Granulomatous dermatitis secondary to vemurafenib in a child with Langerhans cell histiocytosis.

We present a 3-year-old boy with Langerhans cell histiocytosis who developed granulomatous dermatitis while taking vemurafenib. Vemurafenib currently has Food and Drug Administration approval for the treatment of BRAF V600E+ metastatic melanoma in adults, but recent discoveries of BRAF V600E in more than half of tested Langerhans cell histiocytosis lesions have prompted clinical trials of vemurafenib therapy for children with refractory, multisystem Langerhans cell histiocytosis. This report contributes to the knowledge of its potential side effects when used in children.

Histopathology of Cutaneous Inflammatory Disorders in Children.

Inflammatory dermatoses encompass a variety of histologic patterns that affect different portions of the skin. In spongiotic, psoriasiform, lichenoid, pityriasiform, and blistering disorders, there are predominately epidermal and junctional activities with variable superficial dermal inflammation. Hypersensitivity reactions can show either epidermal or mostly dermal changes depending on whether the exposure of the exogenous allergen occurs through an external or internal route, respectively.

Diagnostic utility of SOX11 immunohistochemistry in differentiating cutaneous spread of mantle cell lymphoma from primary cutaneous B-cell lymphomas.

Background: Mantle cell lymphoma (MCL) is associated with the worst prognosis among low-grade B-cell lymphomas. While cutaneous involvement by nodal or systemic MCL is uncommon, its differentiation from primary cutaneous B-cell lymphoma (CBCL) or cutaneous involvement by other extra-cutaneous BCL is challenging as neither histomorphology nor immunophenotype can be absolutely specific. We analyzed the diagnostic utility of SOX11 immunohistochemistry in differentiating secondary cutaneous MCL from other low-grade CBCL.

Cutaneous squamous cell carcinoma progression is associated with decreased GATA-3 immunohistochemical staining.

Background: The GATA family of transcription factors is an essential regulator of cellular proliferation and differentiation. In the skin, GATA-3 is critical for epidermal stratification and maintenance of barrier function. A role for GATA-3 in the development of human cutaneous squamous cell carcinoma (SCC) is not known.

Fluoroscopy-Guided Percutaneous Vertebral Body Biopsy Using a Novel Drill-Powered Device: Technical Case Series.

Background: A novel coaxial biopsy system powered by a handheld drill has recently been introduced for percutaneous bone biopsy. This technical note describes our initial experience performing fluoroscopy-guided vertebral body biopsies with this system, compares the yield of drill-assisted biopsy specimens with those obtained using a manual technique, and assesses the histologic adequacy of specimens obtained with drill assistance.

Methods: Medical records of all single-level, fluoroscopy-guided vertebral body biopsies were reviewed.

CT-guided percutaneous skull biopsy using a drill-assisted system: Technical report of two cases.

The OnControl coaxial biopsy system (Vidacare Corporation, Shavano Park, TX) includes an inner diamond-tipped access needle and hollow biopsy needle that engage with a battery-powered hand drill. Herein, we report the use of this novel device to perform two CT-guided percutaneous skull biopsies. Both procedures were performed without complication and facilitated a pathologic diagnosis.

Delayed vertebral body collapse after stereotactic radiosurgery and radiofrequency ablation: Case report with histopathologic-MRI correlation.

Stereotactic radiosurgery and percutaneous radiofrequency ablation are emerging therapies for pain palliation and local control of spinal metastases. However, the post-treatment imaging findings are not well characterized and the risk of long-term complications is unknown. We present the case of a 46-year-old woman with delayed vertebral body collapse after stereotactic radiosurgery and radiofrequency ablation of a painful lumbar metastasis.

Expression of helper T cell master regulators in inflammatory dermatoses and primary cutaneous T-cell lymphomas: diagnostic implications.

Background: Mycosis fungoides (MF) is a neoplasm of skin-homing CD4(+) helper T (TH) lymphocytes with dysregulation of TH1 and TH2 immunity. Diagnosis of MF is challenging, as there is significant morphologic overlap with other dermatologic entities.

Objective: We investigated diagnostic utility of TH1- and TH2-specific markers, T-bet, and GATA-3, respectively, in MF and its reactive and neoplastic mimics.

T-cell prolymphocytic leukemia frequently shows cutaneous involvement and is associated with gains of MYC, loss of ATM, and TCL1A rearrangement.

T-cell prolymphocytic leukemia (T-PLL) is a rare aggressive mature T-cell leukemia with frequent cutaneous presentation, which has not been well characterized. Among the 25 T-PLLs diagnosed between 1990 and 2013 at our institution, 32% (8/25) showed cutaneous manifestations, presenting as rash, purpura, papules, and ulcers. The skin biopsies showed leukemia cutis with perivascular and periadnexal irregular, small to medium-sized lymphoid infiltrates without epidermotropism.

Clinicopathologic features of adult T-cell leukemias/lymphomas at a North American tertiary care medical center: infrequent involvement of the central nervous system.

Human T-cell lymphotropic virus type 1 is associated with adult T-cell leukemia/lymphoma (ATLL). Published series of ATLLs seen at a United States medical institution are rare. We present the features of 4 ATLLs diagnosed at our North American tertiary care medical center from 1990 to 2012.