Lipid-Secreting Carcinoma of the Breast: A Case Report and Review of the Literature

The clinical and pathological characteristics of lipid-rich carcinoma of the breast: an analysis of 98 published patients

BACKGROUND

Due to the small number of cases and few literature reports, the clinical treatment and prognosis of lipid-rich carcinoma of the breast are not summarized, which will lead to misdiagnosis and mistreatment and delay the patient's condition. This study collected published case reports and analyzed the clinical characteristics of lipid-rich carcinoma of the breast in order to provide reference for early diagnosis and treatment of the disease.

METHODS

We performed a search using the PubMed, ClinicalTrials.gov, Embase, Cochrane Library, and China National Knowledge Infrastructure (CNKI) databases for publicly published case reports of lipid-rich carcinoma of the breast and obtained basic information of the patients such as country, age, sex, onset site, surgical method, pathology, postoperative treatment, follow-up time, and outcome (Table 9). The data were analyzed using Statistical Product Service Solutions (SPSS).

RESULTS

The mean age of the patients at diagnosis was 52.79 years and the median age was 53 years. Breast masses were the main clinical manifestations, with the upper outer quadrant (53.42%) being the most common. The treatment for lipid-rich carcinoma of the breast is mainly surgery plus postoperative adjuvant radiotherapy and chemotherapy. According to the results of this study, the surgical method recommended modified radical mastectomy (46.59%). Lymph node metastasis was found in 50.60% of the patients at the time of the first diagnosis. Patients who received postoperative adjuvant chemotherapy and radiotherapy had the highest disease-free survival and overall survival.

CONCLUSION

Lipid-rich carcinoma of the breast has a short course of disease and early lymphatic or blood metastasis, and its prognosis is poor. In this study, we summarize the clinical and pathological characteristics to provide ideas for the early diagnosis and treatment of lipid-rich carcinoma of the breast.

Rare Breast Cancer Subtypes

PURPOSE OF REVIEW

Breast cancer is a collection of diseases including the more common invasive ductal and lobular carcinomas and rarer subtypes of breast cancer. This review summarizes the features of rare breast cancers.

RECENT FINDINGS

Each of the rare tumors has defined pathological and clinical features that impact treatment recommendations. In this review, we summarize these for each rare type of breast cancer and where available we include molecular features of each tumor. Rare subtypes of breast cancer each have unique features. In many cases, data is limited for the optimal treatment approaches.

Lipid-rich carcinoma of the breast that is strongly positive for estrogen receptor: a case report and literature review

Lipid-rich carcinoma (LRC) of the breast is a rare breast cancer variant that accounts for <1% of all breast malignancies. It has been reported that LRCs are negative for estrogen receptor. Here, we report a case of LRC of the breast that was strongly positive for estrogen receptor and treated with endocrine adjuvant therapy. A 52-year-old postmenopausal female noticed a lump in her right breast by self-examination and presented to our hospital. Physical examination revealed an elastic 30 mm ×20 mm hard mass in the upper medial part of her right breast. The findings obtained using ultrasonography, mammography, and contrast-enhanced magnetic resonance imaging suggested breast cancer. Core needle biopsy resulted in the diagnosis of invasive carcinoma. The patient underwent mastectomy and sentinel lymph node biopsy. Histopathologically, the tumor cells were abundant in foamy cytoplasm. Because the presence of marked cytoplasmic lipid droplets was confirmed by Sudan IV staining and electron microscopic examination of the tumor and the lipid droplets were negative for periodic acid-Schiff staining, the tumor was diagnosed as an LRC. Immunohistochemically, estrogen and progesterone receptors of the tumor were strongly positive, human epidermal growth factor receptor type 2 was negative, and the ratio of Ki-67-positive cells was ~30%. After surgery, the patient underwent combination chemotherapy with anthracycline, cyclophosphamide, and 5-fluorouracil, followed by docetaxel. Thereafter, the pateint was treated with letrozole and has remained well for 24 months with no signs of recurrence.

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.

Intraductal lipid-rich carcinoma of the breast with a component of glycogen-rich carcinoma

We report a rare case of intraductal lipid-rich carcinoma of the breast with a component of glycogen-rich carcinoma. An impalpable tumor that was revealed by mammography and magnetic resonance imaging was excised. Histologic examination showed vacuolated neoplastic cells in the mammary ducts, and electron microscopy confirmed lipid droplets in the cytoplasm. The coexistence of glycogen-rich carcinoma was shown. Lipid-rich carcinoma that is coexistent with glycogen-rich carcinoma is rare, and most lipid-rich carcinomas are invasive. Intraductal lipid-rich carcinoma is difficult to detect without echography or mammography.

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.

A non-invasive form of lipid-secreting carcinoma of the breast

Lipid-secreting carcinoma is a rare variant of breast carcinoma. The tumor cells possess abundant vacuolated cytoplasm containing neutral fat. A 68-year-old Japanese female patient presented with a left breast tumor, which was detected by mass screening, and she was admitted to our hospital. The physical examination revealed an elastic hard lump in the left lateral quadrant of the left breast. The tumor size was 1.2 × 1.0 cm in diameter and the borderline was unclear. There were no palpable axillary lymph nodes or supraclavicular nodes. Mammography showed a polygonal mass with microcalcification. Ultrasonography indicated a hypoechoic lesion measuring 9 × 4 mm in diameter, with an irregularly shaped, slightly indistinct surface. The internal echoic level of the mass was heterogenous. Enhanced magnetic resonance imaging revealed a mass of high intensity in the left breast, and the connection of the intraductal spread was not detected. The time-intensity curve showed a peak-and-plateau pattern. Fine-needle aspiration cytology suggested a malignant tumor. The patient underwent a partial resection of the left breast (breast-conserving therapy) and a left axillary lymphadenectomy. Macroscopically, the resected specimen revealed a white tumor measuring approximately 0.6 × 0.5 cm. Histopathologically, the tumor measured up to approximately 0.9 × 0.7 cm because of additional components of intraductal spread and therefore was diagnosed as an extensive ductal carcinoma in situ with focal mass formation; the tumor also had abundant foamy cytoplasm. Oil-red-O staining confirmed the presence of marked cytoplasmic lipid droplets. These droplets were periodic acid-Schiff (PAS) negative even after diastase digestion, and negative with PAS-Alcian blue staining. In immunohistochemistry, these carcinoma cells were positive for E-cadherin. Thus, the pathological diagnosis was a non-invasive form of lipid-secreting carcinoma. The tumors were negative for both estrogen receptors and progesterone receptors. There were no metastases in the left axillary lymph nodes. The patient has remained well for 8 years without any evidence of recurrence.

Histopathological and Immunohistochemical Characteristics of Two Canine Lipid-Rich Mammary Carcinomas

Clinicopathological and immunohistochemical findings of two uncommon canine lipid-rich mammary carcinomas are described. The predominant histological feature in both tumours was the presence of at least 80% of cells with intracytoplasmic vacuoles which stained positively with Sudan IV but not with alcian-blue periodic acid-schiff method. In both tumours, small groups of non-vacuolated cells were identified among the vacuolated cells. However, histological and immunohistochemical differences were also found between these tumours. Thus, one of them was composed of tumour cells with a large and single vacuole, which were arranged in lobular pattern, while the other neoplasm showed an intraductal growth of tumour cells with a fine vacuolated cytoplasm. Immunohistochemically, in the first tumour most vacuolated cells were positive for CK (cytokeratin)8-7, indicating a secretory epithelial immunophenotype while CK5 and CK8-7-expressing non-vacuolated cells were associated with luminal duct immunophenotype. However, in the second tumour the expression of CK14 in most of vacuolated cells and alpha-smooth muscle actin (alpha-SMA) in non-vacuolated cells, alone or in combination with CK5 suggested a myoepithelial immunophenotype for both cell types. These results suggest heterogeneity of the cell type and growth pattern for this type of canine tumour as has been described in women but not in dogs.

Lipid-rich carcinomas of the mammary gland in seven dogs: clinicopathologic and immunohistochemical features

Lipid-rich carcinomas occurred in seven female dogs. Affected dogs were purebred (all but one), intact (all but one), and between 4 and 13 years of age. Five of them had a history of parity, one had pseudopregnancy, and none had received contraceptive steroids. The tumors were single (five cases) or multiple (two cases) well-circumscribed masses of different sizes (varying from 1 to 6 cm in diameter), composed of solid nests and cords of tumor cells separated by a moderate amount of stroma. The tumor cells contained either multiple and small or large and solitary vacuoles that pushed the nucleus to the periphery of the cell (signet-ring cell). A glandular epithelial immunophenotype (cytokeratins 5 and 8 and 8 and 18) was observed in the majority of tumor cells. All tumors lacked both estrogen and progesterone receptors, and five out of seven tumors gave rise to local recurrence and proximal or distant metastases or both.