Clear-cell porocarcinoma: another cutaneous marker of diabetes mellitus

Clear Cell Proliferations of the Skin: A Histopathologic Review

ABSTRACT

Cutaneous clear cell proliferations encompass a heterogenous group of several primary cutaneous neoplasms and metastatic tumors with different histogenesis. Many of these clear cell proliferations may seem strikingly similar under the microscope resulting in challenging diagnosis. In many of these clear cell lesions, the reason for the clear or pale appearance of proliferating cells is unknown, whereas in other ones, this clear cell appearance is due to intracytoplasmic accumulation of glycogen, mucin, or lipid. Artifacts of tissue processing and degenerative phenomenon may also be responsible for the clear cell appearance of proliferating cells. Awareness of the histopathologic findings as well as histochemical and immunohistochemical techniques are crucial to the accurate diagnosis. This review details the histopathologic features of clear cell cutaneous proliferations, classifying them according their type of differentiation and paying special attention to the histopathologic differential diagnosis among them.

Clear Cell Differentiation in Eccrine Porocarcinoma as a High-Risk Feature: Epidemiologic and Pathologic Features of Eccrine Porocarcinoma in a Single-Center Case Series

ABSTRACT

Eccrine porocarcinoma (EPC) is a rare sweat gland malignancy. Recognition of histologic features is challenging, and specific pathologic features correlate with risk of poor outcome. This single-center retrospective review and case series of 58 EPC cases from 2000 to 2016 elucidates epidemiologic and pathologic characteristics of EPC. Pathology slides from 52 cases were analyzed by a dermatopathologist for standardized variable characteristics, including previously determined high-risk features (HRF) associated with poor prognosis. The incidence of EPC increased over the study period with 3 times more cases diagnosed in the last 4 years than in the first 4 years. Most cases were in the elderly males (mean age 75 years), and 50% were located in the head and neck region. Although 38% of tumors exhibited one histologic HRF, only 10% exhibited more than one. Of the HRF, a greater tumor depth was associated with both increased age (P = 0.04) and clear cell differentiation (P = 0.02). This study elucidates epidemiologic and pathologic features of EPC and highlights how age and clear cell differentiation can be associated with greater tumor depth, although further research is needed to determine whether clear cell differentiation is associated with poor clinical outcome.

NUT Is a Specific Immunohistochemical Marker for the Diagnosis of YAP1-NUTM1-rearranged Cutaneous Poroid Neoplasms

YAP1-NUTM1 fusion transcripts have been recently reported in poroma and porocarcinoma. NUTM1 translocation can be screened by nuclear protein in testis (NUT) immunohistochemistry in various malignancies, but its diagnostic performance has not been thoroughly validated on a large cohort of cutaneous epithelial neoplasms. We have evaluated NUT immunohistochemical expression in a large cohort encompassing 835 cases of various cutaneous epidermal or adnexal epithelial neoplasms. NUT expression was specific to eccrine poromas and porocarcinoma, with 32% of cases showing NUT expression. All other cutaneous tumors tested lacked NUT expression, including mimickers such as seborrheic keratosis, Bowen disease, basal cell carcinoma, squamous cell carcinoma, Merkel cell carcinoma, nodular hidradenoma, and all other adnexal tumors tested. Remarkably, NUT expression was more frequent in a distinct morphologic subgroup. Indeed, 93% of poroid hidradenoma (dermal/subcutaneous nodular poroma, 13/14) and 80% of poroid hidradenocarcinoma cases (malignant poroid hidradenoma, 4/5) showed NUT expression, in contrast to 17% and 11% of classic poroma (4/23) and porocarcinoma cases (4/35), respectively. RNA sequencing of 12 NUT-positive neoplasms further confirmed the presence of a YAP1-NUTM1 fusion transcript in all cases, and also an EMC7-NUTM1 gene fusion in a single case. In the setting of a cutaneous adnexal neoplasm, nuclear expression of NUT accurately and specifically diagnosed a specific subgroup of benign and malignant poroid tumors, all associated with a NUTM1 fusion, which frequently harbored a poroid hidradenoma morphology.

Eccrine Porocarcinoma: New Insights and a Systematic Review of the Literature

BACKGROUND

Eccrine porocarcinoma (EPC) is a rare cutaneous neoplasm with high potential for morbidity and mortality. Due to its rarity, there is a paucity of data profiling diagnosis, work-up, and management.

OBJECTIVE

To consolidate reported information on demographics, diagnostics, clinical behavior, treatment modalities, and patient outcomes in EPC to provide a reference tool to optimize diagnosis and management.

METHODS

A comprehensive PubMed search was performed from 1963 to November 2017 using PRISMA guidelines. This yielded 155 articles detailing 206 cases of porocarcinoma.

RESULTS

Eccrine porocarcinoma most often presents in elderly patients on the head and neck or lower limbs. Metastatic disease at presentation is not uncommon (22%). Primary tumor location is significantly correlated with presence of metastasis (p = .038). The most common treatment is excision followed by Mohs micrographic surgery (MMS), although the outcomes after MMS were superior to those after surgical excision.

CONCLUSION

This systematic review of individual patient data reveals that all patients should have a histological diagnosis with imaging considered for high-risk cases. Primary tumor location should also be considered in diagnostic and therapeutic decision-making. Although wide local excision (WLE) is currently the first-line treatment, MMS is becoming increasingly used, with evidence indicating improved outcomes as compared to those seen with WLE.

Clear cell proliferations of the skin

Clear cell proliferations of the skin consist of a diverse group of lesions characterized by the presence of cells with abundant clear cytoplasm. They may arise from primary, metastatic, or non-neoplastic origins, with their distinctive cytoplasmic clearing attributable to causes ranging from artifact to accumulation of materials such as glycogen, mucin, or lipids. Despite the heterogeneity of these lesions, their distinguishing characteristics may be subtle, especially at high power. As such, histologic diagnosis can be challenging, and proper consideration relies on an understanding of the scope of possible origins, etiologies, and key immunohistochemical staining patterns of the various entities. This review categorizes cutaneous clear cell neoplasms by histogenesis, and offers differential diagnostic strategies to aid in their clinicopathologic evaluation.

PHLDA1, a follicular stem cell marker, differentiates clear-cell/granular-cell trichoblastoma and clear-cell/granular cell basal cell carcinoma: a case-control study, with first description of granular-cell trichoblastoma

BACKGROUND

Granular-cell or clear-cell basal cell carcinomas (BCCs), and clear-cell trichoblastomas have rarely been reported in the literature. PHLDA1 is a follicular stem cell marker, the expression of which has been reported to differentiate trichoepithelioma from BCCs. We wondered whether (1) granular-cell trichoblastoma exists and (2) PHLDA1 expression can differentiate a clear- and/or granular-cell trichoblastoma and a BCC.

METHODS

In the records of 2 pathology departments, 12 clear- and/or granular-cell trichoblastomas and BCCs were found. Epidemiological, histopathological, and immunohistochemical data for PHLDA1, Ki67, and AE1-AE3; and cytokeratins 17, 19, 20, and 6hf were collected.

RESULTS

Trichoblastomas and clear- and/or granular-cell BCCs occurred in 7 patients (36-62 years; mean: 49) and in 5 patients (63-91 years; mean: 77), respectively. Three granular-cell trichoblastomas were identified. Both granular and clear-cell changes were present in 4 BCCs. The patterns of expression for AE1/AE3, CK17, CK19, CK6hf, and CK20 were not helpful in differentiating trichoblastoma from BCC. PHLDA1 expression was diffusely or partially present in all trichoblastomas (5/5) and absent in BCCs (0/4) (P = 0.008).

CONCLUSIONS

Granular- and/or clear-cell changes are rare findings in trichoblastoma and BCC. First, we show that granular-cell trichoblastomas do occur. Second, PHLDA1 expression is a useful addition in differentiating trichoblastoma and BCC.

A clinical study of dermatoses in diabetes to establish its markers

BACKGROUND

Cutaneous manifestations of diabetes mellitus generally appear subsequent to the development of the disease, but they may be the first presenting signs and in some cases they may precede the primary disease manifestation by many years.

AIMS

The aim of our study was to study the spectrum of dermatoses in diabetics, to know the frequency of dermatoses specific to diabetes mellitus (DM), and to establish the mucocutaneous markers of DM.

MATERIAL AND METHODS

The study was conducted at a diabetic clinic and our department between September 2008 and June 2010. Two hundred and twenty-four diabetic patients were included in the study group and those with gestational diabetes were excluded. Healthy age- and sex-matched individuals were taken as controls.

RESULTS

The male to female ratio was 1 : 1.21. Type 2 DM was seen in 89.7% and type 1 DM in 10.3% of the patients. Dermatoses were seen in 88.3% of the diabetics compared to 36% in non-diabetic controls (P<0.05). Cutaneous infections were the most common dermatoses followed by acanthosis nigricans and xerosis in diabetics. Type 2 DM was found to have an increased risk of complications than type 1 DM. Complications of diabetes were seen in 43.7% of the diabetic cases. Diabetic dermopathy, loss of hair over the legs, diabetic foot ulcer, and so on, were found to be the cutaneous markers of DM in our group of cases.

CONCLUSION

Dermatoses were more common in diabetics than non-diabetics. Cutaneous infections formed the largest group of dermatoses in DM.

The use of immunohistochemistry in the diagnosis of metastatic clear cell renal cell carcinoma: a review of PAX-8, PAX-2, hKIM-1, RCCma, and CD10

The diagnosis of metastatic clear cell renal cell carcinoma may be difficult in some cases, particularly in the small image-guided biopsies that are becoming more common. As targeted therapies for renal cell carcinoma are now standard treatment, the recognition and diagnosis of renal cell carcinoma has become even more critical. Many adjunctive immunohistochemical markers of renal epithelial lineage such as CD10 and RCCma have been proposed as aids in the diagnosis of metastatic renal cell carcinoma, but low specificities often limit their utility. More recently described markers (PAX-2, PAX-8, human kidney injury molecule-1, hepatocyte nuclear factor-1-β, and carbonic anhydrase-IX) offer the potential for greater sensitivity and specificity in this diagnostic setting; however, knowledge of their expected staining in other neoplasms and tissues is critical for appropriate use. In this review, we discuss the most widely used immunohistochemical markers of renal lineage with an emphasis on their sensitivity and specificity for metastatic clear cell renal cell carcinoma. Subsequently, we present a variety of organ-specific differential diagnostic scenarios in which metastatic clear cell renal cell carcinoma might be considered and we propose immunopanels for use in each situation.

Hypoxia-inducible factor 1-mediated regulation of PPP1R3C promotes glycogen accumulation in human MCF-7 cells under hypoxia

Hundreds of genes can be regulated by hypoxia-inducible factor 1 (HIF1) under hypoxia. Here we demonstrated a HIF1-mediated induction of protein phosphatase 1, regulatory subunit 3C gene (PPP1R3C) in human MCF7 cells under hypoxia. By mutation analysis we confirmed the presence of a functional hypoxia response element that is located 229bp upstream from the PPP1R3C gene. PPP1R3C induction correlates with a significant glycogen accumulation in MCF7 cells under hypoxia. Knockdown of either HIF1α or PPP1R3C attenuated hypoxia-induced glycogen accumulation significantly. Knockdown of HIF2α reduced hypoxia-induced glycogen accumulation slightly (but not significantly). Our results demonstrated that HIF1 promotes glycogen accumulation through regulating PPP1R3C expression under hypoxia, which revealed a novel metabolic adaptation of cells to hypoxia.

A case of clear cell eccrine porocarcinoma

Eccrine porocarcinoma (EP) is a rare malignant tumor arising from the intraepidermal eccrine duct. The tumor cells frequently contain glycogen, but prominent clear cell changes in EP are rarely reported. A 78-year-old woman presented with a slightly pruritic, erythematous, verrucous plaque on her left thigh. Histopathological examination revealed intraepidermal tumor cell nests composed of small basaloid cells and duct-like structures lined by periodic acid-Schiff (PAS)-positive cuticles. Besides the typical findings of EP, clear cell changes were predominantly observed in the tumor cell aggregations. Herein we report a case of the clear cell variant of EP rarely reported in previous literature.

[Eccrine porocarcinoma: report of four cases and literature review]

Eccrine porocarcinoma is an extremely rare skin tumor derived from the acrosyringium. Four cases of eccrine porocarcinoma are described, two males and two females, aged from 49 to 64 years. Tumors grew in an interval of one to 20 years. Lesions ranged from 1.2 x 2 cm to 4 x 5 cm and were on limbs or face. Two patients had basal cell carcinoma in a site different from the eccrine porocarcinoma. Two biopsies were described as eccrine poroma. Malignancy was observed in all cases after wide excision. Therefore, eccrine porocarcinoma should always be considered after a biopsy compatible with eccrine poroma.

Eccrine porocarcinoma of the auricle: a case report

Eccrine porocarcinoma (EP) is a rare skin malignant lesion representing 0.005-0.01% of all cutaneous tumors. It is a tumor that most commonly present in elderly people aged over 60 years. Approximately 250 cases of EP have been reported since this disease was first described in 1963. However, only three cases occurring specifically on the ear (including the current case) have been documented in the literature to date. Based on the rarity of EP of the ear, we present this 78-year-old man with EP on the right ear lobule, which was diagnosed accidentally during the management of other unrelated problems. The etiology, diagnosis, treatment and prognosis of this disease are discussed, with a brief review of the literature in this report.

Spiradenoma and spiradenocylindroma with an adenomatous or atypical adenomatous component: a clinicopathological study of 6 cases

We report 5 cases of spiradenoma and 1 case of spiradenocylindroma, which, in addition to areas of conventional growth, manifested an adenomatous component. This consisted of compactly situated, well-developed glands having small round lumens lined by inner pale to eosinophilic cells and surrounded by an outer well-formed peripheral layer of myoepithelial cells, which reacted with a variety of myoepithelial cell markers. In 1 case, apocrine secretion was evident in the glandular part of the lesion. In 4 of the 6 cases, the adenomatous component was a minor but significant portion of the tumors, but in 2 cases it was extensive, comprising approximately 20% of the tumor area. In 1 of these 2 cases, the luminal epithelium showed atypia including rare, atypical mitotic figures. In addition, there were foci of glands showing myoepithelial cell loss. As this alteration was limited and fairly well circumscribed within the tumor bulk, we regard it as an "atypical adenomatous component," but we cannot exclude the possibility that this may represent an incipient apocrine carcinoma, despite uneventful follow-up. Three cases also manifested clear cell areas. Immunohistochemical studies demonstrated that myoepithelial proliferation and overgrowth accounted for the clear cell change in some of the lesions.

Clear-cell porocarcinoma in situ: a cytologic variant of porocarcinoma in situ

Poromas are benign neoplasms composed of poroid and cuticular cells. Four histopathologic variants of poromas are accepted, according to the architectural features of the neoplasm: hidroacanthoma simplex or intraepidermal poroma; eccrine poroma, which is a poroma connected to the epidermis that extends to superficial dermis; dermal duct tumor, which develops when the neoplasm is composed of small, solid aggregations of poroid and cuticular cells confined to the dermis with little or no connection with the epidermis; and poroid hidradenoma, which is a solid-cystic, dermal poroma. The malignant counterpart of hidroacanthoma simplex is named malignant hidroacanthoma simplex or porocarcinoma in situ. This report describes an example of clear-cell malignant hidroacanthoma simplex, a cytologic variant of porocarcinoma in situ, which, to our knowledge, has not been previously reported. In contrast with other clear-cell neoplasms, a relation with diabetes mellitus could not be clearly established in this case.

Highly Aggressive Extraocular Sebaceous Carcinoma

Extraocular sebaceous carcinoma is an uncommon neoplasm usually localized on the head and neck. We report a case of sebaceous carcinoma of the axillary skin with a highly aggressive behavior. The patient was a 43-year-old black man who developed multiple cutaneous and lymph node metastases shortly after the excision of primary sebaceous carcinoma of the axillary skin. Many neoplastic aggregations were identified within the lumina of the dermal lymphatic vessels in the excised specimen of the primary neoplasm. Although extraocular sebaceous carcinoma has been traditionally considered a less aggressive neoplasm than its ocular counterpart, a review of the literature and this case demonstrate that extraocular sebaceous carcinoma may also lead to disseminated metastatic disease.

Eccrine porocarcinoma treated with Mohs micrographic surgery: A report of five cases

BACKGROUND

Eccrine porocarcinoma is a rare, locally aggressive, potentially fatal neoplasm. While wide local excision has traditionally been the treatment of choice, recurrences following excision are common.

OBJECTIVE

The purpose of this study was to review the traditional treatments of eccrine porocarcinoma as well as to introduce Mohs micrographic surgery as an alternative to wide local excision.

METHODS

We reviewed all cases of eccrine porocarcinoma seen at Emory University between 1985 and 1999. All cases were treated definitively with Mohs micrographic surgery. The clinical characteristics and outcome of each case are summarized.

RESULTS

Five patients with eccrine porocarcinoma were treated with Mohs micrographic surgery. There have been no recurrences to date, with an average follow-up of 2.1 years (ranging from 5 months to 4 years).

CONCLUSION

Follow-up of five patients supports the view that Mohs micrographic surgery may be an effective treatment for eccrine porocarcinoma.