LeoMascarenhasMD

Pediatric Hematology & Oncology • Los Angeles, CA

Professor, Cedar Sinai Medical Center Director, Pediatric Hematology Oncology Director, Sarcoma Oncology

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Office
8700 Beverly Boulevard
NT Suite 4221
Los Angeles, CA 90048
Phone+1 310-423-4423

Summary

I am a board-certified pediatrician and pediatric hematologist-oncologist academically focused on developmental therapeutics for pediatric and adolescent solid tumors with a particular expertise in bone and soft tissue sarcomas and developmental therapeutics for solid tumors including Wilms tumor and hepatoblastoma. My research interest is to investigate molecular targeted therapy and immunotherapy alone or in combination with chemotherapy in sarcomas and pediatric solid tumors. I have been actively involved in clinical research for more than 25 years with experience in designing and conducting Phase I, Phase II and Phase III clinical trials. I presently serve as the Chair of the Voting Body of the Children’s Oncology Group (COG), the institutional Principal Investigator (PI) for COG at Cedar-Sinai and was the institutional COG PI for 16 years until October 2023 and the PI for the Pediatric Early Phase Clinical Trials Network (PEPCTN) at Children's Hospital Los Angeles until August 2019. I have been the principal investigator on three investigator-initiated institutional Phase I clinical trials, serve/d as the principal investigator, co-principal investigator, co-investigator on several COG Phase II/III clinical trials and lead investigator on four pharma sponsored trials. I also serve as the local principal investigator on Sarcoma Alliance for Research through Collaboration (SARC) clinical trials and other multi- institutional clinical trials that are either consortia-based investigator-initiated or pharmaceutical industry supported. I am committed to improving outcomes for children and adolescents with cancer through clinical research. I am also a committed mentor and educator to peers and colleagues. I have multiple publications in which I have collaborated on with my mentees. I provide education to others to improve outcomes for children with cancer as well as enhance the knowledge and skills of the medical scientific community.

Education & Training

Children's Hospital Los AngelesFellowship, Pediatric Hematology/Oncology, 1995 - 1998
Westchester Medical CenterResidency, Pediatrics, 1992 - 1995
St. John's Medical CollegeClass of 1991

Certifications & Licensure

CA State Medical License 1995 - 2026
American Board of Pediatrics Pediatrics
American Board of Pediatrics Pediatric Hematology-Oncology

Awards, Honors, & Recognition

Super Doctor SuperDoctors.com

Clinical Trials

Combination Chemotherapy With or Without Peripheral Stem Cell Transplantation, Radiation Therapy, and/or Surgery in Treating Patients With Ewing's Sarcoma Start of enrollment: 2001 Feb 01
Unknown status
Phase 3
Isotretinoin With or Without Dinutuximab, Aldesleukin, and Sargramostim Following Stem Cell Transplant in Treating Patients With Neuroblastoma Start of enrollment: 2001 Oct 18
Active, not recruiting
Phase 3
Vincristine, Dactinomycin, and Cyclophosphamide With or Without Radiation Therapy in Treating Patients With Newly Diagnosed Low-Risk Rhabdomyosarcoma Start of enrollment: 2004 Sep 04
Completed
Phase 3
Genetic Analysis in Identifying Late-Occurring Complications in Childhood Cancer Survivors Start of enrollment: 2004 Mar 25
Recruiting
Comparison of Radiation Therapy Regimens in Combination With Chemotherapy in Treating Young Patients With Newly Diagnosed Standard-Risk Medulloblastoma Start of enrollment: 2004 Apr 01
Active, not recruiting
Phase 3
Combination Chemotherapy, PEG-Interferon Alfa-2b, and Surgery in Treating Patients With Osteosarcoma Start of enrollment: 2005 Nov 14
Completed
Phase 3
Study to Assess Compliance With Long-Term Mercaptopurine Treatment in Young Patients With Acute Lymphoblastic Leukemia in Remission Start of enrollment: 2005 May 30
Completed
Radiation Therapy, Amifostine, and Chemotherapy in Treating Young Patients With Newly Diagnosed Nasopharyngeal Cancer Start of enrollment: 2006 Feb 20
Completed
Phase 3
Cisplatin-Based Chemotherapy and/or Surgery in Treating Young Patients With Adrenocortical Tumor Start of enrollment: 2007 May 03
Completed
Phase 3
Etanercept in Treating Young Patients With Idiopathic Pneumonia Syndrome After Undergoing a Donor Stem Cell Transplant Start of enrollment: 2006 Apr 01
Completed
Phase 2
Combination Chemotherapy With or Without Topotecan in Treating Patients With Newly Diagnosed Localized Ewing's Sarcoma Start of enrollment: 2005 Dec 01
Withdrawn
Phase 3
Combination Chemotherapy, Radiation Therapy, and/or Surgery in Treating Patients With High-Risk Kidney Tumors Start of enrollment: 2006 Jun 01
Completed
Phase 2
Combination Chemotherapy Followed By Peripheral Stem Cell Transplant in Treating Young Patients With Newly Diagnosed Supratentorial Primitive Neuroectodermal Tumors or High-Risk Medulloblastoma Start of enrollment: 2007 Aug 06
Active, not recruiting
Phase 3
Vincristine, Dactinomycin, and Doxorubicin With or Without Radiation Therapy or Observation Only in Treating Younger Patients Who Are Undergoing Surgery for Newly Diagnosed Stage I, Stage II, or Stage III Wilms' Tumor Start of enrollment: 2006 Nov 06
Active, not recruiting
Phase 3
Combination Chemotherapy and Radiation Therapy in Treating Patients With Newly Diagnosed Rhabdomyosarcoma Start of enrollment: 2006 Dec 26
Completed
Phase 3
Combination Chemotherapy in Treating Young Patients With Down Syndrome and Acute Myeloid Leukemia or Myelodysplastic Syndromes Start of enrollment: 2007 Mar 01
Completed
Phase 3
Combination Chemotherapy With or Without Radiation Therapy in Treating Young Patients With Newly Diagnosed Stage III or Stage IV Wilms' Tumor Start of enrollment: 2007 Feb 26
Active, not recruiting
Phase 3
Low-Dose or High-Dose Vincristine and Combination Chemotherapy in Treating Young Patients With Relapsed B-Cell Acute Lymphoblastic Leukemia Start of enrollment: 2007 Mar 01
Completed
Phase 3
Chemotherapy and Radiation Therapy in Treating Young Patients With Newly Diagnosed, Previously Untreated, High-Risk Medulloblastoma/PNET Start of enrollment: 2007 Mar 26
Active, not recruiting
Phase 3
Combination Chemotherapy in Treating Young Patients With Newly Diagnosed T-Cell Acute Lymphoblastic Leukemia or T-cell Lymphoblastic Lymphoma Start of enrollment: 2007 Jan 22
Active, not recruiting
Phase 3
Brain Function in Young Patients Receiving Methotrexate for Acute Lymphoblastic Leukemia Start of enrollment: 2007 Jan 01
Completed
Assessing Ear Damage in Young Cancer Patients Treated With Cisplatin Start of enrollment: 2007 May 01
Completed
Combination Chemotherapy, Autologous Stem Cell Transplant, and/or Radiation Therapy in Treating Young Patients With Extraocular Retinoblastoma Start of enrollment: 2008 Feb 04
Active, not recruiting
Phase 3
Combination Chemotherapy, Radiation Therapy, and an Autologous Peripheral Blood Stem Cell Transplant in Treating Young Patients With Atypical Teratoid/Rhabdoid Tumor of the Central Nervous System Start of enrollment: 2009 Feb 10
Completed
Phase 3
Genetic Mutations and Environmental Exposure in Young Patients With Retinoblastoma and in Their Parents and Young Healthy Unrelated Volunteers Start of enrollment: 2008 Jun 02
Completed
Sodium Thiosulfate in Preventing Hearing Loss in Young Patients Receiving Cisplatin for Newly Diagnosed Germ Cell Tumor, Hepatoblastoma, Medulloblastoma, Neuroblastoma, Osteosarcoma, or Other Malignancy Start of enrollment: 2008 Jun 23
Completed
Phase 3
Long-Term Follow-Up of Patients Who Have Participated in Children's Oncology Group Studies Start of enrollment: 2008 Jul 17
Recruiting
Neuropsychological and Behavioral Testing in Younger Patients With Cancer Start of enrollment: 2009 Feb 27
Recruiting
Cixutumumab in Treating Patients With Relapsed or Refractory Solid Tumors Start of enrollment: 2009 Jan 01
Completed
Phase 2
Combination Chemotherapy in Treating Young Patients With Newly Diagnosed Acute Promyelocytic Leukemia Start of enrollment: 2009 Mar 09
Completed
Phase 3
Collecting and Storing Samples of Bone Marrow and Blood From Patients With Relapsed Acute Lymphoblastic Leukemia or Non-Hodgkin Lymphoma Start of enrollment: 2006 Sep 25
Completed
Collecting and Storing Malignant, Borderline Malignant Neoplasms, and Related Samples From Young Patients With Cancer Start of enrollment: 2003 Oct 13
Completed
Study of Kidney Tumors in Younger Patients Start of enrollment: 2006 Feb 27
Recruiting
Collecting and Storing Samples of Blood and Tumor Tissue From Patients With Osteosarcoma Start of enrollment: 2008 Feb 04
Completed
Collecting and Storing Biological Samples From Patients With Ewing Sarcoma Start of enrollment: 2008 Feb 04
Completed
Collecting and Storing Biological Samples From Young Patients With Hodgkin?s Lymphoma Start of enrollment: 2006 Oct 23
Completed
Biomarkers in Tumor Tissue Samples From Patients With Newly Diagnosed Neuroblastoma or Ganglioneuroblastoma Start of enrollment: 2000 Nov 06
Recruiting
Collecting and Storing Tissue, Blood, and Bone Marrow Samples From Patients With Rhabdomyosarcoma or Other Soft Tissue Sarcoma Start of enrollment: 1999 Mar 15
Completed
Collecting and Storing Blood and Brain Tumor Tissue Samples From Children With Brain Tumors Start of enrollment: 2004 Feb 16
Completed
Combination Chemotherapy and Surgery in Treating Young Patients With Wilms Tumor Start of enrollment: 2009 Jul 13
Active, not recruiting
Phase 3
Study of Blood Samples From Newborns With Down Syndrome Start of enrollment: 2009 Feb 23
Completed
Risk-Based Therapy in Treating Younger Patients With Newly Diagnosed Liver Cancer Start of enrollment: 2009 Sep 14
Active, not recruiting
Phase 3
A Study of Vincristine, Escalating Doses of Irinotecan, Temozolomide and Bevacizumab (Vit-b) in Pediatric and Adolescent Patients With Recurrent or Refractory Solid Tumors of Non-hematopoietic Origin Start of enrollment: 2009 Sep 01
Completed
Phase 1
Collecting and Storing Tissue Samples From Patients With Rare or Cutaneous Non-Hodgkin Lymphoma Start of enrollment: 2005 May 30
Completed
Monoclonal Antibody Ch14.18, Sargramostim, Aldesleukin, and Isotretinoin After Autologous Stem Cell Transplant in Treating Patients With Neuroblastoma Start of enrollment: 2009 Dec 21
Completed
Phase 3
Temozolomide, Cixutumumab, and Combination Chemotherapy in Treating Patients With Metastatic Rhabdomyosarcoma Start of enrollment: 2010 Jan 01
Completed
Phase 2
Maintenance Chemotherapy or Observation Following Induction Chemotherapy and Radiation Therapy in Treating Patients With Newly Diagnosed Ependymoma Start of enrollment: 2010 May 07
Active, not recruiting
Phase 3
Risk-Based Classification System of Patients With Newly Diagnosed Acute Lymphoblastic Leukemia Start of enrollment: 2010 Aug 09
Completed
Alisertib in Treating Young Patients With Recurrent or Refractory Solid Tumors or Leukemia Start of enrollment: 2011 Feb 01
Completed
Phase 2
Induction Therapy Including 131 I-MIBG and Chemotherapy in Treating Patients With Newly Diagnosed High-Risk Neuroblastoma Undergoing Stem Cell Transplant, Radiation Therapy, and Maintenance Therapy With Isotretinoin Start of enrollment: 2010 Oct 04
Active, not recruiting
Phase 1
Risk-Adapted Chemotherapy in Treating Younger Patients With Newly Diagnosed Standard-Risk Acute Lymphoblastic Leukemia or Localized B-Lineage Lymphoblastic Lymphoma Start of enrollment: 2010 Aug 09
Active, not recruiting
Phase 3
Temozolomide and Irinotecan Hydrochloride With or Without Bevacizumab in Treating Young Patients With Recurrent or Refractory Medulloblastoma or CNS Primitive Neuroectodermal Tumors Start of enrollment: 2010 Nov 22
Completed
Phase 2
Vinorelbine Tartrate and Cyclophosphamide in Combination With Bevacizumab or Temsirolimus in Treating Patients With Recurrent or Refractory Rhabdomyosarcoma Start of enrollment: 2010 Oct 01
Completed
Phase 2
Combination Chemotherapy in Treating Patients With Non-Metastatic Extracranial Ewing Sarcoma Start of enrollment: 2010 Nov 22
Active, not recruiting
Phase 3
Caspofungin Versus Fluconazole in Preventing Invasive Fungal Infections (IFI) in Patients Undergoing Chemotherapy for Acute Myeloid Leukemia Start of enrollment: 2011 Apr 04
Completed
Phase 3
Biological Therapy, Sargramostim, and Isotretinoin in Treating Patients With Relapsed or Refractory Neuroblastoma Start of enrollment: 2011 Sep 01
Completed
Phase 2
Levofloxacin in Preventing Infection in Young Patients With Acute Leukemia Receiving Chemotherapy or Undergoing Stem Cell Transplantation Start of enrollment: 2011 Sep 01
Completed
Phase 3
Bortezomib and Sorafenib Tosylate in Treating Patients With Newly Diagnosed Acute Myeloid Leukemia Start of enrollment: 2011 Jun 20
Active, not recruiting
Phase 3
A Phase III Randomized Trial for Newly Diagnosed High Risk B-precursor Acute Lymphoblastic Leukemia (ALL) Testing Clofarabine (IND# 73789, NSC# 606869) in the Very High Risk Stratum Start of enrollment: 2012 Feb 01
Sunitinib Malate in Treating Younger Patients With Recurrent, Refractory, or Progressive Malignant Glioma or Ependymoma Start of enrollment: 2012 Jan 01
Completed
Phase 2
Assessing Compliance With Mercaptopurine Treatment in Younger Patients With Acute Lymphoblastic Leukemia in First Remission Start of enrollment: 2012 Feb 21
Active, not recruiting
Phase 3
Intergroup Trial for Children or Adolescents With B-Cell NHL or B-AL: Evaluation of Rituximab Efficacy and Safety in High Risk Patients Start of enrollment: 2012 Jun 01
Chemotherapy Followed by Radiation Therapy in Treating Younger Patients With Newly Diagnosed Localized Central Nervous System Germ Cell Tumors Start of enrollment: 2012 Jun 27
Active, not recruiting
Phase 2
Phase 2 Study of Inhaled Lipid Cisplatin in Pulmonary Recurrent Osteosarcoma Start of enrollment: 2012 Aug 01
Completed
Phase 2
Sorafenib and Topotecan in Refractory/Recurrent Pediatric Malignancies Start of enrollment: 2013 Jan 01
Completed
Phase 1
Irinotecan Hydrochloride and Temozolomide With Temsirolimus or Dinutuximab in Treating Younger Patients With Refractory or Relapsed Neuroblastoma Start of enrollment: 2013 Feb 12
Completed
Phase 2
Brentuximab Vedotin and Gemcitabine Hydrochloride in Treating Younger Patients With Relapsed or Refractory Hodgkin Lymphoma Start of enrollment: 2013 Jan 31
Completed
Phase 1, Phase 2
Chlorhexidine Gluconate Cleansing in Preventing Central Line Associated Bloodstream Infection and Acquisition of Multi-drug Resistant Organisms in Younger Patients With Cancer or Undergoing Donor Stem Cell Transplant Start of enrollment: 2013 Nov 04
Completed
Phase 3
Eribulin Mesylate in Treating Patients With Recurrent or Refractory Osteosarcoma Start of enrollment: 2014 Aug 01
Completed
Phase 2
Combination Chemotherapy With or Without Bortezomib in Treating Younger Patients With Newly Diagnosed T-Cell Acute Lymphoblastic Leukemia or Stage II-IV T-Cell Lymphoblastic Lymphoma Start of enrollment: 2014 Oct 04
Active, not recruiting
Phase 3
Radiation Therapy With or Without Combination Chemotherapy or Pazopanib Before Surgery in Treating Patients With Newly Diagnosed Non-rhabdomyosarcoma Soft Tissue Sarcomas That Can Be Removed by Surgery Start of enrollment: 2014 Jul 11
Active, not recruiting
Phase 2, Phase 3
Risk-Based Therapy in Treating Younger Patients With Newly Diagnosed Liver Cancer Start of enrollment: 2009 Sep 01
A Study to Test the Safety and Efficacy of the Drug Larotrectinib for the Treatment of Tumors With NTRK-fusion in Children Start of enrollment: 2015 Dec 16
Active, not recruiting
Phase 1, Phase 2
A Study of Olaratumab (LY3012207) in Participants With Advanced Soft Tissue Sarcoma Start of enrollment: 2016 Mar 01
Completed
Phase 1, Phase 2
Durvalumab in Pediatric and Adolescent Patients Start of enrollment: 2016 Jul 01
Completed
Phase 1
Nab-Paclitaxel and Gemcitabine for Recurrent/Refractory Sarcoma Start of enrollment: 2016 Oct 25
Active, not recruiting
Phase 2
Irinotecan Hydrochloride, Temozolomide, and Dinutuximab With or Without Eflornithine in Treating Patients With Relapsed or Refractory Neuroblastoma Start of enrollment: 2019 Jul 08
Active, not recruiting
Phase 2
A Study to Investigate Blinatumomab in Combination With Chemotherapy in Patients With Newly Diagnosed B-Lymphoblastic Leukemia Start of enrollment: 2019 Jul 03
Recruiting
Phase 3
A Study of Repotrectinib in Pediatric and Young Adult Subjects Harboring ALK, ROS1, OR NTRK1-3 Alterations Start of enrollment: 2020 Mar 12
Recruiting
Phase 1, Phase 2
Lurbinectedin in FET-Fused Tumors Start of enrollment: 2023 Jul 27
Recruiting
Phase 1, Phase 2
Roles: Contact
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Publications & Presentations

PubMed

Phase II Trial of Gemcitabine and Nab-Paclitaxel for Recurrent Osteosarcoma with Serial Monitoring Using Liquid Biopsy: A Report from the National Pediatric Cancer Fou...
Aditi Dhir, Masanori Hayashi, Avery Bodlak, Javier Oesterheld, David M Loeb
Clinical Cancer Research. 2024-12-02
2 citations
Embryonal sarcoma of the liver in pediatric and young adult patients: A report from Children's Oncology Group study ARST0332.
Sheri L Spunt, Wei Xue, Zhengya Gao, Andrea Hayes Dixon, Lynn Million
Cancer. 2024-08-01
2 citations
Adolescents and young adults with rhabdomyosarcoma: A report from the Soft Tissue Sarcoma Committee of the Children's Oncology Group.
Douglas J Harrison, Amira Qumseya, Wei Xue, Michael Arnold, Timothy B Lautz
Pediatric Blood & Cancer. 2024-04-01

Lectures

ASPHO 2013 Review Course
American Society of Pediatric Hematology/Oncology( ASPHO), Dallas, Texas - 2/7/2013

Press Mentions

Children’s Hospital Los Angeles Develops Liquid Biopsy Test for Pediatric Solid TumorsMarch 2nd, 2023
Children’s Hospital Los Angeles Breakthrough Study with RhabdomyosarcomaSeptember 18th, 2019
Breaking the 'Stalemate' in the Most Common Soft Tissue Sarcoma in ChildrenSeptember 12th, 2019
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