Anatomoclinical study of 30 cases of sclerosing sweat duct carcinomas (microcystic adnexal carcinoma, syringomatous carcinoma and squamoid eccrine ductal carcinoma)

A Case of Squamoid Eccrine Ductal Carcinoma of the Auricle Mimicking Perichondritis

The subtype of eccrine carcinoma known as squamoid eccrine ductal carcinoma (SEDC) is rare; only 38 cases, including only 6 cases in the ear, have been documented in the literature. This may be the first case to focus on the fact that SEDC, located within the dermal and subcutaneous layers, spares the epidermis histopathologically, which can cause clinicians to confuse SEDC with acute perichondritis.

Periocular Microcystic Adnexal Carcinoma: A Case Report and a Major Review

PURPOSE

To describe a patient with periocular microcystic adnexal carcinoma (MAC) and to review the clinical presentation, systemic work-up, histopathologic features, and outcome of all previously reported periocular MAC.

METHODS

A major literature review. PubMed/MEDLINE and Google Scholar databases were searched for all well-documented cases of periocular MAC.

RESULTS

The final analysis yielded 93 patients with MAC, 48 (52%) females, 39 (42%) males, and 6 with sex not specified (6%) with an average age of 56 years (range 3 days-95 years). Most tumors were localized to the eyebrow (26/93, 28%) and lower eyelid (20/93, 22%). Of patients with known information, MAC most commonly presented as a nodule (37/68, 54%) or plaque (20/68, 29%) with poorly-defined margins (20/51, 39%) and distortion of eyelid margin (13/51, 25%). Orbital involvement at any point of the disease course was seen in 20 of 93 (22%) patients. An accurate histopathologic diagnosis on initial biopsy was made in 25 of 70 (36%) cases. Initial management included surgical excision (47/93, 51%), Mohs micrographic surgery (17/93, 18%), and excision with frozen section control of margins (8/93, 9%). Aggressive or recurrent MAC was managed with multimodal therapies, including adjuvant radiation (10/34, 29%). The average follow-up after the last treatment was 3 years (median 2, range 0.2-20 years). In total, 33 of 86 (38%) tumors recurred, and 6 of 87 (7%) metastasized. Disease-related mortality occurred in 3 of 79 (4%) of patients.

CONCLUSIONS

Periocular MAC is frequently misdiagnosed on initial biopsy and has a tendency for recurrence and locally aggressive behavior, highlighting the importance of accurate timely diagnosis, and appropriate management.

Rare syringoid eccrine carcinoma of the upper lip and nasal base treated with resection and subsequent innovative reconstruction using an Abbé flap, turbinate flaps and three-stage forehead flap: a case report

Background

Although syringoma is a common benign tumour of the sudoriferous gland, there is also an extremely rare malignant form known as syringoid eccrine carcinoma (SEC). SEC usually exhibits slow growth with deep invasion and a frequent tendency to relapse. The treatment of choice is radical wide resection, which poses a difficult reconstructive problem, especially when the tumour is located in the centre of the face.

Case presentation

In this case, a 70-year-old man was diagnosed with an SEC at the same location as a benign syringoma of the upper lip and nasal base that had undergone primary excision 7 years prior. Primary radical resection was performed with immediate Abbé flap reconstruction. Nevertheless, histology revealed positive margins, and 3 additional re-excisions were needed to achieve clear margins. Four months after the initial resection, the patient had undergone an innovative reconstruction technique including not only the Abbé flap but also a turbinate flap harvested with functional endonasal surgery and a three-stage forehead flap.

Conclusion

To the best of our knowledge, this is the first case report of a suspect malignant transformation of a benign syringoma after 7 years. In addition, from oncoplastic and reconstructive points of view, the bilateral use of the turbinate flap for reconstructing the intranasal lining of the alar base is unusual, and the use of functional endonasal surgery in nasal reconstruction for reducing the risk of damaging the vascular supply of the flap is innovative.

Recent Advances on Immunohistochemistry and Molecular Biology for the Diagnosis of Adnexal Sweat Gland Tumors

Simple Summary

Cutaneous sweat gland tumors form an extremely diverse and heterogeneous group of neoplasms that show histological differentiation to the sweat apparatus. Due to their rarity, wide diagnostic range, and significant morphological overlap between entities, their accurate diagnosis remains challenging for pathologists. Until recently, little was known about the molecular pathogenesis of adnexal tumors. Recent findings have revealed a wide range of gene fusions and other oncogenic factors that can be used for diagnostic purposes and, for some, can be detected by immunohistochemistry. Among other organs containing exocrine glands, such as salivary glands, breasts, and bronchi, most of these biomarkers have been reported in homologous neoplasms that share morphological features with their cutaneous counterparts. This review aims to describe these recent molecular and immunohistochemical biomarkers in the field of sweat gland tumors.

Abstract

Cutaneous sweat gland tumors are a subset of adnexal neoplasms that derive or differentiate into the sweat apparatus. Their great diversity, rarity, and complex terminology make their pathological diagnosis challenging. Recent findings have revealed a wide spectrum of oncogenic drivers, several of which are of diagnostic interest for pathologists. Most of these molecular alterations are represented by gene fusions, which are shared with other homologous neoplasms occurring in organs containing exocrine glands, such as salivary and breast glands, which show similarities to the sweat apparatus. This review aims to provide a synthesis of the most recent immunohistochemical and molecular markers used for the diagnosis of sweat gland tumors and to highlight their relationship with similar tumors in other organs. It will cover adenoid cystic carcinoma (NFIB, MYB, and MYBL1 fusion), cutaneous mixed tumor (PLAG1 fusion), cylindroma and spiradenoma and their carcinomas thereof (NF-κB activation through CYLD inactivation or ALKP1 hotspot mutation), hidradenoma and hidradenocarcinoma (MAML2 fusion), myoepithelioma (EWSR1 and FUS fusion), poroma and porocarcinoma (YAP1, MAML2, and NUTM1 fusion), secretory carcinoma (ETV6, NTRK3 fusion), tubular adenoma and syringo-cystadenoma papilliferum (HRAS and BRAF activating mutations). Sweat gland tumors for which there are no known molecular abnormalities will also be briefly discussed, as well as potential future developments.

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.

Next-generation sequencing implicates oncogenic roles for p53 and JAK/STAT signaling in microcystic adnexal carcinomas

Microcystic adnexal carcinoma is a locally aggressive sweat gland carcinoma characterized by its infiltrative growth and histopathologic overlap with benign adnexal tumors, often posing challenges to both diagnosis and management. Understanding the molecular underpinnings of microcystic adnexal carcinoma may allow for more accurate diagnosis and identify potential targetable oncogenic drivers. We characterized 18 microcystic adnexal carcinomas by targeted, multiplexed PCR-based DNA next-generation sequencing of the coding sequence of over 400 cancer-relevant genes. The majority of cases had relatively few (<8) prioritized somatic mutations, and lacked an ultraviolet (UV) signature. The most recurrent mutation was TP53 inactivation in four (22%) tumors. Frame-preserving insertions affecting the kinase domain of JAK1 were detected in three (17%) cases, and were nonoverlapping with TP53 mutations. Seven (39%) cases demonstrated copy number gain of at least one oncogene. By immunohistochemistry, p53 expression was significantly higher in microcystic adnexal carcinomas with TP53 mutations compared with those without such mutations and syringomas. Similarly, phospho-STAT3 expression was significantly higher in microcystic adnexal carcinomas harboring JAK1 kinase insertions compared with those with wild-type JAK1 and syringomas. In conclusion, microcystic adnexal carcinomas are molecularly heterogeneous tumors, with inactivated p53 or activated JAK/STAT signaling in a subset. Unlike most other nonmelanoma skin cancers involving sun-exposed areas, most microcystic adnexal carcinomas lack evidence of UV damage, and hence likely originate from a relatively photo-protected progenitor population in the dermis. These findings have implications for the biology, diagnosis, and treatment of microcystic adnexal carcinomas, including potential for therapeutic targeting of p53 or the JAK/STAT pathway in advanced tumors.

An Overview of Uncommon Cutaneous Malignancies, Including Skin Appendageal (Adnexal) Tumours and Sarcomas

A standardised classification of malignant skin appendageal (adnexal) tumours and sarcomas is required for improved patient management and prognosis. This has been hindered by considerable morphological variation both within and between tumour types, the use of many synonyms for the same tumour types and variation in classification between pathologists. This update uses the improved classification in the 2018 WHO classification of skin tumours as the basis to discuss malignant skin appendageal tumours, sarcomas and cutaneous metastases that regularly present to skin cancer clinicians, multidisciplinary skin cancer teams and tumour boards, with current evidence for management, where appropriate.

Squamoid eccrine ductal carcinoma of the ear helix

Chronic cutaneous ulcer on the ear helix of 80-year-old male was diagnosed with squamoid eccrine ductal carcinoma (SEDC). SEDC is characterized by both atypical squamous and ductal differentiation. SEDC frequently appears on sun-exposed areas. It could show local recurrence despite complete resection. These characteristics demand cautious attention to SEDC.

Syringomatous Tumour Presenting as Inversion of a Supernumerary Nipple

Syringomatous tumour (SyT) is a rare type of benign locally infiltrative tumour with debated origin. Because of the growth pattern, SyT can be mistaken for a malignant tumour, and it is therefore important to keep this diagnosis in mind. This case presents a woman with two supernumerary nipples on each side of the abdomen. One of the nipples was inverted with a small palpable firm mass in close relation to the nipple, leading to referral to the breast surgery department. SyT occurring in a supernumerary nipple and presenting with the symptoms described in this case has to our knowledge never been described previously.

[Microcystic adnexal carcinoma: A case report]

We report a case of microcystic adnexal carcinoma in a 80-year-old woman. This is a rare malignant adnexal cutaneous tumor with glandular and follicular differentiation, rare, often asymptomatic, with late diagnosis and slow growth, locally aggressive and rarely metastatic. The distinction with other benign and malignant skin tumors is difficult.

Ductal eccrine carcinoma of the axilla: a diagnostic pitfall

Ductal eccrine carcinoma (DEC) is a rare sweat gland carcinoma with ductular differentiation. Clinically, it is characterized by a slowly growing, hardened plaque or nodule predominantly located on the head and neck. Histologically, DEC shares similar features to invasive breast carcinoma, thus causing great diagnostic challenges. We report a 69-year-old woman who presented with a hardened plaque on the axilla. A skin biopsy was performed and metastatic invasive breast carcinoma could not be ruled out. Complete excision and further workup were subsequently conducted, leading to the diagnosis of estrogen receptor positive DEC with associated axillary lymph node metastases. The patient received adjuvant radiotherapy to the left axilla and was started on oral letrozole. She is disease-free 14 months after initial diagnosis.

Squamoid Eccrine Ductal Carcinoma: A Clinicopathologic Study of 30 Cases

Squamoid eccrine ductal carcinoma is a poorly documented skin adnexal carcinoma showing squamous and duct differentiation. It is regarded to be of low-grade malignant potential, but limited follow-up information is available. To study their clinical behavior and histologic features, 30 squamoid eccrine ductal carcinomas were identified from departmental and referral files. Hematoxylin and eosin-stained sections were reviewed, and immunohistochemistry for carcinoembryonic antigen and epithelial membrane antigen was examined to confirm duct differentiation. Clinical follow-up was obtained from patient records and referring pathologists. The tumors presented as nodules or plaques (median size, 1.0 cm; range, 0.5 to 2.5 cm) with a predilection for the head and neck (77%). The patients were elderly (median age, 79.5 y; range, 10 to 96 y) with a male predominance. Histologically, these poorly demarcated tumors were characterized by an infiltrative growth pattern within the dermis and additional invasion of subcutis in 70%. Median tumor thickness was 4.3 mm (range, 1.5 to 18 mm). Superficially, the tumors resembled well-differentiated squamous cell carcinoma. In the deeper reaches, they were organized in cords and strands showing duct differentiation in a desmoplastic stroma. Cytologic atypia was moderate to severe. Ulceration (47%), necrosis (23%), and perineural and lymphovascular infiltration (27% and 6%, respectively) were additional features. Follow-up data (median, 29 mo; range, 7 to 99), available for 24 patients (80%), revealed a local recurrence rate of 25%. Three patients had lymph node metastasis, and 1 patient died of metastatic disease. Our study outlines the histologic characteristics of squamoid eccrine carcinoma and emphasizes its clinical behavior with risk for local recurrence and potential for more aggressive behavior with metastasis and rare disease-related mortality.

Squamoid eccrine ductal carcinoma

Squamoid eccrine ductal carcinoma is an eccrine carcinoma subtype, and only twelve cases have been reported until now. It is a rare tumor and its histopathological diagnosis is difficult. Almost half of patients are misdiagnosed as squamous cell carcinoma by the incisional biopsy. We report the thirteenth case of squamoid eccrine ductal carcinoma. Female patient, 72 years old, in the last 6 months presenting erythematous, keratotic and ulcerated papules on the nose. The incisional biopsy diagnosed squamoid eccrine ductal carcinoma. After excision, histopathology revealed positive margins. A wideningmargins surgery and grafting were performed, which again resulted in positive margins. The patient was then referred for radiotherapy. After 25 sessions, the injury reappeared. After another surgery, although the intraoperative biopsy showed free surgical margins, the product of resection revealed persistent lesion. Distinction between squamoid eccrine ductal carcinoma and squamous cell carcinoma is important because of the more aggressive nature of the first, which requires wider margins surgery to avoid recurrence.