Eccrine porocarcinoma (malignant eccrine poroma): a clinicopathologic study of 69 cases

Clinicopathological comparison of eccrine poroma and porocarcinoma: Ki-67 index is not a decisive factor

BACKGROUND

Eccrine poroma (EP) and porocarcinoma (EPC) arise from the intraepidermal part of the sweat gland. Clinically they resemble each other and cannot be distinguished without histopathological examination. EPC has been described as aggressive; however, the Ki-67 index is scarcely reported. The aim of this study was to compare clinicopathological factors between EP and EPC with special interest in Ki-67 index.

METHODS AND FINDINGS

50 EP and 22 EPC samples with clinical data from 48 EP and 21 EPC patients were collected from the Finnish Biobanks. We performed immunohistochemistry using a Ki-67 antibody on a tissue microarray and analysed the Ki-67 index with ImmunoRatio 2.5-program. We analysed 48 EP and 21 EPC samples. EPC patients were older (p = 0.019) and their tumours larger (p = 0.003) but other than these there were no statistically significant differences. Ki-67 ratios were similar (medians: EP 0.6% and EPC 0.5%). The median follow-up time in EP group was 12 (range 1.5-30.6 years) and in EPC group 7 years (range 0.75-20.3 years). The survival of EP patients was better than EPC patients but did not reach statistical significance and, in the Cox multivariate analysis only age had statistically significant effect (HR 1.061, 95% CI 1.026-1.099, p < 0.001). Ki-67 index had no statistically significant effect on survival in EPC group in the Cox univariate analysis (HR 0.746, 95% CI 0.390-1.43, p = 0.378).

CONCLUSIONS

EPC patients were older and their tumours larger. There was no difference in Ki-67 index between EP and EPC groups. In the Cox multivariate analysis only age had a statistically significant effect on survival. According to our findings Ki-67 index might not be a decisive factor in the prognosis of EPC. Further studies to validate our current findings are warranted.

Eccrine poroma versus eccrine porocarcinoma: a comparative study of clinicopathological features

BACKGROUND

Eccrine porocarcinoma (EPC) is a rare cutaneous neoplasm, commonly arising from its benign counterpart, eccrine poroma (EP), but potential unrevealed clinicopathological differences between them are not well understood.

OBJECTIVES

This study aimed to identify clinicopathological features of EP and EPC and describe the factors that may be associated with the malignant transformation of EP by comparing the two groups.

METHODS

A total of 37 cases of EP and 22 cases of EPC diagnosed between January 2017 and June 2023 were retrospectively reviewed, and the clinical and histopathological characteristics were compared using statistical methods.

RESULTS

Clinical and histopathologic data such as age, gender, site, clinical presentation, and histopathologic characteristics were collected. The EPC group was more common in older patients, with more cases located in exposed areas, and the patients with EPC had larger lesions with a higher incidence of ulceration. Histopathological features showed significant differences in tumor architecture, ulceration, squamous differentiation, spindle cell changes, central necrosis, and diffuse inflammatory infiltration between the two groups.

STUDY LIMITATIONS

This study has limitations due to a small number of cases with potential experimental bias.

CONCLUSION

The clinicopathological features of EP and EPC were compared in this study and the results may assist clinicians in diagnosis and management of these tumors by helping to identify potential factors associated with the malignant transformation of EP.

Radiotherapy and prognostic factors in adnexal carcinomas: A retrospective study of 657 patients from the French CARADERM network

BACKGROUND

Cutaneous adnexal carcinomas are a heterogeneous group of rare neoplasms. Surgical excision is the first-line treatment in localized stage. The use and effectiveness of radiotherapy have not been thoroughly evaluated in these neoplasms.

OBJECTIVES

The present work analyses prognostic factors on outcomes in skin adnexal carcinomas, based on data from the CARADERM (CAncers RAres DERMatologiques) database.

METHODS

Data were collected retrospectively including demographic data, tumour types and therapeutic characteristics of all patients included in the CARADERM database, with at least one informative follow-up visit. Analyses were performed on three populations: patients with complete resection of the primary tumour (ADJ/primary population), patients achieving complete remission after complete resection of a recurrent tumour (ADJ/recurrent population) and patients with unresectable locally advanced or metastatic tumours (ADV/MET population). Overall and recurrence/progression-free survivals at 3-year were analysed using Cox regression models.

RESULTS

Radiotherapy did not affect overall survival (OS) in the ADJ/primary population. Adjusted recurrence-free survival (RFS) was significantly lower in the radiotherapy group in ADJ/primary group. Older patients had significantly poorer OS and RFS. Tumour size and immunosuppression were significantly associated with poorer RFS only. Radiotherapy had no effect on OS and RFS in the ADJ/recurrent population. Age was the only factor associated with a poorer OS. Radiotherapy was significantly associated with longer progression-free survival (PFS) in age-sex adjusted analysis in the ADV/MET population, without effect on OS.

CONCLUSIONS

Our study shows that age, tumour size and immunosuppression are significantly associated with survival in localized adnexal carcinomas. Radiotherapy may improve PFS in the ADV/MET population but not in localized and recurrent carcinomas after complete excision.

Whole-exome sequencing identifies distinct genomic aberrations in eccrine porocarcinomas and poromas

BACKGROUND

Eccrine porocarcinoma (EPC) is a rare malignant skin tumor arising from the eccrine gland. Investigations into the genomic landscape of EPC have uncovered potential drivers of its development and progression. However, there is limited information on the discrepancies between EPC and its benign counterpart, eccrine poroma (EP).

METHODS

Formalin-fixed paraffin-embedded (FFPE) samples from 15 EPCs and 5 EPs were retrieved from Helsinki Biobank and Finnish Clinical Biobank Tampere. One EPC was found to be digital papillary adenocarcinoma in review of diagnoses. Whole-exome sequencing was used to conduct a comprehensive analysis to elucidate the genomic features of EPCs and EPs.

RESULTS

There was general heterogeneity within EPCs and EPs, with discrepancies such as exclusive TP53, NCOR1, and CDKN2A mutations in EPCs and a higher mutational load in EPCs than in EPs. Furthermore, we identified alterations in pathways associated with cell adhesion and the extracellular matrix in EPCs, while pathways associated with ketone body and amino acid metabolism were altered in EPs. The MAPK and Ras signaling pathways were enriched in genes mutated only in EPCs.

CONCLUSIONS

EPCs and EPs are generally heterogeneous tumor entities with a few distinct discrepancies from each other. The findings from this study emphasize the need to further verify the roles of disrupted genes and pathways in the initiation and progression of EPCs and EPs.

[Cutaneous adnexal tumours: Development and synthesis of diagnostic fusion genes]

Cutaneous adnexal tumours are a heterogeneous group of epithelial lesions that includes tumours with follicular, sudoral and/or sebaceous differentiation, or even several combined lines of differentiation. Over the last few years, molecular analysis of these lesions has allowed to identify specific molecular events responsible for tumour development in an increasing number of tumour types. Like other rare neoplasms, such as soft tissue tumours, adnexal tumours display fusion genes resulting from chromosomal translocations that may be specific for the diagnosis if molecular data are properly integrated in the clinical and morphological setting. Molecular testing of adnexal tumours is valuable as it allows to strengthen the robustness of the diagnosis for a group of tumours displaying a wide morphological spectrum. It has allowed to refine the diagnostic criteria and to develop increasingly specific diagnostic immunostainings. Finally, molecular testing has been responsible for the identification of new entities or morphological subtypes of previously known entities. The aim of this review is to provide an update on cutaneous adnexal tumours associated with fusion genes and to evaluate the impact of molecular data on the diagnosis of these lesions.

Sentinel Lymph Node Biopsy: Is There a Role in Non-Melanoma Skin Cancer? A Systematic Review

BACKGROUND/OBJECTIVES

Sentinel Lymph Node Biopsy (SLNB) aims at identifying clinically occult nodal metastases. It is the standard staging procedure for patients with T1b to T4 primary cutaneous melanoma. Moreover, it is recommended whenever the risk of a positive SLNB is >5%, according to the National Comprehensive Cancer Network Melanoma guidelines. When considering Non-Melanoma Skin Cancer (NMSC), the SLNB could play a role in tumors that mainly spreads via lymphatics, but strong evidence is missing. In this paper, the hot topics and controversies are reviewed; Methods: A PRISMA systematic review was carried out on the PubMed (MEDLINE) library from 2004-2024, searching for studies on SLNB in NMSC; Results: Seventy articles and 6379 patients undergoing SLNB for Squamous Cell Carcinoma (SCC), Merkel Cell Carcinoma (MCC), and Porocarcinoma were included. Overall, the SLNB positivity rate in these NMSCs was 24.4%, with an SNLB detection rate of 97.6%. Specifically, the SLNB positivity rate was 12.3% for high-risk cutaneous SCC, 24.4% for anogenital SCC, 29.3% for MCC, and 30.6% for Porocarcinoma. Most papers concluded that SLNB is safe, feasible, and significant in these malignancies; Conclusions: SLNB should be discussed and offered to every patient with MCC, and it should be discussed and considered in "high risk" SCC and Porocarcinoma for staging and prognostic purposes, aiming to identify a subgroup of patients who may benefit the most from early treatments.

Diagnosis and Management of Malignant Epithelial Nail Unit Tumors

Background: Malignant epithelial nail unit tumors pose significant diagnostic and therapeutic challenges due to their clinical presentation often mimicking benign conditions and due to the need to preserve as much nail unit function as possible during surgery. Early detection is crucial, even if none of these tumors represent a life-threatening disease. Objectives: This review focus on squamous cell carcinoma, verrucous carcinoma, eccrine porocarcinoma, onychocytic carcinoma, basal cell carcinoma, malignant onychopapilloma, malignant onycholemmal cyst and onycholemmal carcinoma. Methods: Existing literature on the aforementioned tumors has been revised and synthesized. Results: Clinical presentation, pathology, diagnostic procedures, risk factors and the challenges associated with surgical management have been described in detail. Conclusions: Malignant epithelial tumors of the nail unit require careful evaluation and management due to their complex presentation. Early detection and an informed surgical approach are essential to improve patient outcomes and minimize complications.

Porocarcinoma with orbital metastasis, a case report with review of literature

We present a patient who presented with an orbital mass lesion which was a metastatic lesion from a porocarcinoma of the scalp with progressive deterioration of the patient.A 78-year-old male presented with functional decline and a rapidly growing scalp lesion of 3 months duration. In addition to the scalp lesion, Computed Tomography showed an incidental finding of a left lateral orbital wall tumour. Fine-needle aspiration of the two lesions revealed malignant cells with similar morphologies. Punch biopsy of the scalp lesion showed histological features suggestive of a porocarcinoma. Patient underwent palliative radiotherapy and immunotherapy and subsequently succumbed to the disease.

ALA-PDT combined with CO2 laser in the treatment of malignant hidroacanthoma simplex: A case report

Hidroacanthoma simplex (HS) is a rare skin appendage tumor that typically appears on the trunk and lower limbs in the elderly. Although HS is a predominantly benign condition, the presence of cellular atypia and dermal infiltration on histological examination indicates malignant HS (MHS). 5-aminolaevulinic acid photodynamic therapy (ALA-PDT) uses a photosensitizer and corresponding light source to cause irreversible damage or death of target cells through a photochemical reaction. Here, we reported the successful treatment of a MHS patient with ALA-PDT using plum-blossom needle pretreatment combined with CO2 laser. After five courses of ALA-PDT, the lesions were completely resolved, and the autonomic activity and smooth surface of the left ring finger were restored. This suggests that ALA-PDT is an effective, minimally invasive and safe treatment modality for MHS.

Porocarcinomas with PAK1/2/3 fusions: a series of 12 cases

AIMS

Porocarcinoma is a malignant sweat gland tumour differentiated toward the upper part of the sweat duct and may arise from the transformation of a preexisting benign poroma. In 2019, Sekine et al. demonstrated the presence of YAP1::MAML2 and YAP1::NUTM1 fusions in most poromas and porocarcinomas. Recently, our group identified PAK2-fusions in a subset of benign poromas. Herein we report a series of 12 porocarcinoma cases harbouring PAK1/2/3 fusions.

METHODS AND RESULTS

Five patients were male and the median age was 79 years (ranges: 59-95). Tumours were located on the trunk (n = 7), on the thigh (n = 3), neck (n = 1), or groin area (n = 1). Four patients developed distant metastases. Microscopically, seven cases harboured a benign poroma component and a malignant invasive part. Ductal formations were observed in all, while infundibular/horn cysts and cells with vacuolated cytoplasm were detected in seven and six tumours, respectively. In three cases, the invasive component consisted of a proliferation of elongated cells, some of which formed pseudovascular spaces, whereas the others harboured a predominant solid or trabecular growth pattern. Immunohistochemical staining for CEA and EMA confirmed the presence of ducts. Focal androgen receptor expression was detected in three specimens. Whole RNA sequencing evidenced LAMTOR1::PAK1 (n = 2), ZDHHC5::PAK1 (n = 2), DLG1::PAK2, CTDSP1::PAK1, CTNND1::PAK1, SSR1::PAK3, CTNNA1::PAK2, RNF13::PAK2, ROBO1::PAK2, and CD47::PAK2. Activating mutation of HRAS (G13V, n = 3, G13R, n = 1, Q61L, n = 2) was present in six cases.

CONCLUSION

Our study suggests that PAK1/2/3 fusions is the oncogenic driver of a subset of porocarcinomas lacking YAP1 rearrangement.

Eccrine Poroma of the Palm: A Case Report and Literature Review

Eccrine poroma is a non-cancerous tumor that arises from the intraepidermal portion of the eccrine sweat glands. It usually appears as a solitary lesion on an extremity, commonly on the foot or sole, and is often subject to delayed or inaccurate diagnosis in clinical settings. This article describes a rare case of eccrine poroma located on the palm. It discusses the clinical and histological features, diagnostic difficulties, recurrence risks, and the possibility of malignant transformation associated with this condition.

Gene expression profiling in porocarcinoma indicates heterogeneous tumor development and substantiates poromas as precursor lesions

BACKGROUND AND OBJECTIVES

Malignant sweat gland tumors are rare, with the most common being eccrine porocarcinoma (EP). Approximately 18% of benign eccrine poroma (EPO) transit to EP. Previous research has provided first insights into the mutational landscape of EP. However, only few studies have performed gene expression analyses. This leaves a gap in the understanding of EP biology and potential drivers of malignant transformation from EPO to EP.

METHODS

Transcriptome profiling of 23 samples of primary EP and normal skin (NS). Findings from the EP samples were then tested in 17 samples of EPO.

RESULTS

Transcriptome profiling revealed diversity in gene expression and indicated biologically heterogeneous sub-entities as well as widespread gene downregulation in EP. Downregulated genes included CD74, NDGR1, SRRM2, CDC42, ANXA2, KFL9 and NOP53. Expression levels of CD74, NDGR1, SRRM2, ANXA2, and NOP53 showed a stepwise-reduction in expression from NS via EPO to EP, thus supporting the hypothesis that EPO represents a transitional state in EP development.

CONCLUSIONS

We demonstrated that EP is molecularly complex and that evolutionary trajectories correspond to tumor initiation and progression. Our results provide further evidence implicating the p53 axis and the EGFR pathway. Larger samples are warranted to confirm our findings.

Genexpressionsprofile beim Porokarzinom deuten auf heterogene Tumorentwicklung hin und untermauern Porome als Vorläuferläsionen

Hintergrund und Ziele

Maligne Schweißdrüsentumoren sind selten, wobei das ekkrine Porokarzinom (EP) das häufigste ist. Etwa 18 % der benignen ekkrinen Porome (EPO) entwickeln sich zum EP. Wissenschaftliche Studien haben erste Einblicke in die Mutationslandschaft von EPs geliefert. Allerdings wurden in nur wenigen Studien Genexpressionsanalysen durchgeführt. Dies hinterlässt eine Lücke im Verständnis der EP‐Biologie und potenzieller Treiber der malignen Transformation von EPO zu EP.

Methoden

Es wurde eine Transkriptomanalyse von 23 Proben primärer EP und normaler Haut (NH) durchgeführt. Die Ergebnisse aus den EP‐Proben wurden dann an 17 EP‐Proben getestet.

Ergebnisse

Das Transkriptom‐Profiling zeigte eine Vielfalt in der Genexpression und deutete auf biologisch heterogene Subeinheiten sowie eine weit verbreitete Herunterregulierung von Genen im EP hin. Herunterregulierte Gene umfassten CD74, NDGR1, SRRM2, CDC42, ANXA2, KFL9 und NOP53. Die Expressionsniveaus von CD74, NDGR1, SRRM2, ANXA2 und NOP53 zeigten eine stufenweise Abnahme der Expression von NH über EPO zu EP, was die Hypothese unterstützt, dass das EPO einen Zwischenschritt in der EP‐Entwicklung darstellt.

Schlussfolgerungen

Die Studie zeigt, dass das EP molekular komplex ist und der evolutionäre Verlauf der Tumorinitiierung und ‐progression entspricht. Die Ergebnisse legen eine Beteiligung der p53‐Achse und des EGFR‐Signalwegs nahe. Eine größere Probenanzahl ist erforderlich, um diese Ergebnisse zu bestätigen.

Adnexal neoplasms of the eye

Adnexal neoplasms of the eyelid encompass a wide variety of benign and malignant tumors of sebaceous, follicular, and sweat gland origin. Due to the specialized structures of the eyelid, these neoplasms present differently when compared with those of other locations. Although most dermatologists and ophthalmologists are familiar with the commonly reported adnexal tumors of the eyelid, such as hidrocystoma, pilomatrixoma, and sebaceous carcinoma, many other adnexal neoplasms have been reported at this unique anatomic site. Accurate and timely identification of these neoplasms is essential, as alterations of eyelid anatomy and function can have a negative impact on eye health, vision, and quality of life. We review the clinical and histopathologic features of common and rare eyelid adnexal neoplasms and discuss proposed treatment options.

Navigating Head and Neck Porocarcinoma: Systematic Review with Special Emphasis on Surgical Safety Margins

Eccrine porocarcinoma, sharing many features with other skin tumours, is diagnostically challenging. A conventional biopsy might be misleading and surgical excision becomes a primary diagnostic tool and a treatment method. However, the data on surgical safety margins are not consistent. We present a systematic review analysing the surgical margins of porocarcinoma in the head and neck area, which was conducted across the PubMed, Cochrane, and Web of Science databases including studies published from inception to November of 2023. In this systematic review, the PRISMA-ScR checklist was used, and a Cohen's Kappa coefficient of 0.92 was applied, indicating very good agreement between reviewers. Out of 529 identified articles, 18 studies yielding 20 cases in total were selected for a thorough analysis. Nine (45%) cases were observed in the facial regions, eight (40%) on the scalp, and three (5%) on the neck. The primary treatment of choice was wide local excision with safety margins ranging from 3 to 22 mm (mean: 10.1). It demonstrated that surgical margins do not differ by age or anatomic regions, with the main point of reference being the tumour size. As observed, the bigger the tumour, the wider the safety margins were. However, the limited disclosure of surgical safety margins in analysed case reports impeded our ability to define the minimum safety margins. Further investigation and a consensus on recommended safety margins are required.

Eccrine porocarcinoma in the tempus of an elderly woman: A case report

BACKGROUND

Eccrine porocarcinoma (EPC) is a rare skin tumor that mainly affects the elderly population. Tumors often present with slow growth and a good prognosis. EPCs are usually distinguished from other skin tumors using histopathology and immunohistochemistry. However, surgical management alone may be inadequate if the tumor has metastasized. However, currently, surgical resection is the most commonly used treatment modality.

CASE SUMMARY

A seventy-four-year-old woman presented with a slow-growing nodule in her left temporal area, with no obvious itching or pain, for more than four months. Histopathological examination showed small columnar and short spindle-shaped cells; thus, basal cell carcinoma was suspected. However, immunohistochemical analysis revealed the expression of cytokeratin 5/6, p63 protein, p16 protein, and Ki-67 antigen (40%), and EPC was taken into consideration. The skin biopsy was repeated, and hematoxylin and eosin staining revealed ductal differentiation in some cells. Finally, the patient was diagnosed with EPC, and Mohs micrographic surgery was performed. We adapted follow-up visits in a year and not found any recurrence of nodules.

CONCLUSION

This case report emphasizes the diagnosis and differentiation of EPC.

Poroid Neoplasms: A Clinicopathological Study of 13 Cases

Introduction

Poroid neoplasms (PN) are a heterogeneous group of tumors deriving from sweat glands and folliculo-sebaceous units. Their histological classification and clinical features are challenging. Our aim was to report clinicopathological features of poroid neoplasms.

Methods

It is a retrospective study including all cases of poroid neoplasms registered at our Pathology laboratory of Niamey National Hospital (February 2020-February 2024).

Results

We registered 13 cases of benign poroid neoplasms: 10 classic poromas (CP) (76.9%), 2 poroid hidradenomas (PH) (15.4%) and 1 dermal duct tumor (DDT) (7.7%). Nine cases (69.2%) had preoperative clinical diagnosis of malignancy. The mean age was 41.1 years (range of 12-70 years) with a slight female predominance. Only 4/13 cases (30.8%) had classical palmoplantar locations. The tumors mean size was 3.7 cm (range of 0.4-8 cm). Clear cells were present in 7 cases (53.8%), apocrine ductal differentiation (mixed or pure) in 6 cases (46.2%), keratin horns in 2 cases (15.4%), squamous eddies in 6 cases (46.2%), melanin pigments in 1 case (7.7%) and sebaceous differentiation in 2 cases (15.4%).

Conclusions

Unlike what is classically reported, our study shows that apocrine ductal differentiation, younger age and non-palmoplantar locations are common in poroid neoplasms.

Gene fusions in poroma, porocarcinoma and related adnexal skin tumours: An update

Poroma is a benign sweat gland tumour showing morphological features recapitulating the superficial portion of the eccrine sweat coil. A subset of poromas may transform into porocarcinoma, its malignant counterpart. Poroma and porocarcinoma are characterised by recurrent gene fusions involving YAP1, a transcriptional co-activator, which is controlled by the Hippo signalling pathway. The fusion genes frequently involve MAML2 and NUTM1, which are also rearranged in other cutaneous and extracutaneous neoplasms. We aimed to review the clinical, morphological and molecular features of this category of adnexal neoplasms with a special focus upon emerging differential diagnoses, and discuss how their systematic molecular characterisation may contribute to a standardisation of diagnosis, more accurate classification and, ultimately, refinement of their prognosis and therapeutic modalities.

Pazopanib elicits remarkable response in metastatic porocarcinoma: a functional precision medicine approach

Metastatic porocarcinomas (PCs) are vanishingly rare, highly aggressive skin adnexal tumors with mortality rates exceeding 70%. Their rarity has precluded the understanding of their disease pathogenesis, let alone the conduct of clinical trials to evaluate treatment strategies. There are no effective agents for unresectable PCs. Here, we successfully demonstrate how functional precision medicine was implemented in the clinic for a metastatic PC with no known systemic treatment options. Comprehensive genomic profiling of the tumor specimen did not yield any actionable genomic aberrations. However, ex vivo drug testing predicted pazopanib efficacy, and indeed, administration of pazopanib elicited remarkable clinicoradiological response. Pazopanib and its class of drugs should be evaluated for efficacy in other cases of PC, and the rationale for efficacy should be determined when PC tumor models become available. A functional precision medicine approach could be useful to derive effective treatment options for rare cancers.

Eccrine Porocarcinoma of the Vulva With Sarcomatoid Transformation, a New Human Papillomavirus-associated Malignancy? Case Report and Review of the Literature

Eccrine porocarcinoma is a rare cutaneous neoplasm, and rarer still in the anogenital region. In the vulva, the most common carcinoma by far is squamous cell carcinoma; however, eccrine porocarcinoma can arise at this site. As the distinction between porocarcinoma and squamous cell carcinoma has important prognostic implications at other cutaneous sites, it stands to reason that it may have these same implications in the vulva. We present a case of an eccrine porocarcinoma in the vulva of a 70-year-old woman that, in addition, showed sarcomatoid transformation. This tumor harbored human papillomavirus-18 DNA and mRNA, raising the question of the role of the oncogenic virus in sweat gland neoplasms of the vulva.

Eccrine Poroma with Concurrent Basal Cell Carcinoma: A Rare Combination

Eccrine poroma (EP) is a benign skin appendicular tumor that differentiates into the terminal sweat duct and is often differentiated from basal cell carcinoma (BCC) and seborrheic keratosis. This report describes a 58-year-old woman who presented with left occipital plaque. Histopathological analysis showed that the tumor cells were located in the lower part of the epidermis. The tumor cells were cuboidal or circular basal-like cells of the same size. The surrounding cells were not arranged in a palisade shape. Scattered tumor clusters composed of basal-like cells were also seen in the dermis, staining basophilic, and the surrounding cells were arranged in a palisade pattern. Immunohistochemistry showed that BerEP4, epithelial membrane antigen EMA, carcinoembryonic antigen CEA, Bcl-2, CD10, CK7 were positive, AR, PAS were negative. According to the pathological examination and immunohistochemical results, a case of eccrine poroma with concurrent basal cell carcinoma was diagnosed.

Genetics of adnexal tumors: An update

Cutaneous adnexal tumors form a vast heterogeneous group that include frequent entities that are mostly benign, as well as rare tumors that are occasionally malignant. In contrast to cutaneous tumors arising from the interfollicular epidermis that develop as a result of accumulation of UV-induced DNA damage (basal cell carcinoma, squamous cell carcinoma), the oncogenesis of adnexal tumors is related to a broad spectrum of genetic mechanisms (e.g., point mutation, fusion genes, viral integration, etc.). In this setting, specific and recurrent genetic alterations have been progressively reported, and these allow better classification of these entities. For certain of them, immunohistochemical tools are now available, enabling precise integrated histological and molecular diagnosis since certain entities are linked to well-defined alterations. In this context, we aim in this review to summarize the main molecular tools currently available for the classification of adnexal tumors.

Porocarcinoma Concurrent with Psoriasis Vulgaris: The First Report

Psoriasis is a common chronical inflammatory skin disease with a prevalence of 2%-4% worldwide. In contrast, porocarcinoma is a relatively rare cutaneous neoplasm and an associated localization of both lesions is rare. Here, we describe the first case of porocarcinoma in a patient with psoriasis. A 71-year-old Japanese man was referred to our clinic for evaluation of nodule within a keratotic plaque of 20-years history on his leg. Histopathological examination showed that the plaque revealed acanthosis with regular elongation of rete ridges, agranulosis and the presence of Munro microabscesses. In contrast, massive proliferation of atypical poroid cells and a few cuticular cells in the dermis were seen in the nodule. We speculated that it is likely the porocarcinoma was caused by the elevated risk of skin cancer due to chronic inflammatory process of psoriasis itself in our patient.

Eccrine Porocarcinoma: Clinical and Histopathological Study of 14 Patients with Special Emphasis on Sentinel Lymph Node Biopsy

Eccrine porocarcinoma is a rare skin adnexal tumour that affects elderly people. Most eccrine porocarcinomas are stage I or II according to the American Joint Committee on Cancer. The prognosis is good in early stages, but worsens when advanced. Since information on the use of sentinel lymph node biopsy in these patients is scarce, this study examined the records of all patients with eccrine porocarcinoma treated at Helsinki University Hospital during a 17-year period and focused on sentinel lymph node biopsy patients. The study identified 14 patients (9 male, 5 female). There were 2 metastases to the lymph nodes and 2 recurrences at initial referral to our institution. All primary tumours had wide local excision and 6 patients also had sentinel lymph node biopsy, of whom none had positive lymph nodes. There were no new metastases or recurrences during follow-up. Three patients died of causes other than eccrine porocarcinoma. When comparing the wide local excision only and wide local excision with sentinel lymph node biopsy groups, no parameters reached statistical significance. The decision process of the multidisciplinary tumour board meeting on whether to perform sentinel lymph node biopsy was not clear, perhaps due to the limited knowledge of eccrine porocarcinoma. Further studies and international collaboration are warranted.

When to sweat: A history of chemotherapy in malignant sweat gland tumors. A unique case report and literature review

Sarcomatoid sweat gland carcinomas are rare among cutaneous cancers, with less than 20 cases described. A 54-year-old woman with sarcomatoid sweat gland carcinoma of the right upper extremity suffered extensive recurrence at 15 months, unresponsive to chemotherapy. There is no standard treatment or chemotherapy regimens for metastatic sweat gland carcinoma.

Eccrine Porocarcinoma: A Review of the Literature

Eccrine porocarcinoma (EPC) constitutes a rare malignant adnexal tumor, which accounts for about 0.005-0.01% of all cutaneous malignancies. It may develop de novo or arise from an eccrine poroma, after a latency period of years or even decades. Accumulating data suggest that specific oncogenic drivers and signaling pathways may be implicated in its tumorigenesis, while recent data have demonstrated a high overall mutation rate attributed to UV exposure. Diagnosis may be challenging and should rely on the combination of clinical, dermoscopical, histopathological and immunohistochemical findings. The literature is controversial regarding tumor behavior and prognosis and, therefore, there is no consensus on its surgical management, utility of lymph-node biopsy and further adjuvant or systemic treatment. However, recent advances in tumorigenesis of EPC may aid in the development of novel treatment strategies, which could improve survival of advanced or metastatic disease, such as immunotherapy. This review presents an update of the epidemiology, pathogenesis and clinical presentation of EPC and summarizes current data on diagnostic evaluation and management of this rare cutaneous malignancy.

[Translated article] Poroma: A Retrospective Series of 80 Patients at a Tertiary Care Hospital

BACKGROUND

Poroma is a benign, exclusively cutaneous, adnexal tumor with a predilection for palmoplantar skin.

OBJECTIVE

To analyze the clinical characteristics of poroma in our population.

MATERIAL AND METHODS

Retrospective study of patients diagnosed with poroma between 2002 and 2021. We conducted a chart review to record age; sex; number, location, and diameter of lesions; time since onset; clinical characteristics; suspected clinical diagnosis; resection margin status; recurrences; and follow-up duration. Categorical variables were compared using the Fisher exact test. Continuous variables were compared using the t test or the Mann-Whitney U test depending on whether they were normally or nonnormally distributed.

RESULTS

We studied 80 patients (31 women and 49 men) with a median (interquartile range [IQR]) age of 65.5 (29) years. Median time since onset of poroma was 12 (21) months. Median lesion diameter was 8 (7)mm, and none of the patients had multiple lesions. The lesions were located on the head and neck in 13 cases, the trunk in 13, the upper extremities in 11, and the lower extremities in 43. Twenty-three lesions (28.8%) were located at acral sites (5 on the palms and 18 on the soles). Women were more likely to have scalp lesions (P=.041). Acral lesions were more likely to be erythematous (P=.014). Five patients experienced local recurrence.

CONCLUSIONS

Although poromas are particularly common in acral locations (especially the feet), most of the lesions in our series (71.3%) were located elsewhere. Acral lesions were more likely to show the classic clinical features of erythema and exophytic growth.

Poroma: A Retrospective Series of 80 Patients at a Tertiary Care Hospital

BACKGROUND

Poroma is a benign, exclusively cutaneous, adnexal tumor with a predilection for palmoplantar skin.

OBJECTIVE

To analyze the clinical characteristics of poroma in our population.

MATERIAL AND METHODS

Retrospective study of patients diagnosed with poroma between 2002 and 2021. We conducted a chart review to record age; sex; number, location, and diameter of lesions; time since onset; clinical characteristics; suspected clinical diagnosis; resection margin status; recurrences; and follow-up duration. Categorical variables were compared using the Fisher exact test. Continuous variables were compared using the t test or the Mann-Whitney U test depending on whether they were normally or nonnormally distributed.

RESULTS

We studied 80 patients (31 women and 49 men) with a median (interquartile range [IQR]) age of 65.5 (29) years. Median time since onset of poroma was 12 (21) months. Median lesion diameter was 8(7)mm, and none of the patients had multiple lesions. The lesions were located on the head and neck in 13 cases, the trunk in 13, the upper extremities in 11, and the lower extremities in 43. Twenty-three lesions (28.8%) were located at acral sites (5 on the palms and 18 on the soles). Women were more likely to have scalp lesions (P=.041). Acral lesions were more likely to be erythematous (P=.014). Five patients experienced local recurrence.

CONCLUSIONS

Although poromas are particularly common in acral locations (especially the feet), most of the lesions in our series (71.3%) were located elsewhere. Acral lesions were more likely to show the classic clinical features of erythema and exophytic growth.

A case of racemiform trichoblastoma in a dog

Trichoblastoma, which is common in dogs, is now occurring with other cellular changes outside the recognized forms to warrant their continuous evaluation for proper elucidation even as their causes largely remain unknown. A case at hand involved a 9-year-old Caucasian dog, which weighed 35 kg with chief complaint of a progressive bleeding mass on the scalp. The dog had an up-to-date vaccination record and all vital parameters were within optimum ranges. The surgical excision of the firm, solitary, and alopecic mass with traumatized upper surface revealed the presence of a well-demarcated and unencapsulated mass composed of grapes-like nests of basaloid epithelial cells within follicular stroma devoid of stromal necrosis, inflammatory cellular infiltration, and neoplastic epidermal connection. However, there was tissue necrosis, hemorrhages, and inflammatory cellular infiltrates on the exposed upper part of the traumatized growth. Immunohistochemical analysis showed positive reactivity to AE1/AE3, CK5/6, and p63 but negative immunoreactivity to CK7, CK20, CEA, and TTF-1. The histomorphological and immunohistochemical evaluation of the mass on the scalp of the dog suggested a solitary racemiform trichoblastoma with a traumatized exposed upper part despite basal cell carcinoma mimicry where histological diagnosis currently hold sway over immunohistochemical evaluation.

An Unusual Case of a Scrotal Porocarcinoma and Review of the Literature

ABSTRACT

Porocarcinomas are rare tumors derived from the acrosyringium and eccrine ducts, which most commonly occur on the lower extremities or head and neck region in older adults. Microscopically, they invariably demonstrate continuity with the epithelium, showing downgrowth of broad anastomosing bands with more infiltrative intradermal cords and nests of pleomorphic tumor cells with ductal lumina; an associated poroma may also be seen. We report an unusual case of a porocarcinoma arising on the scrotum of a 55-year-old man. Because of the extraordinary location and the presence of keratinizing squamous differentiation, distinction from a squamous cell carcinoma was particularly challenging. Close examination revealed the presence of a co-existing poroma, and immunohistochemistry revealed loss of YAP1 with diffuse nuclear expression of NUT in both the porocarcinoma and poroma components. This finding is particularly suggestive of a YAP1::NUTM1 fusion which has been reported to be highly specific for poroid neoplasms. Distinction of porocarcinoma from its mimics is important due to the frequent aggressive behavior of this neoplasm.

18F Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Findings in a Case of Metastatic Eccrine Porocarcinoma - An Extremely Rare Malignant Adnexal Tumor

Porocarcinoma is a rare malignant neoplasm of eccrine sweat glands representing 0.005 to 0.1% of all cutaneous tumors. As eccrine porocarcinoma carries a high risk of recurrence and metastases, early diagnosis and management are crucial to lower mortality rate. We present the case of porocarcinoma in a 69-years-old woman who underwent 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) for staging the disease. PET/CT showed metabolically active multiple cutaneous lesions and also picked up lymph nodal and distant metastases to lungs and breast accurately. PET/CT is useful for accurate staging of the disease and for treatment planning.

Intraabdominal dissemination of porocarcinoma; A case report

Introduction

Porocarcinoma is a rare malignancy of dermal sweat glands commonly diagnosed in the seventh decade of life. It frequently evolves from a de novo benign poroma. These tumors present as a mass/nodule, ulcer, papule, or wart. Difficult to differentiate from other cutaneous lesions. Intraperitoneal invasion is scantly reported in the literature.

Case presentation

The authors present a case of a fifty-year-old female patient with a rare cancer of the dermal sweat glands in an unusual location and infiltration into the abdominal cavity, leading to intraperitoneal seedlings.

Discussion

Tumors of the sweat gland are rare and difficult to diagnose, often misdiagnosed as granuloma, squamous cell tumors, or warts. Surgical excision and Mohs micrographic surgery are mainstay treatment modalities in the early stages. Our patient was managed elsewhere with a diagnosis of granuloma. She was referred with a recurrence of the abdominal lesion. An appropriate diagnosis of porocarcinoma was made while she had an extensive intraperitoneal invasion and seedlings. We postulate that the previous abdominal incision had disseminated porocarcinoma cells into the abdominal cavity, causing extensive intraperitoneal dissemination.

Conclusion

Because it is rare and difficult to diagnose, there is a considerable knowledge gap in the early accurate diagnosis and appropriate management of porocarcinoma. This causes a delay in establishing a diagnosis and profoundly impacts treatment outcomes.

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Eccrine porocarcinoma is a rare diagnosis of cutaneous malignancy.

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Early diagnosis and appropriate surgical treatment are the cornerstones of improving survival.

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It is often misdiagnosed as granuloma, squamous cell carcinoma, or viral warts.

Primary Eccrine Porocarcinoma of the Breast: A Case Report and Review of Literature

Eccrine porocarcinoma (EPC) is a rare cutaneous neoplasm, with less than 500 reported cases worldwide since it was first described in 1963. EPC tends to affect the elderly and most commonly affects the head and neck. The mainstay of EPC treatment is surgery, with lymphadenectomy in the case of nodal involvement or presence of unfavourable characteristics. No evidence exists to guide the use of adjuvant chemotherapy or radiation. EPC is prone to misdiagnosis given its multiple clinical and histopathological mimics, especially in uncommon sites of presentation such as the breast. Herein, we report the case of a 59-year-old woman who presented with a left breast skin lump. The biopsied specimen revealed an infiltrative carcinoma involving the dermis and epidermis with positive IHC staining for P63 and CK5/6 and negative staining for ER, PR, and HER2. The tumour was resected and diagnosed as EPC with atypical features as overlapping characteristics of squamous cell carcinoma (SCC) were detected on histopathological analysis. In our case, a simple mastectomy with broad margins and axillary lymph node dissection with adjuvant radiotherapy to a dose of 60 Gy failed to achieve loco-regional control with nodal recurrence occurring 4 months postsurgery-a testament to the aggressive course of this rare malignancy.

Porocarcinoma of the left arm: A report of a rare skin cancer case and literature review

Porocarcinoma is a rare type of skin cancer that develops from the intraepidermal ductal part of eccrine sweat glands. It can arise de novo or from poroma ground with high potential for locoregional metastatic spread, morbidity, and mortality. It mostly occurs in elderly patients.

Maligne Adnextumoren der Haut

Neoplasien der Hautadnexe (benigne oder maligne) können zum einen von den Talgdrüsen oder Haarfollikel ausgehen, zum andern auch eine Differenzierung Richtung ekkriner oder apokriner Schweißdrüsen zeigen. Auch Mischformen können vorkommen. Maligne Adnextumoren entstehen i. d. R. de novo. Dennoch ist auch die maligne Entartung einer vorbestehenden benignen Läsion möglich.

Maligne Adnextumoren der Haut sind im Vergleich zu anderen nicht-melanozytären Hauttumoren insgesamt eine eher seltene Entität. Jedoch zeigt sich, dass die Inzidenz von malignen Adnextumoren in den letzten Jahren zugenommen hat. Ähnlich wie bei anderen Hautkrebsarten sind auch bei malignen Adnextumoren das Alter, UV-Strahlung und Immunsuppression wichtige Risikofaktoren der Tumorgenese.

Da sich die Klinik sowohl von malignen als auch benignen Adnextumoren mit Ausnahme des Morbus Paget oftmals ähneln kann und wenig spezifisch ist, kommt der Histopathologie für die korrekte Diagnosestellung eine entscheidende Bedeutung zu.

Gemäß der Literatur sind die häufigsten malignen Adnextumore das Talgdrüsenkarzinom (23 %), der extramammäre Morbus Paget (19 %), das Hidradenokarzinom (15 %), das Porokarzinom (7 %) sowie das mikrozystische Adnexkarzinom (MAC) (5 %). Während manche Vertreter prognostisch mit einem Basalzellkarzinom vergleichbar sind (MAC), sind andere durchaus metastasierungsfähig vergleichbar den Plattenepithelkarzinomen (Talgdrüsenkarzinom, Porokarzinom). Andere Vertreter heben sich hier prognostisch besonders negativ ab mit hoher Lokalrezidivquote und Metastasierung, z. B. das Hidradenokarzinom.

Dieser Übersichtsartikel fokussiert sich auf diese 5 relativ häufigen Adnex-Malignome, die prognostisch auch die gegebene Streubreite wiedergeben und die Erfordernis einer den jeweiligen Besonderheiten geschuldeten klinischen Versorgung und Nachbetreuung unterstreichen.

Head and Neck Porocarcinoma: SEER Analysis of Epidemiology and Survival

Porocarcinoma is a rare malignant adnexal tumor. Little is known about the location of the disease in the head and neck. Our aim is to offer the largest analysis of demographic, pathological, and treatment patterns of head and neck porocarcinoma in comparison with other locations of the neoplasm from an epidemiologically representative cohort. Method: The Surveillance, Epidemiology, and End Results program of the National Cancer Institute was searched for all cases of porocarcinomas diagnosed between 2000 and 2018. This database is considered representative of the US population. Demographic, pathological, and treatment variables were compared between the head and neck and other regions. Overall and disease-specific survival was calculated and compared between groups. Results: 563 porocarcinomas were identified, with 172 in the head and neck. The mean age was 66.4 years. Males were more affected in the head and neck. Regional and distant invasion rates were low (2.9 and 2.3%, respectively). Local excision and Mohs surgery were the most frequent therapies. Five-year overall survival was 74.8%. Five-year disease-specific survival was 97%. Conclusions: Head and neck porocarcinoma affects more males than females. Regional or distant metastatic rates are low and overestimated in previous literature. Disease-specific mortality is low. Surgery remains the mainstay of treatment.

UV-induced local immunosuppression in the tumour microenvironment of eccrine porocarcinoma and poroma

Eccrine porocarcinoma (EPC) is a rare malignant adnexal tumour of the skin. Part of EPCs develop from their benign counterpart, poroma (EP), with chronic light exposure and immunosuppression hypothesized to play a role in the malignant transformation. However, the impact of chronic light exposure on the microenvironment of EPCs and EPs has not been investigated yet. Although the clinical relevance of tumour infiltrating lymphocytes (TILs) and tertiary lymphoid structures (TLSs) has been established in various tumours, their distribution and significance in EPCs and EPs is still poorly understood. We characterized the distribution of TILs and TLSs using CD3, CD4, CD8, CD20 immunohistochemistry in a cohort of 10 EPCs and 49 EPs. We then classified our samples using solar-elastosis grading, analyzing the influence of ultraviolet (UV) damage on TIL density. A negative correlation between UV damage and TIL density was observed (CD4 r = −0.286, p = 0.04. CD8 r = −0.305, p = 0.033). No significant difference in TIL density was found between EPCs and EPs. TLS was scarse with the presence rate 10% in EPCs and 8.3% in EPs. The results suggest that UV has an immunosuppressive effect on the microenvironment of EPCs and EPs.

Porocarcinoma: an epidemiological, clinical, and dermoscopic 20-year study

BACKGROUND

Porocarcinoma (PC) is a rare cutaneous adnexal tumor with a variable metastatic potential. Given the paucity of data, guidelines and specific recommendations for PC are not yet well-established. In this study, we evaluate the disease-specific characteristics and outcome of this rare and often underestimated tumor.

MATERIALS AND METHOD

A retrospective study of the epidemiological, clinical, and dermoscopic characteristics among cases of histopathologically diagnosed PC, collected from the database of two skin cancer clinics in Italy (Firenze, Pistoia) from 2000 to 2020, was conducted.

RESULTS

Among the 52 patients with 53 tumors, 31 were men (59.6%) and 21 were women (40.4%) with an age range of 49-96 years (median age 82 years). The most common locations were the head/neck region in men (34% in men vs. 17% in women) and the lower limb in women (17% in women vs. 9% in men). Forty-eight cases (91%) underwent local excision. Of these patients, two (4%) experienced local recurrence, and one (2%) developed a second PC on a different anatomical site 1 month after the primary tumor's excision. Lymph node metastases were present in three cases (6%). Two of them have been treated surgically with adjuvant radiotherapy (both are disease-free after a 2-year follow-up period), whereas the third case developed visceral metastases followed by PC-related death.

CONCLUSIONS

This study, with 52 patients with 53 tumors covering a follow-up period of more than 5 years, shows a less aggressive behavior of PC with 4% local recurrence, 6% nodal metastases, and 2% mortality.

Treatment of Malignant Adnexal Tumors of the Skin: A 12-Year Perspective

Malignant adnexal cancers of the skin—extremely rare neoplasms—are mostly reported as non-symptomatic, slow-growing nodules. These carcinomas occur mainly in the middle-aged (50–60 years of age); they are mostly localized on the upper part of the body and are locally aggressive, infiltrate surrounding tissue, and metastasize to regional lymph nodes. The patients’ outcomes depend on multiple prognostic factors, including the size of the primary tumor and its mitotic count. Surgical resection of the primary tumor with or without regional lymph nodes is the treatment method of choice; however, due to aggressive tumor behavior, perioperative treatment may be considered. The role and efficacy of radiotherapy in the treatment of skin adnexal malignancies are not yet fully defined. Some authors suggest that adjuvant radiotherapy may be considered in locally advanced and regional disease. The aim of this study was to evaluate treatment outcomes and assess the efficacy of combined therapy in patients with adnexal malignancies. Our analysis covered all cases of cutaneous adnexal tumor patients diagnosed and provided with multidisciplinary treatment with surgery and radiotherapy since the beginning of 2009.

Porocarcinoma - a review

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. It differentiates towards the intraepidermal spiral ducts in the eccrine gland, is more common in those over 60 years and often affects the head, neck and lower extremities. PC presents as a dome shaped papule, plaque or nodule growing over weeks to months. The exact incidence 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%. Given the lack of standardised protocols and risk profiles, further studies would help better the understanding of PC.

Molecular pathology of skin adnexal tumours

AIMS

Tumours of the cutaneous adnexa arise from, or differentiate towards, structures in normal skin such as hair follicles, sweat ducts/glands, sebaceous glands or a combination of these elements. This class of neoplasms includes benign tumours and highly aggressive carcinomas. Adnexal tumours often present as solitary sporadic lesions, but can herald the presence of an inherited tumour syndrome such as Muir-Torre syndrome, Cowden syndrome or CYLD cutaneous syndrome. In contrast to squamous cell carcinoma and basal cell carcinoma, molecular changes in adnexal neoplasia have been poorly characterised and there are few published reviews on the current state of knowledge.

METHODS AND RESULTS

We reviewed findings in peer-reviewed literature on molecular investigations of cutaneous adnexal tumours published to June 2021.

CONCLUSIONS

Recent discoveries have revealed diverse oncogenic drivers and tumour suppressor alterations in this class of tumours, implicating pathways including Ras/MAPK, PI3K, YAP/TAZ, beta-catenin and nuclear factor kappa B (NF-κB). These observations have identified novel markers, such as NUT for poroma and porocarcinoma and PLAG1 for mixed tumours. Here, we provide a comprehensive overview and update of the molecular findings associated with adnexal tumours of the skin.

Whole-exome sequencing in eccrine porocarcinoma indicates promising therapeutic strategies

Malignant sweat gland tumours are rare, with the most common form being Eccrine porocarcinoma (EP). To investigate the mutational landscape of EP, we performed whole-exome sequencing (WES) on 14 formalin-fixed paraffin-embedded samples of matched primary EP and healthy surrounding tissue. Mutational profiling revealed a high overall median mutation rate. This was attributed to signatures of mutational processes related to ultraviolet (UV) exposure, APOBEC enzyme dysregulation, and defective homologous double-strand break repair. All of these processes cause genomic instability and are implicated in carcinogenesis. Recurrent driving somatic alterations were detected in the EP candidate drivers TP53, FAT2, CACNA1S, and KMT2D. The analyses also identified copy number alterations and recurrent gains and losses in several chromosomal regions including that containing BRCA2, as well as deleterious alterations in multiple HRR components. In accordance with this reduced or even a complete loss of BRCA2 protein expression was detected in 50% of the investigated EP tumours. Our results implicate crucial oncogenic driver pathways and suggest that defective homologous double-strand break repair and the p53 pathway are involved in EP aetiology. Targeting of the p53 axis and PARP inhibition, and/or immunotherapy may represent promising treatment strategies.

Primary Eccrine Porocarcinoma of the Thumb With Metastasis: A Rare Case Report and Literature Review

ABSTRACT

Eccrine porocarcinoma (EPC) is a rare malignant sweat gland tumor that accounts for approximately 0.005% of all cutaneous carcinomas. It favors the lower extremities. Only 3% of EPCs are on the hand, and only 6 cases occurring specifically on fingers have been previously documented. However, we met a patient with EPC presenting the primary lesion on the left thumb and an extensive cutaneous metastasis on the left forearm. Pathologic findings of axillary lymph nodes confirmed lymphatic metastasis.