Showing papers by "Robert P. Hasserjian published in 2008"
TL;DR: It is concluded that the panenteritis associated with injection of α-CTLA-4 mAbs demonstrates histology resembling autoimmune enteropathy, and it is suspected that the increased number of regulatory T cells in the gastrointestinal mucosa may play a role in the pathogenicity.
Abstract: Monoclonal antibodies (mAbs) against the cytotoxic T lymphocyte antigen-4 (CTLA-4) molecule are used as an adjuvant to experimental tumor immunization protocols in the treatment of malignant melanomas and ovarian cancers. Aside from noted early therapeutic successes, a spectrum of adverse effects, including severe gastroenteritis, has been reported. We report herein our observations of 5 patients who developed severe gastrointestinal toxicity affecting the gastric, small intestinal, and colonic mucosa. The endoscopic findings were variable, ranging from normal to diffusely erythematous and ulcerated mucosa. The constant histologic findings included a lymphoplasmacytic expansion of the lamina propria with increase in intraepithelial lymphocytes. Increased epithelial apoptosis was also a distinctive feature. Cryptitis and glandular inflammation were observed in the colon, ileum, and stomach, whereas villous blunting was present in the ileal and duodenal mucosa. Immunohistochemical analysis revealed a marked increase of all T-cell subsets (CD3+, CD4+, and CD8+) and of CD4CD25 regulatory T cells. We conclude that the panenteritis associated with injection of alpha-CTLA-4 mAbs demonstrates histology resembling autoimmune enteropathy. Furthermore, although the pathogenesis of immune dysregulation after the infusion of alpha-CTLA-4 mAbs remains unclear, we suspect that the increased number of regulatory T cells in the gastrointestinal mucosa may play a role in the pathogenicity.
130 citations
TL;DR: It is concluded that in erythroid-predominant myelodysplastic syndrome, blast calculation as a proportion of marrow nonERYthroid rather than total nucleated cells can better stratify patients into prognostically relevant groups.
42 citations
TL;DR: Two recent studies describing a CD4+CD8+ (double-positive) T-cell population in nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) suggest that flow cytometry could play a role in the diagnosis of this Hodgkins lymphoma subtype.
Abstract: Hodgkin lymphomas are characterised by the presence of rare malignant cells in a background of non-neoplastic inflammatory cells. Flow cytometric analysis of involved tissues is generally not thought to be useful in establishing the diagnosis, because of the small number of neoplastic cells present. However, two recent studies describing a CD4+CD8+ (double-positive) T-cell population in nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) suggest that flow cytometry could play a role in the diagnosis of this Hodgkin lymphoma subtype. In addition, awareness of this unusual T-cell population is important in avoiding a misdiagnosis of a T-cell neoplasm. Although the function of CD4+CD8+ T-cells in NLPHL is not known, studies of phenotypically similar cells in other settings point to a reactive or regulatory role. CD4+CD8+ T-cells have also been identified in the benign entity progressive transformation of germinal centres (PTGC), suggesting a possible relationship between NLPHL and PTGC.
31 citations
TL;DR: A combination of excellent diagnostic samples, appropriate ancillary tests, and knowledge of the clinical context provides the best background to distinguish between the common reactive and neoplastic processes that involve the bone marrow and to avoid diagnostic pitfalls in making these distinctions.
Abstract: Examination of the bone marrow poses several unique challenges to the pathologist: it is a semisolid organ without helpful gross correlation, it exists in a dynamic state with the peripheral blood and other organs of the lymphohemopoietic system, and the diagnosis of diseases affecting bone marrow often depends heavily on ancillary special studies. The bone marrow examination ideally encompasses review of the bone marrow biopsy histology (with or without additional nondecalcified clot preparation material), bone marrow aspirate smear cytology, and the peripheral blood smear; optimal procurement and processing of these samples is critical in ensuring that a maximal level of diagnostic information can be extracted. The pathologist must be aware of the clinical context of the bone marrow and the results of ancillary tests, whether these are ordered by the pathologist or the clinician. A combination of excellent diagnostic samples, appropriate ancillary tests, and knowledge of the clinical context provides the best background to distinguish between the common reactive and neoplastic processes that involve the bone marrow and to avoid diagnostic pitfalls in making these distinctions.
17 citations
TL;DR: A 33-year-old man was admitted to the hospital with fever, abdominal pain, and pancytopenia 15 years after renal transplantation, and imaging studies disclosed hepatosplenomegaly.
Abstract: A 33-year-old man was admitted to the hospital with fever, abdominal pain, and pancytopenia 15 years after renal transplantation. Imaging studies disclosed hepatosplenomegaly. A diagnostic procedure was performed.
10 citations
TL;DR: MRI scans of the brain showed symmetric abnormalities involving the temporal lobes, left basal forebrain, and insular regions and a CT scan of the chest disclosed an anterior mediastinal mass.
Abstract: A 65-year-old right-handed man was transferred to this hospital because of the recent onset of confusion and memory loss. MRI scans of the brain showed symmetric abnormalities involving the temporal lobes, left basal forebrain, and insular regions. A CT scan of the chest disclosed an anterior mediastinal mass. A diagnostic procedure was performed.
6 citations
TL;DR: There was no evidence that romiplostim exposure led to development of chronic idiopathic myelofibrosis or other clonal disorders in this small sample of patients, and increased reticulin was observed in the bone marrow of some romiplastim-treated patients and typically decreased soon after drug withdrawal.
5 citations