Leo Mascarenhas, MD, MS

Deputy Director, Cancer and Blood Disease Institute
Section Head, Oncology
Attending Physician; Hematology, Oncology and Blood and Marrow Transplantation
Investigator, Hematology-Oncology
Associate Professor of Pediatrics, Keck School of Medicine of USC

Leo Mascarenhas, MD is the Deputy Director of the Cancer and Blood Disease Institute and the Section Head of Oncology within the Division of Hematology, Oncology and Blood and Marrow Transplantation at Children’s Hospital Los Angeles (CHLA).  He is also the Director of the Solid Tumor Program and the Director of the Clinical Trials Program within the Institute, and the Principal Investigator of the National Cancer Institute (NCI) funded Children’s Oncology Group (COG) at CHLA.

Dr. Mascarenhas is an Associate Professor of Pediatrics in the Keck School of Medicine of the University of Southern California. He joined CHLA in 1995 for his fellowship and has been on the faculty since 1998. Dr. Mascarenhas is an internationally recognized expert in pediatric bone and soft tissue tumors and has consistently been listed in Best Doctors in America®, America’s Top Pediatricians®, Southern California Super Doctors®, and Top Doctors Pasadena®.

Dr. Mascarenhas serves on the Board of Directors of the American Society of Pediatric Hematology/Oncology and Vice Chair of the Voting Body and Member of the Bone Sarcoma and Soft Tissue Sarcoma Committee of the Children’s Oncology Group. In addition, he serves on the Board of Directors and is the Chair of the Scientific Advisory Board of the Pablove Foundation.

Clinical Interests

Bone Sarcomas (Osteosarcoma, Ewing Sarcoma, Chondrosarcoma), Soft Tissue Sarcomas (Rhabdomyosarcoma, Ewing Sarcoma, Synovial Sarcoma, Malignant Peripheral Nerve Sheath Tumors-MPNST, Other Soft Tissue Sarcomas), Wilms Tumor, Liver Tumors, Germ Cell Tumors, Melanoma, Pleuropulmonary Blastoma, Desmoplastic Small Round Cell Tumor, Rare Pediatric Cancers, and Vascular Anomalies including Lymphangiomatosis, Gorham’s Disease, and Hemangioendothelioma


Medical School

St. John’s Medical College, Bangalore, India


St. John’s Medical College, General Rotating Internship


New York Medical College, General Pediatrics


Children’s Hospital Los Angeles, Pediatric Hematology/Oncology, and Blood and Marrow Transplantation



American Board of Pediatrics (General Pediatrics); American Board of Pediatric Hematology/Oncology


American Academy of Pediatrics; American Society of Pediatric Hematology/Oncology; American Society of Clinical Oncology; Connective Tissue Oncology Society; Society of Pediatric Research; Children’s Oncology Group.

Medical Awards

Bristol Myers Squibb Award for Superior Academic Achievement, New York Medical College, 1995; Philip E. Rothman Memorial Award for Outstanding Teaching, 2006; Walter Laug Distinguished Teaching Award for Inspirational Teaching and Guidance, 2009




  1. De Novo Congenital Melanoma: Analysis of 2 Cases With Array Comparative Genomic Hybridization.Su A, Low L, Li X, Zhou S, Mascarenhas L, Barnhill RL. Am J Dermatopathol. 2014 Jul 21. [Epub ahead of print] PMID: 25051103 [PubMed - as supplied by publisher]

  2. Screening for cardiac dysfunction in anthracycline-exposed childhood cancer survivors. Armenian SH, Gelehrter SK, Vase T, Venkatramani R, Landier W, Wilson KD, Herrera C, Reichman L, Menteer JD, Mascarenhas L, Freyer DR, Venkataraman K, Bhatia S. Clin Cancer Res. 2014 Jun 19. pii: clincanres.3490.2014. [Epub ahead of print] PMID: 24947931 [PubMed - as supplied by publisher]

  3. Pulmonary function abnormalities in childhood cancer survivors treated with bleomycin.De A, Guryev I, LaRiviere A, Kato R, Wee CP, Mascarenhas L, Keens TG, Venkatramani R. Pediatr Blood Cancer. 2014 Sep;61(9):1679-84. doi: 10.1002/pbc.25098. Epub 2014 May 2. PMID: 24789770 [PubMed - in process]

  4. High dose alkylator therapy for extracranial malignant rhabdoid tumors in children.Venkatramani R, Shoureshi P, Malvar J, Zhou S, Mascarenhas L. Pediatr Blood Cancer. 2014 Aug;61(8):1357-61. doi: 10.1002/pbc.25093. Epub 2014 Apr 30. PMID: 24789740 [PubMed - indexed for MEDLINE]

  5. Carnitine and cardiac dysfunction in childhood cancer survivors treated with anthracyclines. Armenian SH, Gelehrter SK, Vase T, Venkatramani R, Landier W, Wilson KD, Herrera C, Reichman L, Menteer JD, Mascarenhas L, Freyer DR, Venkataraman K, Bhatia S. Cancer Epidemiol Biomarkers Prev. 2014 Jun;23(6):1109-14. doi: 10.1158/1055-9965.EPI-13-1384. Epub 2014 Apr 9. PMID: 24718281 [PubMed - in process]


Research Summary

Early phase clinical trials for sarcomas and pediatric solid tumors, Phase III trials for sarcomas, Molecular targeted therapy, and Immunotherapy

Research Topics

  • Acute Lymphoblastic Leukemia

  • Bone and Soft Tissue Tumors

  • Hepatoblastoma

  • Ewing Sarcoma

  • Osteosarcoma

Research Overview

Leo Mascarenhas, MD is director of the Clinical Trials Office in the Children’s Center for Cancer and Blood Diseases and Principal Investigator for the National Cancer Institute funded Children’s Oncology Group grant at Children’s Hospital Los Angeles. He is an associate professor of Clinical Pediatrics at the Keck School of Medicine of the University of Southern California.

Childhood cancer is the leading cause of disease-related death in pediatrics in the United States. Dr. Mascarenhas and his team's research focuses on developmental therapeutics for patients with bone and soft tissue sarcomas. Despite the remarkable progress made in the treatment of childhood cancer in the last four decades, improved therapies are still needed for our patients with a poor prognosis and less toxic therapies for those destined to survive. This can be accomplished only through basic, translational and clinical research.

Childhood Cancer Research 

Cancer can be caused by changes in our DNA. Scientists have come to understand that cancer may also result from epigenetic changes that are caused by an accumulation of chemical signals that can switch a gene on or off. Epigenetic alterations have been shown to be associated with the development of cancer, drug resistance and disease relapse. Research indicates that these alterations in cancer cells and drug resistance can be overcome using certain medications. The next step is to test these medications in patients.

Key Findings

  • Discovered first epigenetic drug combination used in pediatric AML patients. If effective, this may provide a new strategy to overcome resistance in children with other types of cancer.
  • Created Therapeutic Advances in Childhood Leukemia and Lymphoma (TACL), that is focused on translational research in early phase clinical trials for childhood cancer. The operation center for TACL is located at Children’s Hospital Los Angeles. 


  • National Institute of Health (NIH)