Biomedical subjects

R N Miranda

Publications and source records attributed to R N Miranda.

15 recordsLinked to original sources

PubMed1999

Somatic mutation analysis of IgH variable regions reveals that tumor cells of most parafollicular (monocytoid) B-cell lymphoma, splenic marginal zone B-cell lymphoma, and some hairy cell leukemia are composed of memory B lymphocytes.

The cell of origin of parafollicular (monocytoid) B cell lymphoma (PBCL), splenic marginal zone lymphoma (SMZL), and hairy cell leukemia (HCL) is controversial. To better understand the relationship between these low-grade B-cell neoplasms, we analyzed the nucleotide sequences of the rearranged immunoglobulin heavy (IgH) chain variable (V) region of the clonal population of cells in five cases of PBCL, four cases of SMZL, and seven cases of HCL to determine whether these neoplasms could be differentiated by the degree of somatic mutation in the IgH V gene or by the IgH V gene family usage. DNA was extracted from diagnostic material and clonality confirmed by PCR. The DNA was reamplified using V heavy chain family specific primers, and the amplicons were sequenced. Sequences were compared with germline IgH V gene sequences, and base changes were determined to be silent or to represent amino acid replacements by using three different methods. Four of five (80%) cases of PBCL, three of four (75%) cases of SMZL, and three of seven (43%) cases of HCL showed evidence of antigen selection, suggesting that these neoplasms involved clonal expansions of postgerminal center memory lymphocytes. Only SMZL showed a preferential usage of V(H)1 family genes.

Adult↗

PubMed1996

Chronic myeloid leukemia manifested during megakaryoblastic crisis.

We describe a 38-year-old man with a chronic myeloproliferative syndrome characterized by elevated white blood cell and platelet counts and increased blasts in the peripheral blood. Bone marrow aspiration was a "dry tap" and the biopsy specimen was hypercellular with numerous blasts, atypical megakaryocytes, and increased reticulin fibrosis. The blasts exhibited cytochemical reactivity for nonspecific esterase and PAS and immunohistochemically were positive for factor VIII, supporting megakaryoblastic lineage. Cytogenetic studies of peripheral blood revealed the t(9;22)(q34;q11). We interpreted these findings to be most consistent with chronic myeloid leukemia (CML) manifested at the time of megakaryoblastic crisis. Although the initial complete blood count showed leukocytosis and thrombocytosis, the patient subsequently had pancytopenia with clinical and pathologic findings consistent with acute myelofibrosis (AMF). Cytosine arabinoside and etoposide chemotherapy induced remission of the acute leukemia. We conclude that CML infrequently presents itself in megakaryoblastic crisis and that such cases may result in the clinicopathologic syndrome of AMF. The success of chemotherapy in this case also suggests that intensive antileukemic therapy may be useful in other patients with either CML-blast crisis or the clinicopathologic syndrome of AMF.

Adult↗

PubMed1996

Stage IE non-Hodgkin's lymphoma involving the dura: A clinicopathologic study of five cases.

OBJECTIVE AND DESIGN: Non-Hodgkin's lymphomas rarely present as a localized mass involving the dura. In this report we describe the clinical, histologic, and immunohistochemical features of five cases of stage IE non-Hodgkin's lymphoma involving the dura. PATIENTS: Four women and one man, 36 to 67 years of age (median 50.6 years). RESULTS: Myelography and magnetic resonance imaging scans revealed discrete expansile masses involving the dura of the cervical, thoracic, and lumbar regions of the spinal cord and the frontal lobe of the brain. Histologically, the tumors were classified in the Working Formulation as small lymphocytic (2), diffuse large cell (2), and large cell immunoblastic (1) (anaplastic large cell lymphoma). Four tumors were of B-cell lineage and the anaplastic large-cell lymphoma was of T-cell lineage. The two small lymphocytic neoplasms had immunoglobulin heavy-chain gene rearrangements as shown by either Southern blot hybridization or the polymerase chain reaction. Four patients underwent decompression laminectomy; three received spinal radiation; two received chemotherapy (one intrathecal, one systemic) for lymphocytosis of the cerebrospinal fluid. The dural mass overlying the frontal lobe was excised and focally irradiated. Clinical follow-up was available for all patients. Four patients were alive 12 to 40 months after diagnosis and showed no evidence of recurrent or disseminated disease. The patient with anaplastic large-cell lymphoma died 10 days after laminectomy, secondary to pulmonary thromboemboli. CONCLUSIONS: We conclude that non-Hodgkin's lymphomas of varied histologic types and of either B- or T-cell lineage may rarely present as a stage IE dural mass. These lesions appear to have a good initial response to treatment; however, longer clinical follow-up is necessary to assess the incidence of relapse and final outcome.

Adult↗

PubMed1996

Peritoneal silicosis.

A 73-year-old man with a clinical diagnosis of pulmonary silicosis (long-standing exposure to silica, pulmonary infiltrates, and flu-like symptoms) presented to the emergency room with fever, acute biliary colic, and cholelithiasis. The patient had a 2-year status postchemotherapy with complete remission of hepatic and splenic malignant lymphoma. At laparotomy we found studding of the undersurface of the diaphragm with multiple small dark nodules. Owing to the patient's history of previously treated abdominal malignant lymphoma, the lesions were grossly interpreted as abdominal lymphomatosis. The microscopic appearance of the lesions suggested silicotic nodules, which were confirmed by digital scanning electron microscopy and roentgenographic microanalysis performed on formalin-fixed, paraffin-embedded tissue. This is an unusual extrapulmonary pattern of peritoneal seeding in silicosis.

Aged↗

PubMed1995

Fatal acute pancreatitis caused by valproic acid.

We describe a case of a 31-year-old woman with cerebral palsy who developed fatal acute hemorrhagic pancreatitis while being treated with valproic acid to control her seizure activity. Acute pancreatitis is usually due to alcohol ingestion or biliary tract disease, and unusual causes include trauma, metabolic diseases, or drugs. Valproic acid is considered a safe drug, although rare cases of severe toxicity such as hepatitis and acute pancreatitis, including two fatalities, have been reported. Our review of the literature revealed that most patients who developed acute pancreatitis had serum levels of the drug within the therapeutic range, and most of the cases occurred either secondary to a recent increase in the dose or to initiation of treatment. It also appeared that the fatalities occurred due to a delayed diagnosis of acute pancreatitis, either resulting from an unsuspected diagnosis or to the deteriorated mental status of the patients receiving the drug, which precluded their ability to elaborate symptomatology. We believe that early diagnosis and withdrawal of the drug are significant factors determining the course of valproic-acid-associated pancreatitis.

Acute Disease↗

PubMed1995

Composite follicular variant of papillary carcinoma and mucoepidermoid carcinoma of the thyroid. Report of a case and review of the literature.

The follicular variant of papillary carcinoma of the thyroid gland is a commonly recognized, well-defined entity. However, primary mucoepidermoid carcinoma of the thyroid is rare, with only 21 cases reported. We describe a 29-year-old woman who presented with a mass in the right lobe of the thyroid. The tumor was classified as the follicular variant of papillary carcinoma of the thyroid with several foci of mucoepidermoid carcinoma. Both components were invading the capsule and had spread to regional lymph nodes. This is the first reported case in which both the papillary and mucoepidermoid carcinomas were present in the primary tumor and in the metastases.

Adult↗

PubMed1995

Amyloid in adrenal gland pheochromocytomas.

OBJECTIVE: To assess the frequency of amyloid deposits in adrenal gland pheochromocytomas. DESIGN: We evaluated 22 pheochromocytomas using routine hematoxylin-eosin and Congo red stains, polarization microscopy, and electron microscopy. Cases with amyloid were further characterized immunohistochemically. RESULTS: Congo red and polarization microscopy revealed characteristic apple-green birefringence, not abolished by potassium permanganate incubation, in only one neoplasm. In a subset of the remaining tumors, yellow or yellow-green birefringence not characteristic of amyloid was found. We performed electron microscopy on the tumor with characteristic apple-green birefringence and six other neoplasms with abundant yellow or yellow-green birefringence. Amyloid was identified in two tumors, including the Congo red-positive tumor, while the remaining five neoplasms contained collagen. Immunohistochemically, the amyloid deposits were reactive with component P and immunoglobulin kappa- and lambda-light chains in both tumors. Adsorption studies using human urine with monoclonal immunoglobulin kappa- or lambda-light chains abolished reactivity, consistent with specific immunostaining for both light chains. Transthyretin was present in one tumor. The neoplastic cells expressed chromogranin, neuron-specific enolase, and [Leu5]-enkephalin, although the amyloid was not reactive. CONCLUSIONS: We conclude that amyloid is infrequent in pheochromocytomas. Electron microscopic examination is more sensitive than Congo red stain and, in our opinion, is the best technique for the demonstration of amyloid deposits.

Adrenal Gland Neoplasms↗

PubMed1994

Systemic mast cell disease presenting with peripheral blood eosinophilia.

Patients with mast cell disease most frequently present with skin lesions (urticaria pigmentosa), with systemic involvement in many cases. However, a small subset of patients with systemic mast cell disease lacks skin lesions and, in these patients the correct diagnosis may be difficult to establish. Patients with systemic mast cell disease commonly have hematologic abnormalities, including eosinophilia in up to 20% of cases, but isolated eosinophilia has been reported rarely. We describe an 82-year-old woman who was admitted to Rhode Island Hospital for coronary artery disease and unstable angina. Incidentally, an absolute eosinophil count of 7.84 x 10(9)/L (normal, < 0.45 x 10(9)/L) was detected with moderate thrombocytopenia and mild anemia. Review of earlier records revealed that absolute eosinophilia had been present for approximately 4 months, initially without other hematologic abnormalities. Clinical work-up showed left upper quadrant tenderness. No skin lesions were identified. Bone marrow core biopsy revealed paratrabecular, perivascular, and medullary mast cell aggregates with eosinophils, suggestive of mast cell disease. At autopsy the diagnosis was confirmed. Mast cell aggregates were found in the liver, spleen, lymph nodes, and bone marrow, and chloroacetate esterase stain highlighted mast cell granules. The bone marrow was also hypercellular with granulocytic and eosinophilic hyperplasia, suggestive of a poorly defined myeloproliferative disorder. Patients with systemic mast cell disease initially may present with peripheral eosinophilia. Clinical suspicion of the diagnosis facilitates proper handling of the bone marrow core biopsy specimen to allow the demonstration of mast cell granules.

Aged↗

PubMed1994

Fluorescent in situ hybridization in routinely processed bone marrow aspirate clot and core biopsy sections.

Fluorescent in situ hybridization (FISH) is a technique which complements conventional cytogenetic banding analysis by allowing the evaluation of cells in interphase as well as metaphase. This technique has been used to study air-dried peripheral blood and bone marrow aspirate smears. We have applied the FISH technique to study routinely processed sections of bone marrow aspirate clot and decalcified core biopsy specimens, fixed in either formalin or B5 and embedded in paraffin. We evaluated 28 specimens (8 aspirate clot and 20 core biopsy sections) for chromosome 8 copy number, studied previously by conventional cytogenetics, and found the following distribution: 15 with disomy, 11 with trisomy, and 2 with tetrasomy. Using a chromosome 8 alpha-satellite probe, we detected fluorescent hybridization signals in 18 of 28 specimens (64%); 6 of 8 (75%) aspirate clot sections, and 12 of 20 (60%) core biopsy sections. Ten of 13 (77%) B5-fixed and 8 of 15 (53%) formalin-fixed specimens had hybridizing signals. Specimen age was a significant factor; 10 of 11 (91%) specimens processed within the last 6 months showed signals, in contrast with 8 of 17 (47%) specimens older than 6 months. In the positive specimens, 200 cells were analyzed in areas where individual cells could be identified. In the disomic specimens, two signals per cell were seen in 34 to 66% of the cells. Rare cells (0-2%) with three signals were detected. In the trisomic specimens, three signals per cell were seen in 19 to 46% of the cells. In the tetrasomic specimens, four signals per cell were seen in 15 to 25% of the cells. We conclude that the FISH technique may be useful in the detection of numerical chromosomal abnormalities such as trisomy and tetrasomy 8 in routinely processed bone marrow aspirate clot and decalcified core biopsy sections.

Biopsy, Needle↗

PubMed1974