Hidradenoma papilliferum with mixed histopathologic features of syringocystadenoma papilliferum and anogenital mammary-like glands: report of a case and review of the literature

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.

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.

Hidradenoma papilliferum: an unusual benign perianal tumour

Hidradenoma papilliferum is an uncommon benign tumour that is located in the anogenital region of middle-aged women. They are usually only diagnosed after excision and are thought to arise from anogenital mammary-like glands. We present the case of a young woman who noticed a slow growing perianal lump which caused minimal symptoms.

[Anogenital mammary-like glands and related lesions. Part 1. Benign tumors and tumor-like disorders]

Anogenital mammary-like glands represent a normal anatomic constituent of the anogenital area and may give rise to many benign and malignant tumors that morphologically mimic similar breast diseases. The literature review is complemented by a description of 286 cases of benign tumors and tumor-like processes in the mammary-like glands. The paper presents the clinical and morphological characteristics of papillary hidradenoma, fibroadenoma, benign phyllodes tumor, lactating adenoma, sclerosing adenosis, pseudoangiomatous stromal hyperplasia, etc.

PIK3CA and AKT1 mutations in hidradenoma papilliferum

AIMS

Hidradenoma papilliferum (HP) is a benign vulvar neoplasm that arises from anogenital mammary-like glands, and its morphology is similar to mammary intraductal papilloma. The aim of this study was to investigate oncogenic mutations involved in the tumourigenesis of HP. We focused specifically on PIK3CA and AKT1 mutations, which are both reported to be detected in 33% of mammary intraductal papillomas.

METHODS

In total, seven HP cases were analysed. Clinicopathological analyses and immunohistochemistry for oestrogen receptor, p63, smooth muscle actin (SMA), p53 and β-catenin were performed. Furthermore, PIK3CA, AKT1, BRAF and KRAS hot spot mutations were examined by Sanger sequencing.

RESULTS

Morphologically, all HPs had a papillary and tubular architecture with a biphasic pattern of epithelial and myoepithelial cells. Immunohistochemistry revealed that oestrogen receptor expression was restricted to epithelial cells, whereas p63 and SMA were exclusively expressed in myoepithelial cells. The patterns of p53 and β-catenin immunostaining suggested wild-type genotypes. Direct sequencing revealed the presence of somatic PIK3CA mutations (Ex9. c.1633G>A, p.E545K and Ex20. c.3140A>G, p.H1047R) in two of the HPs and an AKT1 (c.49G>A, p.E17K) mutation in one. BRAF and KRAS mutations were not found in any of the HP cases.

CONCLUSIONS

PIK3CA and AKT1 are frequently mutated in HP tumours (29% and 14%, respectively). PIK3CA/AKT1 pathway alterations in HP further support the hypothesis that HP is the vulvar (anogenital mammary-like gland) analogue of breast intraductal papilloma.

Hidradenoma Papilliferum: A Clinicopathologic Study of 264 Tumors From 261 Patients, With Emphasis on Mammary-Type Alterations

Hidradenoma papilliferum (HP), also known as papillary hidradenoma, is the most common benign lesion of the female anogenital area derived from anogenital mammary-like glands (AGMLG). HP can be viewed conceptually as the cutaneous counterpart of mammary intraductal papilloma. The authors have studied 264 cases of HP, detailing various changes in the tumor and adjacent AGMLG, with emphasis on mammary-type alterations. In many HP, the authors noticed changes typical for benign breast lesions, such as sclerosing adenosis-like changes, usual, and atypical ductal hyperplasia. Almost in a third of cases, remnants of AGMLG adjacent to the lesion were evident, manifesting columnar changes reminiscent of those seen in breast lesions. This study shows that the histopathological changes in HP run a broad spectrum comparable with that in the mammary counterpart and benign breast disease.

Vulval Microglandular Adenosis-like Neoplasm With Chondromyxoid Stroma: Report of a Unique Case

Microglandular adenosis of the breast is an uncommon lesion which can mimic tubular carcinoma. It is composed of small round tubules lined by a single layer of flat or cuboidal epithelial cells, often with eosinophilic colloid-like material within the lumen. The absence of a myoepithelial cell layer and preservation of basement membrane around the tubules are characteristic features. We report the first case of a vulval "neoplasm" in a 60-yr-old woman showing features identical to microglandular adenosis of the breast except for the presence of an unusual chondromyxoid stroma. This case reinforces the analogy between vulval lesions derived from anogenital mammary-like glands and breast lesions and also adds a new entity to the list of lesions arising from these glands.

A tumoriform lesion of the vulva with features of mammary-type fibrocystic disease

: Fibrocystic disease is a common benign lesion of the breast. Variably sized cysts, apocrine metaplasia, fibrosis, calcification, chronic inflammation, and epithelial hyperplasia are the basic morphological changes seen in mammary fibrocystic disease. We report a rare tumoriform lesion of the vulva with features of fibrocystic disease, which seems to be the first description of this condition in the vulva. The pertinent literature is discussed. The reported lesion further demonstrates the analogy between tumors of anogenital mammary-like glands and mammary neoplasms.

Hidradenoma papilliferum of the vulva in association with an anogenital mammary-like gland

Hidradenoma papilliferum (HP) is a benign adnexal neoplasm which preferentially develops in the anogenital region of women. Although the origin of HP was previously thought to be an apocrine sweat gland, recent studies have suggested that it may derive from the anogenital mammary-like gland (MLG). In this paper, we present a 43-year-old Japanese woman with hidradenoma papilliferum of the vulva. The lesion developed 7 years prior to her visit, and clinically appeared as a skin-colored cystic nodule. Histopathological examination revealed that the neoplasm was formed by the tubular structures consisting of two types of pleomorphic cells, columnar cells in the luminal layer and cuboidal cells in the basal layer. Further, the surgical specimen contained a wide, divergent, lobular ductal structure located in the vicinity of the neoplastic lesion, which was consistent with MLG.

Vulvar Adnexal Lesions: A 32-Year, Single-Institution Review From Massachusetts General Hospital

Context.—Because the skin and modified mucosal surfaces of the vulvar region contain dense apocrine glands and anogenital mammary-like glands, in addition to eccrine glands and folliculosebaceous units, benign as well as malignant lesions derived from these adnexal structures are, not surprisingly, found in the vulva. However, their incidence occurring in the vulva has not been reported, to our knowledge.

Objective.—To determine the incidence of various vulvar adnexal lesions.

Design.—We performed a retrospective review (1978–2010) of the cases at our institution.

Results.—A total of 189 vulvar adnexal lesions were identified. Most of these lesions were benign (133 of 189; 70%), with hidradenoma papilliferum being the most common, followed by syringoma and various types of cysts. Rare cases of tubular adenoma, poroma, spiradenoma, hidradenoma, cylindroma, sebaceoma, and trichoepithelioma were identified. Malignant adnexal neoplasms comprised the remaining 30% (56 of 189) of the cases. Extramammary Paget disease was the most common (49 of 56), and 29% (14 of 49) demonstrated an invasive component. Rare cases of basal cell carcinoma, sebaceous carcinoma, apocrine carcinoma, adenoid cystic carcinoma, and spiradenocarcinoma were identified.

Conclusions.—In this retrospective review, we identified several benign entities that have not been previously reported on the vulva, namely pilomatricoma, poroma, spiradenoma, and sebaceoma. Hidradenoma papilliferum and extramammary Paget disease were the most common benign and malignant adnexal neoplasms, respectively. The spectrum of various vulvar adnexal lesions appears to reflect the frequency of the underlying glandular elements.