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G P Schechter

Publications and source records attributed to G P Schechter.

At least 19 recordsLinked to original sources
PubMed1992

Prognostic implications of evaluation for lymph node involvement by T-cell antigen receptor gene rearrangement in mycosis fungoides.

We investigated the correlation between the detection of clonal rearrangement of the T-cell antigen receptor gene (TCRR) in lymph node tissue with histopathologic lymph node classification in 33 patients with mycosis fungoides with and without the Sezary Syndrome. We analyzed DNA extracted from lymph nodes that were histologically uninvolved (LN1-2), dermatopathic nodes with clusters of atypical cells (LN3), and nodes effaced with lymphoma (LN4) and found TCRR in none of five LN1-2 nodes, 8 of 17 LN3 nodes, and 10 of 11 LN4 nodes. Further, the detection of TCRR correlated with presence of palpable adenopathy (P2 less than .0001) and was associated with a worse survival (P2 = .0024). Within the subgroup of patients with LN3 nodes, there was a trend (P2 = .14) toward inferior survival if nodes were involved by TCRR, irrespective of extent of skin disease. We conclude that detection of TCRR in nodes from mycosis fungoides patients is an objective and reliable means of assessing tumor infiltration of lymph node and is associated with an inferior survival.

Blotting, Southern↗
PubMed1992

Phase II study of pentostatin and intermittent high-dose recombinant interferon alfa-2a in advanced mycosis fungoides/Sézary syndrome.

PURPOSE: This phase II study was undertaken to assess the efficacy and toxicity of alternating administration of pentostatin (deoxycoformycin [DCF]) and interferon alfa-2a (IFN) in patients with advanced or refractory mycosis fungoides (MF) or the Sézary syndrome (SS). PATIENTS AND METHODS: Forty-one patients underwent therapy with alternating cycles of DCF 4 mg/m2 intravenously (IV) days 1 through 3 and IFN 10 million U/m2 intramuscularly (IM) day 22, and 50 million U/m2 intramuscularly (IM) days 23 through 26. Twenty-nine patients had not responded to prior chemotherapy or total-skin electron-beam irradiation (TSEB), six had not responded to topical therapies, and six had no previous treatment. RESULTS: Two patients achieved a complete response (CR) and 15 achieved a partial response (PR), for an overall response rate of 41% (95% confidence interval, 26% to 58%). No responses were observed in the seven patients with visceral involvement. The median progression-free survival of patients who responded was 13.1 months. IFN-related constitutional symptoms were reported in 39% of patients; severe toxicities included cardiomyopathy in one patient, acute and chronic pulmonary dysfunction in four, and reversible mental status changes in two. Seven patients developed herpes zoster during therapy and six had staphylococcal bacteremia. CONCLUSION: These results suggest that the combination of DCF and IFN is an active regimen in MF patients without visceral involvement.

Adult↗
PubMed1991

Clonal rearrangement of the T-cell receptor beta-chain gene in hyperplastic lymphadenopathy associated with lung cancer.

A patient presenting with marked inflammatory lymphadenitis and Jaccoud's arthritis was found to have a rearranged gene for the beta-chain of the T-cell receptor (TCR-beta) antigen in the lymph node DNA digests and normal germ line DNA in the peripheral blood lymphocytes. Four months later, the patient was diagnosed to have poorly differentiated adenocarcinoma of the lung with small foci of metastatic tumor in lymph nodes that contained the same extensive lymphocytic and inflammatory cell infiltrates noted earlier. Rearranged TCR-beta chain genes were detected in both lymph node and peripheral blood lymphocyte DNA at this time. The most likely explanation for the florid lymph node reaction and the unusual arthropathy appears to be a paraneoplastic immune response. The rearranged TCR-beta genes indicate a clonal T-cell expansion that most likely resulted from the aberrant immunologic response to the lung cancer.

Aged↗
PubMed1990

Differential response of malignant human B-cells to anti-IgM immunoglobulin (anti-mu) and B-cell growth factor: unique direct cytotoxicity of anti-mu on prolymphocytic leukemia cells.

We examined in vitro tritiated thymidine uptake by B cells from seven prolymphocytic leukemia (PLL), seven chronic lymphocytic leukemia (CLL), and four plasma cell leukemia (PCL) patients in response to culture with anti-human IgM antibody (anti-mu) and B-cell growth factor (BCGF). In contrast to the stimulatory effect observed in normal B-cell cultures, the divalent F(ab')2 anti-mu antibody uniquely inhibited the autonomous proliferation and induced marked cytotoxicity in six of seven PLL cell cultures independent of complement or Fc-receptor-mediated mechanisms. There was neither stimulation or inhibition of the slgM+ CLL or the slgM- PCL cells. The inhibitory effect on the PLL cells was observed at an anti-mu concentration below the stimulatory threshold for normal B cells. Significant impairment of trypan blue exclusion was delayed until 48 hours, with morphological cellular changes suggestive of a programmed cell death mechanism or apoptosis. The cytotoxicity was independent of the slgM-staining intensity or the autonomous and BCGF-augmented DNA synthetic activity of the PLL cells and was similar in patients with de novo PLL or with prolymphocytic transformation of CLL. Cells from a PLL patient were separated by elutriation into two fractions, a BCGF-unresponsive large "transformed" cell fraction with marked autonomous DNA synthesis and a smaller lymphoid cell subset with low 3H-thymidine uptake that could be augmented by BCGF. Both fractions were equally susceptible to the cytotoxic effect of anti-mu. These data suggest that certain slgM-bearing malignant B cells are susceptible to anti-mu-triggered cytotoxicity. They may represent the malignant counterpart of a "tolerogenic" normal B-cell subset, and the unique direct cytotoxicity of anti-mu may provide a therapeutic strategy specifically for PLL.

Antibodies, Anti-Idiotypic↗
PubMed1990

B-cell surface phenotypes of proliferating myeloma cells: target antigens for immunotherapy.

Dual-parameter flow cytometric analysis of B-cell antigens and DNA content was used to determine the phenotypes of proliferating tumor cells (S-phase cells) from 30 patients with multiple myeloma. B4 (CD19), J5 (CALLA, CD10), B1 (CD20), and monotypic surface immunoglobulin (Slg) were expressed heterogeneously in 24 patients. J5 and monotypic Slg were found most frequently but were always expressed on a significantly lower percentage of cells than the antigens typically associated with plasma cells, cytoplasmic immunoglobulin (Clg) and T10 (CD38). S-phase cells were found in each antigen(+) subset. B antigen(+) cycling cells were demonstrated in 16 patients whose marrow or blood cells expressed B antigens exclusively in the hyperdiploid fraction and therefore were certainly part of the myeloma clone. Similar to the low level of proliferative activity of the T10(+), Clg(+), and PCA1(+) subsets, the percentages of cycling cells of the preplasma cell B-antigen-bearing myeloma subsets ranged from less than 1% to 12%. The tumor cells of four patients were also studied with dual-color surface antigen analysis and demonstrated independent expression of B antigens, with only rare coexpression of T10 and monotypic Slg, J5, or B4. These findings are consistent with the presence of distinct myeloma subsets bearing differing B phenotypes in the same tumor and provide evidence that the proliferation in myeloma is occurring at various developmental stages in the malignant B lineage. These antigens may be important targets for immunologic therapy aimed at eliminating the entire proliferating compartment of this B-cell tumor.

Antigens, Differentiation, B-Lymphocyte↗
PubMed1989

A randomized trial comparing combination electron-beam radiation and chemotherapy with topical therapy in the initial treatment of mycosis fungoides.

Mycosis fungoides is a T-cell lymphoma that arises in the skin and progresses at highly variable rates. Nonradomized studies have suggested that early aggressive therapy may improve the prognosis in this usually fatal disease. We studied 103 patients with mycosis fungoides, who, after complete staging, were randomly assigned to receive either combination therapy, consisting of 3000 cGy of electron-beam radiation to the skin combined with parenteral chemotherapy with cyclophosphamide, doxorubicin, etoposide, and vincristine (n = 52) or sequential topical treatment (n = 51). The prognostic factors were well balanced in the two groups. Combined therapy produced considerable toxicity: 12 patients required hospitalization for fever and transient neutropenia, 5 had congestive heart failure, and 2 were later found to have acute nonlymphocytic leukemia. Patients receiving combined therapy had a significantly higher rate of complete response, documented by biopsy, than patients receiving conservative therapy (38 percent vs. 18 percent; P = 0.032). After a median follow-up of 75 months, however, there was no significant difference between the treatment groups in disease-free or overall survival. We conclude that early aggressive therapy with radiation and chemotherapy does not improve the prognosis for patients with mycosis fungoides as compared with conservative treatment beginning with sequential topical therapies.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1989

In vitro evidence for dose-dependent cytotoxicity as the predominant effect of low dose Ara-C on human leukemic and normal marrow cells.

To determine whether cytosine arabinoside (Ara-C) has a differentiating effect in vitro, marrow cells from nine patients with acute non-lymphocytic leukemia or myelodysplastic syndrome and eight non-leukemic controls were exposed to drug concentrations comparable to those achieved in vivo with low-dose Ara-C therapy. In soft agar cultures, the predominant effect of Ara-C at concentrations between 10(-8) M and 10(-6) M was cytotoxicity with a dose-dependent decrement in Colony Forming Unit of the granulocyte and monocyte lineage (CFUg/m) at 14 days. Growth in liquid cultures containing Giant Cell Tumor(GCT)-conditioned media without Ara-C resulted in a significant increment in the recovery of mature cells at day 10 from the non-leukemic cultures (P = 0.03), while only a minor increase was found in the leukemic cultures (P = 0.09). All liquid cultures exposed to greater than or equal to 10(-9) M Ara-C showed a marked reduction in the immature proliferating cell pool, with a concomitant increase in the percentage of mature non-dividing cells at 10 days. However, the absolute number of differentiated cells recovered remained constant or decreased in all non-leukemic and eight of nine leukemic cultures, compared with cultures without Ara-C. Enhanced recovery of differentiated cells was also never observed in any culture exposed to the relatively non-toxic 10(-9) M Ara-C. These in vitro findings support clinical observations suggesting that cytotoxicity rather than differentiation is the major mechanism involved in the therapeutic effect of low-dose Ara-C in acute leukemia and myelodysplasia.

Bone Marrow↗
PubMed1989

Complement abnormalities in multiple myeloma.

PURPOSE: Patients with multiple myeloma have been shown to have defective opsonization and C3 deposition. Previous studies have suggested that defective C3 deposition may be related to a failure of C3 activation in myeloma serum, the mechanism of which is unknown. We therefore decided to investigate the underlying mechanism responsible for the failure in C3 activation and deposition. PATIENTS AND METHODS: The study consisted of 10 patients from whom a total of 12 serum specimens were obtained. Normal serum was prepared from a pool of serum specimens in four healthy male donors. We evaluated, in vitro, the kinetics of C3 deposition onto zymosan using radiolabeled C3 under various conditions. We also measured the serum levels of a variety of complement components using standard methods. RESULTS: Five of 10 patients' sera demonstrated poor C3 deposition onto zymosan at all time points, whereas an additional two showed poor C3 deposition at early time points but a rebound to normal by 30 minutes. Multiple components of the classical and alternative complement pathways were decreased in many patients, with the most striking abnormalities occurring in those with the poorest C3 deposition. No single complement component abnormality was found to be common to the group. Elevations in Bb fragment concentration strongly suggest in vivo activation as the likely mechanism for depletion of alternative pathway components; the mechanism for classical pathway abnormalities is less clear. There was an inverse correlation between paraprotein concentration and abnormal C3 deposition (p less than 0.0001) and C3 (p less than 0.0005) and C4 (p less than 0.0001) concentrations. However, no consistent evidence of fluid-phase complement consumption was present. CONCLUSION: The defect in C3 activation and deposition in multiple myeloma cannot be explained on the basis of a single complement component abnormality but rather is due to a heterogeneous group of complement abnormalities. Although no correlation between in vitro abnormalities and clinical status was identified in this small group of patients, it is likely that the described complement defects play an important role in defective host defense in multiple myeloma.

Complement Activation↗
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↗