Primary apocrine adenocarcinoma with neuroendocrine differentiation occurring on the pubic skin

Primary high-grade neuroendocrine carcinoma with positive steroid hormone receptors arising in the inguinal skin: A case report of An exceedingly rare entity

INTRODUCTION

Neuroendocrine tumors usually arise from the gastrointestinal and pulmonary tracts and rarely from the skin. We report a unique case of high-grade neuroendocrine carcinoma with positive steroid hormone receptors in the primary skin of the groin.

CASE PRESENTATION

A 79-year-old female presented with a lump in her left inguinal region for 15 years that grew gradually. The tumor cells were arranged in sheets, solid nests, and bands within a rich network of thin-walled capillaries. Mucin was abundant in the stroma, and the tumor cells exhibited high-grade lesions, significant necrosis, and frequent mitosis, with small scattered foci of low-grade components. Immunohistochemistry revealed that the tumor cells diffusely and strongly expressed cytokeratin, synaptophysin, chromogranin A, GATA3, CAM5.2, and estrogen and progesterone receptors; partially expressed AR and GCDFP15.

DIAGNOSIS

Based on pathological morphology, and immunohistochemical staining, it was confirmed as Primary high-grade neuroendocrine carcinoma with positive steroid hormone receptors arising in the inguinal skin. The patient underwent resection of the inguinal tumor and left inguinal lymph node dissection.

INTERVENTIONS

The patient has been followed up for 16 months and has not undergone further examinations or received additional treatment. There is no evidence of tumor recurrence at the site of the original surgical resection, and the patient general condition is satisfactory.

CONCLUSIONS

The morphology of this tumor is unique and previously unreported, further expanding the possible pathogenesis and histological morphologies of this tumor type.

Sweat-gland carcinoma with neuroendocrine differentiation (SCAND): a clinicopathologic study of 13 cases with genetic analysis

Low-grade neuroendocrine carcinoma of the skin (LGNECS) was proposed in 2017 as a new primary cutaneous neoplasm with neuroendocrine differentiation; however, it is not yet well known due to its rarity. Herein, we perform a detailed clinicopathologic analysis of 13 cases as well as panel DNA sequencing in three cases. The study included 12 males and 1 female with a median age of 71 (43-85) years. All lesions occurred on the ventral trunk. The mean tumor size was 2.2 (0.8-11.0) cm. The histopathology resembled that of well-differentiated neuroendocrine tumors (NETs) in other organs, but intraepidermal pagetoid spreading was seen in 8 (61.5%) cases and stromal mucin deposits in 4 (30.8%). Immunoreactivity for CK7, CK19, EMA, BerEP4, CEA, chromogranin A, synaptophysin, INSM1, GCDFP15, GATA3, ER, and bcl-2 were present in varying degrees in all tested cases. PTEN c.165-1G>A splice site mutation was detected by panel sequencing in one case, and GATA3 P409fs*99 and SETD2 R1708fs*4 in another case. Lymph node metastasis was seen significantly in cases with tumor size >2.0 cm [8/8 (100%) vs. 1/5 (20%)]. All three cases with size >3.0 cm were in unresectable advanced-stage [3/3 (100%) vs. 1/10 (10%)], and two of the three patients succumbed to the disease. The two cases of death revealed mild nuclear atypia (mitosis: 1/10 HPFs) and moderate nuclear atypia (2/10 HPFs). Thus, tumor size would be a better prognostic factor than nuclear atypia, mitotic count, and Ki67 index, unlike in NETs. These clinicopathologic and immunohistochemical features would represent the characteristics as skin adnexal tumors with apocrine/eccrine differentiation rather than NETs; therefore, we rename it as sweat-gland carcinoma with neuroendocrine differentiation (SCAND).

Independent primary cutaneous and mammary apocrine carcinomas with neuroendocrine differentiation: Report of a case and literature review

Cutaneous apocrine carcinomas share common features with their counterparts in the breast; hence, metastatic mammary carcinoma must be excluded before such lesions can be designated primary cutaneous neoplasms. Primary tumors from either source rarely exhibit neuroendocrine differentiation. We report a case of a 72-year-old female with a painless 1.2-cm scalp nodule. An incisional biopsy revealed dermal involvement by an invasive apocrine carcinoma juxtaposed to a benign apocrine cystic lesion. Immunohistochemically, the carcinoma expressed neuroendocrine proteins including synaptophysin, chromogranin, and CD56. A primary cutaneous apocrine carcinoma with neuroendocrine differentiation was favored, but additional investigations to exclude breast origin were recommended. These revealed a 1.1-cm nodule in the right breast, which proved to be an invasive ductal carcinoma, morphologically and immunophenotypically similar to the scalp lesion. This confounded the case, yet factors militating against metastatic breast carcinoma to skin included (a) the small size of the mammary tumor, (b) absence of other metastatic disease, and (c) juxtaposition of the scalp carcinoma to a putative benign precursor. Molecular studies were undertaken to resolve the diagnostic quandary. Single nucleotide polymorphism microarray analysis revealed distinct patterns of chromosomal copy number alterations in the two tumors, supporting the concept of synchronous and unusual primary neoplasms.

Unusual apocrine carcinoma with neuroendocrine differentiation: a cutaneous neoplasm may be analogous to neuroendocrine carcinoma with apocrine differentiation of breast

Cutaneous apocrine carcinoma (AC) is a rare adnexal neoplasm that histologically can mimic breast carcinoma metastatic to the skin or apocrine carcinoma arising in ectopic breast tissue. As extremely rare condition, neuroendocrine differentiation may be observed in AC although its etiology and pathogenesis is still unclear. We report here a case of unusual AC with neuroendocrine differentiation in right labium majus pudenda. A 43-year-old woman presented with a 6-month history of an asymptomatic pea-sized brownish nodule in right labium majus pudenda without enlargement of inguinal lymph nodes and bilateral breast nodules. The mass was totally resected. Microscopically, the tumor was solitary and located in the deep dermis without epidermal connection. Tumor cells were arranged in a micronodular or formed massive solid nests separated by densely fibroblastic stroma. Scattered glandular or rosette-like structures were identified within the tumor nodules. Immunohistochemically, the tumor cells were diffusely positive to CK7, CEA, GCDFP-15, synaptophysin, estrogen and progesterone receptors. Part of tumor cells expressed androgen receptor, but they were negative to CK20, CK5/6, p63 and S-100. Because of its rarity and histogenesis complexity, there exist diagnostic challenges for pathologists to differentiate cutaneous AC with neuroendocrine differentiation from other carcinomas with apocrine or neuroendocrine features. Our case demonstrates that the tumor shares some features with mammary carcinoma and might originate from mammary-like sweat gland in anogenital region. The results suggest that, for the first time, primary cutaneous AC with neuroendocrine differentiation may be analogous to the mammary neuroendocrine carcinoma with apocrine differentiation in histological feature and biological behavior. Virtual Slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/7732276716685708.

Immunohistochemical characterization of neuroendocrine differentiation of canine anal sac glandular tumours

Histological features and expression of neuroendocrine markers were examined in 69 samples of canine anal sac glandular carcinomas (ASGCs). The tumours were classified into solid, rosette and tubular types and mixtures of these types. Tumour-associated death in dogs with solid tumours and mixed tumours with solid components was higher than in dogs with rosette and tubular type tumours. Chromogranin A immunoreactivity was observed in 28 of 69 samples (40.6%) irrespective of histological type and was localized to the marginal areas of the tumour nest and the basal areas of the tubular and rosette structures. Neuron-specific enolase immunoreactivity in neoplastic epithelial cells was observed in 32 cases (46.4%) and was less frequently observed in the tubular type (14.3%). Synaptophysin expression was present in 15.9% of cases and was least frequent in the tubular type. Twenty-one of the 69 samples expressed more than two neuroendocrine markers and were classified as carcinomas with neuroendocrine differentiation. There was no relationship between neuroendocrine differentiation and clinical outcome. These results suggest that some ASGCs have neuroendocrine differentiation regardless of histological pattern, but clinical outcome is more related to the histological pattern than to neuroendocrine differentiation.

Goblet cell carcinoids and other mixed neuroendocrine/nonneuroendocrine neoplasms

Within the spectrum of neuroendocrine tumors arising in different organs, intermediate and controversial entities exist displaying a coexistence of neuroendocrine and nonneuroendocrine cell populations, and that are grouped under terms such as "goblet cell carcinoid", "mixed endocrine-exocrine carcinoma", "combined carcinomas", or "adenocarcinoma with neuroendocrine differentiation". These tumors may display variable amounts of the two components, potentially ranging from 1 to 99%, and variable structural patterns, ranging from single scattered neuroendocrine cells to a well-defined neuroendocrine tumor cell component organized in typical organoid, trabecular, or solid growth patterns. Although variably included in the site-specific World Health Organization classification schemes, clear definitions and diagnostic features are still missing, as well as a definite knowledge of their biological properties and histogenesis. In the present report, the main characteristics of tumors showing mixed neuroendocrine and nonneuroendocrine features will be described, using morphological patterns and site of origin as schematic guidelines. Moreover, molecular and clinical aspects, which might help to understand their possible histogenesis and biological behavior, will be reviewed.