Primary Cutaneous Rhabdoid Squamous Cell Carcinoma: A Case Report and Review of Molecular Features.

We present a rare case of rhabdoid squamous cell carcinoma (RSCC) on the scalp of a non-immunosuppressed male patient in his late 60s. This aggressive variant of squamous cell carcinoma (SCC) is characterized by tumor cells with eccentrically located nuclei and abundant eosinophilic cytoplasm, as observed on histopathological examination. While rhabdoid morphology has been reported in various anatomical sites, its occurrence in primary cutaneous tumors is exceptionally uncommon, with fewer than 10 cases documented to date.

Myxofibrosarcoma-Like Spindle Cell Squamous Cell Carcinoma of the Scalp: A Rare Mimic.

We report a challenging case of a man in his mid-70s diagnosed with a myxofibrosarcoma-like spindle cell squamous cell carcinoma (ML-SCC) on the scalp. This rare tumor shares cytologic features with spindle cell squamous cell carcinoma (SCC) with myxoid characteristics but also exhibits architectural elements typical of myxofibrosarcoma, making it nearly indistinguishable by routine light microscopic evaluation. Myxoid spindle cell carcinomas are exceptionally rare, and only one case of ML-SCC has been previously documented in the peer-reviewed medical literature.

A Unique Case of Cutaneous Schwannoma With Coexistent Masson's Hemangioma.

Schwannomas (SCHs) are benign neural tumors originating from Schwann cells of the peripheral nerve sheaths. These neoplasms typically exhibit hyalinized vessels with impaired vascular permeability; however, angioma-like features are rare. We report an intriguing case of a cutaneous SCH with unusual vascular changes in a 60-year-old female who presented with a tender nodular lesion on her lower back.

Melan-A-Positive Granular Cell Tumor With Extensive Intraneural and Perineural Spread: A Rare Case Report.

Cutaneous granular cell tumors (GCTs) are rare tumors that typically exhibit benign clinical behavior and are likely of Schwann cell origin. Some histologic and immunohistochemical variants of GCTs may present challenges due to infiltrative growth patterns, perineural invasion, and expression of Melan-A. In this case report, we present a 27-year-old male who had previously been diagnosed with a typical GCT on the back a few years ago.

Malignant peripheral nerve sheath tumor with glandular differentiation in a patient with neurofibromatosis type 1.

: The authors report an unusual case of malignant peripheral nerve sheath tumor with malignant differentiation arising as a subcutaneous nodule in the thigh of a 53-year-old woman with a history significant for neurofibromatosis type 1. Peripheral nerve sheath tumors containing a glandular component, commonly referred to as glandular peripheral nerve sheath tumors, are rare neoplasms found largely in patients with neurofibromatosis type 1. These tumors are frequently malignant; recognition of metastatic potential is made based on the atypical spindle-cell component.

Onycholemmal carcinoma: a morphologic comparison of 6 reported cases.

Background: We report 6 new cases of onycholemmal carcinoma, a rare, often misdiagnosed, subcategory of squamous cell carcinoma. All reported cases to date have been treated with amputation of the affected digit.

Objective: The purpose of this study was to present the clinical and pathological features of each new case and to discuss treatment options that spare digit functionality.

Chemoprevention of UV light-induced skin tumorigenesis by inhibition of the epidermal growth factor receptor.

The epidermal growth factor receptor (EGFR) is activated in skin cells following UV irradiation, the primary cause of nonmelanoma skin cancer. The EGFR inhibitor AG1478 prevented the UV-induced activation of EGFR and of downstream signaling pathways through c-Jun NH2-terminal kinases, extracellular signal-regulated kinases, p38 kinase, and phosphatidylinositol 3-kinase in the skin. The extent to which the UV-induced activation of EGFR influences skin tumorigenesis was determined in genetically initiated v-ras(Ha) transgenic Tg.

Immunohistochemistry and reverse transcriptase-polymerase chain reaction as methods for diagnostic determination of usher syndrome type IIa.

Objectives/hypothesis: Patients having null mutations in the USH2A gene do not produce usherin and therefore are not positive for immunohistochemical staining of the usherin protein. Thus, immunostaining for usherin can serve as a reliable diagnostic tool for Usher syndrome type IIa.

Study Design: Prospective.

Atypical lymphocytic lobular panniculitis.

Background: Although subcutaneous T-cell lymphoma (SCTCL) is considered an aggressive form of lymphoma, some patients manifest a long waxing and waning phase unaccompanied by constitutional symptoms.

Methods: Twelve patients were prospectively encountered, presenting with a lymphocytic panniculitis accompanied by lymphoid atypia, although not fulfilling criteria for SCTCL. Clinical, histologic, phenotypic, and genotypic analyses were conducted.

Leptomeningeal relapse of multiple myeloma following allogeneic stem cell transplantation.

Progressive multiple myeloma may manifest features of 'de-differentiation', including a plasmablastic appearance, failure to secrete paraprotein, extramedullary involvement, and resistance to treatment. A 44-year-old woman with kappa-light chain myeloma underwent allogeneic stem cell transplantation (SCT). Twenty months later she developed paraspinal plasmablastic myeloma in the absence of paraprotein in urine or myeloma in the marrow.