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Featured researches published by S Singhal.


The New England Journal of Medicine | 1999

Antitumor Activity of Thalidomide in Refractory Multiple Myeloma

S Singhal; Jayesh Mehta; Raman Desikan; Dan Ayers; Paula K. Roberson; Paul Eddlemon; Nikhil C. Munshi; Elias Anaissie; Carla S. Wilson; Madhav V. Dhodapkar; Jerome B. Zeldis; David Siegel; John Crowley; Bart Barlogie

BACKGROUNDnPatients with myeloma who relapse after high-dose chemotherapy have few therapeutic options. Since increased bone marrow vascularity imparts a poor prognosis in myeloma, we evaluated the efficacy of thalidomide, which has antiangiogenic properties, in patients with refractory disease.nnnMETHODSnEighty-four previously treated patients with refractory myeloma (76 with a relapse after high-dose chemotherapy) received oral thalidomide as a single agent for a median of 80 days (range, 2 to 465). The starting dose was 200 mg daily, and the dose was increased by 200 mg every two weeks until it reached 800 mg per day. Response was assessed on the basis of a reduction of the myeloma protein in serum or Bence Jones protein in urine that lasted for at least six weeks.nnnRESULTSnThe serum or urine levels of paraprotein were reduced by at least 90 percent in eight patients (two had a complete remission), at least 75 percent in six patients, at least 50 percent in seven patients, and at least 25 percent in six patients, for a total rate of response of 32 percent. Reductions in the paraprotein levels were apparent within two months in 78 percent of the patients with a response and were associated with decreased numbers of plasma cells in bone marrow and increased hemoglobin levels. The microvascular density of bone marrow did not change significantly in patients with a response. At least one third of the patients had mild or moderate constipation, weakness or fatigue, or somnolence. More severe adverse effects were infrequent (occurring in less than 10 percent of patients), and hematologic effects were rare. As of the most recent follow-up, 36 patients had died (30 with no response and 6 with a response). After 12 months of follow-up, Kaplan-Meier estimates of the mean (+/-SE) rates of event-free survival and overall survival for all patients were 22+/-5 percent and 58+/-5 percent, respectively.nnnCONCLUSIONSnThalidomide is active against advanced myeloma. It can induce marked and durable responses in some patients with multiple myeloma, including those who relapse after high-dose chemotherapy.


The Lancet | 2000

Allogeneic blood and bone-marrow stem-cell transplantation in haematological malignant diseases: a randomised trial

Ray Powles; Jayesh Mehta; Samar Kulkarni; J. Treleaven; B. C. Millar; Jill Marsden; V. Shepherd; April Rowland; Bhawna Sirohi; D. Tait; C Horton; Simon Long; S Singhal

BACKGROUNDnAutologous transplantation with peripheral blood stem cells (PBSC) results in faster haematopoietic-cell repopulation than with bone marrow. We prospectively compared bone marrow and PBSC for allogeneic transplantation.nnnMETHODSnAdult HLA-identical sibling donors provided bone marrow and lenograstim-mobilised PBSC. 39 patients with malignant haematological disorders were infused with either bone marrow (n=19) or PBSC (n=20) after standard conditioning regimens in a double-blind, randomised fashion. The identity of the infused products for all patients remained masked until 1 year after the last patient had received transplantation.nnnFINDINGSnThe PBSC group had significantly faster neutrophil recovery to 0.5x10(9)/L (median 17.5 vs 23 days, p=0.002), and platelet recovery to 20x10(9)/L (median 11 vs 18 days, p<0.0001) and to 50x10(9)/L (median 20.5 vs 27 days, p=0.02) than the bone-marrow group. PBSC patients were discharged from hospital earlier than were bone-marrow patients (median 26 vs 31 days, p=0.01). At 4 weeks after transplantation, absolute lymphocytes (0.48 vs 0.63, p=0.08) and CD25 cells (0.04 vs 0.08, p=0.007) were higher in the PBSC group, and the proportion of patients with absolute lymphopenia (74% vs 33%, p=0.03) and CD4 lymphopenia (59% vs 24%, p=0.05) was significantly higher in the bone-marrow group. There was no significant difference in the occurrence of acute or chronic graft-versus-host disease and overall survival. The probability of relapse was significantly higher in the bone-marrow group than in the PBSC group (p=0.01); all five relapses occurred among bone-marrow recipients.nnnINTERPRETATIONnOur small study indicates that PBSCs are better than bone marrow for allogeneic transplantation from HLA-identical siblings in terms of faster haematopoietic and immune recovery, and have the potential to reduce disease recurrence.


Journal of Clinical Oncology | 1998

Comparable engraftment kinetics following peripheral-blood stem-cell infusion mobilized with granulocyte colony-stimulating factor with or without cyclophosphamide in multiple myeloma.

K. R. Desikan; Bart Barlogie; Sundar Jagannath; David H. Vesole; David Siegel; Athanasios Fassas; Nikhil C. Munshi; S Singhal; Jayesh Mehta; S Tindle; J. Nelson; D Bracy; Sandy Mattox; Guido Tricot

PURPOSEnTo compare, in the setting of tandem autotransplantations for multiple myeloma (MM), two established methods of peripheral-blood stem-cell (PBSC) procurement with chemotherapy or hematopoietic growth factor alone.nnnPATIENTS AND METHODSnBetween June 1994 and July 1995, 44 patients with MM were randomized to PBSC mobilization with either granulocyte colony-stimulating factor (G-CSF) 16 microg/kg (group 1; n = 22) or high-dose cyclophosphamide (HDCTX) 6 g/m2 plus G-CSF 5 microg/kg (group 2; n = 22). All 44 patients received melphalan 200 mg/m2 with their first autograft and 32 patients proceeded to a second transplantation.nnnRESULTSnGroup 2 required a significantly longer time interval for completion of PBSC collection than group 1 (median, 22 v 8 days; P = .0001), greater frequency of hospitalization (100% v 32%; P = .0001), and increased transfusion of platelets (86% v 18%; P = .0001) and packed RBCs (86% v 55%; P = .02). Likewise, the incidence of fever and pneumonia/sepsis were higher in group 2 (P = .02 and P = .04, respectively). Surprisingly, despite greater CD34 cell quantities infused in group 2, median recovery times of granulocytes (both > 500/microL and 2,500/microL) and platelets (both > 50,000/microL and > 100,000/microL) were similar (all P > .7). Posttransplant toxicities were also similar.nnnCONCLUSIONnCompared with HDCTX plus G-CSF, high-dose G-CSF alone is associated with lower morbidity, shorter duration of PBSC mobilization, and comparable hematopoietic recovery after transplantation, which should result in significant cost reduction. Considering the relatively limited antitumor activity of HDCTX (10% with > or = 50% tumor cytoreduction), PBSC mobilization with HDCTX should be limited to selected patients with persistent MM despite induction chemotherapy.


Bone Marrow Transplantation | 1998

Salvage autologous or allogeneic transplantation for multiple myeloma refractory to or relapsing after a first-line autograft?

Jayesh Mehta; Guido Tricot; Sundar Jagannath; Dan Ayers; S Singhal; David Siegel; K. R. Desikan; Nikhil C. Munshi; Athanasios Fassas; Sandy Mattox; David H. Vesole; J Crowley; Bart Barlogie

Forty-two patients allografted for multiple myeloma after not having attained at least a partial remission (nu2009=u200919) or after having experienced disease progression (nu2009=u200923) following one autograft were compared with 42 pair-matched controls who underwent salvage autotransplantation under identical conditions. Autografted controls were matched closely for albumin, C-reactive protein, creatinine, disease sensitivity, duration of standard therapy prior to the first transplant, Ig isotype, karyotype, LDH, and response to the first transplant, but, in comparison to allografted patients, were older, had higher β2-microglobulin, and had a shorter interval between the two transplants. The complete remission rate was 41% after allogeneic and 33% after autologous transplantation (Pu2009=u2009NS). The 3-year probability of event-free survival was comparable for the two groups (25u2009±u20098% after autografting and 20u2009±u20098% after allografting). The 3-year probability of survival was significantly higher after autologous transplantation (54u2009±u20098% vs 29u2009±u20099%; Pu2009=u20090.01). Twenty-one patients in the autograft group were alive 11–59 months (median 32) following the second transplant, while 15 patients in the allograft group were alive at 10–53 months (median 20). The 3-year probability of disease progression was significantly lower after allogeneic transplantation (31u2009±u200910% vs 72u2009±u20099%, Pu2009=u20090.03). The 1-year probability of transplant-related mortality was significantly higher after allografting (43u2009±u20098% vs 10u2009±u20095%; Pu2009=u20090.0001). We conclude that while autografting appears to be superior to allografting for salvage therapy of myeloma persisting or relapsing after one previous autotransplant in terms of overall survival, event-free survival is comparable due to significantly lower disease progression after allografting. Reduction in allograft-related toxicity can potentially improve the results of allogeneic transplantation significantly.


Biomedicine & Pharmacotherapy | 2002

Thalidomide in cancer

S Singhal; Jayesh Mehta

In addition to immunomodulatory and cytokine-modulatory properties, thalidomide has antiangiogenic activity. It has been investigated in a number of cancers including multiple myeloma, myelodysplastic syndromes, gliomas, Kaposi’s sarcoma, renal cell carcinoma, advanced breast cancer, and colon cancer. Its role has been best explored in myeloma, where, at daily doses of 100 to 800mg, it is remarkably active, causing clinically meaningful responses in one-third of extensively pretreated patients and in over half of patients treated early in the course of the disease. It also acts synergistically with corticosteroids and chemotherapy in myeloma. Thalidomide produces improvement of cytopenias characteristic of myelodysplastic syndrome, resulting in the reduction or elimination of transfusion dependence in some patients. Responses have also been seen in one-third of patients with Kaposi’s sarcoma, in a small proportion of patients with renal cell carcinoma and high grade glioma and, in combination with irinotecan, in some patients with colon cancer. Thalidomide is being investigated currently in a number of clinical trials for cancer. Drowsiness, constipation and fatigue are common adverse effects seen in 75% of patients. Symptoms of peripheral neuropathy and skin rash are seen in 30%. A minority of patients experience bradycardia and thrombotic phenomena. Despite the high frequency of adverse effects, those severe enough to necessitate cessation of therapy are seen in only 10 to 15% of patients. A therapeutic trial of thalidomide should be considered in all patients with myeloma who are unresponsive to or relapse after standard therapy. In other malignant diseases, the most appropriate way to use the drug is in the setting of well designed clinical trials. In the absence of access to such studies, thalidomide could be considered singly or in combination with standard therapy in patients with no meaningful therapeutic options.


Bone Marrow Transplantation | 2000

The role of autologous transplantation in patients with multiple myeloma aged 65 years and over

Bhawna Sirohi; R. Powles; J. Treleaven; P Mainwaring; Samar Kulkarni; H Pandha; Niyati Bhagwati; C Horton; S Singhal; Jayesh Mehta

Autologous stem cell transplantation after high-dose melphalan for the treatment with multiple myeloma has resulted in prolonged progression-free survival and overall survival in patients under 65 years. We have examined the role of autologous transplantation in 17 patients with multiple myeloma over 65 years at our centre using a matched pair analysis with younger patients. The median age of this cohort of patients over 65 years was 67 years (65–74) and their outcome and transplant-related morbidity was compared with 17 younger pair mates with a median age of 55 years (31–64). Sixteen patients received high-dose melphalan, and one received busulphan with autologous stem cell rescue. The high-dose therapy was well tolerated in both elderly patients and the matched pairs, with comparable time to recover neutrophils and platelets. Treatment-related mortality also did not differ significantly in both the groups. Median overall survival of the elderly patients was 3.59 years similar to 3.01 years of the pair mates (P = 0.92). Autologous stem cell transplantation after high-dose melphalan conditioning was equally well tolerated in groups of patients above and below 65 years. There was no difference in relapse rate, OS and myelotoxicity in both the groups. These findings suggest that advanced age should not be an exclusion criterion from autologous transplant programmes. Bone Marrow Transplantation (2000) 25, 533–539.


Bone Marrow Transplantation | 2004

Bone marrow transplantation from partially HLA-mismatched family donors for acute leukemia: single-center experience of 201 patients.

Jayesh Mehta; S Singhal; Adrian P. Gee; K. Y. Chiang; Godder K; F van Rhee; S. DeRienzo; W. O'Neal; Lamb L; Henslee-Downey Pj

Summary:Between February 1993 and December 1999, 201 patients (1–59 years old, median 23) with acute leukemia (67% not in remission) underwent ex vivo T-cell-depleted (TCD) bone marrow transplants (BMT) from partially mismatched related donors (PMRD; 92% mismatched for 2–3 HLA A, B, DR antigens). Conditioning comprised total body irradiation, cyclophosphamide, cytarabine, etoposide, anti-thymocyte globulin (ATG), and methylprednisolone. Graft-versus-host disease (GVHD) prophylaxis comprised partial TCD with OKT3 (n=143) or T10B9 (n=58), steroids, ATG, and cyclosporine. The engraftment rate was 98%. The cumulative incidences of grades II–IV acute GVHD and chronic GVHD were 13 and 15%, respectively. The 5-year cumulative incidences of relapse and transplant-related mortality (TRM) were 31 and 51%, respectively. The actuarial 5-year overall survival (OS) and disease-free survival (DFS) probabilities were 19 and 18%, respectively. Patient age >15 years, active disease at transplant, donor age >25 years, and 3-antigen donor mismatch (host-versus-graft) affected the outcome adversely. The actuarial 5-year OS of four groups of patients identified based upon these risk factors was 39, 20, 13, and 0%, respectively (P<0.0001). We conclude that PMRD BMT is a potential treatment option for patients with high-risk acute leukemia who require an alternative donor transplant and fall into a group with a reasonable expected outcome.


Bone Marrow Transplantation | 2001

Candida glabrata and Candida krusei fungemia after high-risk allogeneic marrow transplantation: no adverse effect of low-dose fluconazole prophylaxis on incidence and outcome

A Safdar; F van Rhee; Jp Henslee-Downey; S Singhal; Jayesh Mehta

Candidemia is a serious complication in patients following allogeneic blood, marrow, and organ transplantation. Fourteen patients developed nosocomial fungemia among 204 allogeneic marrow transplants performed during 1997–1999. Incidence of hematogenous candidiasis was 6.8 per 100 allogeneic BMT. All 14 had an indwelling central venous catheter (CVC) and fluconazole (100–200 mg daily) was given prophylactically. In 11 (78.5%) neutropenic patients, duration between agranulocytosis and diagnosis of fungemia was (median, ± s.d.) 10 ± 8 days. Candida glabrata (53.3%) was the most common yeast species, followed by C. krusei (33.3%), and C. parapsilosis (13.3%). Candida albicans was conspicuously absent. Ten patients (71.4%) had primary transplant-related complication (>2 days) including hemolytic uremic syndrome/thrombotic thrombocytopenic purpura (HUS/TTP) (n = 5), severe hemorrhagic cystitis (n = 3), and bacteremia (n = 2). Seven (50.0%) patients expired and in three (21.4%) deaths were attributed to fungemia. The impact of a primary transplant-related complication on short-term survival in this setting was not significant (P = 0.07) (HUS/TTP (P > 0.5); neutropenia (P > 0.5); GVHD (P = 0.35)). Removal of CVC did not alter outcome in our group (P ⩾0.5) although in patients with persistent fungemia (>72u2009h), and those with preceding bacteremia, mortality was significantly higher (P = 0.002). Conventional prognosticators of poor outcome did not adversely effect short-term survival in our transplant recipients with hematogenous candidiasis. The predominance of C. glabrata and C. krusei breakthrough infections was similar to what is seen with high-dose fluconazole (400 mg) prophylaxis, and no adverse effects of low-dose fluconazole in terms of increased incidence of non-susceptible Candida species was seen. Bone Marrow Transplantation (2001) 28, 873–878.


Bone Marrow Transplantation | 2002

Response to induction chemotherapy is not essential to obtain survival benefit from high-dose melphalan and autotransplantation in myeloma.

S Singhal; R. Powles; Bhawna Sirohi; J. Treleaven; Samar Kulkarni; Jayesh Mehta

Two hundred and twenty-two myeloma patients autografted after 200 mg/m2melphalan were studied to examine the relationship between response to induction chemotherapy and outcome. Induction comprised cyclophosphamide, vincristine, doxorubicin and methylprednisolone (C-VAMP) every 3 weeks for one cycle beyond maximum response. 81% responded to C-VAMP (chemosensitive) with 40 complete (CR) and 139 partial (PR) remissions, and 43 did not respond (NR; <50% reduction in paraprotein; primary refractory). Overall, 130 patients (59%) attained or remained in CR post-transplant; including 40% of NR, 53% of PR, and 97% of CR after C-VAMP (P < 0.0001). Amongst these 130 patients, the 5-year OS was independent of response to C-VAMP (NR 79%, PR 74%, CR 60%; P = 0.69). Similarly, among the 69 patients in PR post-transplant, the 5-year OS was independent of response to C-VAMP. In Cox analysis, lack of response to C-VAMP did not affect outcome significantly. These data show that lack of response to induction therapy does not automatically predict poor long-term outcome in myeloma, since a substantial proportion of these patients attain CR after autograft and enjoy extended survival. Myeloma patients should not be disqualified from an autograft based upon lack of response to induction chemotherapy.


British Journal of Haematology | 1999

High-dose therapy with autologous haemopoietic stem cell support for Waldenström's macroglobulinaemia.

Raman Desikan; Madhav V. Dhodapkar; David Siegel; Athanasios Fassas; J. Singh; S Singhal; Jayesh Mehta; David H. Vesole; Guido Tricot; Sundar Jagannath; Elias Anaissie; Bart Barlogie; Nikhil C. Munshi

Standard doses of alkylating agents or purine analogues effect response rates of up to 50% in Waldenströms macroglobulinaemia (WM); however, complete responses are infrequent and there are no cures. We have evaluated the feasibility, safety and efficacy of high‐dose chemotherapy with peripheral blood stem cell support in six patients aged 45–69 years (median 51.5) with WM; four patients relapsed after prior therapy inclusive of purine analogues and two patients proceeded with transplant after minimal therapy. Four patients mobilized adequate numbers of stem cells; however, two patients with more extensive fludarabine therapy failed to mobilize and required a second attempt at stem cell collection. Five patients were treated with melphalan 200u2003mg/m2, including one patient who received tandem transplants and one patient who received melphalan 140u2003mg/m2 with added total body irradiation (TBI). There was no treatment‐related mortality and non‐haematological toxicities were manageable. Engraftment was prompt except in one patient with extensive prior use of fludarabine. All the six patients achieved at least partial response (PR), including one who achieved complete response (CR). Five patients are alive and four are event‐free at 52+, 15+, 12+ and 2+ months post transplant. This pilot study suggests safety and efficacy of high‐dose therapy in WM and suggests that the peripheral blood stem cells should preferably be procured prior to extensive use of purine analogues.

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Jayesh Mehta

Northwestern University

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J. Treleaven

The Royal Marsden NHS Foundation Trust

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R. Powles

The Royal Marsden NHS Foundation Trust

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C Horton

The Royal Marsden NHS Foundation Trust

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Samar Kulkarni

The Royal Marsden NHS Foundation Trust

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Radovan Saso

The Royal Marsden NHS Foundation Trust

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Bhawna Sirohi

The Royal Marsden NHS Foundation Trust

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Ray Powles

The Royal Marsden NHS Foundation Trust

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Bart Barlogie

University of Arkansas for Medical Sciences

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