surgery, patient one was administered chemotherapy for six cycles, radiotherapy and endocrine therapy in the form of anastrozole. Patient two was administered three cycles of chemotherapy without radiotherapy. Subsequent to being followed up for 25 months and 13 months, respectively, there was no evidence of recurrence or distant metastasis in patient one or two, respectively.

Unusual occurrence of rare lipid-rich carcinoma and conventional invasive ductal carcinoma in the one breast: case report

A 56-year-old woman noticed a palpable mass in her left breast during self-examination. Patient was admitted to our hospital and malignant bifocal tumour was diagnosed by ultrasonography, digital mammography, magnetic resonance, and core-cut biopsy. The patient underwent planned conservative surgery (biquadrantectomy) with a sentinel node examination, but after results of the frozen section with positive resection margins and positive sentinel lymph nodes subsequent mastectomy with axillary lymph node dissection were realized. Histology in the resection specimen revealed two isolated and distinct tumours. One of the lesions represented conventional invasive ductal carcinoma of histological grade 3, and the second tumour was evaluated as invasive lipid-rich carcinoma, containing tumour cells with clear and foamy cytoplasm. Lipids in neoplastic cells were detected by Oil Red O staining and ultrastructural examination. Immunohistochemical analysis of both carcinomas was almost identical with negative steroid receptors, positive staining of HER-2, and p53 and with high proliferation activity (Ki-67). Mastectomy specimen contained residual foci of invasive ductal carcinoma and dissected axillary lymph nodes were free of metastasis. Patient underwent first cycles of chemotherapy with paclitaxel and Herceptin together with local radiotherapy and two month after surgery is without any evidence of the disease.

Lipid-rich carcinoma of the breast clinicopathologic analysis of 17 cases

Lipid-rich carcinoma of the breast is a rare variant of breast cancer, accounted for <1% of all breast malignant tumors. We retrospectively analyzed the clinicopathologic characteristics of lipid-rich carcinomas of the breast. A panel of estrogen receptor, progesterone receptor, human epidermal growth factor receptor-2 (HER-2), cytokeratin (CK) 5/6, CK14, and P63 was prepared for detection of lipid-rich carcinoma. Fluorescence in situ hybridization and electron microscope assays were performed for detecting HER-2 gene amplification and ultrastructure. Survival analysis were carried out using Kaplan-Meier and Cox regression methods. Receiver operating characteristic test was also performed. Estrogen receptor, CK5/6, CK14, and P63 were negative. Progesterone receptor (1/17) and HER-2 (17/17) were positive. HER-2 gene amplification was detected in all included cases (ratio values >2.2). Ultrastructure showed fat droplet and electron-dense material in the cytoplasm. Statistical differences were detected among survival and age (P = .033), histologic grade (P = .004), lymph node involvement (P = .001), and HER-2 expression (P = .002), respectively, using Kaplan-Meier methods. Statistical differences were also detected (P = .017) using Cox regression methods. Receiver operating characteristic test displayed significant statistical differences; the prognosis had a correlation between HER-2 expression "+" and HER-2 expression "++" (P = .004). Lipid-rich carcinoma of the breast was an HER-2 overexpressing subtype of the breast carcinoma. Survival of lipid-rich carcinoma might be associated with age, histologic grade, lymph node involvement, and HER-2. The HER-2 expression, however, might play an important role in predicting the prognosis of lipid-rich carcinoma of the breast.

Lipid-rich histology in a basal-type immuno-profile breast carcinoma: a clinicopathological histochemical and immunohistochemical analysis of a case

We describe the clinicopathological and morphological features of an unusual breast carcinoma classifiable as a lipid-rich variant of ductal invasive carcinoma, with a basal-type immunohistochemical profile. Basal-type breast cancers show no hormonal receptor expression, rarely over-express HER-2 but exhibit molecular high weight cytokeratins, EGFR and c-kit positivity. Special stains and histochemistry tests were used to elucidate the nature of vescicles in the neoplastic cells. Sudan IV was performed on formalin-fixed tissue. Commercially available antibodies tested were: ER, PgR, EGFR, HER2, c-kit, high molecular weight cytokeratins. Cytoplasmic lipids were highlighted as red-orange droplets on Sudan IV staining. As for immunohistochemistry, the tumor showed no reactivity to ER, PgR and HER2 (triple negative), and diffuse and strong positivity to high weight cytokeratins, EGFR and c-kit, such as a basal-type breast carcinoma. A basaloid phenotype in a lipid-rich carcinoma has not been previously reported.

Cytomorphology of Rare Malignant Tumors of the Breast

This article reviews cytomorphology of rare malignant tumors of the breast: squamous carcinoma, metaplastic carcinoma, adenoid cystic carcinoma, apocrine carcinoma, secretory carcinoma, lipid-rich carcinoma, and carcinoma with choriocarcinomatous features. It is important to bear in mind the cytomorphology and diagnosis of rare malignant tumors of the breast in analysis of breast fine needle aspiration smears. Although rare, these malignant tumors can be diagnosed by the cytomorphological characteristics, and should be included in the differential diagnoses of breast neoplasms.