NUT Expression Is of Diagnostic Utility in the Distinction of Digital Papillary Carcinoma From Poroid Hidradenoma.

ABSTRACT: The distinction between digital papillary adenocarcinoma (DPAC) and benign cutaneous adnexal tumors is clinically important and can be challenging. Poroid hidradenoma frequently occurs at acral sites and can show a number of histological features, which overlap with digital papillary adenocarcinoma. Recent work has shown that YAP1-NUTM1 fusions are frequent in poroid hidradenoma and are associated with nuclear protein in testis (NUT) expression by immunohistochemistry. We evaluated the expression of NUT-1 by immunohistochemistry in 4 cases of DPAC and 4 cases of poroid hidradenoma. Three of 4 cases of poroid hidradenoma showed strong NUT-1 expression, with no staining in any of the cases of DPAC. These results suggest that NUT-1 immunohistochemistry may be a useful additional tool in evaluating this differential diagnosis.

Correlation of FISH and PRAME Immunohistochemistry in Ambiguous Superficial Cutaneous Melanocytic Proliferations.

ABSTRACT: Preferentially expressed antigen in melanoma (PRAME) is a tumor-associated repressor of retinoic acid signaling which is expressed in melanoma and has emerged as a potential biomarker for malignant behavior in melanocytic neoplasms. Although ancillary molecular techniques such as fluorescence in situ hybridization (FISH) are established techniques in the diagnosis of problematic cutaneous melanocytic proliferations, they are expensive, time-consuming, and require appropriate infrastructure, which places them out of reach of some laboratories. The advent of readily available commercial antibodies to PRAME has the potential to provide a more accessible alternative. The aim of this study was to determine whether immunohistochemistry for PRAME could serve as a surrogate for FISH analysis in a subgroup of challenging superficial melanocytic proliferations. Cases which had previously been submitted for FISH analysis were stained for PRAME and interpreted by a panel of at least 3 dermatopathologists is a blinded fashion. Of a study set of 55 cases, 42 (76%) showed a pattern of PRAME immunostaining which was concordant with the cytogenetic interpretation, with an unweighted kappa of 0.42 (representing mild-to-moderate agreement). Thus, although there was a correlation between positive immunohistochemistry for PRAME and abnormal findings on FISH analysis, in our view, the concordance was not sufficient to enable PRAME immunohistochemistry to act as a surrogate for FISH testing. Our findings reiterate the principle that interpretation of problematic superficial melanocytic proliferations requires a synthesis of all the available data, including clinical scenario, morphological features, immunohistochemistry, and ancillary molecular investigations.

Recurrent Necrotizing Fasciitis: A Case Report of Fulminant and Sub-Acute Necrotizing Fasciitis in a Diabetic Patient.

Necrotizing fasciitis is an uncommon and deadly disease entity characterized by rapidly progressing skin and soft tissue destruction. It presents on a spectrum from an initially indolent appearing sub-acute form to a hyperacute fulminant course. It may often be misdiagnosed due to the paucity of signs early in the disease course and as it can initially mimic other less serious soft tissue infections. Necrotizing soft tissue infections have both high morbidity and mortality. We present a case of a 72-year-old male patient with two anatomically and temporally separate necrotizing infections. The first necrotizing infection was diagnosed after an extended time, due to the subacute disease course in the setting of an abdominal wall infection. The second presentation was a hyperacute fulminant course in the setting of a necrotizing infection of the scrotum. In both instances, once identified, appropriate management was followed: resuscitation, broad-spectrum antibiotics, and most importantly radical surgical debridement. Extensive multidisciplinary inpatient and outpatient input was required to aid the patient's recovery. The presented case demonstrates the necrotizing soft tissue infection's spectrum of disease and the diagnostic dilemma it presents to family physicians and emergency departments alike. The only definitive management step is immediate and radical resection of the affected tissue. Extensive debridement and the resultant tissue defect require comprehensive multidisciplinary care during the extended rehabilitation and wound care treatment plan. Rapid recognition, urgent surgical debridement, and specialist care are required to reduce the mortality and morbidity associated with necrotizing soft tissue infections.

Sebaceous lesions of the skin.

Sebaceous differentiation is commonly seen in cutaneous neoplasms, both in the context of lesions showing predominantly sebaceous differentiation (e.g., sebaceous adenoma, sebaceoma and sebaceous carcinoma), or as more focal sebaceous components in neoplasms with other primary lines of differentiation. Sebaceous changes can also be a component of benign cystic lesions or epidermal tumours, and sebaceous hyperplasia is commonly encountered. This review is intended to provide an overview of the cutaneous lesions with sebaceous differentiation, with a particular emphasis on facilitating histological diagnosis of neoplasms. In addition, the role of immunohistochemical studies is outlined, as well as the evaluation of potential cases of Muir-Torre syndrome.

Microscopic extraovarian sex cord proliferations: an undescribed phenomenon.

AIMS: To report a previously undescribed phenomenon of incidentally detected microscopic proliferations of sex cord cells, often mimicking adult granulosa cell tumour or sex cord tumour with annular tubules, in extraovarian locations. METHODS AND RESULTS: The six cases were in patients aged 23-58 years. The proliferations were located in the fallopian tube in three cases, and in paraovarian connective tissues, the pelvic side wall, and appendiceal serosa (one case each). Microscopically, they were typically composed of well-demarcated nests of regular cells with round/ovoid vesicular nuclei, some containing grooves. Microfollicular and/or cribriform arrangements were present in three cases. In five cases, the sex cord lineage was confirmed by positive staining with inhibin and/or calretinin and other sex cord markers. FOXL2 mutation analysis was performed in one case, but was inconclusive. Bilateral oophorectomies and bilateral cystectomies were performed in three cases and one case respectively; there was no sex cord-stromal neoplasm in the removed ovaries. In the two cases in which the ovaries were not removed, imaging showed no suspicious features. Follow-up in four cases (11 months-6 years) has been uneventful. CONCLUSIONS: The pathogenesis of these microscopic extraovarian sex cord proliferations is unknown, but they may represent non-neoplastic proliferations of embryonic remnants.

Cutaneous intravascular anaplastic large T-cell lymphoma: a case report and review of the literature.

Intravascular lymphoma (IVL) is a rare subtype of extranodal lymphoma. In the 2008 WHO classification of tumors of the hematopoietic and lymphoid tissues intravascular large B-cell lymphoma is included as a distinct entity. IVL of T-cell type is not included as a diagnostic category and is only mentioned in passing by Nakamura et al. as "a different entity" in their discussion of intravascular large B-cell lymphoma. T-cell IVL is rare, the majority of cases being of natural killer/T-cell phenotype. Exceptionally rare is primary cutaneous intravascular anaplastic large T-cell lymphoma. We present such a case in an otherwise well 39-year-old female having disease limited to the skin established after detailed staging investigations. This is only the third such case described in the literature. We report the clinicopathological features of this case and also review previously documented cases of cutaneous intravascular anaplastic large cell lymphoma.

Gastric intraepithelial neoplasia in a Western population.

BACKGROUND AND STUDY AIMS: Descriptions of the natural history and endoscopic appearances of gastric dysplasia/intraepithelial neoplasia (IEN) that originate mainly from Europe. Currently, there are no Australian data available. We aimed to document endoscopic appearances and progression rates of gastric IEN and to determine the significance of indefinite for IEN. PATIENTS AND METHODS: This is a retrospective study, in which cases diagnosed with gastric IEN were identified between 2000 and 2009. Endoscopic appearances, progression rates to more advanced IEN or cancer, and long-term outcomes were recorded. RESULTS: A total of 160 cases with IEN (26.9% high grade, 57.5% low grade, 15.6% indefinite) were identified. The mean age was 67.8 years and 53.8% were men. Endoscopic lesions were polypoid in 29.4% and nonpolypoid in 70.6%. The most common location was the antrum (58.7%). Forty patients had an intervention and 76 underwent endoscopic follow-up only. Twenty-two cancers were diagnosed; three who had an intervention were diagnosed within 12 months, one with low-grade intraepithelial neoplasia developing a cancer after 9.9 years, and 13 undergoing surveillance only, were diagnosed with cancer within 12 months of index endoscopy. Five cases had cancer after a mean of 2.6 years. Forty-seven cases initially labelled as indefinite; following rereview 25 remained unchanged, 11 reclassified as negative for IEN, 10 as low grade, and one as high grade. Three of these cases developed cancer over the study period. CONCLUSION: We concluded that (a) majority of gastric IEN are associated with endoscopic lesions, (b) high rate of early cancer diagnosis was observed (c) rates of progression to cancer were lower than reported rates, and (d) indefinite for IEN is not innocuous requiring an expert pathologist's review.