Immunohistochemical Characterization of a Large Cohort of Triple Negative Breast Cancer

Introduction. Triple negative breast carcinomas are characterized by a lack of hormone receptor and HER2 expression and inconsistent expression of breast-specific immunohistochemical markers. The expression of many site-specific markers in these tumors is largely unknown. The objective of the study was to examine the expression of widely used immunohistochemical markers on a large cohort of triple negative breast cancer. Methods. Sections from tissue microarrays were stained with 47 markers using routine protocols. Most markers were scored using a modified Allred method. ATRX, BAP1, SMAD4, e-cadherin, and beta-catenin were scored as retained or lost. Mammaglobin was considered positive if there was at least moderate intensity staining in any tumor cells. P16 was scored as overexpressed or not overexpressed; p53 was scored as wildtype, overexpressed, null, or cytoplasmic. Results. The cohort consisted of 639 tumors including 601 primary and 32 metastases. Overall, 96% expressed GATA3, mammaglobin, and/or SOX10 while 97% of no special type tumors expressed this panel. Carcinoma of apocrine differentiation demonstrated an AR positive, SOX10 negative, K5 negative/focal immunophenotype. PAX8 (SP348), WT1, Napsin A, and TTF1 (8G7G3/1) were never or rarely expressed while CA9, CDX2, NKX3.1, SATB2 (SATBA410), synaptophysin, and vimentin were variably expressed. Conclusions. Almost all TNBC express at least 1 of the 3 IHC markers: GATA3, mammaglobin, and/or SOX10. Carcinoma of apocrine differentiation is characterized by an AR positive, SOX10 negative, K5 negative or focal immunophenotype. Cautious interpretation of so-called site-specific markers, with knowledge of antibody clones, is required in excluding the diagnosis of triple negative breast cancer.

Case Report: A challenging diagnosis of an apocrine sweat gland carcinoma

The differential diagnosis for an axillary mass in a patient with a previously treated malignancy is broad and definitive tissue diagnosis is required to guide treatment and surveillance strategies. We present the case of a 76-year-old African American male with a history of prostate cancer who presented with a left axillary mass two years after achieving remission from his prostate malignancy. Due to the diagnostic challenge, this excisional biopsy was reviewed at four different academic centers. Although no universal consensus among these institutions' pathologists, but in the context of clinical presentation and anatomic location, the overall clinical findings are consistent with apocrine sweat gland carcinoma. The mass was treated with complete local surgical excision, though regional lymph node metastasis occurred 2 years later. Multimodal treatment with surgery and radiation was done with removal of regional metastasis and no distant disease was identified. Primary apocrine carcinoma is a rare cutaneous neoplasm with less than 100 reported cases in the literature. A combination of clinical history and presentation, histomorphology, anatomical location, and immunohistochemistry is used to support the diagnosis and ultimately drive management.

Apocrine adenocarcinoma of the breast: A rare special subtype with divergent theranostic markers

Carcinoma of the breast with apocrine differentiation also known as apocrine adenocarcinomas is special histological subtypes comprising approximately 1% of breast cancers. They are estrogen receptor/progesterone receptor-negative and androgen receptor-positive tumors having more than 90% population of tumor cells with apocrine morphology. We present a 49-year-old woman with a breast lump in the right upper outer quadrant clinically and radiologically diagnosed as malignancy and histologically proven as apocrine adenocarcinoma of the breast owing to the morphology comprising tumor cells having abundant granular cytoplasm, central to the eccentric nucleus and prominent nucleoli. On immunohistochemistry, it was a triple-negative tumor with AR positivity. As apocrine adenocarcinoma of the breast has an uncertain prognosis, variable HER2/neu overexpression, debatable responses to neoadjuvant therapy, and probable response to androgen therapy, the onus of diagnosing and reporting these tumors accurately lies with the pathologist. Moreover, as the presentation of these tumors is similar to invasive breast carcinoma, no special type but with potentially different and useful theranostic markers, an emphasis on specifying this histological subtype is becoming increasingly essential.

Gross Cystic Disease Fluid Protein-15 (GCDFP-15) Expression Characterizes Breast Mucinous Carcinomas in Older Women

The predominant histological subtype of breast mucinous carcinoma in older women is type B (hypercellular type), and, in younger women, it is type A (hypocellular type). The characteristics of mucinous carcinomas of the same histological subtype may differ between older and younger women. This study aims to systematically clarify the pathological/immunohistochemical features of mucinous carcinomas. A total of 21 surgical cases of mucinous carcinoma (type A/B: 9/12 cases) in the older group (≥65 years) and 16 cases (type A/B: 14/2 cases) in the younger group (≤55 years) (n = 37) were included. Gross cystic disease fluid protein-15 (GCDFP-15) and eight other markers were used for immunostaining. The GCDFP-15-positive rate in the older group was high regardless of the histological subtype (type A, 77.8%; type B, 91.7%). The GCDFP-15 positivity in the older group was significantly higher than that in the younger group (p < 0.001 for Allred score). Among type A, GCDFP-15 positivity was significantly higher in the older group than in the younger group (p = 0.042 for the Allred score and p = 0.007 for the positivity rate). The present results suggest that GCDFP-15 expression characterizes mucinous carcinomas in older women.

Dermoscopy of cutaneous adnexal tumors: a systematic review of the literature

Cutaneous adnexal tumors (ATs) encompass a variegated group of hamartomas and benign or malignant tumors, originating from the hair follicle, sebaceous, eccrine or apocrine glands that may simulate other cutaneous neoplasms. This study aims to provide a comprehensive overview of the spectrum of clinical and dermoscopic features of ATs, to better define these lesions and assist in differential diagnosis. We performed a two-step systematic search of literature in PubMed, Embase, and Cochrane Library databases from inception until September 4, 2020. In the first step we aimed to define histological variants of ATs with descriptions of dermoscopic criteria. The second step included a search for the name of each previously identified AT variants in the same databases adding "AND (epilum* or dermosc* or dermatosc*)". All study types in English-language reporting dermoscopic images of ATs were included. Collisions between ATs and other inflammatory or neoplastic skin lesions were excluded, with the exception of collisions with a sebaceous nevus. The protocol of this study was prospectively registered in PROSPERO (CRD42021244677). In total, 206 articles met our inclusion criteria, encompassing 372 ATs in 365 patients. Most ATs were apocrine-eccrine (n=217, 58.3%, n=173 benign) with a prevalence of poromas (n=82), followed by follicular ATs (n=88, 23.7%, n=83 benign) and sebaceous ATs (n=67, 18.0%, n=49 benign). Most patients had a single AT lesion (320, 86.0%), while 42 (11.3%) had multiple ATs. A syndrome causing multiple ATs was identified in 15 patients. Histopathological analysis revealed 82% benign (n= 305) and 18.0% malignant (n=67). ATs were classified according to their ability to mimic 4 groups of more common skin tumors: basal cell carcinoma, squamous cell carcinoma, melanocytic lesions and benign cutaneous lesions. Moreover, we have highlighted the ability of malignant variants of ATs to simulate benign skin lesions. This systematic review offers a comprehensive overview of the common clinical and dermoscopic features of follicular, sebaceous and apocrine-eccrine ATs and details possible differential dermoscopic features.

Primary cutaneous apocrine carcinoma of the scalp: Two case reports and literature review

RATIONALE

Apocrine carcinoma is a rare malignant sweat gland tumor that has been reported in approximately 200 cases. This tumor usually occurs in the axilla, but in rare cases, it can also develop in the scalp. In the present work, we report 2 cases of cutaneous apocrine carcinoma of the scalp.

PATIENT CONCERNS

Two men visited our outpatient clinic with recurrence of tumor after undergoing surgery for scalp tumor at another hospital.

DIAGNOSES

Brain magnetic resonance imaging of a 56-year old man showed the presence of a 5.0 × 4.5 × 4.4 cm scalp mass in the right parietal region, invading the skull and dura mater and a 2.2 × 2.0 × 0.7 cm bony mass without any skin lesions right next to the scalp mass. Neck magnetic resonance imaging of a 76-year-old man revealed the presence of a well-defined oval mass in the subcutaneous layer of the left occipital scalp and 2 enlarged lymph nodes in the left neck. Definite diagnoses were made postoperatively. The patients were diagnosed with cutaneous apocrine carcinoma. The diagnosis was confirmed through histopathological and immunohistochemical staining tests.

INTERVENTIONS

The tumors were removed with a wide safety margin and reconstructive surgery was performed.

OUTCOMES

Additional radiotherapy or chemotherapy was performed. Follow-up more than 6 months revealed no recurrence or metastasis.

LESSONS

If accurate diagnosis and treatment had taken place at the initial stages of the primary cutaneous apocrine carcinoma, it would have been possible to prevent recurrence and intracranial invasion. As recurrent primary cutaneous apocrine carcinoma can become aggressive and difficult to treat, even a small mass on the scalp must be evaluated carefully and treated properly.

Pigmented apocrine hamartoma: A distinct and uncommon pigmented lesion with dendritic melanocytes and appraisal of terminology

A 20-year-old female presented to a gynecologist with an irregular, darkly pigmented, vulvar lesion. Histopathologic sections of a biopsy specimen showed cystically dilated glands with apical snouts, pigmented secretion, and numerous dendritic melanocytes. The lesion was diagnosed as a pigmented apocrine hamartoma of the vulva. We report the fifth case of this uncommonly encountered entity and discuss the conflicting terminology in the literature of this rare, pigmented lesion.

Benign cyst of the male breast. An exceedingly rare entity that may pose a diagnostic dilemma. Management and literature review

Cysts represent the most common cause of a breast mass in women. On the contrary, in men, the presence of a benign apocrine cyst is an exceedingly rare occurrence, with only a few cases reported in the literature. We describe herein a case of benign apocrine breast cyst without concurrent gynecomastia in a 41-year-old male. Diagnostic evaluation and management are discussed, along with a review of the literature. Given the extreme rarity of benign breast cysts in males, a thorough investigation is essential in male patients presenting with cystic breast lesions. Diagnostic breast imaging may be challenging. Surgical resection of the cyst should be considered in the presence of atypical imaging features to exclude underlying malignancy.

Signet-ring cell/histiocytoid carcinoma of the axilla: a clinicopathological and genetic analysis of 11 cases, review of the literature, and comparison with potentially related tumours

AIMS

The aim of this study was to determine the clinicopathological and genetic characteristics of axillary signet-ring cell/histiocytoid carcinoma (SRCHC) and the relationship between axillary SRCHC, eyelid SRCHC, and conventional apocrine carcinoma (AC).

METHODS AND RESULTS

Eleven cases of axillary SRCHC, four cases of eyelid SRCHC, eight cases of axillary AC and five cases of invasive lobular carcinoma (ILC) were retrieved. Additionally, 14 axillary and 43 eyelid SRCHC cases from the literature were reviewed. Male predominance was prominent for axillary SRCHC (24:1) and eyelid SRCHC (42:5). Axillary SRCHC formed a circumscribed plaque or nodule, unlike eyelid SRCHC. Lymph node metastasis was predominantly seen in axillary SRCHC cases (72%, 18/25), but not in eyelid SRCHC cases (19%, 9/47). Axillary SRCHC and eyelid SRCHC were histopathologically similar and showed rare tubular formations. Immunoexpression of cytokeratin 7, cytokeratin 19, mucin 1, mucin 5AC, BerEP4 and androgen receptor was seen in all tested cases of the four diseases. Oestrogen and progesterone receptors were negative in both types of SRCHC and AC, but were strongly positive in ILCs. Complete loss of E-cadherin expression was seen in approximately one-quarter of both types of SRCHC and in all ILCs. PIK3CA mutations were detected in all three sequenced cases (two axillary SRCHCs and one eyelid SRCHC).

CONCLUSION

The histopathological, immunohistochemical and genetic findings suggest that both types of SRCHC are phenotypic variants of AC, although there are differences in sex, macroscopic findings and the frequency of lymph node metastasis among the three. In contrast, ILC differs from the other three tumour types.

Current Diagnosis and Treatment Options for Cutaneous Adnexal Neoplasms with Apocrine and Eccrine Differentiation

Adnexal tumors of the skin are a rare group of benign and malignant neoplasms that exhibit morphological differentiation toward one or more of the adnexal epithelium types present in normal skin. Tumors deriving from apocrine or eccrine glands are highly heterogeneous and represent various histological entities. Macroscopic and dermatoscopic features of these tumors are unspecific; therefore, a specialized pathological examination is required to correctly diagnose patients. Limited treatment guidelines of adnexal tumor cases are available; thus, therapy is still challenging. Patients should be referred to high-volume skin cancer centers to receive an appropriate multidisciplinary treatment, affecting their outcome. The purpose of this review is to summarize currently available data on pathogenesis, diagnosis, and treatment approach for apocrine and eccrine tumors.

Apocrine ductal carcinoma in situ associated with testosterone therapy in a transgender individual

We report the first case of apocrine ductal carcinoma in situ (DCIS) in a female-to-male transgender individual on testosterone therapy (TT). The gender confirmation total mastectomy revealed 2 cm DCIS with apocrine cytology, high nuclear grade with associated calcification, and necrosis. Immunohistochemistry revealed the DCIS was negative for ER, positive for AR with HER2/neu overexpression (3+). This patient with negative screening mammography developed apocrine DCIS on TT, suggesting that gender-affirming hormone therapy may have advanced malignant transformation of atypical apocrine cells. This may have implications for increased surveillance within the transgender population.

Ectopic Hidradenitis Suppurativa: Case Report and Review of Literature

Hidradenitis suppurativa is a chronic, recurrent follicular-based inflammatory condition classically occurring in apocrine-rich areas; commonly affected areas include the anogenital, axillary, inframammary, and inguinal regions. Infrequently, hidradenitis suppurativa can occur in locations where apocrine glands are scant or absent; in this setting, it has been referred to as ectopic hidradenitis suppurativa. The case of a 59-year-old man with ectopic hidradenitis suppurativa on his right posterior thigh is described. The postulated pathogenesis, treatment modalities, and various reported locations of ectopic hidradenitis suppurativa are reviewed.

Mixed Invasive Apocrine Papillary/Micropapillary Carcinoma of the Breast: Another Brick in the Triple-Negative Wall

Pure invasive papillary carcinoma (IPC) is a rare subtype of breast carcinoma with good prognosis compared with classical invasive breast carcinoma (IBC) of no special type. The majority of IPC are estrogen receptor and progesterone receptor (ER/PR) positive and HER2 negative (luminal A-like). We report the case of a 72-year-old women who was referred to the Senology Clinic for a routine workup following surgery for an intraductal papilloma. The core needle biopsy (CNB) showed a lesion mainly composed of irregular papillae and micropapillae with apocrine epithelial cells of low-to-intermediate nuclear grade, without a myoepithelial cell layer within the papillae and at the periphery, as demonstrated with multiple immunostains. The diagnosis of apocrine papillary lesion of uncertain malignant potential was made. The subsequent lumpectomy showed an IBC with the same cyto-architectural features as the CNB. In addition, lymphovascular invasion and papillary/micropapillary apocrine in situ lesion were noted. Notably, the tumor was ER/PR and HER2 negative and strongly positive for androgen receptor. A final diagnosis of mixed apocrine papillary/micropapillary carcinoma with triple-negative status was made. To the best of our knowledge, this is the first report of an IBC with these features. Breast pathologists should be aware of this entity when dealing with CNB samples characterized by a complex papillary lesion with apocrine atypia that lacks a myoepithelial cell layer on multiple immunostains. These lesions should be classified at least as of uncertain malignant potential based on the cyto-architectural features prompting a surgery for removal.

Cutaneous spindle cell adenolipoma with eccrine and apocrine differentiation

Cutaneous spindle cell adenolipoma (SCAL) is a recently described rare variant of lipoma with 11 cases reported to date. Here we report a consultation case of a 77-year-old male who presented with a nodule on the right nasolabial fold, diagnosed as apocrine fibroadenoma or sebaceous hyperplasia by an outside pathologist. The specimen revealed an ill-defined dermal tumor composed of mature adipocytes, bland spindle cells, ropey collagen, and dilated eccrine and apocrine glands and ducts in a fibromyxoid stroma. The spindle cells were positive for CD34 and negative for S100 protein and SOX10. These findings are consistent with those of cutaneous SCAL. The pathogenesis of this entity is controversial and includes a hamartomatous process, derivation from adipose tissue surrounding eccrine glands, or preexisting glands entrapment within a growing lipoma. In the present case, the glandular component is extensive and includes both eccrine and apocrine differentiation, which has not been previously described and further supports the hamartomatous nature. Awareness of this rare entity is helpful to prevent confusion with other look-alike primary and metastatic cutaneous lesions.

Polarizable crystals in apocrine sweat gland tumors: A series of 3 cases

Polarizable calcium oxalate (CaOx) crystals have been well documented in breast biopsies, generally associated with benign apocrine metaplasia. In contrast, polarizable crystals are only rarely reported in skin adnexal neoplasms. We report 3 different cases of sweat gland tumors with polarizable crystals morphologically suggestive of CaOx: 1 apocrine hidrocystoma and 2 tubular apocrine adenomas. The histologic features were examined in 3 cases. Clinical presentation summary included 2 males and 1 female, ages 53 to 74 years, with lesions located on the left cheek, inferior vertex scalp and the left eyebrow. All 3 cases showed polarizable, geometric, plate-like and fractured, colorless crystals within the lumens of the neoplasm. Of note, these crystals were seen only on the toluidine blue-stained section of Case #1, but were not present on the corresponding permanent section. We hypothesize that polarizable crystals may be present in sweat gland neoplasms more often than previously documented, but that they may often dissolve with routine processing, accounting for their rare visibility. We highlight this rare finding, and suggest that it may be underreported. We only noted this finding in benign apocrine tumors; further investigation would be necessary to determine whether these crystals are also seen in other cutaneous adnexal neoplasms.

Malignant Clear Cell Hidradenoma of the Breast

A 58-year-old female had a mass in the right breast palpable beneath the areola. A mammogram revealed a 1.5-centimeter soft tissue density that was confirmed with a subsequent ultrasound. The patient underwent a core needle biopsy which was initially reported as a moderately differentiated invasive ductal carcinoma. Immunohistochemical analysis revealed negative staining for estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor (HER2), mammaglobin, and gross cystic disease fluid protein 15 (GCDFP-15). A wide local excision of the mass was performed. The pathology report stated the tumor had an infiltrative growth pattern with a desmoplastic stromal response with enhanced epithelial atypia consistent with malignant transformation of a nodular clear cell hidradenoma. Clear cell hidradenoma is a very rare tumor originating from the sweat gland and has a propensity for the face and extremities. The malignant variant of this tumor is extremely rare and has been reported to originate from the breast in few cases. This case represents the difficulty in diagnosing this tumor along with the radiographic and histologic features that can distinguish this malignancy from other entities.

Aberrant Expression of Napsin A in Breast Carcinoma With Apocrine Features

An incidental finding of napsin A-positive breast carcinoma with apocrine features during workup for metastatic cancer in an axillary lymph node led to our investigation of the incidence of napsin A expression in breast carcinomas, focusing on those with apocrine features. We included 97 cases of breast carcinomas and performed immunohistochemistry with napsin A, GATA-3, thyroid transcription factor-1, and GCDFP-15. There was a statistically significant difference between apocrine and nonapocrine cases with respect to polyclonal napsin A H-scores (P < .00152), monoclonal napsin A H-scores (P < .00631), GATA-3 H-scores (P < .00029), and GCDFP-15 H-scores (P < .00251). Of the 49 cases of apocrine carcinoma, monoclonal napsin A antibody was positive in 66.7% of cases, including in 7 (14.6%) that showed 3+ staining. The majority of nonapocrine cases were negative (62.5%) or weakly (1+) positive (29.2%), with none exhibiting 3+ strength. It is important for pathologists to be aware that breast carcinomas with apocrine features can express napsin A.

Three Adult Cases of Orbital Hidrocystoma Presenting with Blepharoptosis

Purpose: To report adult cases of superior orbital apocrine hidrocystoma. Methods: Retrospective case series of three patients with superior orbital apocrine hidrocystoma and blepharoptosis with review of the clinical aspects of each of the cases. Results: All three cases presented with blepharoptosis. Two of the cases had occult hidrocystoma, and one was visibly subcutaneous at presentation. Conclusions: Although rare and more common along the eyelid margin, apocrine hidrocystomas may occur in the orbit leading to secondary blepharoptosis and should be included within the differential diagnosis of orbital cysts. Physicians should therefore be aware of this possibility.

Oncocytic and apocrine epithelial myoepithelial carcinoma: novel variants of a challenging tumor

Epithelial myoepithelial carcinoma (EMCa) is a rare but well characterized biphasic salivary gland malignancy with several variant morphologies. Oncocytic and apocrine EMCa are uncommon variants that constitute up to 8 % of all EMCa. Both variants invoke an eosinophilic or oncocytic differential diagnosis and challenge the traditional requirement of clear myoepithelial cells for EMCa. Oncocytic EMCa occurs in patients a decade older than conventional EMCa. This variant is often papillary with calcification and associated with sebaceous components and occurs in older individuals. Apocrine EMCa is named for its apocrine ductal component, which may be mistaken for salivary duct carcinoma. In this variant, the epithelial component often shows overgrowth in a cribriform or even solid pattern and is immunophenotypically defined by androgen receptor and gross cystic disease fluid protein 15 positivity. The most important aspect of differentiating both oncocytic and apocrine EMCa from other salivary oncocytic tumors is recognition of the biphasic nature of these variants and confirmation that the abluminal outer layer consists of plump, 'activated' myoepithelial cells, regardless of tinctorial characteristics. Both oncocytic and apocrine EMCa behave very indolently in the limited literature to date.

Metastatic sweat gland adenocarcinoma: A clinico-pathological dilemma

BACKGROUND: Sweat gland adenocarcinoma is a rare malignancy with high metastatic potential seen more commonly in later years of life. Scalp is the most common site of occurrence and it usually spreads to lymph nodes. Liver, lung and bones are the distant sites of metastasis with fatal results. The differentiation between apocrine and eccrine metastatic sweat gland carcinoma is often difficult. The criteria's are inadequate to be of any practical utility. CASE REPORT: Two cases of metastatic sweat gland adenocarcinoma (one of eccrine and the other one of apocrine origin) are being reported on account of the rarity and different outcome. CONCLUSION: Sweat gland carcinomas are rare cancers with a poor prognosis often presenting as histological surprises. Surgery in the form of wide local excision and lymph node dissection is the mainstay of treatment. Chemotherapy and/or radiotherapy has limited role.