Cutaneous Sweat Gland Carcinomas with Basaloid Differentiation

Reappraisal and literature review of primary cutaneous cribriform apocrine carcinoma

Primary cutaneous cribriform apocrine carcinoma (PCCAC) is an exceedingly rare sweat gland carcinoma. Clinically, it most often presents as a singular, asymptomatic nodule or cyst on the extremities of middle-aged patients and follows an indolent course. Both visceral and cutaneous cribriform tumors exist in nature. While a cribriform pattern is well recognized in tumors of visceral organs, there is a paucity in the literature on the defining characteristics for primary cutaneous tumors. Consensus regarding diagnostic criteria, etiology, and management protocols has yet to be achieved. We conducted an extensive literature review using pre-determined search criteria, resulting in 12 identified case reports and series on PCCAC that were subsequently analyzed. All data were compiled to provide a comprehensive update on the existing information regarding clinical presentation, histopathology, and management of reported PCCACs, as well as differential diagnosis, controversial issues, and recommendations for future considerations.

Endocrine Mucin-Producing Sweat Gland Carcinoma: A Systematic Review and Meta-Analysis

BACKGROUND

Endocrine Mucin-Producing Sweat Gland Carcinoma is a rare, under-reported cutaneous adnexal tumor that is often misdiagnosed and has an unknown incidence of metastasis.

OBJECTIVE

To determine the incidence of metastasis and tumor recurrence, as well as diagnostic accuracy and current trends in treatment modality.

METHODS

A search was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Tumor pathology and clinical data concerning demographics, presentation, diagnosis, treatment and follow-up were assessed.

RESULTS

A total of 36 publications with 110 cases were identified. Initial pathological diagnosis was incorrect in 45.5% of cases. One case of metastatic disease was reported. The incidence of locoregional recurrence was 10.6% over a mean follow-up period of 21.3 months. Of cases with known methods of resection, 34.6% were resected by excisional biopsy, 42.8% were resected by wide surgical excision, and 31.3% were cleared by Mohs micrographic surgery.

LIMITATIONS

The low reported incidence and level of evidence was suboptimal with only case reports and retrospective case studies being reported.

CONCLUSION

Reported cases of this pathology demonstrate poor diagnostic accuracy. High rates of misdiagnosis and inadequate definitive treatment suggest the need for more comprehensive work-up and management of lesions suspicious for this pathology.

Next Generation Sequencing analysis suggests varied multistep mutational pathogenesis for Endocrine Mucin Producing Sweat Gland Carcinoma with comments on INSM1 and MUC2 suggesting a conjunctival origin

Endocrine mucin-producing sweat gland carcinoma (EMPSGC) is a low-grade eyelid tumor. Small biopsies and insensitive immunohistochemistry predispose to misdiagnosis. We aimed to identify clarifying immunohistochemical and/or molecular markers. Clinicopathologic data (22 cases) was reviewed. Immunohistochemistry (Insulinoma-associated protein-1(INSM1), BCL-2, MUC2, MUC4, androgen-receptor, Beta-catenin, MCPyV) and next generation sequencing (MSK-IMPACT, 468 genes) was performed (3 cases). Female (n=15) and male (n=7) patients, mean-age 71.8 years (53-88), had eyelid/periorbital tumors (>90%) with mucin-containing solid/cystic neuroendocrine pathology. Immunohistochemistry (INSM1, BCL2, androgen-receptor, RB1, Beta-catenin) was diffusely-positive (5/5), MUC2 partial, MUC4 focal, and MCPyV negative. MSK-IMPACT identified 12 single-nucleotide-variants and one in-frame deletion in 3 cases, each with DNA damage response/repair (BRD4, PPP4R2, RTEL1) and tumor-suppressor pathway (BRD4, TP53, TSC1, LATS2) mutations. Microsatellite instability, copy number alterations, and structural alterations were absent. INSM1 and MUC2 are positive in EMPSGC. MUC2 positivity suggests conjunctival origin. Multistep pathogenesis involving DNA damage repair and tumor-suppressor pathways may be implicated.

Primary Cutaneous Cribriform Apocrine Carcinoma

Patient: Male, 56-year-old

Final Diagnosis: Apocrine carcinoma

Symptoms: Lesion on skin

Medication: —

Clinical Procedure: —

Specialty: Dermatology

An Update on Endocrine Mucin-producing Sweat Gland Carcinoma: Clinicopathologic Study of 63 Cases and Comparative Analysis

Endocrine mucin-producing sweat gland carcinoma (EMPSGC) is a rare, low-grade adnexal neoplasm with predilection for the periorbital skin of older women. Histologically and immunophenotypically, EMPSGC is analogous to another neoplasm with neuroendocrine differentiation, solid papillary carcinoma of the breast. Both lesions are spatially associated with neuroendocrine mucinous adenocarcinomas of the skin and breast, respectively. EMPSGC is ostensibly a precursor of neuroendocrine-type mucinous sweat gland adenocarcinoma (MSC), a lesion of uncertain prognosis. Non-neuroendocrine MSC has been deemed locally aggressive with metastatic potential, and previous works speculated that EMPSGC-associated (neuroendocrine-type) MSC had similar recurrence and metastatic potential with implications for patient follow-up. Only 96 cases of EMPSGC have been reported (12 cases in the largest case series). Herein, we present 63 cases diagnosed as "EMPSGC" in comparison with aggregated results from known published EMPSGC cases. We aim to clarify the clinicopathologic features and prognostic significance of the neuroendocrine differentiation of EMPSGC and its associated adenocarcinoma and to determine the nosological relevance of EMPSGC association in the spectrum of MSC histopathogenesis. Results established an overall female predominance (66.7%) and average presenting age of 64 years. EMPSGC lesions were associated with adjacent MSC in 33.3% of cases. The recurrence rate for neuroendocrine-type MSC was ~21%, less than the reported 30% for non-neuroendocrine MSC. There were no cases of metastasis. EMPSGC and neuroendocrine-type MSC are distinct entities with more indolent behavior than previously reported, supporting a favorable prognosis for patients.

Adenoid cystic carcinoma cytology: Salivary gland and nonsalivary gland

OBJECTIVES

Adenoid cystic carcinoma (ACCA) is an uncommon primary malignancy of salivary glands and rarely nonsalivary tissue. This study aims to evaluate the diagnostic accuracy of ACCA on fine needle aspiration (FNA) material and the associated challenges.

METHODS

A search on electronic pathology database from 2006 to 2016 at The Johns Hopkins Hospital found 83 cytology specimens diagnosed as ACCA, 49 with histology follow-up.

RESULTS

Fifty-two females and 31 males were found ranging from 37 to 95 years old (mean 62.5). The tumor size was 1 to 11.5 cm (mean 3.4). FNAs were performed on 46 salivary glands (54.88%), 12 head and neck masses (14.45%), 9 lymph nodes (10.84%), 9 tracheas/lungs (10.84%), 4 vaginal/perineum/gluteal masses (4.82%), and one for each kidney, liver and abdominal/pelvic mass (1.21%). 83 FNA diagnoses revealed 3 nondiagnostics (3.61%), 20 neoplasms with unspecified features (24.10%), 30 basaloid neoplasms (36.14%), 18 ACCA (21.69%), and 12 other malignancies (14.46%). The accuracy of FNA in diagnosis of ACCA comparing to histologic follow-up in 49 cases was 87.5% sensitivity, 66.67% specificity, with 92.11% positive predictive value and 54.55% negative predictive value. The most common mimicker was pleomorphic adenoma.

CONCLUSION

ACCA can be diagnosed not only in the salivary gland FNAs, but also respiratory tract, intra-abdominal, kidney, and gynecologic regions. FNA is a preferred technique to assess mass lesions. However, a diagnosis of ACCA on FNA material should be rendered with caution since there are benign and malignant neoplasms with overlapping features. Awareness of prior medical history and ancillary studies can improve the diagnosis.

Do not break a sweat: avoiding pitfalls in the diagnosis of sweat gland tumors

The group of malignant sweat gland neoplasms is characterized by a wide biologic spectrum, including tumors with indolent behavior, low-grade malignant potential with locally destructive tumor growth and high local recurrence rates and high-grade malignant potential characterized by risk for disseminated disease and disease-related mortality. Reliable diagnosis to predict behavior may be challenging for a number of reasons. The clinical presentation is often nonspecific. Many of the tumors are rare, and they are only infrequently encountered in routine diagnostic practice. A significant subset of tumors shows bland and innocuous histologic features. They are easily mistaken for benign tumors despite their potential for destructive growth and aggressive disease course. At the other end of the spectrum the tumors may resemble poorly differentiated carcinoma or adenocarcinoma and recognition relies entirely on sampling and carful histological examination. The tumors may be inseparable from cutaneous metastases from visceral primaries by morphology and immunohistochemistry, requiring careful clinical correlation and work-up. Conversely, cutaneous metastases are readily mistaken for cutaneous primary tumors. While the presence of a myoepithelial layer is a helpful feature in excluding metastatic deposits, it does not imply benign behavior of sweat gland tumors in general. The above issues and challenges are exemplified in the discussion of selected sweat gland carcinoma in this manuscript, with a focus on recently described entities and those with novel findings.

A case of eccrine porocarcinoma characterized by a progressive increase in the level of Ki-67 index: case report and review of literature

Background

Eccrine porocarcinoma is an extremely rare skin adnexal malignant neoplasia with highly invasive and metastatic potential. We report an additional case of eccrine porocarcinoma with intracranial metastases. This case is characterized by a complete record of the progress of eccrine porocarcinoma, its immunohistochemistry after three operations showed a progressive increase in the level of Ki-67 index.

Case presentation

We herein report a case of a 37-year-old-male with eccrine carcinoma occurring on the left posterior occipital scalp which invaded the skull and dura, presenting with progressive headache. This patient has performed three surgeries in total. During the last hospitalization, he underwent an extended surgical resection, lymphadenectomy, myocutaneous flap transplantation and vascular anastomosis in our institution. After surgery, he was treating with radiotherapy at 200 Gray in 12 fractions. But one year after the operation, he developed chest tightness, imaging examination and biopsy puncture revealed pulmonary metastasis.

Conclusion

Intracranial metastasis of eccrine porocarcinoma is a late event with poor prognosis. This case emphases on that progressively increased level of Ki-67 index may predict more chance to occur the intracranial metastasis of scalp eccrine porocarcinoma, long-term follow-up and appropriately dense follow-up interval is necessary.