Yetish Sing

Cryptococcal inflammatory pseudotumors.

“Inflammatory pseudotumors” (IPTs) embrace a heterogeneous spectrum of reactive, infective, and neoplastic entities, that are characterized by a clinical mass composed of a histologic proliferation of spindle cells in a background of inflammatory cells and collagen fibers. Although a spectrum of microorganisms have been identified in infective IPTs, mycobacterial infective IPTs are reported most commonly. We document 5 solitary cryptococcal IPTs, in 2 males and 3 females, aged 19 to 43 years, in the soft tissues of the anterior chest wall, thigh, and arm. All were HIV-positive and had been treated for disseminated cutaneous and/or meningeal cryptococcosis with antifungal therapy, 6 to 12 months earlier. The specimens demonstrated a storiform arrangement of plump spindle cells, in addition to spindle and polygonal cells that were arranged in a haphazard manner. Background lymphocytes, plasma cells, and fibrosis were noted, in addition to scattered giant cells and focal necrosis. On high-power examination, Cryptococcus neoformans yeasts were identified within and between vacuolated spindle and polygonal cells on routine and special stains, confirming cryptococcal IPTs. Immunophenotyping of the spindle cells confirmed a mixed histiocytic and myofibroblastic lineage, with a predominance of the former. In documenting 5, hitherto unreported, pseudotumoral spindle cell reactions to C. neoformans, we not only highlight the need for intense appraisal of all IPTs for infective agents on routine and special stains and investigations, but also postulate that a complex host-fungus interaction, coupled with an exuberant, myofibroblastic response to incomplete therapy, are the pathogenetic drive for the pseudotumoral presentation.

Gastric plexiform angiomyxoid myofibroblastic tumor

Plexiform angiomyxoid myofibroblastic tumor (PAMT) is a relatively recently described gastric tumor with a peculiar plexiform growth pattern. PAMT is typified by a myofibroblastic immunophenotype that distinguishes it from the more common gastrointestinal stromal tumors and the rarely documented fibromyxomas. We report an additional PAMT, the seventh tumor with this label, which was an incidental finding on abdominal computed tomography scan of a 35‐year‐old Indian female. The tumor measured 4 × 3 × 2 cm and demonstrated plexiform architecture, myxoid stroma, prominent vasculature and spindled cells with myofibroblastic differentiation. The clinicopathological features, progesterone immunopositivity, hitherto undocumented, and mimicry of other primary and secondary gastric mesenchymal tumors, including endometrial stromal sarcoma, are discussed.

Dermal Epstein Barr virus--associated leiomyosarcoma: tocsin of acquired immunodeficiency syndrome in two children.

Although rare in childhood, a relatively high incidence of smooth muscle tumors are recognized in patients with AIDS, mainly in association with Epstein Barr virus (EBV) infection. Although EBV-associated smooth muscle tumors have been documented rarely in the subcutis of AIDS patients, dermal involvement has not been described to date. This report describes dermal EBV-associated leiomyosarcomas (EBV-LMS) with a nodular but superficial plaque-like appearance on the lower limbs of 2 males, 9 and 12 years old. Histopathological assessment of the excised lesions demonstrated hypercellular mitotically active dermal tumors with hyperchromatic spindle and round cells, arranged in short fascicles and sheets, with microfoci of necrosis. A smooth muscle immunophenotype, including prominent desmin immunopositivity, and positive EBV-encoded RNA in situ hybridization investigation confirmed a diagnosis of EBV-LMS. Subsequent HIV seropositivity and AIDS were confirmed in both patients. Both patients also had pulmonary tuberculosis and received antituberculous therapy. Patient 1 had a 3 cm re-excision of the prior tumor site. He received highly active antiretroviral therapy, completed 6 months of antituberculous therapy, achieved immune reconstitution and viral suppression and is tumor-free 2 years after tumor excision. Patient 2 died before further therapy. The immune status, presence, and appropriate therapy of co-existent systemic infection and highly active antiretroviral therapy in AIDS patients with EBV-LMS are crucial to a favorable outcome.

Molluscum‐like cutaneous cryptococcosis: a histopathological and pathogenetic appraisal

Background:  Molluscum‐like cutaneous cryptococcosis (MLCC) is characterized by hypopigmented or skin‐colored papules with central umbilication. The histomorphological nuances of Cryptococcus neoformans infection that effect mimicry of molluscum contagiosum are undocumented. This histopathological study was undertaken to assess the histopathological characteristics of MLCC and to determine potential evolutionary pathogenetic mechanisms and significance.

Periampullary Epstein-Barr virus–associated myopericytoma

Although myopericytoma occurs predominantly in the extremities, a wider anatomical distribution, malignant variant, and association with Epstein-Barr virus have been recognized recently. However, benign, malignant, or Epstein-Barr virus-myopericytoma has not been documented in the gastrointestinal tract to date. We report a periampullary Epstein-Barr virus-myopericytoma in a patient with AIDS who presented with obstructive jaundice. The tumor contained round, oval, and plump spindle cells arranged around and between slit-like, dilated, and staghorn vessels. A malignant variant was favored based on the presence of cellular pleomorphism, 23 mitoses per 10 high-power fields, necrosis, and lymphovascular involvement. Immunohistochemistry confirmed a myoid immunophenotype with h-Caldesmon positivity and desmin negativity. Epstein-Barr virus-encoded RNA was demonstrated by in situ hybridization. Heightened awareness of Epstein-Barr virus-myopericytoma and occurrence in the periampullary location are critical to diagnostic workup and differentiation of myopericytoma from other mesenchymal tumors and pseudotumors especially in small biopsies and in patients with AIDS.

Extra-anogenital bilharziasis cutanea tarda revisited.

Background:  Even in schistosomiasis‐endemic areas, extra‐anogenital bilharziasis cutanea tarda (E‐BCT) is rare. To date, the occurrence of E‐BCT in pre‐existing cutaneous pathology is undocumented. The study was undertaken to document the expanded clinicopathological spectrum and to comment on the putative pathogenetic mechanisms of a Schistosoma hematobium‐associated E‐BCT.

Extra‐uterine myoid tumours in patients with acquired immunodeficiency syndrome: a clinicopathological reappraisal

Ramdial P K, Sing Y, Deonarain J, Vaubell J I, Naicker S, Sydney C, Hadley L G P, Singh B, Kiratu E, Gundry B & Sewram V 
(2011) Histopathology 59, 1122–1134 
Extra‐uterine myoid tumours in patients with acquired immunodeficiency syndrome: a clinicopathological reappraisal

Pediatric Plasmablastic Lymphoma A Clinicopathologic Study

Plasmablastic lymphoma (PBL) is reported rarely in children. To date, 10 cases are documented in the English-language literature. This study, based on 13 biopsies from 11 HIV-positive children (9 males, 2 females), documents the clinicopathologic features of PBL. The CD4 count ranged from 9 to 800 cells/mm3. All biopsies demonstrated exclusive plasmablastic morphology; CD20 immunonegativity; and VS38c, EMA, CD31, MUM-1, CD45, and CD79a immunopositivity. B-cell monoclonality was confirmed in all biopsies. Of 3 biopsies subjected to FISH investigation, 2 had a t(8,14) translocation. Nine patients with follow-up details were treated exclusively with HAART (highly active antiretroviral therapy) or with combinations of HAART, chemotherapy, and radiotherapy. Seven patients died. PBL histomorphology, disease stage, and treatment modalities employed were not predictive of outcome. The survival of 2 stage 4 patients for 3 and 8 years each, managed on HAART, chemotherapy, and radiotherapy, however, may justify a role for combined therapeutic modalities for PBL.

Subcutaneous palisading granulomatous pseudocysts of Echinococcus granulosus origin

Background:  Palisading granulomatous reactions are documented in many diseases. Although subcutaneous cystic echinococcosis (CE) is documented rarely, a subcutaneous palisading, granulomatous, pseudocystic (PGP) reaction to elusive Echinococcus granulosus membranous components, in the absence of cutaneous fistulisation, is undocumented.

Granulomas in acquired immunodeficiency syndrome-associated cutaneous Kaposi sarcoma: evidence for a role for Mycobacterium tuberculosis.

Background: Co‐lesional acquired immunodeficiency syndrome‐associated cutaneous Kaposi sarcoma (AIDS‐KS) and Mycobacterium tuberculosis‐associated granulomatous inflammation are undocumented.