Gauri Panse

Clinicopathological analysis of ATRX, DAXX and NOTCH Receptor Expression in Angiosarcomas

Multiple genetic alterations, including alternative lengthening of telomeres (ALT) and NOTCH mutations, have been described in angiosarcoma. Loss of α‐thalassaemia/mental retardation syndrome X‐linked (ATRX) and death domain‐associated protein 6 (DAXX) expression is frequently associated with the ALT phenotype. Additionally, inhibition of NOTCH signalling induces the development of malignant vascular tumours in mice, indicating a tumour suppressive role of the NOTCH pathway in the pathogenesis of angiosarcoma. The aim of this study was to evaluate the immunohistochemical expression of ATRX, DAXX and NOTCH receptors (NOTCH1 and NOTCH2) in a large cohort of angiosarcomas, and study their clinicopathological and prognostic significance.

Well-differentiated neuroendocrine tumors in skin: Terminology and diagnostic utility of cytokeratin 5/6 and p63: PANSE et al.

Well‐differentiated neuroendocrine tumors (WDNETs) in skin include metastases from visceral primary sites and very uncommonly, primary cutaneous carcinoid tumors. Cutaneous WDNET may present a diagnostic challenge and in particular can be mistaken for a benign skin adnexal tumor. In contrast to cutaneous adnexal tumors, metastatic adenocarcinomas to the skin are cytokeratin 5/6 (CK5/6) and p63 negative in the majority of cases. It is unclear if failure to stain with CK5/6 and p63 would be helpful in differentiating WDNETs from cutaneous adnexal neoplasms.

Index report of cutaneous angiosarcomas with strong positivity for tyrosinase mimicking melanoma with further evaluation of melanocytic markers in a large angiosarcoma series

Cutaneous angiosarcoma can be challenging to diagnose particularly when poorly vasoformative and studied on biopsies. We report a case of a cutaneous angiosarcoma with strong positivity for tyrosinase, the first to our knowledge, initially misdiagnosed as melanoma. We subsequently evaluated the reactivity of panmelanocytic cocktail (tyrosinase, HMB‐45 and Melan‐A), SOX10, tyrosinase and MITF in a large tissue microarray (TMA) of angiosarcoma. The TMA included 142 cases of angiosarcomas (29 cutaneous, 22 primary breast, 41 post‐radiation breast, 15 visceral, 26 deep soft tissue and bone, 5 chronic lymphedema‐associated and 4 angiosarcomas arising in other sarcomas). Immunohistochemical studies were performed with anti‐panmelanocytic cocktail, anti‐SOX10, anti‐MITF and anti‐tyrosinase antibodies. TMA staining results were scored on intensity and percentage of tumoral labeling. Aside from the index case, no cases (0 of 133) showed positivity for tyrosinase including 28 cutaneous angiosarcomas. One breast angiosarcoma (1 of 131) was positive for MITF. All cases were negative for SOX10 and panmelanocytic cocktail (0 of 132). Angiosarcomas can rarely be positive for tyrosinase and MITF. Pathologists should be cognizant of these rare exceptions to prevent confusion with melanoma. Additional immunohistochemical markers for vascular and melanocytic differentiation, thorough histological examination for vasoformative and in situ areas as well as clinical impression are helpful in these exceptionally problematic cases.

Basal cell carcinoma: CD56 and cytokeratin 5/6 staining patterns in the differential diagnosis with Merkel cell carcinoma

Basal cell carcinoma (BCC) can resemble Merkel cell carcinoma (MCC) on histopathological examination and while CK20 is a useful marker in this differential, it is occasionally negative in MCC. CD56, a sensitive marker of neuroendocrine differentiation, is sometimes used to identify MCC, but has been reportedly variably positive in BCC as well. In contrast, CK5/6 consistently labels BCC but is not expressed in neuroendocrine tumors.

The skin as a window to the blood: Cutaneous manifestations of myeloid malignancies

Cutaneous manifestations of myeloid malignancies are common and have a broad range of presentations. These skin findings are classified as specific, due to direct infiltration by malignant hematopoietic cells, or non-specific. Early recognition and diagnosis can have significant clinical implications, as skin manifestations may be the first indication of underlying hematologic malignancy, can reflect the immune status and stage of disease, and cutaneous reactions may occur from conventional and targeted agents used to treat myeloid disease. In addition, infections with cutaneous involvement are common in immunocompromised patients with myeloid disease. Given the varying presentations, dermatologic findings associated with myeloid malignancies can pose diagnostic challenges for hematologists and dermatologists. In this clinical review intended for the practicing hematologist/oncologist, we discuss the presentation, diagnosis, treatment, and prognostic value of the most common cutaneous manifestations associated with myeloid malignancies using illustrative macro- and microscopic figures and with a special emphasis on practical considerations.

Metastatic serous carcinoma presenting as inflammatory carcinoma over the breast-Report of two cases and literature review

Non‐mammary metastases involving breast are rare and most commonly involve the breast parenchyma. Infrequently, metastasis from an extramammary primary site presents as inflammatory carcinoma over the breast. Diagnosis of such lesions can be challenging, especially in patients with coexisting primary breast carcinoma. Few such cases have been described in literature; however, none of the previously reported cases had a prior history of primary breast carcinoma. We present 2 patients with history of breast carcinoma and serous carcinoma of ovarian/peritoneal origin that presented with inflammatory carcinoma over the breast. Biopsies from breast tissue showed atypical cells in the dermis forming cords and papillary structures. Histopathologic differential diagnosis included infiltrating ductal carcinoma of breast origin and metastatic serous carcinoma. Immunohistochemical studies showed that the tumor cells were positive for markers of ovarian origin such as PAX‐8 and CA‐125 and negative for breast markers such as GATA‐3, thus supporting the diagnosis. In summary, we describe the unusual presentation of metastatic serous carcinoma as inflammatory carcinoma over breast and discuss the diagnostic challenges in patients with coexisting primary breast and ovarian malignancies. We also review the morphologic features of tumors of breast and ovarian origin and the immunohistochemical stains to differentiate these 2 entities.

Maggot therapy for calciphylaxis wound debridement complicated by bleeding

STS: sodium thiosulfate INTRODUCTION Calciphylaxis is a rare disease with significant morbidity and mortality. Reported 1-year mortality is up to 80%, with sepsis as the leading cause of death. Althoughmost cases occur in end-stage renal disease patients on dialysis, nonuremic cases also occur. Maggot therapy for wound debridement in calciphylaxis has been reported, but the literature is limited.

Pityriasis rubra pilaris–like erythroderma in the setting of pembrolizumab therapy responsive to acitretin

Numerous cutaneous adverse effects have been associated with programmed death 1 (PD-1) inhibitors including maculopapular eruptions, pruritus, eczema, lichenoid reactions, leukoderma, psoriasis, sarcoidosis, immunobullous disorders, and Stevens-Johnson syndrome.1, 2 Here we report the first case, to our knowledge, of pityriasis rubra pilaris (PRP)-like erythroderma in the setting of anti–PD-1 therapy responsive to acitretin and topical steroids.

CD117 immunohistochemistry in sarcomatoid porocarcinoma

To the Editor, We read with interest the article by Goto et al regarding CD117 (KIT) as a useful marker to differentiate porocarcinoma from squamous cell carcinoma (SCC) with diffuse or focally positive expression in the former but uncommon in the latter. We noted that their series included 2 cases of sarcomatoid SCC (6.5% of 31 SCC cases), but no cases of porocarcinoma with sarcomatoid transformation (0/22). Sarcomatoid eccrine porocarcinoma is a rare tumor with very few cases

CD117 expression in adenosquamous carcinoma

To the Editor, We read with interest an excellent review of 30 cases reported as “squamoid eccrine ductal carcinoma,” which describes squamoid and eccrine differentiation in this potentially aggressive tumor characterized by the authors as being of adnexal/eccrine differentiation. We agree with the authors that the tumors they are describing may be indistinguishable from cutaneous adenosquamous carcinoma. While our intent is not to quibble over nomenclature, with recent articles describing the utility of CD117 in differentiating tumors with apocrine/eccrine differentiation from squamous cell carcinoma, we were curious as to whether our cases of adenosquamous carcinoma would stain with CD117. Goto and colleagues have shown CD117 to be positive in the majority of apocrine/eccrine tumors in their series; however, other authors have found it to be a less reliable marker of