Search

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., (© 2022. The Author(s).)

Out of all benign tumors of the ceruminous glands, syringocystadenoma papilliferum is the rarest and represents only 2% of cases. It is an extremely rare benign tumor that originates from modified apocrine sweat glands. The aim of this paper was to present, according to our findings, the 18th case of syringocystadenoma papilliferum in the external auditory canal, with a detailed review of its clinical, radiological and histomorphological characteristics. A 59-year-old man reported to our clinic due to a 5×5 mm papillomatous growth at the entrance to the right external auditory canal. Histopathology indicated, after an excisional biopsy, that it was a syringocystadenoma papilliferum. The resection lines were free of tumor tissue, and the patient has no signs of tumor recurrence. Although rare, it should be considered as a differential diagnosis of lesions in this region. Complete excision is mandatory in order to avoid recurrence and potential malignant alteration., (© 2022 The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.)

Abstract: Moll gland is a modified tubular-shaped apocrine sweat gland, which is located on the margin of the eyelid. Moll glands are also known as ciliary glands. The function of these glands was not well known for a long time. However, based on the different studies, it was proved that Moll glands are active from birth and have local immunologic function producing immunoglobulin A. We present a case of Moll adenocarcinoma, a type of apocrine carcinoma, arising from the right upper eyelid of a 57-year-old man. Although Moll gland cysts are frequently seen, this type of adnexal malignancy is extremely uncommon. These tumors can have variable presentation and behavior from less invasive forms to highly malignant metastatic recurrent lesions., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Mantle cell lymphoma is a rare malignancy to present in the orbit, comprising only 1-5% adnexal lymphomas. Endocrine mucin-producing sweat gland carcinoma (EMPSGC) is an equally uncommon adnexal tumor of sweat gland origin that may present on the eyelid. Herein we present a case of a 77-year old man with no previous cancer history who presented with painless progressive left globe proptosis and an enlarging left upper lid margin lesion, ultimately determined upon biopsy to be simultaneous orbital mantle cell lymphoma with systemic involvement and isolated eyelid EMPSGC. The pathogenesis, clinical manifestation, and management for each rare disease entity are reviewed and concept of collision tumors is discussed.

Apocrine hidrocystomas are benign cystic tumors derived from apocrine sweat glands; they are most commonly located in the skin of the head and neck regions. Ophthalmic occurrences typically appear at the lash line and canthi of the eyelid, although rare instances have been described in the conjunctiva, caruncle, and orbit. The authors illustrate an exceptional instance of a mobile episcleral cyst in a 12-year-old girl that developed about 2 years following strabismus surgery. The cyst was located anterior to the insertion of the left medial rectus and was excised in response to the patient's complaints of irritation. Histopathology of the excised specimen displayed an empty cyst lined by a double layer of cuboidal epithelium with the inner layer exhibiting apical decapitation secretion. Confirmatory immunohistochemistry demonstrated reactivity of both layers with CK7 and the outer myoepithelial layer with D2-40. Postoperative and traumatic cysts formed after interruption of the bulbar conjunctiva are usually conjunctival cysts lined by stratified squamous nonkeratinizing epithelium., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2022 The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc.)

Sweat gland carcinomas are a rare group of cancer, representing less than .01% of all diagnosed skin malignancies. We report the case of a 32-year-old male who presented with a fungating lesion on the posterolateral side of his left knee. Immunohistochemical results were positive for cytokeratin 5/6 and cytokeratin 7, consistent with possible eccrine gland origin. Our patient underwent wide local excision of the mass with lymph node dissection. Pathology confirmed the diagnosis of poorly differentiated carcinoma of possible adnexal, eccrine gland origin. He completed taxol/cisplatin-based chemotherapy and radiation. Surveillance imaging showed bilateral lung nodules, a right pleural effusion, and peritoneal carcinomatosis, which were diagnostic of metastatic carcinoma. He started carboplatin and epirubicin chemotherapy and has been doing well. Because standard of care treatment options for metastatic eccrine carcinoma have not been developed, it is imperative to report these cases to better understand these complex tumors and their treatment.

Background: Eccrine spiradenocarcinoma (SC), also known as malignant eccrine spiradenoma, is a rare malignant cutaneous adnexal neoplasm arising from long-standing benign eccrine spiradenoma. Malignant skin tumors rarely show direct intracranial invasion. However, once the intracranial structure is infiltrated, curative excision with sufficient margins can become extremely difficult, particularly when the venous sinuses are involved. No effective adjuvant therapies have yet been established. Here, we report an extremely rare case of scalp eccrine SC with direct intracranial invasion, which does not appear to have been reported previously., Case Presentation: An 81-year-old woman presented with a large swelling on the parietal scalp 12 years after resection of spiradenoma from the same site. The tumor showed intracranial invasion with involvement of the superior sagittal sinus and repeated recurrences after four surgeries with preservation of the sinus. The histopathological diagnosis was eccrine SC. Adjuvant high-precision external beam radiotherapy (EBRT) proved effective after the third surgery, achieving remission of the residual tumor. The patient died 7 years after the first surgery for SC., Conclusions: Scalp SC with direct intracranial invasion is extremely rare. Radical resection with tumor-free margins is the mainstay of treatment, but the involvement of venous sinuses makes this unfeasible. High-precision EBRT in combination with maximal resection preserving the venous sinuses could be a treatment option for local tumor control., (© 2022. The Author(s).)

Mixed tumour of the skin is a rare entity also known as chondroid syringoma and pleomorphic adenoma. These usually present as slow-growing skin nodules with a smooth surface, clear boundaries, and no ulceration. Case series exist describing pleomorphic adenomas in the periocular region including the lids and orbit, separate to the more familiar lacrimal gland pleomorphic adenoma. These may arise from accessory or ectopic lacrimal gland tissue but in the eyelids are more likely to arise from sweat glands in the skin. Histopathological analysis of these lesions is important to identify complete excision, minimising recurrences and in identifying rare but potential malignant transformation. We describe the clinical features and outcomes in three cases of pleomorphic adenoma with two at the medial canthus (including one recurrence) and one in the brow region.

From the first report in 1969 to the present day, diagnosis of eccrine porocarcinoma, also known simply as porocarcinoma (PC), remains a challenge. This review presents a concise update of the history, pathogenesis, epidemiology, diagnosis, management and prognosis of this rare sweat gland neoplasm. PC differentiates towards the intraepidermal spiral ducts in the eccrine gland, is more common in people aged > 60 years and often affects the head, neck and legs. PC presents as a dome-shaped papule, plaque or nodule growing over weeks to months. The exact incidence of PC is unknown but appears to be rising. Diagnosis is difficult because of variable presentations and similar clinical and histological features to cutaneous squamous cell carcinoma. Management involves removal of the tumour, usually using wide local excision or Mohs micrographic surgery. Prognosis is poor, with PC recurring after surgery in 35% of cases. Given the lack of standardized protocols and risk profiles, further studies would help improve the understanding of PC., (© 2022 British Association of Dermatologists.)

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.

Squamoid eccrine ductal carcinoma (SEDC) is a rare cutaneous neoplasm that often manifests as a plaque or nodule in sun-exposed areas of older patients. Herein, the authors report the first case of SEDC in the eyelid. A 76-year-old man presented with a 2.5 × 1.5 mm area of left upper eyelid erythema, thickening, ulceration, and scaling with madarosis superotemporally just above the lash line. Full-thickness wedge biopsy demonstrated irregular epithelial tubules with nuclear atypia and focal squamous differentiation, consistent with SEDC. The patient underwent Mohs resection and has had no recurrence approximately 27 months after surgical removal. The authors present this case to raise awareness of SEDC to ophthalmologists as all previous cases have been described in the nonophthalmic literature. A full-thickness biopsy is recommended to avoid misdiagnosing SEDC as squamous cell carcinoma (SCC), a less aggressive tumor. With greater awareness, there may be increased recognition of this likely underreported, more malignant entity., Competing Interests: The authors have no financial or conflicts of interest to disclose., (Copyright © 2022 The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc.)

Abstract: A 76-year-old female patient presented with a peculiar new exophytic-appearing, flesh-colored skin lesion on her left hallux. Owing to its atypical appearance, the neoplasm was biopsied. Histologic sections demonstrated numerous thickened, anastomosing cord-like structures composed of bland appearing adnexal keratinocytes attached to the epidermis and extending into the superficial dermis. Nearby areas exhibited papillomatosis, epidermal acanthosis, dense hyperparakeratosis, hypergranulosis, and superficial koilocytes, findings consistent with a verruca plantaris. A p16 stain was positive in many of the superficial epidermal keratinocytes. Human papillomavirus typing by in situ hybridization for the most common low-risk and high-risk types was also performed and was negative for these. We herein present an unusual case of a skin lesion which combines features of a poroma with a verruca plantaris. We further review what is known of the relationship between human papillomavirus and poroid neoplasms., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Male cases of accessory breast carcinoma and sweat gland carcinoma associated with extramammary Paget's disease of the axilla are uncommon. In clinical diagnosis and treatment, it is necessary to determine the disease carefully and make a reasonable treatment strategy according to the patient's situation., Case Presentation: We described two male cases of the special tumor with an axillary mass as the first clinical symptom, one of which was diagnosed as accessory breast cancer and the other as sweat gland cancer associated with extramammary Paget's disease. We treated the two diseases individually in the hopes of providing a reference for the diagnosis and management of diseases with axillary nodules as the initial symptom., Conclusions: The reports of these two cases can provide reference and corresponding thinking for clinical differentiation of axillary lymphadenopathy caused by different causes and subsequent treatment. These two cases may further enrich the database of rare cases and provide some ideas for the treatment of axillary lymphadenopathy caused by different causes., (© 2022. The Author(s).)

Background: Squamoid eccrine ductal carcinoma (SEDC) represents a subtype of eccrine carcinomas that are diagnostically challenging for both clinicians and dermatopathologists., Objective: To provide an updated review of SEDC and examine patient outcomes with different treatment modalities., Methods: A review of Ovid MEDLINE was performed to review the English language medical literature of SEDC., Results: A comprehensive review of clinical presentation, histologic findings, rates of lymphovascular and metastatic disease, treatment modalities and recurrence rates are reviewed., Limitations: There is a limitation on available data because of the rare incidence., Conclusions: SEDC is a rare adnexal neoplasm with a relatively high rate of local recurrence, lymphovascular invasion, perineural invasion, and metastases. Clinicians should be aware of this entity as close follow-up is essential to detect recurrence and metastatic disease. Mohs micrographic surgery seems to result in superior patient outcomes., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Objective: Eccrine porocarcinoma (EPC) is a malignant adnexal tumor accounting for about 0.005% of skin tumors. The standard treatment of EPC is the complete surgical excision of the primary lesion and of the clinically involved lymph nodes. There is limited evidence regarding the role of radiotherapy (RT) in managing EPC after surgery. Therefore, the aim of this multidisciplinary systematic review is to analyze the available evidence about postoperative RT in the curative treatment of EPC., Materials and Methods: A systematic search strategy was launched trough the main scientific databases including PubMed, Scopus and Cochrane. An additional manual search and a chain citation were performed about potentially relevant papers. The key words used for the search included "eccrine porocarcinoma", "porocarcinoma", "radiotherapy", "radiation therapy", "adjuvant radiotherapy" and "postoperative radiotherapy"., Results: A total of 104 publications were identified and 14 papers were included in the final analysis. The only articles found on adjuvant RT in EPC were case reports published between 1996 and 2019. There was a slight female prevalence (57% female/43% male) with a mean age of 65 years (range 37-85). Head-and-neck region was the most frequently involved anatomical site followed by legs., Conclusions: Adjuvant radiotherapy after surgical removal of EPC could be considered in cases with positive or close margins and in cases with unfavorable histological features. In view of limited literature data and the rarity of EPC the best treatment sequence should always be discussed within the frame of a multidisciplinary setting., Advances in Knowledge: adjuvant radiotherapy after surgical removal of EPC could be considered in cases with positive or close margins and in cases with unfavorable histological features.

Chondroid syringoma is a benign mixed tumour arising from the sweat glands which can be apocrine (found throughout the surface of the eyelid) or eccrine with a mean age of presentation being 50 years. Here we report two cases of chondroid syringoma of the upper eyelid, one in a young male patient and the other in an elderly woman. Both cases had well-defined lesions involving upper eyelid in the sub-brow region, underwent excisional biopsy, and histopathological findings were consistent with an apocrine type of chondroid syringoma in one case and eccrine type of chondroid syringoma in the second case. It is important to be aware of this entity as a rare cause of eyelid lesion due to the fact that although it is a benign neoplasm, incomplete excision may be associated with recurrence or malignant transformation., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Eccrine acrospiroma is a benign tumor of skin and adnexa arising from eccrine sweat gland epithelium. It is usually solitary, slow growing tumor commonly affecting extremities. Rarely it affects head and neck region, and extremely rare in parotid region. Females are affected more often. Treatment of choice is wide local excision with adequate skin margins. Although benign this tumor is very notorious for recurrence after inadequate resection. We describe here a case of young male patient with recurrent eccrine acrospiroma over parotid region which was managed by wide local excision with primary repair with excellent results.

Background: Syringoma is a benign sweat gland tumor., Aim: Vulvar location of syringoma is rare. Although the lesions are asymptomatic, it requires treatment due to the cosmetic concerns., Patients/methods: We present a 42-year-old woman with vulvar syringoma., Results: The patient treated with 577 nm pro-yellow laser with a great success., Conclusion: A 577 nm pro-yellow laser is a good alternative in the treatment of vulvar syringoma., (© 2021 Wiley Periodicals LLC.)

Apocrine hidrocystomas are benign cystic tumors derived from apocrine sweat glands; they are most commonly located in the skin of the head and neck regions. Ophthalmic occurrences characteristically appear at the lash line and canthi of the eyelid, although rare instances have been described in the conjunctiva, caruncle, and orbit. The authors describe an exceptional instance of a mobile epibulbar subconjunctival apocrine hidrocystoma in a 57-year-old woman without a history of previous ocular injury or surgery. Histopathology of the excised specimen displayed an empty cyst lined by a double layer of cuboidal epithelium with the inner layer exhibiting periodic acid-Schiff-positive apical decapitation secretion. Confirmatory immunohistochemistry included reactivity with cytokeratin-7, smooth muscle actin, D2-40, and CDGFP-15., Competing Interests: The authors have no financial or conflicts of interest to disclose., (Copyright © 2021 The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc.)

Background: Spiradenocarcinoma is a rare skin adnexal neoplasm that may behave aggressively. It is often associated with a benign slow-growing spiradenoma that has undergone malignant transformation. Given the paucity of cases in the literature, there is a lack of consensus on treatment., Methods: The terms 'malignant spiradenoma' or 'spiradenocarcinoma' were systematically used to search the PubMed, MEDLINE and Google Scholar databases. A total of 182 cases of spiradenocarcinoma were identified as eligible for this comprehensive literature review., Results: Spiradenocarcinoma was commoner in older age and Caucasian race. In most cases, surgical excision for local disease is the mainstay of treatment. Lymph node dissection is usually reserved for those with suspected or confirmed lymph node metastases. High rates of local recurrence (20.8%), metastasis (37.4%) and mortality (19.1%) were identified, prompting some authors to suggest regular follow up including chest X-rays and liver function tests., Conclusions: Patients with spiradenocarcinoma may benefit from a magnetic resonance imaging and fluorodeoxyglucose-positron emission tomography/computed tomography to establish the extent of disease. We recommend wide local excision as the treatment of choice to achieve surgical margins of ≥1 cm, with node resection to be determined on a case-to-case basis. Regular follow up is important given the high rate of local recurrence, metastasis and mortality. This should include an examination of the regional lymph nodes. Further research is required to refine an evidence-based approach to spiradenocarcinoma., (© 2021 Royal Australasian College of Surgeons.)

Objective: To analyze the prognosis of cutaneous adnexal malignancies, survival relative to surgical management, and utility of lymph-node biopsy., Design: Population-based study of the SEER-18 database from 1975 to 2016., Participants: 7591 patients with sweat gland carcinoma, hidradenocarcinoma, spiradenocarcinoma, sclerosing sweat duct tumor/microcystic adnexal tumor (SSDT/MAC), porocarcinoma, eccrine adenocarcinoma, and sebaceous carcinoma RESULTS: Five-year OS ranged from 68.0 to 82.6%, while 5-year DSS ranged from 94.6 to 99.0%. The majority of patients were treated with narrow (42.4%) or wide local excision (16.9%). DSS at 5 years showed that patients with stage IV had significantly poorer survival (50.3%) than I, II, or III (99.3%, 97.8%, and 89.0% respectively). 5-year OS was significantly higher for narrow excision (excision with < 1 cm margin, 78.5%) than observation (65.0%), excisional biopsy (66.8%), or wide local excision (WLE, 73.2%). Lymph-node biopsy was performed in a minority of cases (8.1%) and patients showed no significant difference in survival based on nodal status. The sensitivity and specificity of lymph-node biopsy for all malignancies were 46% and 80%, respectively. The PPV and NPV for that group were 0.46 and 0.80, respectively. Invasion of deep extradermal structures was a poor predictor of nodal positivity., Conclusions: These malignancies have excellent DSS. Narrow excisions demonstrate better 5-year DSS and OS compared with WLE. Lymph-node biopsy is a poor predictor of survival in advanced stage disease and utility is limited., (© 2020. Springer-Verlag GmbH Germany, part of Springer Nature.)

Competing Interests: The authors have no conflicts of interest to disclose and received no funding.

Abstract: Eccrine porocarcinoma (EPC) is a rare sweat gland malignancy. Recognition of histologic features is challenging, and specific pathologic features correlate with risk of poor outcome. This single-center retrospective review and case series of 58 EPC cases from 2000 to 2016 elucidates epidemiologic and pathologic characteristics of EPC. Pathology slides from 52 cases were analyzed by a dermatopathologist for standardized variable characteristics, including previously determined high-risk features (HRF) associated with poor prognosis. The incidence of EPC increased over the study period with 3 times more cases diagnosed in the last 4 years than in the first 4 years. Most cases were in the elderly males (mean age 75 years), and 50% were located in the head and neck region. Although 38% of tumors exhibited one histologic HRF, only 10% exhibited more than one. Of the HRF, a greater tumor depth was associated with both increased age (P = 0.04) and clear cell differentiation (P = 0.02). This study elucidates epidemiologic and pathologic features of EPC and highlights how age and clear cell differentiation can be associated with greater tumor depth, although further research is needed to determine whether clear cell differentiation is associated with poor clinical outcome., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Generalized eruptive syringomas are a very rare variant of syringoma which appear on the chest, neck, abdomen, upper and lower arms, thighs, legs and back. They often affect adolescent or post-adolescent females, although cases have been described in children and older adults. Generalized eruptive syringomas are mostly sporadic but familial cases, and those associated with eczematous skin conditions, solid organ transplants, renal cell carcinoma and some genodermatoses have also been reported. Although eruptive syringomas may resemble cutaneous mastocytosis, disseminated granuloma annulare, eruptive xanthomata, steatocystoma multiplex, eruptive velus hair syndrome, verruca plana and other skin conditions clinically, the histological appearance characterized by upper dermal epithelial cords with a tendency to ductule formation and tadpole extension of outer epithelial layer is diagnostic. We report the case of a 20-year-old Nigerian woman with generalized eruptive syringoma., Competing Interests: None

Coined in 1961 by Hirsch and Helwig, the term chondroid syringoma refers to a rare mixed tumour of subcutaneous tissue. Histologically, these tumours are almost identical to pleomorphic adenomas, arising from salivary glands. With the obvious difference being the presence of sweat gland tissue (syringoma) within a matrix of cartilage (chondroid). These mixed tumours remain scarce throughout the world, with an incidence of less than 0.098%. The vast majority of cases are reported in middle-aged and older adults, where they typically present as painless swellings in the head and neck, which gradually grow in size., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Abstract: Intraconal orbital hidrocystoma is a very rare entity. Herein, a 6-month old boy with an intraconal apocrine hidrocystoma will be reported. The patient presented with a left-sided mild proptosis and significant anisometropic hypermetropia. Clinical examinations revealed choroidal folds and optic disc blurring in the left eye. Orbital MRI disclosed an intraconal well-defined cystic lesion that was hypointense in T1 and hyperintense in T2 weighted images. The lesion was excised completely through a lateral orbitotomy and diagnosed histologically as an apocrine hidrocystoma. Excepting partial improvement of anisometropia, other clinical signs were improved after surgery., Competing Interests: The authors declare that there is no conflict of interest., (Copyright © 2020 by Mutaz B. Habal, MD.)

Hidradenocarcinoma is a rare, aggressive cancer arising from sweat glands. Hidradenocarcinoma has no definitive histologic features compared to its benign hidradenoma, thereby posing a diagnostic challenge for clinicians and pathologists. This novel case report demonstrates specific MRI signs that suggested malignant degeneration of hidradenoma., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Squamoid eccrine ductal carcinoma (SEDC) is a rare and under-recognized primary cutaneous tumor with a high risk for local recurrence and metastasis. The tumor has a biphasic histologic appearance consisting of a superficial portion indistinguishable from squamous cell carcinoma (SCC) and a deeper component demonstrating eccrine ductal differentiation. Because of superficial sampling, SEDC often is misdiagnosed as SCC during the initial biopsy. The diagnosis usually is made during complete excision when deeper tissue is sampled. Confirmation of the diagnosis can be achieved by immunohistochemical positivity for carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA), cytokeratin (CK) 5/6, and p63. In this article, we review the clinical and histologic details of 5 patients with SEDC who underwent successful treatment with Mohs micrographic surgery (MMS) at a single institution between November 2018 and May 2020. We also review the histologic patterns that helped distinguish SEDC from SCC upon complete excision. Our findings support the use of MMS as the treatment of choice for SEDC, given that all of the patients we reviewed required more than 1 Mohs stage for complete tumor clearance, and none demonstrated evidence of recurrence or metastasis after a mean follow-up period of 11 months.

Solid-cystic hidradenoma is a benign cutaneous tumor that is most commonly found in the head, neck, trunk, and upper extremity regions of patients in the middle to older aged groups. Presentation on lower extremities and in particular on the foot is uncommon. Nodular hidradenomas represent a dermatological pitfall, being difficult to differentiate from basal cell carcinoma and melanoma. We report on a 53-year-old male patient with a pigmented nodular hidradenoma on his ankle that was surgically removed. We discuss histopathology and differential diagnosis of this eccrine tumor of skin. This is the second reported case in the English literature.

Introduction: Eccrine and apocrine hidrocystomas are uncommon, benign, cystic proliferations of the sweat glands usually located on the head and neck area., Objectives: To describe the key clinical and histopathological characteristics of a large series of hidrocystomas in Greece to improve diagnostic accuracy, and to perform a historical review of the medical term hidrocystoma., Methods: A case series of 22 hidrocystomas from 20 consecutive patients treated with surgery at University Hospital of Heraklion in Crete, Greece, from January 1, 1998 to January 1, 2020 was performed along with a comprehensive historical literature review of the term hidrocystoma and its corresponding term hydatis from ancient Greek literature to the present. Data were obtained from medical records. All patients had a histopathologically confirmed diagnosis of hidrocystoma. Formalin-fixed paraffin-embedded (FFPE) sections of 22 tumors of the 20 consecutive patients were retrieved from the pathology laboratory archive and stained for SMA, p63, and GCDFP-15 with immunochemistry and periodic acid-Schiff (PAS) histochemical stain., Results: Overall, 22 hidrocystomas (11 apocrine and 11 eccrine hidrocystomas) surgically excised from 20 patients were included in this study. Of the 20 patients, 10 (50%) were male and 10 (50%) were female, with a mean age of 56 ± 15 years. Hidrocystomas commonly occurred on the eyelids (73%), inner canthus (9%), eyebrow (4.5%), neck (4.5%), nose (4.5%), and ear (4.5%). All apocrine hidrocystomas stained positive for SMA, GCDFP-15, CAM 5.2, PAS, and PAS-D. No recurrence was observed., Conclusions: Here we have presented the clinicopathological characteristics of the largest case series of hidrocystomas in Europe and the Mediterranean region. Only apocrine hidrocystomas stained positive for SMA, GCDFP-15, CAM 5.2, PAS, and PAS-D.

Rationale: Eccrine poroma, a benign cutaneous neoplasm originating from the intraepidermal portion of the eccrine sweat duct, is relatively common in clinical practice. Nevertheless, the 1 presenting as spindle-shaped plaque is extremely rare and easily misdiagnosed as seborrheic keratosis or other dermatoses. Thus, the current study demonstrates a case of eccrine poroma with unique clinical manifestation., Patients Concerns: A 47-year-old man presented with a spindle-shaped plaque on his left sole for 6 years., Diagnoses: Based on the clinical and histopathological manifestations, diagnosis of eccrine poroma was established., Interventions: Surgical excision under local anesthesia was performed., Outcomes: No recurrence or malignant transformation occurred within 6-month follow-up., Lessons: Eccrine poroma typically presents as a dome-shaped nodule on palm or sole. But this case reminded us the lesion presenting as a spindle-shaped plaque on sole can not rule out the possibility of eccrine poroma., Competing Interests: The authors have no funding and conflicts of interests to disclose., (Copyright © 2021 the Author(s). Published by Wolters Kluwer Health, Inc.)

Hidradenoma is a rare benign neoplasm, with few cases reported to involve the eyelid. When affecting the eyelid, hidradenomas may mimic other benign or malignant lesions. Rarely, a benign hidradenoma may transform into a malignant hidradenoma and metastasize. The authors present a case of a benign hidradenoma arising from the eyelid, presenting with rapid growth, ulceration, and bleeding, suggestive of a malignant lesion., Competing Interests: The authors have no financial or conflicts of interest to disclose., (Copyright © 2021 The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc.)

Background/objectives: Primary cutaneous mucinous carcinoma (PCMC) of the head and neck is a rare pathologic entity that is an adenocarcinoma of the eccrine sweat glands. Though it has low metastatic potential, it does have a significant recurrence rate. Due to its rarity, its clinical features are not well-known., Methods: The authors searched the National Cancer Database (NCDB) for all cases of PCMC with primary sites of the skin of the head and neck confirmed histologically diagnosed from 2004 to 2016. Those with missing survival information were excluded. Kaplan-Meier (KM) and Cox proportional-hazards models were used to analyze the epidemiology and survival outcomes of PCMC., Results: The authors analyzed 289 cases. Females were more commonly affected (58.8%; P < 0.05) with the most common primary sites being the eyelid (41.9%) and scalp/neck (25.3%). The average age of diagnosis was 63.8 years (± SD 12.5). Almost all patients received surgery as standalone treatment (92.7%) with wide local excision being the common surgery performed (36.3%). Mohs surgery represented 15.2% of surgically treated cases. Mean overall survival (OS) was 11.4 years with 5-year and 10-year OS being 85.0% and 78.0%, respectively. Most cases were localized at diagnosis with only 2% metastatic at presentation. KM analysis indicated that surgical procedure type, age, tumor diameter, Charlson-Deyo Comorbidity Score, facility type, and stage were significant predictors of OS (P < 0.05). Cox proportional-hazards analysis did not reveal independent association of the aforementioned factors with OS., Conclusion: Primary cutaneous mucinous carcinoma has an excellent prognosis with 98% of cases being diagnosed in Stage I and Stage II. As most cases present in the eyelid, special attention should be given to surgical treatment to ensure optimal aesthetic outcomes in this sensitive region. This study represents the largest cohort of head and neck PCMC studied to date., Competing Interests: The authors report no conflicts of interest., (Copyright © 2020 by Mutaz B. Habal, MD.)

Background: Hidradenoma papilliferum is a rare benign neoplasm arising from apocrine glands. It occurs commonly on the anogenital region of middle-aged women. It usually presents as a slow growing, solitary asymptomatic, skin colored or red nodule less than 1 cm in diameter., Case Presentation: The case is a 38-year-old, white woman who presented with a painful nodule occurring within a month in the himenal region of the posterior vaginal introitus. The nodule was excisied and the histology revealed a hidradenoma papilliferum. The diagnosis and treatment of hidradenoma papilliferum is possible with surgical removal and histopathological evaluation of nodules., Conclusion: When an adult woman presents with a noduler lesion in the anogenital area, sexually transmitted diseases and other benign and malignant vulvar lesions, as well as malignant transformation is very rare but,should be kept in mind; however because it has been reported and long-term clinical follow-up is suggested.

Syringocystadenoma papilliferum is a rare, benign adnexal tumor of eccrine or apocrine origin that typically presents at birth or before puberty. Syringocystadenoma papilliferum is associated with a nevus sebaceus in about 40% of cases. We present a 50-year old woman with a pink-orange plaque and nodule on the scalp, consistent with syringocystadenoma papilliferum that arose within a nevus sebaceus.

Background: Conventional treatment options for periorbital syringomas are often unsatisfactory because of inevitable surface damage from the procedure and frequent recurrence rate of the tumors., Objectives: The authors sought to ascertain the efficacy and safety of intralesional electrosurgery utilizing a monopolar radiofrequency device with a single insulated microneedle for the treatment of periorbital syringomas., Methods: A retrospective analysis was performed employing data from medical records, routine questionnaires, and clinical photographs of 55 patients with periorbital syringoma who underwent intralesional electrosurgery., Results: Approximately one-half of the patients (50.9%) experienced marked resolution after 1 treatment. The lesion clearance rate increased and lesion severity decreased each time the treatment was repeated. No persistent therapy-related adverse event was found except transient erythema or crusting., Conclusions: Intralesional electrosurgery with insulated microneedle is an effective and safe treatment option for periorbital syringomas., (© 2019 The Aesthetic Society. Reprints and permission: journals.permissions@oup.com.)