Pediatric cutaneous T-cell post-transplant lymphoproliferative disorder: Case report and review of the literature.

Post-transplant lymphoproliferative disease (PTLD) is a rare lymphoid and/or plasmacytic proliferation that occurs in the context of immunosuppression because of solid organ transplantation (SOT) and allogeneic hematopoietic stem cell transplantation (HSCT). PTLD is the most common cancer in children who receive a SOT or HSCT, occurring in up to 13% of these patients. The majority of PTLDs are extracutaneous B-cell lymphomas, with only 12% to 14%, representing the T-cell phenotype. PTLDs can involve the skin and behave like an aggressive lymphoma, and are among the most serious and potentially fatal complications of transplantation. Here we present a case report and review of the literature of pediatric cutaneous PTLD.

Atypical pilar leiomyomatosis: an unusual presentation of multiple atypical cutaneous leiomyomas.

Cutaneous leiomyomas are relatively common benign smooth muscle tumors that may arise as solitary or multiple lesions. Rare forms with cytologic atypia, and features similar to symplastic leiomyomas of the uterus, have been described. We report a case of multiple cutaneous atypical leiomyomas occurring in a 43-year-old man with long history of lesions of the right lower leg and a family history of leiomyomatosis. Twenty of the lesions were excised due to pain and were examined histopathologically. All the lesions exhibited features described in atypical leiomyomas of the skin including increased cellularity, nuclear atypia and pleomorphism, and low mitotic activity. The biologic potential of cutaneous atypical leiomyomas is uncertain. Only a few case reports exist in the literature with the majority occurring as solitary lesions. Most of the reported atypical leiomyomas have behaved in a benign fashion. However, a rare account of transformation to leiomyosarcoma emphasizes the need for long-term follow up of these patients. Herein, we describe a case of multiple atypical cutaneous leiomyomas arising in the setting of familial leiomyomatosis.

Mantle Cell Lymphoma Presenting with Cutaneous Lesions: A Rare Manifestation of a Systemic Disease.

OBJECTIVES: Cutaneous lymphoma is a broad term used to describe any type of lymphoma involving the skin. They may be primary, arising in the skin, or secondary, resulting from spread of a systemic lymphoma. Cutaneous involvement of mantle cell lymphoma (MCL) is extremely rare and most often occurs secondarily. To date, less than 100 cases of MCL involving the skin have been described in the English literature. We describe a case of MCL involving the skin as the clinical presentation of disease in a 74-year-old man and highlight the radiographic and pathologic findings, treatment course, and prognosis.

Targeting mitochondrial oxidative stress with MitoQ reduces NET formation and kidney disease in lupus-prone MRL-lpr mice.

OBJECTIVES: Recent investigations in humans and mouse models with lupus have revealed evidence of mitochondrial dysfunction and production of mitochondrial reactive oxygen species (mROS) in T cells and neutrophils. This can provoke numerous cellular changes including oxidation of nucleic acids, proteins, lipids and even induction of cell death. We have previously observed that in T cells from patients with lupus, the increased mROS is capable of provoking oligomerisation of mitochondrial antiviral stimulator (MAVS) and production of type I interferon (IFN-I). mROS in SLE neutrophils also promotes the formation of neutrophil extracellular traps (NETs), which are increased in lupus and implicated in renal damage. As a result, in addition to traditional immunosuppression, more comprehensive treatments for lupus may also include non-immune therapy, such as antioxidants. METHODS: Lupus-prone MRL-lpr mice were treated from weaning for 11 weeks with the mitochondria-targeted antioxidant, MitoQ (200 µM) in drinking water. Mice were then assessed for ROS production in neutrophils, NET formation, MAVS oligomerisation, serum IFN-I, autoantibody production and renal function. RESULTS: MitoQ-treated mice manifested reduced neutrophil ROS and NET formation, decreased MAVS oligomerisation and serum IFN-I, and reduced immune complex formation in kidneys, despite no change in serum autoantibody . CONCLUSIONS: These findings reveal the potential utility of targeting mROS in addition to traditional immunosuppressive therapy for lupus.

Melanotic schwannoma arising in association with nevus of Ota: 2 cases suggesting a shared mechanism.

Melanotic schwannoma is a rare markedly pigmented peripheral nerve sheath tumor comprising cells with prominent melanization and schwannian features. The psammomatous variety is associated with Carney complex, a multiple neoplasia syndrome with spotty skin pigmentation. We present the first 2 reported cases of melanotic schwannoma arising in patients with a history of nevus of Ota, a rare dermal melanosis believed to represent a failure of melanocyte migration to the epidermis during embryogenesis. Case 1 involves a 40-year-old woman with a 1.8-cm, deeply pigmented, trigeminal nerve mass and pigmentation of the maxillary sinus mucosa and bone. Case 2 involves a 53-year-old woman with a 1.5-cm mass adjacent to the clavicle. Microscopically, both masses consist of partially encapsulated epithelioid and spindle cells with abundant melanin pigment, arising in association with peripheral nerves. Morphological, immunohistochemical, and ultrastructural features support a diagnosis of melanotic schwannoma. No psammoma bodies are noted, and neither patient exhibits any additional features of Carney complex. Melanotic schwannoma is most often benign but has been associated with malignant behavior in some cases. Distinguishing this nerve sheath tumor from malignant melanoma can be difficult but is of great clinical importance due to differences in prognosis and treatment.

Giant cell reparative granuloma of the middle phalanx of the foot: a review and case report.

Giant cell reparative granuloma is a benign, rare non-neoplastic intraosseous lesion. It is found in various sites throughout the body, including the foot. This uncommon lesion has histological and radiographic features that are similar to other giant cell lytic lesions. Therefore, it is essential to be aware of this lesion to avoid confusion with more aggressive tumors. The purpose of this case report is to present the histological and radiographic findings of a 26-year-old female who had successful surgical excision and resolution of a giant cell reparative granuloma in the middle phalanx third digit left foot.

Colonic ganglioneuromatous polyposis and metastatic adenocarcinoma in the setting of Cowden syndrome: a case report and literature review.

Cowden syndrome is a rare, autosomal-dominant, multisystem disorder characterized by hamartomatous tissue overgrowth and an increased risk of breast, thyroid, and endometrial cancers. Most of the cases arise from germline mutations of the phosphatase and tensin homologue tumor suppressor gene. An association with colon cancer remains unproven but has been suggested in previous reports. We present the case of a 42-year-old man with colonic ganglioneuromatous polyps and an adjacent colonic adenoma giving rise to a signet-ring adenocarcinoma with lymph node metastases in the setting of Cowden syndrome. Although gastrointestinal polyps are a common feature of Cowden syndrome, reports of ganglioneuromatous polyps and malignant degeneration are rare. Cutaneous features of Cowden syndrome in our patient include "cobblestone" lesions of the tongue and oral mucosa, facial trichilemmomas, multiple acral keratoses, and a storiform collagenoma.