Apocrine metaplasia in cystic hyperplastic mastopathy. Histochemical and ultrastructural observations

TRPS1 Is Consistently Expressed in Hidradenoma Papilliferum

TRPS1 is a novel immunohistochemical marker, so far quite specific and sensitive for breast cancer and especially useful for the diagnosis of triple-negative breast cancer. TRPS1 expression has recently been reported in normal skin appendages, as well as in a variety of benign and malignant cutaneous tumors, including adnexal tumors. However, it has not yet been reported in hidradenoma papilliferum (papillary hidradenoma), a benign adnexal neoplasm, accepted to originate from mammary-like glands in the vulvar or anogenital region of middle-aged women. We report consistent nuclear expression of TRPS1 in the epithelium of 9/9 cases of hidradenoma papilliferum, while in 2/2 cases with foci of oxyphilic metaplasia, these foci were consistently negative for TRPS1 immunohistochemistry. Our findings are in line with the theory that hidradenoma papilliferum is derived from mammary-like glands and showed that TRPS1 can be an additional sensitive immunohistochemical marker for hidradenoma papilliferum.

Core needle biopsy of benign, borderline and in-situ problematic lesions of the breast: Diagnosis, differential diagnosis and immunohistochemistry

Core needle biopsy (CNB) is the most common sampling technique for the histologic evaluation of breast abnormalities. Diagnosing benign proliferative, borderline and some in-situ lesions in CNB is challenging and subject to a significant degree of interobserver variability. In addition, due to the inherent limitations of CNB, "upgrading" to a more significant pathology at excision is an important consideration for some lesions. Pathologists carry a major responsibility in patient diagnosis, risk stratification and management. Familiarity with the histologic features and the clinical significance of these common and problematic lesions encountered in CNB is necessary for adequate treatment and patient follow-up. This review will focus on benign, atypical and in-situ epithelial proliferations, papillary lesions, radial sclerosing lesions, adenosis and cellular fibroepithelial lesions. Highlights of histologic features, useful strategies for accurate diagnosis, basic immunohistochemistry and management will be presented.

Atypical Apocrine Adenosis: Diagnostic Challenges and Pitfalls

Apocrine change in the breast is an extremely common finding. In most cases, the benign or malignant nature of the lesion is easily recognized. Apocrine adenosis is used to describe sclerosing adenosis with apocrine change. The term apocrine atypia is used when there is significant cytologic atypia in apocrine cells, characterized by a 3-fold nuclear enlargement, prominent/multiple nucleoli, and hyperchromasia. Atypical apocrine adenosis is diagnosed when apocrine adenosis and apocrine atypia are superimposed. However, there are no definite criteria to distinguish atypical apocrine adenosis from apocrine ductal carcinoma in situ. Immunohistochemical markers can be confounding and may lead to erroneous diagnoses. Atypical apocrine features in sclerosing lesions may be misinterpreted as invasive carcinoma if the underlying lesion is not recognized. In the absence of definite features of malignancy, the diagnosis of apocrine ductal carcinoma in situ may be extremely difficult. In the present article, we review atypical apocrine adenosis focusing on diagnostic challenges and their implications on clinical management.

Hidradenoma Papilliferum with Oxyphilic Metaplasia

Reported here are 18 cases of hidradenoma papilliferum with oxyphilic metaplasia. All patients were women ranging in age from 29 to 74 years. Each presented clinically with a small, solitary tumor in the anogenital region. Microscopically, in addition to classic histopathological features, in every case there was oxyphilic metaplasia of the constituent epithelial cells. This finding could be likened to apocrine metaplasia, a term used in breast pathology. Other histopathological findings observed in this series, analogous to benign breast disease, included sclerosing adenosis-like changes, atypical apocrine adenosis-like changes, changes corresponding to usual ductal epithelial hyperplasia, epitheliomatosis with a streaming growth pattern, lamprocyte-like changes, clear cell change of the myoepithelium, foamy histiocyte reaction, and stromal fibrosis. Immunohistochemistry inferred that in the majority of cases oxyphilic metaplasia resulted from more lysosomes, whereas numerous mitochondria were detected in only 3 cases. Using 2 different PCR methods we identified HPV in 4 of 15 cases of hidradenoma with oxyphilic metaplasia. In addition, HPV was detected in 3 of 16 conventional papillary hidradenomas used as a control group. The following HPV types were identified: 16, 31, 33, 53, and 56. The last type was found in 5 cases. More than one HPV type from a single lesion was seen in 5 cases. Our observations are consistent with previous publications noting similarities between tumors of the breast and sweat glands. Oxyphilic metaplasia, areas with solid growth, and changes simulating atypical apocrine adenosis are rare and poorly recognized in hidradenoma papilliferum and may cause diagnostic difficulties; in our cases several submitting pathologists suspected malignancy. A causal role for HPV in hidradenoma papilliferum cannot be confirmed from our results, as the detection rate is too low. The exact role of the HPV in etiology and pathogenesis of this neoplasm has yet to be determined.

Expression of the cell death genes BNip3 and NIX in ductal carcinoma in situ of the breast; correlation of BNip3 levels with necrosis and grade

Ductal carcinoma in situ (DCIS) of the breast is an early, non-invasive lesion and the prognosis is associated with the extent of necrosis and cell death within the tumour. Two cell death genes, BNip3 and NIX, are up-regulated in response to hypoxia in breast carcinoma cells, although any involvement of either gene in disease progression is currently unknown. This study has analysed the expression of BNip3 and NIX in 56 samples of breast DCIS, as well as in adjacent benign and invasive breast tissue. Both genes are strongly expressed in the epithelial component of a subset of DCIS and invasive disease. The data show a correlation between high expression of BNip3 in the DCIS cells and a high-grade, necrotic lesion that is likely to be associated with invasive tumour. BNip3 was present in tumour-associated macrophages and in apocrine metaplastic lesions. Expression of NIX did not correlate with any of the parameters investigated.

The histologic spectrum of apocrine lesions of the breast

New data on apocrine carcinoma of the breast, especially on its unusual pathogenesis, are the facts that justify this study. The aim of this study was to describe the morphological features in both benign apocrine lesions and invasive apocrine carcinomas of the breast. The following apocrine lesions were pointed out: cysts, metaplasia, adenosis, adenoma, borderline malignant lesion, intraductal carcinoma and invasive apocrine carcinoma. Surgical specimens of breast benign and malignant lesions were fixed in formalin, embedded in paraffin blocks and the slides were stained with HE, PAS and immuno- histochemical ABC complex methods, using primary antibodies against: p53, Ki-67, androgen receptor, and GCDFP-15. The criteria of apocrine lesions, as well as classification of apocrine carcinoma were pointed out also. In the discussion we cited literature data about incidence of apocrine lesions in the breast, immunohistochemical, ultrastructural and molecular characteristics of apocrine lesions focusing on differential diagnostic problems between apocrine and nonapocrine lesions, and benign versus malignant apocrine lesion. The authors have suggested that apocrine carcinoma represents unusual type of the breast carcinoma and which may origin from the following precancerous lesions: apocrine hyperplasia, apocrine adenosis, atypical apocrine adenosis and adenoma. Immunohistochemical markers for apocrine differentiation are: GCDFP-15 and androgen receptors. Ki-67 and p53 may be good markers for differentiation between benign and malignant breast apocrine lesions. Positively staining for androgen receptors, not only in apocrine carcinoma of the breast, but also in benign lesions, has led some authors to postulate a possible role of androgens in the stimulation of breast epithelium and the development of apocrine cells and apocrine carcinomas. However, in this stage the clinical significance remains uncertain and follow-up studies will be required to evaluate this issue.

Molecular cytogenetic comparison of apocrine hyperplasia and apocrine carcinoma of the breast

The relationship of apocrine metaplasia to invasive breast cancer is controversial. Different authors have reported that apocrine differentiation in proliferative lesions may be a risk factor, a precursor lesion, or have no association with malignancy. The aim of this study was to compare the genetic alterations in benign apocrine hyperplasia with apocrine ductal carcinoma in situ (DCIS) and invasive apocrine carcinomas of the breast using comparative genomic hybridization. The mean number of alterations in apocrine hyperplasia was 4.1 (n = 10) compared to 10.2 in apocrine DCIS (n = 10) and 14.8 (n = 4) in invasive carcinoma. The most common alterations in apocrine hyperplasia were gains of 2q, 13q, and 1p and losses of 1p, 17q, 22q, 2p, 10q, and 16q. Apocrine DCIS and invasive carcinomas showed gains of 1q, 2q, 1p, and losses of 1p, 22q, 17q, 12q, and 16q as their most common DNA copy number changes. Apocrine hyperplasia is considered to be a benign lesion and its relationship to invasive carcinoma remains unclear. Our data suggest that some apocrine hyperplasias may be clonal proliferations. The mean number of alterations are lower in apocrine hyperplasia, however the changes show considerable overlap with those identified in in situ and invasive apocrine carcinoma. These alterations are also commonly seen in nonapocrine breast cancer. The data are consistent with apocrine hyperplasia as a putative nonobligate precursor of apocrine carcinoma.

Value of gross cystic disease fluid protein-15 in distinguishing metastatic breast carcinomas among poorly differentiated neoplasms involving the ovary

Women with breast cancer have an increased risk of developing primary ovarian tumors. Because a differential diagnosis between primary and metastatic tumors may be difficult in poorly differentiated ovarian neoplasms, breast carcinoma markers may be helpful in establishing the primary site of origin. Gross cystic disease fluid protein-15 (GCDFP-15), a well-known marker of apocrine differentiation, has been reported as a highly specific and sensitive breast carcinoma marker. To evaluate the usefulness of GCDFP-15 as a marker for metastatic breast cancer, we have studied, by the avidin-biotin-peroxidase technique, 14 cases of breast cancer metastatic to the ovary and compared them with 32 primary ovarian tumors and seven cases of ovarian metastases other than breast in origin. Two cases of primary ovarian cancer metastatic to the breast were also included. A strong cytoplasmic immunostaining was found in 10 of 14 cases (71%) of ovarian metastasis from breast carcinoma, and in most cases a characteristic paranuclear staining was noted. All primary ovarian tumors were negative. Ovarian metastases from tumors other than breast and both cases of ovarian carcinoma metastatic to the breast were negative. These results are highly significant (P less than .00001) and demonstrate the value of GCDFP-15 in establishing a primary breast origin among neoplasms of unknown origin involving the ovaries.

Breast macrocysts

Clinical macrocysts occur in about 7% of adult women. Modern terminology and understanding of benign breast disorders considers microcysts and macrocysts as specific clinical and pathological entities. The terminology and concepts of fibrocystic disease and its many alternative terms have been discarded. Cysts arise as an aberration of normal lobular involution (ANDI) associated with active secretion of apocrine epithelium under hormonal stimulation. They are readily managed in most cases by aspiration alone. Multiple recurrent cysts may constitute a considerable nuisance and justify short-term therapy with danazol. There is increasing evidence that multiple recurrent cysts are associated with a small, but significant increase in breast cancer risk.

The significance of atypical apocrine cells in fine-needle aspirates of the breast

Apocrine metaplastic cells are frequently present in fine-needle aspirates (FNAs) of breast lesions, especially fibrocystic disease. Occasionally, apocrine cells may be atypical and present diagnostic difficulties. The morphologic features of six breast FNAs that contained atypical apocrine cells in breast aspirates. In the six abnormal cases, the large, pleomorphic, atypical apocrine cells were the predominant cell type and occurred singly and in syncytial tissue fragments. The cells had large, eccentric, vesicular nuclei and usually multiple macronucleoli. The histologic diagnoses in the cases were apocrine carcinoma (five cases) and atypical apocrine metaplasia (one case). In comparison, benign apocrine cells are relatively small and uniform and arranged in cohesive, orderly sheets. It is concluded that, in breast FNAs, the predominance of atypical apocrine cells, occurring singly and in syncytia, should raise the suspicion of carcinoma.

Expression of GCDFP-15 in breast carcinomas. Relationship to pathologic and clinical factors

A retrospective immunoperoxidase staining study for a glycoprotein isolated from human breast gross cystic disease fluid (GCDFP-15) in 562 primary breast carcinomas in 539 patients was conducted to correlate its immunohistochemistry with pathologic and clinical factors. Overall, 55% of the carcinomas studied stained positively for GCDFP-15. In certain histologic subtypes, the percentage of carcinomas that stained positively was greater: those subtypes with apocrine histologic features (75%), intraductal carcinoma (70%), and infiltrating lobular carcinoma with signet-ring cell differentiation (90%). In contrast, only 5% of medullary carcinomas exhibited positive staining. Only 23% of breast carcinomas without apocrine features stained positively for GCDFP-15. Carcinomas that stained positively were more likely to have involved axillary lymph nodes (P less than 0.054). The staining was independent of nuclear grade, mitotic index, tumor size, and estrogen receptor status. Positive staining was related to a history of gross cystic disease but not to age, parity, menopausal status, or age at first birth. A positive stain was not related to risk of recurrence or survival.

Apocrine carcinoma of the breast--a case report

A case of apocrine carcinoma of the breast is reported herein. Apocrine carcinoma is a rare tumor characteristically composed of large cells with eosinophilic cytoplasm. This case involves a 34-year old woman who underwent a modified radical mastectomy and is now doing well with no evidence of recurrence, 10 months after her surgery.

Invasive apocrine carcinoma of the breast: a long term follow-up study of 34 cases

We have reviewed the morpho-functional criteria for infiltrating apocrine carcinomas of the breast and analysed long term follow-up of this entity. Thirty-four cases of pure apocrine carcinomas were retrieved from the files of the Dept. of Pathology, IGR, France, for the years 1955-1982. Each case was matched with two controls of other infiltrating ductal carcinomas according to the most important prognostic parameters: nodal status, histograde, anatomic tumor size, and patient age. No significant difference between the survival curves of the two groups was seen. Apocrine carcinoma, although possessing peculiar morphological, ultrastructural, biochemical, and immunohistochemical features to merit recognition as a separate histologic variant of breast cancer, by itself has no apparent clinical significance.

Fine-needle aspiration of an apocrine breast carcinoma with multivacuolated, lipid-rich, giant cells

The frequency of mammary apocrine carcinoma varies considerably and reflects the definitional differences of various researchers. Lipid synthesis by malignant mammary cells is not uncommon, and occasionally it is so extensive that the designation lipid-rich carcinoma is warranted. Many subtypes of lipid-rich carcinoma are described. Although focal apocrine change is observed in one type, a tumor composed predominantly of an apocrine carcinoma with an intimate admixture of lipid-rich malignant cells is previously undescribed. The fine-needle aspiration, histologic, and ultrastructural features of such a tumor is delineated for which the descriptive title lipid-rich apocrine carcinoma is coined.

Early apocrine change in hyperplastic cystic disease

Biopsy material from 42 cases of florid hyperplastic cystic disease of the breast were reviewed and were found to have foci of apocrine metaplasia. This appearance was limited to the ductular epithelium of hyperplastic lobules. It is believed that this scattered change is an initial feature in relation to the genesis of apocrine-lined and fully developed cysts.

Apocrine differentiation in human mammary carcinoma

Six invasive carcinomas that contained apocrine differentiation as the primary morphologic pattern were selected from a series of 1500 prospectively examined breast carcinomas (0.4%). While apocrine features were seen in many breast tumors, these six cases were identified by uniformly fine granular, pale, eosinophilic cytoplasm with apical cytoplasmic projections similar to that seen in apocrine metaplasia. In each example, ultrastructural analysis revealed the presence of numerous 400-600 nm membrane bound vesicles with dense homogeneous osmophilic cores. These granules clustered toward the apex of the cytoplasm in the majority of the epithelial cells. All six tumors were deficient in high-affinity, low-capacity 8S estrogen and progesterone proteins, while a high-capacity, low-affinity, nonsaturable 4S progesterone-estrogen binding protein was observed. Cortisol did not bind to this protein. These observations characterize the ultrastructure of apocrine carcinoma as a variant of human mammary carcinoma.

Ultrastructural analysis of apocrine carcinoma of the human breast

A case report with ultrastructural analysis of an apocrine carcinoma of the breast is presented. The key finding with electron microscopy is numerous large mitochondria with abundant incomplete cristae. The ultrastructure of this tumor is compared to the ultrastructure of apocrine cells in the skin, oncocytes, and apocrine metaplastic cells of the breast. The apocrine carcinoma cells have some of the features of typical metaplastic breast epithelium and some features of oncocytes. Their exact origin remains open to speculation.

The ultrastructure of tubular carcinoma of the breast

The ultrastructure of four tubular carcinomas of the breast is described. The neoplastic tubules are single layered and lack a myo-epithelial component, an important feature in distinguishing tubular carcinoma from sclerosing adenosis. Numerous myo-fibroblasts are present in the stroma of all four tumours and, since cells of this type have been recorded only occasionally in the stroma of other types of breast carcinoma, it is suggested that they may be a characteristic feature of tubular carcinomas.