Pruritus as an early sign of abnormal scarring in the re-epithelialising phase of Toxic Epidermal Necrolysis.

We present a 28-year-old remote-living male who presented to our dermatology clinic with increasing pruritus over his torso and limbs in the context of a recent admission for Toxic Epidermal Necrolysis (TEN) secondary to paliperidone depot. Our case demonstrates that pruritus in the re-epithelialising phase of TEN may be a sign of abnormal scarring. Early assessment and measurement for compression garments is recommended.

Adult onset xanthogranuloma of the eyelid.

Purpose: To report a rare case of an eyelid lesion in an adult, with histological features of juvenile xanthogranuloma (JXG).

Observations: Juvenile xanthogranuloma primarily affects the skin of infants and young children. It infrequently can involve the structures of the eye and orbit and rarely occurs in individuals beyond the second decade of life.

Transient cryoglobulinaemic vasculitis following ChAdOx1 nCoV-19 vaccine.

Cryoglobulinaemic vasculitis is an immune-complex-mediated, systemic inflammatory syndrome usually involving small-to-medium vessels due to precipitation of cryoglobulins at <37°C. It can involve any organ but most commonly affects the skin. Associated conditions include infections (hepatitis C and HIV), haematological disorders (chronic lymphocytic lymphoma, monoclonal gammopathy of uncertain significance and multiple myeloma), autoimmune conditions (systemic lupus erythematosus and Sjogren syndrome) or as a complication following vaccination (influenza, pneumococcal and hepatitis B vaccines).

Intra- and intertumoral heterogeneity of liver metastases in a patient with uveal melanoma revealed by single-cell RNA sequencing.

Tumor heterogeneity is a major obstacle to the success of cancer treatment. An accurate understanding and recognition of tumor heterogeneity is critical in the clinical management of cancer patients. Here, we utilized single-cell RNA sequencing (scRNA-seq) to uncover the intra- and intertumoral heterogeneity of liver metastases from a patient with metastatic uveal melanoma.

S100/CD34-Positive Spindle Cell Mesenchymal Neoplasm Harboring KIAA1549-BRAF Fusion.

Mesenchymal neoplasms with oncogenic kinase activity due to genomic alterations in receptor tyrosine kinase genes are a morphologically heterogeneous group with a variable biologic potential. A subset of these neoplasms are characterized by immunophenotypic property of dual S100 protein/CD34 expression, histopathological resemblance to lipofibromatosis or peripheral nerve sheath tumors, and often alterations in neurotrophic tropomyosin-related kinase genes. In this article, we present a case of an S100 protein/CD34-positive spindle cell neoplasm harboring a rare BRAF gene rearrangement (KIAA1549-BRAF fusion) and discuss the clinical, histopathological, and molecular variations associated with such neoplasms.

Genome wide methylation profiling of selected matched soft tissue sarcomas identifies methylation changes in metastatic and recurrent disease.

In this study we used the Illumina Infinium Methylation array to investigate in a cohort of matched archival human tissue samples (n = 32) from 14 individuals with soft tissue sarcomas if genome-wide methylation changes occur during metastatic and recurrent (Met/Rec) disease. A range of sarcoma types were selected for this study: leiomyosarcoma (LMS), myxofibrosarcoma (MFS), rhabdomyosarcoma (RMS) and synovial sarcoma (SS). We identified differential methylation in all Met/Rec matched samples, demonstrating that epigenomic differences develop during the clonal evolution of sarcomas.

Chromosomal imbalances detected in NTRK-rearranged sarcomas by the use of comparative genomic hybridisation.

Aims: NTRK-rearranged sarcomas are emerging as a distinct class of sarcomas of particular importance in the era of targeted therapy. The aim of this study was to use array comparative genomic hybridisation (aCGH) to explore the cytogenetic profile of six adult soft tissue sarcomas harbouring NTRK gene fusions.

Methods And Results: aCGH was performed on six adult soft tissue sarcomas with proven NTRK rearrangements [NTRK1, n = 1 (TPM3-NTRK1); NTRK2, n = 1 (MTMR2-NTRK2); NTRK3, n = 4 (two ETV6-NTRK3; two with unknown partners).

Conjunctival Stromal Tumor: Report of 2 New Cases and Review of the Literature.

Conjunctival stromal tumor (COST) is an emerging entity with only a limited number of cases reported in the literature. In this report, we describe 2 additional cases, review the accumulative clinical and histopathological features and expand on the immunophenotypic property of this entity. COST appears to have a sporadic presentation, affecting both sexes and patients of variable ethnicity and age group and predominantly occurring on the bulbar conjunctiva as a slow-growing asymptomatic or slightly tender mass-like lesion.

Histiocytoid Melanoma.

While most melanomas display well-characterised and readily recognised architectural and cytomorphological features, unusual variants can create diagnostic difficulties. Variants which mimic benign or reactive processes are particularly problematic. We report 5 cases of melanoma characterised by a subtle microscopic appearance reminiscent of a benign dermal histiocytic infiltrate, which we refer to as "histiocytoid melanoma.

Renal Cell Carcinoma Antigen Expression in Primary Cutaneous Endocrine Mucinous Carcinomas: A Case Series of 14 Patients and Review of the Literature.

Endocrine mucin-producing sweat gland carcinoma (EMPSGC) and primary cutaneous mucinous carcinoma (PCMC) are both uncommon low-grade cutaneous adnexal tumors with predilection for the eyelids of elderly women. Their clinical appearance is nonspecific, typically presenting as a slowly growing poorly circumscribed papule, nodule, plaque, or swelling. Histological features of EMPSGC include a lobulated dermal neoplasm with bland cytology and an invasive mucinous component in up to half of the cases.

Droplet Digital PCR for Mutation Detection in Formalin-Fixed, Paraffin-Embedded Melanoma Tissues: A Comparison with Sanger Sequencing and Pyrosequencing.

The identification of somatic mutations is crucial for guiding therapeutic decisions about personalized melanoma treatment. However, genetic analysis of tumors is usually performed on limited and often low-quality DNA from tumors with low tumor cellularity and high tumor heterogeneity. Different mutation-detection platforms exist, with varying analytical sensitivities.

Pseudomelanomas Following Stevens-Johnson Syndrome.

In this report, we present a novel case of pseudomelanoma, similar to that seen in a recurrent/traumatized nevus, in pre-existing nevi in a 36-year-old man a few months after recovering from an episode of severe Stevens-Johnson syndrome. The mechanism responsible for the atypical transformation of these nevi is likely the release of cytokines and growth factors in the microenvironment during the repair/regeneration process. It is important to be aware of this phenomenon, and specific inquiry about potential recent blistering skin disorder in addition to the other causes of trauma should be made when dealing with cases of pseudomelanoma to avoid misdiagnosis.

Metastatic Cellular Blue Nevus: A Rare Case With Metastasis Beyond Regional Nodes.

In this study, we present a rare case of a 35-year-old man with a long-standing blue-black lesion on his left hand with subsequent infraclavicular and axillary lymph node tumor deposits. The hand lesion and lymph nodes were excised revealing histological, immunohistochemical, and molecular findings consistent with cellular blue nevus. Despite nonregional lymph node involvement, there has been no progression at 12-months follow-up.

Detection of Epidermal Growth Factor Receptor Mutations in Lung Adenocarcinoma: Comparing Cobas 4800 EGFR Assay With Sanger Bidirectional Sequencing.

Introduction: Accurate detection of epidermal growth factor receptor (EGFR) mutations has a crucial role in the current treatment of patients with lung adenocarcinoma, and identification of clinically relevant mutations would qualify patients for treatment with tyrosine kinase inhibitors. Historically, Sanger sequencing has been used as the reference standard assay for EGFR mutational analysis; however, Cobas 4800 is a relatively new method. In the present study, we compared the performance of the Cobas assay against that of Sanger sequencing.

Malignant Melanocytic Matricoma: A Report of 2 Cases and Review of the Literature.

Background: To describe 2 cases of melanocytic matricoma with malignant histological features and systematically review previously reported cases of malignant melanocytic matricoma.

Methods: Two cases of malignant melanocytic matricoma were identified from the practice of the authors. Additional 3 cases were identified in the literature.

Extramedullary hematopoiesis associated with organizing peritoneal hemorrhage: a report of 5 cases in patients presenting with primary gynecologic disorders.

Extramedullary hematopoiesis (EMH) usually occurs in patients with severe anemia or myelofibrosis, and involvement of the serous cavities is uncommon. A total of 5 cases of peritoneal EMH are presented in patients presenting with primary gynecologic pathology including endometrial adenosarcoma (n=2), ovarian leiomyosarcoma, and ovarian endometrioid adenocarcinoma (each n=1), all of which were associated with peritoneal metastases; the remaining patient had a hemorrhagic benign ovarian cyst. All cases were associated with organizing peritoneal hemorrhage, and EMH was localized to the reactive granulation tissue.

An evaluation of the morphologic features of low-grade mucinous neoplasms of the appendix metastatic in the ovary, and comparison with primary ovarian mucinous tumors.

It may be difficult to distinguish ovarian involvement by a low-grade appendiceal mucinous neoplasm (LAMN) from a primary gastrointestinal-type primary borderline (proliferative) ovarian tumor (IBMT) or an ovarian mucinous tumor arising within a teratoma, particularly when the latter is associated with mucinous ascites/pseudomyxoma peritonei. We noted that LAMNs involving the ovaries show 2 distinctive histologic features, "scalloped" glands and subepthelial stromal clefts, whereas IBMTs more often are associated with reactive cellular stroma and histiocyte aggregates (mucin granulomas). The frequency of these features was investigated in 18 LAMNs (16 with pseudomyxoma peritonei), 18 primary IBMTs, and 6 teratoma-associated mucinous tumors (selected on the basis of associated pseudomyxoma peritonei).