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G P Schechter

Publications and source records attributed to G P Schechter.

At least 37 records · Page 2Linked to original sources
PubMed1989

Dual parameter analysis of myeloma cells by flow cytometry. DNA content of cells containing monotypic cytoplasmic immunoglobulin.

Dual-parameter flow cytometric analysis of monotypic cytoplasmic immunoglobulin (CIg) and DNA content on 15 myeloma marrows allowed S-phase determination of the CIg(+) tumor separately from the CIg(-) hematopoietic cell pool. The median percentage of the CIg(+) cells in S-phase was 2% compared with 5% for the CIg(-) cells. The median survival of patients with more than 2%, and those with 2% or less CIg(+) S-phase cells was 2 months and more than 13 months, respectively, from the time of study. Ploidy analysis identified four patterns of plasma cell DNA content: entirely hyperdiploid, entirely diploid, combined diploid and tetraploid stemlines, and tumors containing diploid and aneuploid CIg(+) cells. A monotypic CIg(+) double stemline myeloma was distinguished from two aneuploid tumors containing admixed normal, diploid polyclonal plasma cells. This technique provides an improved and expedient means for determining the proliferating fractions of myeloma cells and enhances recognition of double stemline tumors and clonal evolution in myeloma.

Cytoplasm↗
PubMed1988

Histopathologic staging at initial diagnosis of mycosis fungoides and the Sézary syndrome. Definition of three distinctive prognostic groups.

STUDY OBJECTIVE: To determine the optimal staging evaluation at the time of initial diagnosis of mycosis fungoides or the Sézary syndrome. DESIGN: Retrospective review of a uniformly staged inception cohort. SETTING: Single-institution tertiary care center. PATIENTS: 152 consecutive patients who had mycosis fungoides with or without the Sézary syndrome within 6 months of the initial definitive diagnosis. INTERVENTION: A detailed staging evaluation including physical examination, routine laboratory studies, chest roentgenogram, lymphangiogram, peripheral blood smear, lymph node biopsy, bone marrow aspirate or biopsy, and liver biopsy in selected patients. MEASUREMENTS AND MAIN RESULTS: Univariate adverse prognostic features at initial diagnosis in patients with mycosis fungoides included (P less than 0.01) one or more cutaneous tumors or generalized erythroderma, adenopathy, blood smear involvement with Sézary cells, lymph node effacement, eosinophilia, and visceral involvement. Important, independent prognostic factors in a multivariate analysis are the presence of visceral disease and type of skin involvement. CONCLUSIONS: A staging system based on histopathologic evaluation of skin, lymph nodes, blood, and visceral sites provides more comprehensive prognostic information than clinical evaluation of skin disease and adenopathy. Patients may be divided at initial presentation into three prognostic groups: good-risk patients, who have plaque-only skin disease without lymph node, blood, or visceral involvement (median survival, greater than 12 years); intermediate-risk patients, who have cutaneous tumors, erythroderma, or plaque disease with node or blood involvement but no visceral disease or node effacement (median survival, 5 years); and poor-risk patients, who have visceral involvement or node effacement (median survival, 2.5 years).

Actuarial Analysis↗
PubMed1988

Hemolysis in sickle cell disease as measured by endogenous carbon monoxide production. A preliminary report.

To detect and quantitate temporal variations of the hemolytic rate in sickle cell disease, the authors measured endogenous carbon monoxide (CO) production in five normal subjects, nine patients with sickle cell anemia (SS) in steady clinical state, and two patients with sickle cell-hemoglobin C (SC) disease in and out of pain crises. The red blood cell life span calculated from these data (RCLSco) ranged from 81.2 to 102.9 days (mean +/- standard deviation [SD] 88.0 +/- 9.2, coefficient of variation [CV] 10.2%) for the normal subjects and 8.0-24.7 days (mean +/- SD 12.1 +/- 5.1, CV 42.1%) for those with SS. Although the individual figures for RCLSco for the normal subjects and those with SS fell within the range previously obtained by radioisotopic techniques for the respective groups, the mean values calculated from the CO technique were slightly (though not significantly) shorter for the normal subjects and about 25% shorter for the subjects with SS (P less than 0.01). Repetitive studies were performed in four subjects with SS who were clinically stable; the temporal variability in the calculated hemolytic rate differed considerably from patient to patient (CV 3.6%, 7.0%, 17.0%, 28.0%). In two patients concurrent RCLS studies were performed by the CO technique and 51Cr tagged red blood cells. In one patient, the RCLS was similar by the two techniques, in the other, a two exponent 51Cr curve did not permit calculation of RCLS. In the two patients with SC disease there was no difference in RCLSco during and after recovery from pain crisis. Although the CO technique may overestimate the turnover of circulating heme mass, especially in the presence of hemolysis, the results of serial studies in a small number of patients with SS suggest but do not prove temporal variations in hemolytic rate in SS.

Anemia, Sickle Cell↗
PubMed1988

The beta subunit of the interleukin-2 receptor mediates interleukin-2 induction of anti-CD3 redirected cytotoxic capability in large granular lymphocytes.

The interleukin 2 (IL 2) receptor was studied in three cases of large granular lymphocyte (LGL) lymphocytosis. All cases were nonreactive with anti-Tac monoclonal antibody (MoAb; recognizing the p55 alpha subunit of the IL 2 receptor). Sodium dodecyl sulfate (SDS)/polyacrylamide gel electrophoretic analysis (PAGE) of cells to which radio-labeled rIL 2 had been chemically crosslinked revealed uniform expression of the p70/75 beta subunit of the IL 2 receptor in the absence of the alpha subunit. Stimulation of this receptor with 2 nmol/L rIL 2 for five days led to acquisition of anti-CD3 redirected cytotoxicity. This was accompanied by a fivefold to tenfold elevation in the activity of intracellular N-alpha-benzyloxycarbonyl-L-lysine thiobenzyl esterase, an LGL granule marker enzyme. These effects of IL 2 did not require induction of the Tac peptide.

Antigens, Surface↗
PubMed1988

Cytogenetic studies in patients with secondary leukemia/dysmyelopoietic syndrome after different treatment modalities.

Cytogenetic studies of 68 patients who developed secondary leukemia (SL)/dysmyelopoietic syndrome (DMS) after extensive chemotherapy and/or radiation therapy as well as patients who developed SL/DMS without such treatment showed that those patients who received radiation alone or with chemotherapy had more extensive numerical and structural abnormalities than those who received only chemotherapy. In terms of the specific chromosomal abnormalities, there are no differences between the various treatment groups. Hypodiploidy is the most common form of aneuploidy in these patients, with the most common numerical abnormality being the loss of chromosome 7. The most common structural abnormalities involved chromosomes 3 and 5. When compared with patients with de novo leukemia and DMS, the chromosomal abnormalities in these patients are more complex and extensive. Serial studies revealed that cytogenetic abnormalities do not precede the development of hematologic changes by significant time periods.

Antineoplastic Agents↗
PubMed1987

Cytologic transformation in cutaneous T cell lymphoma: a clinicopathologic entity associated with poor prognosis.

The clinical course of cutaneous T cell lymphoma (mycosis fungoides and Sezary syndrome) is generally indolent, but in occasional patients becomes fulminant. We found that biopsies from patients with accelerating disease can reveal cytologic transformation from previously observed small, convoluted lymphocytes to large cells that are similar to cells seen in large-cell lymphoma. The cerebriform nuclei characteristic of malignant T cells can only rarely be identified. Of 150 cutaneous T cell lymphoma patients we treated from 1976 to 1984, cytologic transformation was identified in 12 after review of peripheral blood smears and biopsies from skin, lymph nodes, and visceral sites. Patients who developed cytologic transformation were initially characterized by advanced stage (11 of 12), with lymph node effacement (seven of 11) and erythroderma (five of 12). The tumor cell DNA content after transformation was aneuploid (four of four), and the ability to form rosettes with sheep erythrocytes was retained in transformed cells (three of three). The median time from diagnosis of cutaneous T cell lymphoma to cytologic transformation was 21.5 months (range, 4 to 64), and the median survival from transformation was only 2 months (range, 0 to 19+). We conclude that cytologic transformation in cutaneous T cell lymphoma represents a distinct clinicopathologic entity, characterized by an aggressive clinical course.

Biopsy↗
PubMed1987

Evaluation of circulating malignant cells provides prognostic information in cutaneous T cell lymphoma.

Peripheral blood lymphocyte morphology was evaluated prospectively by light microscopy of blood smears and E rosette preparations in 160 patients with cutaneous T cell lymphoma (CTCL). Blood involvement was related to the type of cutaneous T-stage, being present in 90% of patients with erythroderma (T4), 27% of those with cutaneous tumors (T3), 9% of those with generalized (T2), and 0% of those with limited skin plaques (T1). Untreated patients with blood involvement (38 of 105) had a higher frequency of CTCL in lymph nodes and viscera and survival inferior to that of patients with normal or nondiagnostic lymphocyte morphology (P less than .001). Multivariate analysis showed skin stage and age to be the most important pretreatment risk factors for survival. Although blood involvement was not an independent risk factor for the entire group, it appeared to have some adverse influence in the T2/T3 subsets (P = .051). Both lymphocytosis and size distribution of the circulating CTCL cells at initial diagnosis influenced survival. Patients with "mixed cell" cytology (greater than 20% large [greater than 11 microns] CTCL cells), had a worse survival than those with predominantly small circulating CTCL cells (P = .009). The former were more likely to have aggressive features, including lymph node effacement by tumor (P less than .001) and visceral disease (P = .074), than were "small cell" patients. Our data indicate that detailed review of the blood lymphocyte morphology in patients with diagnosed or suspected CTCL is helpful in predicting extent of disease and prognosis.

Age Factors↗
PubMed1986

Combined modality treatment of cutaneous T cell lymphoma: results of a 6-year follow-up.

Thirty-nine patients with cutaneous T cell lymphoma (CTCL; including mycosis fungoides or the Sezary syndrome) with no previous treatment other than topical therapy or oral corticosteroids, received total skin electron beam irradiation (TSEB) and either sequential or simultaneous systemic chemotherapy. Median follow-up, measured from the time of initiation of therapy to the time of analysis, is in excess of 6 years and extends to 100+ months. Thirteen patients with stage I disease (limited to skin with no adenopathy) received 3,000 rad total skin electron beam irradiation followed by three 2-week courses of daily intravenous (IV) mechlorethamine. Twenty-six patients with advanced disease (stage II-IV) received 2,400 rad of TSEB and simultaneous chemotherapy with two alternating three-drug regimens: vinblastine, doxorubicin, and bleomycin (VAB) alternating with cyclophosphamide, methotrexate, and prednisone (CMP) administered over 54 weeks. The overall response rate was 92% with 16 of 39 patients (41%) achieving a histologically documented complete response (CR). Stage I patients had a significantly increased CR rate (77%) compared with stage II-IV (P less than .01). The overall 6-year survival was 92% for stage I patients and 26% for stage II-IV patients (23%) (P less than .001). Among ten completely responding stage I patients, six remain alive and disease-free in excess of 72 months. The median disease-free survival is 26 months for completely responding stage II-IV patients (P = .04), but none are continuous disease-free survivors after protocol treatment. We conclude that combined modality treatment can be safely administered and produces prolonged disease-free survival in some stage I patients, but not in more advanced stage patients.

Adult↗
PubMed1986

Nephrotic syndrome associated with a clonal T-cell leukemia of large granular lymphocytes with cytotoxic function.

A 51-year-old man presented with a T-cell leukemia of large granular lymphocytes and rapidly developed a nephrotic syndrome due to presumptive minimal-change glomerulopathy. The E-rosette+, Ia+ cells demonstrated cytotoxic activity similar to that of natural killer lymphocytes but lacked other T-subset markers, except that one third of them bore Fc(IgG) receptors. Cytogenetic analysis revealed loss of chromosome 10 and the translocation (1;10)(p11;q11) in all metaphases. Regression of the leukemia after chemotherapy was accompanied by a dramatic resolution of the nephrotic syndrome, suggesting that the activated granular lymphocytes induced the renal lesion. The close association of a clonal T-lymphoproliferative disorder with minimal-change nephrotic syndrome lends further support to current views implicating activated T cells or their products in the pathogenesis of this glomerulopathy.

Chromosomes, Human, 1-3↗
PubMed1985

Histologic assessment of lymph nodes in mycosis fungoides/Sézary syndrome (cutaneous T-cell lymphoma): clinical correlations and prognostic import of a new classification system.

Mycosis fungoides and the Sézary syndrome share common cutaneous histopathologic features, and this spectrum of malignant disease is referred to here as cutaneous T-cell lymphoma (CTCL). A method (LN classification) for describing the histopathologic features of lymph nodes in CTCL is presented. In this system, lymph node biopsy specimens are scored according to the number of atypical lymphoid cells in T-cell-dependent paracortical zones and the preservation or distortion of the lymph node architecture. Lymph node architecture is preserved in lymph nodes scored LN1 to LN3, and these nodes may have coexistent dermatopathic change. LN1 nodes have single infrequent atypical lymphocytes in paracortical T-cell regions. LN2 nodes have small clusters of paracortical atypical cells. LN3 nodes have large clusters of atypical cells. LN4 nodes are partially or totally effaced by atypical cells. This system was used to classify 96 lymph node biopsy specimens obtained within six months of the initial diagnosis of CTCL; no LN1 nodes, 37 LN2, 44 LN3, and 15 LN4 nodes were found. The LN class was significantly correlated with the extent of skin, blood, and visceral involvement, as well as with survival. Patients with LN2 lymph nodes have an estimated five-year survival of 70 per cent, while patients with LN3 and LN4 nodes have estimated five-year survivals of 30 and 15 per cent, respectively. The survival differences between the LN subgroups were all significant (P less than 0.05). The LN classification system was clearly shown to be reproducible among experienced pathologists. The LN system for the histopathologic classification of lymph nodes in CTCL is of prognostic value and should be used to assess lymph node biopsies in patients with CTCL.

Humans↗
PubMed1985

Recombinant leukocyte A interferon in B-cell chronic lymphocytic leukemia: in vivo effects on autologous antitumor immunity.

Eight previously treated and four untreated patients with B cell chronic lymphocytic leukemia (CLL) received 20 X 10(6) U/m2 recombinant leukocyte interferon clone A (rIFN-alpha A) intramuscularly three times a week for 8 weeks. None of the eight patients who had received prior chemotherapy exhibited objective evidence of tumor regression. Two of the four previously untreated patients responded with transient (90%) decreases in absolute lymphocyte counts lasting for 2 and 7 months. Toxicity was moderate, with all patients experiencing a flu-like syndrome requiring a 50% dose reduction. Half of the patients exhibited anorexia, weight loss, and a drop in performance status. The two responders had normal serum immunoglobulin levels prior to treatment, whereas 80% of non-responders had depressed levels. Treatment with rIFN-alpha A was associated with a depression of nonspecific and specific humoral immunity in assays employing cryopreserved autologous pretherapy CLL cells. No consistent effects were demonstrable in cytolytic assays with purified peripheral blood T cells as effector cells, including one that utilized autologous CLL target cells. rIFN-alpha A has limited antitumor activity in B cell CLL which is restricted to untreated patients with an early stage of disease. With the assays employed it was not possible to demonstrate that rIFN-alpha A could augment autologous antitumor immunity.

Aged↗
PubMed1984

Therapy for multiple myeloma with alternating non-cross-resistant chemotherapy combinations: heterogeneity of tumor responsiveness.

Thirty-five previously untreated patients with multiple myeloma were treated with a 60-week course of alternating, potentially non-cross-resistant chemotherapy combinations (melphalan and prednisone; vincristine, cyclophosphamide, doxorubicin, and prednisone; and carmustine, melphalan, and prednisone), alternating every 15 weeks in an attempt to prevent the development of drug resistance. The overall objective response rate (greater than 50% decrease in M protein) was 60% and six patients (17%) had a complete disappearance of the M protein. After 60 weeks, chemotherapy was discontinued in 17 responding or stable patients until relapse occurred from 4 to 39 months later (median, 12 months). Patients relapsing late (greater than 12 months after discontinuation of therapy) responded more frequently than those relapsing earlier to the reinstitution of the same chemotherapy program. The overall response rate and the actuarial median survival of 26 months in the 35 patients do not differ from the results reported recently with nonalternating combinations given until clinical tumor progression. The failure of this study to prolong survival by using alternating regimens may be due to (a) the likely possibility that the initial two regimens are not actually non-cross-resistant in most myeloma patients, and (b) the long interval between the alternating regimens, particularly in the face of the low response rate to the initial regimen of melphalan and prednisone.

Adult↗
PubMed1983

Clinical course of retrovirus-associated adult T-cell lymphoma in the United States.

We studied the clinical features of 11 patients with adult T-cell lymphoma associated with the human T-cell lymphoma virus. The patients were predominantly young, black, and born in the southeastern United States. They had an aggressive course, with the rapid onset of disseminated skin lesions or symptoms related to hypercalcemia and other metabolic disturbances, or both. Common findings included rapid enlargement of peripheral, hilar, and retroperitoneal lymph nodes, with sparing of the mediastinum; invasion of the central nervous system, lungs, or gastrointestinal tract; and opportunistic infections. A paraneoplastic syndrome characterized by increased bone turnover, abnormal bone scintigraphy, and hypercalcemia was present in all patients. Intensive combination chemotherapy produced prompt complete clinical remissions, which were generally of short duration. Similar features have been described in patients in Japan and the West Indies who had adult T-cell lymphoma, which is also associated with the human T-cell lymphoma virus. This syndrome should be suspected in patients presenting with the acute onset of widespread T-cell lymphoma in association with metabolic bone disease and hypercalcemia. The presence of the syndrome can be confirmed by appropriate serologic and virologic studies.

Adult↗
PubMed1983

The human T-cell leukemia/lymphoma virus, lymphoma, lytic bone lesions, and hypercalcemia.

The human T-cell lymphoma (HTL) virus is a type C RNA tumor virus isolated from patients with malignancies of mature T cells. We report three patients with peripheral T-cell lymphoma, hypercalcemia, and antibodies to HTL virus. One patient presented with idiopathic hypercalcemia of 6 months' duration, two with striking lytic bone lesions, and two with circulating malignant lymphocytes. Malignant cells from all patients had surface markers characteristic of thymic-derived lymphocytes (T cells), and all patients had natural serum antibodies to disrupted HTL virus and to one or both viral structural proteins p19 and p24. Patients with adult peripheral T-cell lymphomas, particularly those that present with hypercalcemia and lytic bone lesions, may have antibodies to the type C RNA human tumor virus, HTL virus.

Adult↗
PubMed1982

Erythroleukemia and other hematologic complications of intensive therapy in long-term survivors of small cell lung cancer.

Eight patients with small cell bronchogenic carcinoma treated with intensive combination chemotherapy, with and without radiotherapy, have been followed for a minimum of two and a half years without relapse. One patient, after a prodrome of macrocytic sideroblastic anemia, leukopenia, and thrombocytopenia, experienced erythroleukemia 34 months after starting chemotherapy, and cytogenetic studies revealed extensive chromosomal abnormalities. Another patient had persistent macrocytic anemia and pancytopenia two years after cessation of therapy. The remaining six patients had normal peripheral blood smears and cell counts. A significant incidence of preleukemia syndromes and acute leukemia appearing as late complications in intensively treated small cell lung cancer patients requires confirmation in larger series of long-term survivors. Prospective determination of marrow karyotype abnormalities may help to identify patients at greatest risk for developing secondary leukemia.

Aged↗