Apocrine-eccrine carcinomas: molecular and immunohistochemical analyses

A rare case of hidradenocarcinoma with anaplastic and invasive features arising from a nodulocystic hidradenoma

A 91-year-old man presented with a cutaneous left abdominal mass. The mass was longstanding (over 5 years) and slow-growing. Examination revealed a violaceous, multinodular, and exophytic non-tender mass surrounded by patchy erythema. Excisional biopsy was performed and revealed a nodular and cystic dermal proliferation of predominately basaloid cells with focal duct formation, surrounded by prominent hyalinized stroma. The superficial portion of the mass was identified as a nodulocystic hidradenoma. Along the deep aspect and in association with the benign hidradenoma, sheets of markedly atypical epithelioid cells invaded the surrounding tissue, consistent with malignant transformation. Perineural and lymphovascular invasion were seen among areas with anaplastic features. This case supports that some hidradenocarcinoma originates from benign counterparts, and as such, ample sampling is required to definitively exclude a more sinister diagnosis. Diagnostic, prognostic, histopathological, and molecular characteristics, and current knowledge limitations are briefly discussed.

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.

Molecular Profiling of Syringocystadenocarcinoma Papilliferum Reveals RAS-Activating Mutations

CONTEXT.—

Syringocystadenocarcinoma papilliferum (SCACP) is a rare adnexal carcinoma and the malignant counterpart of syringocystadenoma papilliferum (SCAP), which is commonly located on the head and neck and may arise in association with a nevus sebaceus. RAS mutations have been identified in both SCAP and nevus sebaceus.

OBJECTIVE.—

To evaluate the clinicopathologic and molecular features of SCACPs, which have not been previously explored.

DESIGN.—

We obtained 11 SCACPs from 6 institutions and reviewed the clinicopathologic features. We also performed molecular profiling using next-generation sequencing.

RESULTS.—

The cohort comprised 6 women and 5 men with ages ranging from 29 to 96 years (mean, 73.6 years). The neoplasms occurred on the head and neck (n = 8; 73%) and extremities (n = 3; 27%). Three tumors possibly arose in a nevus sebaceus. A total of 4 cases showed at least carcinoma in situ (adenocarcinoma, n = 3; squamous cell carcinoma [SCC], n = 1), and 7 cases were invasive (SCC, n = 5; mixed adenocarcinoma + SCC, n = 2). A total of 8 of 11 cases (73%) had hot spot mutations consisting of HRAS (n = 4), KRAS (n = 1), BRAF (n = 1), TP53 (n = 4), ATM (n = 2), FLT3 (n = 1), CDKN2A (n = 1), and PTEN (n = 1). All 4 cases with HRAS mutations occurred on the head and neck, whereas the KRAS mutation occurred on the extremity.

CONCLUSIONS.—

RAS-activating mutations were detected in 50% of the cases, of which most (80%) involved HRAS and occurred on the head and neck, which shows overlapping features with SCAP, supporting that a subset may arise as a result of malignant transformation and likely an early oncogenic event.

Sweat Gland Tumors Arising on Acral Sites: A Molecular Survey

Recurrent oncogenic drivers have been identified in a variety of sweat gland tumors. Recently, integration of human papillomavirus type 42 (HPV42) has been reported in digital papillary adenocarcinoma (DPA). The main objectives of the present study were (i) to provide an overview of the prevalence of previously identified oncogenic drivers in acral sweat gland tumors and (ii) to genetically characterize tumors in which no recurrent genetic alteration has been identified yet. Cases of acral sweat gland tumors were identified from the database of the French network CARADERM. After histologic review, the presence of previously identified genetic alterations was investigated in the entire cohort (n=79) using a combination of immunohistochemistry and targeted DNA and RNA sequencing. Tumor entities with no recurrent genetic alterations were submitted to whole-transcriptome sequencing. CRTC1::MAML2 fusion was identified in cases of hidradenoma and hidradenocarcinoma (n=9/12 and n=9/12). A p.V600E mutation of BRAF was observed in all cases of tubular adenoma (n=4). YAP1:MAML2 and YAP1::NUTM1 fusions were observed in poroid tumors (n=15/25). ETV6::NTRK3 and TRPS1::PLAG1 fusion transcripts were identified in secretory carcinoma (n=1/1) and cutaneous mixed tumors (n=3/4), respectively. The HPV42 genome was detected in most cases of DPA (n=10/11) and in 1 adnexal adenocarcinoma not otherwise specified. Finally, whole-transcriptome analysis revealed BRD3::NUTM1 or NSD3::NUTM1 fusions in 2 cases of NUT adnexal carcinoma and NCOA4::RET and CCDC6::RET fusion transcripts in 2 cystadenoma/hidrocystoma-like tumors. Our study confirms distinctive cytogenetic abnormalities in a wide number of acral adnexal neoplasms and supports the use of molecular analysis as a valuable aid in the diagnosis of these rare and often difficult to diagnose group of neoplasms.

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.

Low-Grade Hidradenocarcinoma of the Foot With Metastasis to a Lymph Node

ABSTRACT

Hidradenocarcinoma (HAC) is a rare adnexal tumor associated with the potential for locoregional recurrence and systemic metastasis. The clinical appearance of HAC is nonspecific, frequently presenting as a solitary firm subcutaneous nodule or plaque on the head and neck region or distal extremities. These tumors show histomorphologic heterogeneity, as they can be low and high grade. Distinguishing HAC from hidradenoma, especially the low-grade variant of HAC, can be challenging as both tumors can show histologic overlapping features. In this article, we describe a case of a 33-year-old patient presenting with a low-grade HAC of the plantar foot who was subsequently found to have lymph node metastasis.

An Atypical Rash on the Chest

A 71-year-old man presented with a rapidly progressing rash and swelling of the left side of the chest wall. What is your diagnosis?

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.

Breast carcinoma or sweat gland carcinoma? A report of two cases and a comparison with the literature

Primary apocrine carcinoma of the sweat gland is a neoplasm with a very low incidence that may represent a clinical and histological diagnostic challenge, as well as for adequate local, adjuvant, and advanced disease management. The average age of patients is around 67 years with no gender preference. This cancer develops primarily at the axillary and scalp levels and is clinically characterized by slow growth, but can progress aggressively with local, nodal, and metastatic involvement (primarily lung, liver, and bone). The recommended management, once the histology is established, consists of a wide local resection with a clear margin of 1 to 2 cm and regional lymphadenectomy if clinically positive nodes are detected. The adjuvant treatment (radiotherapy or chemotherapy) and for the advanced disease is not established. We report here the cases of two female patients initially diagnosed with breast cancer who were finally diagnosed with apocrine carcinoma of the sweat gland.

Unusual Presentations of Eccrine Porocarcinomas

Eccrine porocarcinomas (EPCs) are rare tumours, albeit the most common malignant adnexal tumours of the skin. They can present with very heterogeneous clinical and dermoscopic features, rendering diagnosis limited to histopathological examination alone. We share 2 cases of EPCs, one of which arose in a patient with a prior diagnosis of cutaneous squamous cell carcinoma (SCC) and another whose EPC was likely a malignant transformation of an existing poroma. An occurrence of porocarcinoma after the diagnosis of SCC may suggest the possibility of unknown risk factors for both. Positivity to androgen, oestrogen, and epidermal growth factor receptors was seen in a proportion of porocarcinomas, and this may prompt further research on combination therapy between conventional treatment modalities with hormone receptor antagonists. Malignant change of a poroma may be a more common phenomenon than we would expect based on the current literature.

High tumour mutational burden and EGFR/MAPK pathway activation are therapeutic targets in metastatic porocarcinoma

BACKGROUND

Eccrine porocarcinoma (EPC) is a rare skin cancer arising from the eccrine sweat glands. Due to the lack of effective therapies, metastasis is associated with a high mortality rate.

OBJECTIVES

To investigate the drivers of EPC progression.

METHODS

We carried out genomic and transcriptomic profiling of metastatic EPC (mEPC), validation of the observed alterations in an EPC patient-derived cell line, confirmation of relevant observations in a large patient cohort of 30 tumour tissues, and successful treatment of a patient with mEPC under the identified treatment regimens.

RESULTS

mEPC was characterized by a high tumour mutational burden (TMB) with an ultraviolet signature, widespread copy number alterations and gene expression changes that affected cancer-relevant cellular processes such as cell cycle regulation and proliferation, including a pathogenic TP53 (tumour protein 53) mutation, a copy number deletion in the CDKN2A (cyclin dependent kinase inhibitor 2A) region and a CTNND1/PAK1 [catenin delta 1/p21 (RAC1) activated kinase 1] gene fusion. The overexpression of EGFR (epidermal growth factor receptor), PAK1 and MAP2K1 (mitogen-activated protein kinase kinase 1; also known as MEK1) genes translated into strong protein expression and respective pathway activation in the tumour tissue. Furthermore, a patient-derived cell line was sensitive to EGFR and MEK inhibition, confirming the functional relevance of the pathway activation. Immunohistochemistry analyses in a large patient cohort showed the relevance of the observed changes to the pathogenesis of EPC. Our results indicate that mEPC should respond to immune or kinase inhibitor therapy. Indeed, the advanced disease of our index patient was controlled by EGFR-directed therapy and immune checkpoint inhibition for more than 2 years.

CONCLUSIONS

Molecular profiling demonstrated high TMB and EGFR/MAPK pathway activation to be novel therapeutic targets in mEPC.

Update on Molecular Genetic Alterations of Cutaneous Adnexal Neoplasms

Cutaneous adnexal tumors recapitulate follicular, sweat gland, and/or sebaceous epithelia, and range from benign tumors to aggressive carcinomas. Adnexal tumors can be hallmarks for inherited tumor syndromes. Oncogenic drivers of adnexal neoplasms modulate intracellular pathways including mitogen-activated protein kinase, phosphoinositide-3-kinase, Wnt/β-catenin, Hedgehog, nuclear factor κB, and Hippo intracellular signaling pathways, representing potential therapeutic targets. Malignant progression can be associated with tumor suppressor loss, especially TP53. Molecular alterations drive expression of specific diagnostic markers, such as CDX2 and LEF1 in pilomatricomas/pilomatrical carcinomas, and NUT in poromas/porocarcinomas. In these ways, improved understanding of molecular alterations promises to advance diagnostic, prognostic, and therapeutic possibilities for adnexal tumors.

Hidradenocarcinoma of the Abdominal Wall Treated With Wide Surgical Excision and Adjuvant Radiotherapy

Hidradenocarcinomas are rare malignant sweat gland tumors that typically arise in the head and neck area. To the best of our knowledge, this is the only reported instance of hidradenocarcinoma of the abdominal wall as well as the first case arising from a region of prior trauma. A 72-year-old female presented with a left abdominal wall lesion, which she had first noticed after an injury to the area. Initially, the lesion remained stable in size, after which it became mildly pruritic, progressive in size, and expressive of a clear, non-odorous discharge. Imaging demonstrated a heterogeneous cystic density. Surgical pathology revealed a malignant dermal adnexal neoplasm composed of pleomorphic polygonal cells and focal intracytoplasmic lumina lined by eosinophilic cuticles, as well as areas of ductal differentiation, apocrine differentiation, and mucinous metaplasia. Surgical excision of the mass was performed, followed by adjuvant external beam radiotherapy (EBRT). The patient had no long-term toxicities or clinical evidence of local disease recurrence as of one year post-surgery and six months post-EBRT. Early diagnosis and treatment are essential to improving outcomes in patients with hidradenocarcinomas. Frequent follow-up is equally important, as these tumors have high recurrence rates.

Poroid adnexal skin tumors with YAP1 fusions exhibit similar histopathologic features: A series of six YAP1-rearranged adnexal skin tumors

BACKGROUND

Adnexal skin tumors are diagnostically challenging with few known molecular signatures. Recently, however, YAP1-MAML2 and YAP1-NUTM1 fusions were identified in poroid adnexal skin tumors.

METHODS

Herein, we subjected eight poroid adnexal skin tumors (three poromas and five porocarcinomas) to fusion gene analysis by whole transcriptome sequencing and next-generation DNA sequencing analysis.

RESULTS

YAP1 fusions were identified in six cases. YAP1-NUTM1 fusions were identified in two poromas and three porocarcinomas. A single case of porocarcinoma harbored a YAP1-MAML2 fusion. Two cases were negative for gene fusion. All cases that harbored YAP1-NUTM1 fusions showed nuclear protein in testis (NUT) expression by immunohistochemistry, with NUT being negative in the YAP1-MAML2-positive case. In this case series, we provide a detailed histopathologic description of six YAP1-fused poroid skin tumors, which we show harbor reproducible histopathologic features, to include broad, bulbous tumor tongues with admixtures of basaloid, poroid cells punctuated by squamatized cuticles and ductules, with uniform tumor nuclei featuring frequent grooves and pseudonuclear inclusions.

CONCLUSIONS

Awareness of the characteristic histopathologic features of YAP1-fused poroid adnexal skin tumor is a step toward a more reproducible classification of adnexal skin tumors as well as a step toward targeted therapy for metastatic and/or unresectable examples of this poroid group of neoplasms.

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

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

Central Nervous System-Invading Eccrine Gland Carcinoma: A Clinicopathologic Case Series and Literature Review

BACKGROUND

Eccrine carcinoma involvement of the central nervous system (CNS) is exceedingly rare. The prognosis and response to treatment of this pathology remain poorly characterized.

METHODS

A retrospective case series and literature review were conducted.

RESULTS

CNS-invading eccrine carcinoma was diagnosed in 3 patients (2 male and 1 female; age range, 60-79 years), including 2 cases of brain metastases and 1 case of brain-invading skull metastasis with subsequent spinal metastasis. The interval from primary tumor to CNS invasion was 18-51 months. All patients received multimodal therapy following diagnosis of CNS involvement. One patient who harbored a NOTCH1 mutation demonstrated a durable oncologic response after treatment with the immune checkpoint inhibitor pembrolizumab and lived 39 months after CNS invasion. The other 2 patients were discharged to hospice care within 1 month after the diagnosis of eccrine carcinoma brain metastasis. Including this case series, 23 cases of eccrine carcinoma invasion or metastasis to the CNS have been reported, with survival after diagnosis of CNS involvement ranging from a few weeks to 4 years.

CONCLUSIONS

We present 3 cases of eccrine carcinoma metastatic to the CNS, including the first reported case to our knowledge of eccrine carcinoma treated with immunotherapy. This case, harboring a NOTCH1 mutation, demonstrated the longest durable oncologic response reported in this rare disease. Genomic and molecular testing may play increasingly important roles in the evaluation of these metastases.

Primary Cutaneous Adenomyoepithelioma Ex Spiradenoma With Malignant Histologic Features, Epithelial-Myoepithelial Carcinoma Type: A First Case Report With Molecular Studies

Adenomyoepithelioma is an extremely rare primary cutaneous neoplasm. Although there is ample evidence on the existence of malignant adenomyoepithelioma in the breast, a malignant counterpart in the skin has not been documented. We report a primary cutaneous adenomyoepithelioma (pcAME) with malignant features arising from a spiradenoma in a 39-year-old female patient. The tumor was solid-cystic in appearance and entirely located in the subcutaneous tissue. Histologically, the tumor displayed foci of adenomatous changes and adenomyoepitheliomatous hyperplasia adjacent to a minute spiradenoma. Gradual increase of architectural complexity, cytologic atypia, mitotic activity, and infiltrative growth were observed in a significant portion of the neoplasm, indicative of transformation to adenomyoepithelioma and subsequently low- to high-grade salivary-type epithelial-myoepithelial carcinoma (EMCA). The intimate dual populations of ductal and myoepithelial cells were highlighted by a panel of immunohistochemical stains in all different components of the tumor. Molecular studies revealed a PIKCA3 mutation, a genetic aberration that has been documented in EMCA, particularly of breast origin. The current case documents for the first time a pcAME with malignant features arising from a spiradenoma and suggests adenomyoepithelioma ex spiradenoma as a possible tumorigenesis pathway of this rare cutaneous tumor.

A clinical, pathological and immunohistochemical series of 9 cases of primary cutaneous apocrine carcinomas of the head and neck

BACKGROUND/OBJECTIVES

Primary cutaneous apocrine carcinoma is a rare malignant adnexal skin tumour that can recur locally, spread to regional lymph nodes and metastatize to visceral organs. Wide dissemination and death from disease are much less common. The axilla is the most common site of presentation. It is infrequently reported in the head and neck region.

METHODS

All cases diagnosed as primary cutaneous apocrine carcinoma of the head and neck were retrospectively collected from the archives of the Division of Pathological Anatomy, University of Florence from 1996 to 2016. There was no history or clinical evidence of breast cancer. Clinical data and follow-up were collected by the clinicians.

RESULTS

Nine cases were found, with a mean age of 76 years, ranging in size between 0.3 and 3.5 cm. Clinically, they were frequently mistaken for basal cell carcinomas. Histopathologically, all the tumours showed decapitation secretion, a tubular, solid or mixed (tubulo-papillary and solid-tubular) growth pattern and were predominantly classified as grade 2 tumours. GCDFP-15 and hormone receptors were variably expressed. HER2 and podoplanin were negative in all cases. In one case, spreading to regional lymph nodes was observed. No cases were associated with death due to the disease.

CONCLUSION

As immunohistochemical analysis lacks specificity in distinguishing primary cutaneous apocrine carcinoma from a cutaneous metastasis of breast carcinoma, detailed clinical history, breast examination, adequate treatment and follow-up are necessary to confirm a diagnosis of primary cutaneous apocrine carcinoma.

Oral Capecitabine Achieves Response in Metastatic Eccrine Carcinoma

The low prevalence rate and limited literature on eccrine carcinoma (EC) pose a challenge to properly diagnosing and treating this rare malignancy. EC lesions tend to present similarly to other cutaneous neoplasms and dermatitis-like conditions. Efficacious treatment guidelines have not been established for patients diagnosed with EC, and few treatment regimens have demonstrated clinical benefit. Due to the high metastatic potential of EC, recognizing the clinical presentation, properly diagnosing, and utilizing beneficial treatment options are important for managing this disease. We report a case of a 66-year-old female who presented with lesions that her primary care provider misdiagnosed as basal cell carcinoma. The disease responded poorly to taxane- and platinum-based chemotherapies as well as an isolated limb perfusion of an alkylating agent. However, continuous dosing of oral capecitabine achieved an 18-month period of progression free survival (PFS) and ameliorated quality of life. We wish to highlight this rare disease and discuss presentation, diagnosis, and management as it is most often misdiagnosed leading to advanced metastatic disease when patients present to the oncologist. In addition, it is crucial to study and report potentially efficacious regimens considering the lack of clinical trials in this disease.

Targeted molecular profiling reveals genetic heterogeneity of poromas and porocarcinomas

The genetic landscape of rare benign tumours and their malignant counterparts is still largely unexplored. While recent work showed that mutant HRAS is present in subsets of poromas and porocarcinomas, a more comprehensive genetic view on these rare adnexal neoplasms is lacking. Using high-coverage next generation sequencing, we investigated the mutational profile of 50 cancer-related genes in 12 cases (six poromas and six porocarcinomas). Non-synonymous mutations were found in two-thirds of both poromas and porocarcinomas. Hotspot HRAS mutations were identified in two poromas (p.G13R and p.Q61R) and one porocarcinoma (p.G13C). While in poromas only few cases showed single mutated genes, porocarcinomas showed greater genetic heterogeneity with up to six mutated genes per case. Recurrent TP53 mutations were found in all porocarcinomas that harboured mutated genes. Non-recurrent mutations in porocarcinomas were found in several additional tumour suppressors (RB1, APC, CDKN2A, and PTEN), and genes implicated in PI3K-AKT and MAPK signalling pathways (ABL1, PDGFRA, PIK3CA, HRAS, and RET). UV-associated mutations were found in TP53, APC, CDKN2A, PTEN, and RET. In conclusion, our study confirms and extends the spectrum of genetic lesions in poromas and porocarcinomas. While poromas exhibited only few mutations, which did not involve TP53, the majority of porocarcinomas harboured UV-mediated mutations in TP53 with some of these cases showing considerable genetic heterogeneity that may be clinically exploitable.

[Atypical course of an apocrine sweat gland carcinoma of the axilla : A very rare malignant tumor and its interdisciplinary treatment]

We report on an atypical clinical course of a patient with the very rare diagnosis of an apocrine sweat gland carcinoma with lymphatic metastasis, a single metachronous distant metastasis and a now reached survival time of more than 4 years and give a review about the current literature. Only a very small number of cases have been described. The recommendations for diagnostics and treatment of this tumor, therefore, are not based on prospective randomized studies but upon case reports and on new immunohistochemical and genetic markers.

[Hidradenocarcinoma of the heel associated with inguinal metastases]

BACKGROUND

Hidradenocarcinoma is a rare malignant tumour involving the sweat glands. It classically arises de novo, only rarely resulting from pre-existing hidradenoma. The literature contains few reports of lymph node metastasis in this tumour. We report a case of a patient with hidradenocarcinoma of the heel associated with inguinal node metastases.

PATIENTS AND METHODS

We report the case of a 64-year-old patient with a history of chronic smoking, who in the last two years developed a painless nodule in his right heel, with no prior injury, and which gradually increased in size to become an ulcerated tumour. Physical examination revealed a rounded tumour mass, ulcerated in the centre, and associated with multiple inguinal adenopathies. Histological and immunohistochemical examination was suggestive of hidradenocarcinoma. The patient had undergone extensive local excision with inguinal lymphadenectomy. Histological examination showed infiltration of lymph nodes by the tumour with capsular rupture. Radiotherapy was subsequently given. The outcome was good without recurrence after 34 months of follow-up.

DISCUSSION

Hidradenocarcinoma is a rare malignant tumour. Diagnosis is based on histological and immunohistochemical examination. However, hidradenocarcinoma may on occasion be difficult to differentiate from hidradenoma, a benign tumour, hence the interest of complete surgical resection with safety margins even in the absence of cytological malignancy. Local recurrences are common. The occurrence of lymph node metastasis during hidradenocarcinoma has been described only rarely in the literature. Such metastases usually occur after tumour resection. The specific features of our case are the rarity of lymph node metastases in hidradenocarcinoma coupled with the fact that these metastases were discovered upon diagnosis of the primary tumour.

Aggressive digital papillary adenocarcinoma: A clinicopathological study of 19 cases

BACKGROUND

Aggressive digital papillary adenocarcinomas (ADPA) are malignant tumors of sweat glands having recurrence/metastatic potential.

OBJECTIVE

We sought to describe the clinical/histopathological characteristics of a series of ADPA.

METHODS

This is a retrospective case series of 19 ADPA.

RESULTS

The tumors occurred in 17 men and 2 women (mean age: 47 years). They involved digits (15), big toe (3), and palm (1), and measured from 3 to 30 mm. They were mostly solid and cystic, with papillary projections and tubular structures. Atypia was mostly mild to moderate. Tumors tested positive for p63, keratin 7, keratin 77 (eccrine duct-specific), PHLDA1, and epithelial membrane antigen in most cases, and for carcinoembryonic antigen, smooth muscle actin, S100 protein, estrogen, progesterone, and androgen receptors in 50%. Mean Ki67 proliferation index was 15%. Local recurrence was observed in 4 cases. One patient had axillary lymph node metastasis. Histopathologic parameters were not predictive of evolution. Conservative surgical treatment, performed in 7 of 19 cases, did not result in more recurrences than amputation.

LIMITATIONS

The study was retrospective and the number of cases is small.

CONCLUSION

ADPA are histologically variable, but papillary projections are always present. Keratin 77 expression suggests an eccrine origin. P63 is helpful to exclude metastasis. Conservative surgery may be sufficient in some cases.

Apocrine Adenocarcinoma of the Vulva: A Case Report and Review of the Literature

Primary vulvar adenocarcinomas are very rare. We describe the rare case of primary vulvar apocrine adenocarcinoma, a histologically rare subtype of vulvar adenocarcinoma. A 57-year-old Japanese woman presented with an enlarging vulvar mass. A dark-red, hemorrhagic, ulcerated tumor was on the right side of the anterior labial commissure measuring approximately 3.5 × 3.5 cm. Preoperative biopsy showed poorly differentiated carcinoma with partial differentiation to adenocarcinoma. Systemic examination revealed lymph node metastases in both inguinal regions and no other primary source. We performed radical vulvectomy and bilateral inguinal and pelvic lymphadenectomy. Histopathologic diagnosis was apocrine adenocarcinoma of the vulva with inguinal lymph node metastases, pT1bN2bM0. Surgical margins were negative. The patient received no adjuvant chemotherapy or radiation. Inguinal lymph node recurrence occurred after six months. Reresection and adjuvant tomotherapy were performed. After a further 12 months of observation, no rerecurrence was observed. The patient is now on follow-up.

Malignant chondroid syringoma of the pinna

Chondroid syringoma (CS) represents the cutaneous counterpart of mixed tumor (pleomorphic adenoma) of salivary glands. The malignant counterpart of CS, termed as "malignant CS" is a malignant eccrine neoplasm which lacks distinctive clinical features, often delaying initial diagnosis. Unlike its benign counterpart which often localizes in the head and neck region, malignant CS most often encountered in the trunk and the extremities. We report a rare case of an aggressive malignant CS of the left pinna with cervical lymph node metastasis. Our patient, to the best of our knowledge, possibly is the first case of malignant CS of the pinna and the fourth to arise in the head and neck region. The diagnostic challenges with an added emphasis on the role of positron emission tomography-computed tomography in aiding the management of this rare tumor are discussed.

Predictive Biomarker Profiling of > 6000 Breast Cancer Patients Shows Heterogeneity in TNBC, With Treatment Implications

BACKGROUND

Triple-negative breast cancer (TNBC) is an aggressive disease without established targeted treatment options for patients with metastatic disease. This study was undertaken to evaluate potentially actionable biomarkers in a large cohort of TNBC and compare them with non-TNBCs.

MATERIALS AND METHODS

We evaluated 6341 (2111 TNBC and 4230 non-TNBC) breast cancer samples at a central laboratory for biomarkers of potential drug response across multiple platforms, including gene sequencing, protein expression, and gene copy number.

RESULTS

TNBC expresses androgen receptor (AR) in a significantly (P < .05) lower percentage of cases (17%) than hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-positive breast carcinomas (59% and 79%, respectively), and gene comutations were differentially associated with AR-positive versus AR-negative cases. Higher AR expression levels in TNBC predicted for lower Ki-67 levels. Seventy percent of TNBC harbored a phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA), v-akt murine thymoma viral oncogene homolog 1 (AKT1), or phosophatase and tensin homolog (PTEN) aberration. TNBC patients had a significantly lower PIK3CA mutation rate (13%) than all other subtypes (P < .05) and a higher tumor protein p53 (TP53) mutation rate (64%) than the estrogen receptor (ER)-positive cases (approximately 30%; P < .05). Topoisomerase 2 (TOP2A) amplification was observed in 1.3% of TNBC and in 1.6% of HER2-negative, HR-positive cancers; in contrast, HER2-positive, HR-negative or HR-positive cancers exhibited TOP2A amplification in 19% and 40% of cases, respectively (P <.05).

CONCLUSION

Multi-platform molecular profiling identifies subgroups of TNBC with different biomarker profiles, suggesting numerous potentially targetable alterations in TNBC. TNBC is further characterized by different gene mutations and proliferative activity relative to AR expression, highlighting a need for comprehensive pathologic examination with potential to develop different, individualized treatment options.

Current management approach to hidradenocarcinoma: a comprehensive review of the literature

Hidradenocarcinoma is a rare malignant adnexal tumour which arises from the intradermal duct of eccrine sweat glands. The head and neck are the most common sites of hidradenocarcinoma, but rarely it can occur on the extremities. As it is an aggressive tumour, regional lymph nodes and distant viscera are the most common sites of metastasis. Diagnosis is confirmed by histopathology and immunohistochemistry. Hidradenocarcinoma should be differentiated from benign and malignant adnexal tumours. Being an aggressive and rare tumour, no uniform treatment guidelines have been documented so far for metastatic hidradenocarcinoma. Wide local excision is the mainstay of the treatment, but because of high local recurrence, radiotherapy in a dose of 50Gy–70Gy and/or 5-fluorouracil and capecitabine-based combination chemotherapy may be given to further improve local control. Other treatment strategies are targeted therapies like trastuzumab, EGFR inhibitors, PI3K/Akt/mTOR pathway inhibitors, hormonal agents like antiandrogens, electrochemotherapy, or clinical trials.

Primary apocrine sweat gland carcinomas of the axilla: a report of two cases and a review of the literature

Primary apocrine sweat gland carcinoma (PASGC) is an extremely rare malignancy with a relatively favorable prognosis. PASGC is often suspected to be a benign disease during an initial clinical examination, which leads to inadequate initial treatment and extensive metastasis. Owing to the limited number of reports on PASGC, its diagnostic criteria and treatment guidelines have not yet been established. The only known curative therapy for localized PASGC is wide local excision. In the present report, we describe two cases of PASGC with locally aggressive disease that arose in the axilla and review the literature about its clinicopathological features, diagnosis, and treatment. Based on the findings of the current report, we suggest that a sentinel lymph node biopsy and adjuvant anti-estrogen therapy should be included in the management of PASGC.

Bufalin attenuates the stage and metastatic potential of hepatocellular carcinoma in nude mice

Background

Advanced hepatocellular carcinoma (HCC) patients undergo significant tumor growth and metastasis. Here, we investigated bufalin for treating HCC, which exhibits anti-tumor activities in many tumor cell lines.

Method

In our experiment, HCCLM3-R cells were injected into nude mice to form subcutaneous human HCC tumors that were implanted into the liver to establish orthotopic transplantation tumor models. Bufalin was injected intraperitoneally at 1 or 1.5 mg/kg. LY294002 (100 mg/kg), a potent inhibitor of Akt which reduced the levels of pAkt in HCCLM3 cell lines, was injected intraperitoneally into one group thrice weekly. The control was injected with an equal volume of saline. Morphological alterations were evaluated in the liver and lung by stereomicroscopy, the apoptotic rate was measured by TUNEL staining, and expression of AKT/GSK3β/β-catenin/E-cadherin signaling pathway-related proteins was detected by immunohistochemistry (IHC) and western blot analysis.

Results

These results suggested that the sizes and qualities of orthotopic transplanted tumors as well as pulmonary metastasis decreased markedly at the highest bufalin dose compared with that in the control. Orthotopic transplanted tumor tissues were necrotic in bufalin-treated groups and the apoptotic cell number was markedly higher at the highest bufalin dose compared with that in the control. Certain changes of expression of AKT/GSK3β/β-catenin/E-cadherin signaling pathway-related proteins were in tumor tissues, which were related to the bufalin dose. Similar results were observed in the LY294002-treated group.

Conclusion

Based on the above, one can draw conclusions that bufalin has significant anti-tumor activities and reduces the metastatic potential in an orthotopic transplantation tumor model of human HCC. Inhibition of AKT/GSK3β/β-catenin/E-cadherin signaling pathways by bufalin may show therapeutic effects in advanced HCC patients.

Cutaneous and mammary apocrine carcinomas have different immunoprofiles

Often the distinction of cutaneous apocrine carcinoma from metastatic mammary apocrine carcinoma to the skin can be a diagnostic dilemma because both tumors share similar histologic features and have overlapping immunohistochemical profile. We compared the expression of adipophilin, cytokeratin 5/6, p63, GATA3, mammaglobin, androgen receptor, estrogen receptor, progesterone receptor, and HER2 by immunohistochemistry in 14 cutaneous apocrine carcinomas (11 primary tumors, 3 metastases) and 26 primary apocrine carcinomas of the breast. Whereas focal adipophilin staining was seen in 36% (5/14) of cutaneous apocrine carcinoma, strong and diffuse adipophilin staining was seen in 88% (22/25) of mammary apocrine carcinoma (P = .0013). Differences in estrogen receptor and progesterone receptor expression were also statistically significant (P = .018 and .043). Androgen receptor was strongly positive in all cutaneous and mammary cases. Although there was no significant difference in the frequency of expression of cytokeratin 5/6, p63, HER2, GATA3, and mammaglobin in cutaneous apocrine carcinoma versus mammary apocrine carcinoma, strong and diffuse cytokeratin 5/6 and/or mammaglobin expression were seen only in cutaneous apocrine carcinoma. In conclusion, cutaneous apocrine carcinoma is likely adipophilin- ER+ PR+/- HER2- and can exhibit strong and diffuse cytokeratin 5/6 and/or mammaglobin expression. On the contrary, a mammary apocrine carcinoma is likely adipophilin+ ER- PR- and often exhibit 3+ HER2 with corresponding HER2 gene amplification. A panel of adipophilin, ER, PR, HER2, cytokeratin 5/6, and mammaglobin may be helpful in distinguishing cutaneous apocrine carcinoma from mammary apocrine carcinoma.

Vulvar Adnexal Lesions: A 32-Year, Single-Institution Review From Massachusetts General Hospital

Context.—Because the skin and modified mucosal surfaces of the vulvar region contain dense apocrine glands and anogenital mammary-like glands, in addition to eccrine glands and folliculosebaceous units, benign as well as malignant lesions derived from these adnexal structures are, not surprisingly, found in the vulva. However, their incidence occurring in the vulva has not been reported, to our knowledge.

Objective.—To determine the incidence of various vulvar adnexal lesions.

Design.—We performed a retrospective review (1978–2010) of the cases at our institution.

Results.—A total of 189 vulvar adnexal lesions were identified. Most of these lesions were benign (133 of 189; 70%), with hidradenoma papilliferum being the most common, followed by syringoma and various types of cysts. Rare cases of tubular adenoma, poroma, spiradenoma, hidradenoma, cylindroma, sebaceoma, and trichoepithelioma were identified. Malignant adnexal neoplasms comprised the remaining 30% (56 of 189) of the cases. Extramammary Paget disease was the most common (49 of 56), and 29% (14 of 49) demonstrated an invasive component. Rare cases of basal cell carcinoma, sebaceous carcinoma, apocrine carcinoma, adenoid cystic carcinoma, and spiradenocarcinoma were identified.

Conclusions.—In this retrospective review, we identified several benign entities that have not been previously reported on the vulva, namely pilomatricoma, poroma, spiradenoma, and sebaceoma. Hidradenoma papilliferum and extramammary Paget disease were the most common benign and malignant adnexal neoplasms, respectively. The spectrum of various vulvar adnexal lesions appears to reflect the frequency of the underlying glandular elements.