A Composite Neoplastic Lesion of the Vulva With Mixed Features of Fibroadenoma and Hidradenoma Papilliferum Combined With Pseudoangiomatous Stromal Hyperplasia Containing Multinucleated Giant Cells

Fibroadenoma of the vulva with pseudoangiomatous stromal hyperplasia: A common neoplasm in uncommon site

Mammary-type tissue in the vulva was first described in 1872 but has been rarely reported in the literature. This tissue was previously considered as ectopic breast tissue that occurs as a result of incomplete regression of the milk line. Similar to native breast tissue, ectopic mammary tissue is hormone-sensitive and can develop benign changes, such as fibroadenoma, as well as malignant changes. A more recent theory suggests that these benign and malignant mammary-type entities arise from mammary-like anogenital glands, which constitute normal vulvar components. We report a case of a 41-year-old woman who presented with a chronic asymptomatic cyst on the left vulva that eventually became uncomfortable, especially on standing. The cyst was located on the labium minus, measuring 1.0 × 0.5 cm, with no identified erythema or other skin abnormalities. Excision of the lesion and subsequent microscopic examination showed a circumscribed mass with a nodular overgrowth of epithelial and stromal components, resembling a mammary fibroadenoma with pseudoangiomatous stromal hyperplasia. We bring to attention this rare diagnosis and the importance of considering it in the presence of a vulvar lesion. The malignant and recurrence potential of mammary-type tissue necessitates excision with clear margins and close monitoring of these patients.

Ectopic mammary tissue in vulva: case report and systematic literature review

Objective

To report the case of a patient diagnosed with ectopic mammary tissue in the vulva, and to conduct a literature review of the diagnosis, treatment and prognosis of this condition in that location.

Materials and Methods

A 49-year-old patient who presented with a painful vulvar mass to a private intermediate complexity center in Bogotá, Colombia. The lesion was assessed on ultrasound and then surgically excised; histopathology showed ectopic mammary tissue with absence of malignancy. A search was conducted in the PubMed, Embase, Cochrane, LILACS and Scielo databases using the keywords “Vulva,” “Breast” and “Ectopic.” Case reports and case series of women with histopathology-confirmed mammary tissue in the vulva were included.

Results

Overall, 184 titles were identified and, of these, 94 were ultimately included, for a total of 126 cases, with 57.9% being benign tumors, 95% in women under 50 years of age, and 42.06% being malignant tumors, 92% in women over 50 years of age. Diagnosis was made on the basis of the clinical findings, with ancillary diagnostic imaging, tumor markers and immunohistochemistry in some cases. Local excision was performed in 91% of cases with benign pathology and in 43% of cases with malignant pathology, with the diagnostic method being therapeutic.

Conclusions

Ectopic mammary tissue in the vulva must be considered as part of the differential diagnosis of vulvar masses, prognosis being different in pre and postmenopausal women. Further studies are needed to enhance the characterization of this condition and define the ideal course of treatment in terms of relapse and survival.

Atypical Non-neoplastic Changes in Anogenital Mammary-like Glands Accompanying Invasive Squamous Cell Carcinoma

Long regarded as ectopic or supernumerary breast tissue, anogenital mammary-like glands (AGMLG) are now considered a normal constituent of the anogenital area. AGMLG are presumed to be the origin for various benign and malignant lesions. Changes in AGMLG compatible with usual ductal hyperplasia and atypical ductal hyperplasia considered as precursor lesions and its presence in specimens can be explained by their role in the pathogenesis of primary extramammary Paget disease. In this report, we presented four cases of invasive squamous cell carcinoma accompanied by non-neoplastic atypical changes in ductal portions of AGMLG compatible with atypical ductal hyperplasia in breast adjacent to the carcinoma. This is a reactive phenomenon similar to that seen in apocrine/eccrine glands adjacent to squamous cell carcinoma. In a limited biopsy specimen, these areas should not be mistaken for adenocarcinoma.

A Case of Postpartum Anogenital Mammary-Like Gland Tumor with Focal Lactational Features: A Nomenclature Issue

Mammary-like glands (MLG) are considered to be a normal constituent of the anogenital region and can give rise to tumors with variable morphology that may be difficult to classify. We present a case of an anogenital mammary-like gland tumor in a breastfeeding woman showing morphological variation with lactational change, an unusual finding. We discuss the differing terminology used to report these tumors and the variation in assignment of their origin to MLG or ectopic breast tissue.

[Fibroepithelial tumors of the anogenital mammary-like glands]

Mammary-like glands are a normal anatomical component of the anogenital region. The tumors occurring in them morphologically mimic the similar diseases of the breast. The paper presents a case of vulvar fibroadenoma with leaf-like outgrowths and apocrine metaplasia in a 38-year-old female patient. It describes the clinical and morphological characteristics of fibroadenomas and benign phyllodes tumors in the anogenital region.

[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.

Molecular alterations in lesions of anogenital mammary-like glands and their mammary counterparts including hidradenoma papilliferum, intraductal papilloma, fibroadenoma and phyllodes tumor

Lesions affecting anogenital mammary-like glands (AGMLG) are histopathologically very similar to those seen in the breast but whether this morphological similarity is also reflected at the genetic level is unknown. To compare the underlying molecular mechanisms in lesions of AGMLG and their mammary counterparts, we analyzed the mutational profile of 16 anogenital neoplasms including 5 hidradenomas papilliferum (HP), 1 lesion with features of HP and fibroadenoma (FA), 7 FA, 3 phyllodes tumors (PhT)) and 18 analogous breast lesions (6 intraductal papillomas (IDP), 9 FA, and 3 PhT) by high-coverage next generation sequencing (NGS) using a panel comprising 50 cancer-related genes. Additionally, all cases were analyzed for the presence of a mutation in the MED12 gene. All detected mutations with allele frequencies over 20% were independently validated by Sanger sequencing (concordance: 100%). Mutations in PIK3CA, AKT1, MET, ABL1 and TP53 genes were found in lesions of AGMLG and also their mammary counterparts. The PI3K-AKT cascade plays a role in tumors arising at both sites. It appears that some histopathologically similar anogenital and breast lesions develop along similar molecular pathways.

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.

Hidradenoma Papilliferum With Oncocytic Metaplasia: A Histopathological and Immunohistochemical Study

Hidradenoma papilliferum is a benign cutaneous adnexal neoplasm, commonly occurring in the vulva and perianal region of adult women. It has characteristic histopathological features composed of anastomosing and branching tubules, lined by columnar cells, and a basal layer of myoepithelial cells. A 39-year-old woman was evaluated for 2 asymptomatic labial masses. The histopathological examination revealed a Bartholin's cyst and a hidradenoma papilliferum. The latter contains a distinct area of oncocytic/oxyphilic metaplasia. Immunohistochemical stains revealed positive staining for gross cystic disease fluid protein (GCDFP)-15 and androgen receptor. GATA-3, a protein expressed in sweat glands, highlights a similar positive staining pattern with weaker staining in areas of oncocytic metaplasia. P63 highlighted the myoepithelial differentiation. In situ hybridization for Human Papilloma Virus 6, 11, 16, and 18 was negative. P53 was negative and Ki-67 was low, confirming its benign nature. Oncocytes are enlarged epithelial cells with voluminous eosinophilic granular cytoplasm resulting from staining of nonribosomal cytoplasmic components. Few reports documented it in hidradenoma papilliferum. Our case demonstrated a florid distinct appearance of this metaplasia. The immunoprofiles of this oncocytic metaplasia such as p53 negativity and positivity for androgen receptor and GCDFP-15 demonstrates similarity to apocrine metaplasia in the breast. The authors' case demonstrates the benign nature of oncocytic metaplasia and supports the common origin of oncocytic cells and columnar cells in hidradenoma papilliferum.