“Continuity of care throughout the lifespan is important for sarcoma patients,” said Leo Mascarenhas, MD, director of the Adult and Pediatric Sarcoma Program and the Division of Pediatric Hematology/Oncology at Cedars-Sinai Cancer. “Our multidisciplinary expertise, which includes pathology, radiation oncology and surgical care, means both adults and children with sarcoma can receive all of their care in one place.”

Mascarenhas is a professor of Pediatrics and Medicine at Cedars-Sinai Health Sciences University and pediatric hematologist-oncologist who has more than 25 years of clinical and research experience. He has led multi-institutional clinical trials for Ewing sarcoma, rhabdomyosarcoma, osteosarcoma and other rare pediatric solid tumors.

Additional Cedars-Sinai Sarcoma Experts

James Hu, MD, associate director of the Sarcoma Program, has more than 30 years of clinical experience in medical oncology. His research focuses on evaluating novel biomarkers and liquid biopsy methods to improve the treatment of bone and soft tissue sarcomas and examining risk factors for young patients facing rare forms of cancer.

Earl Brien, MD, surgical director of the Sarcoma Bone Tumor Program and professor of Orthopaedics, is an orthopedic oncology specialist. His research focuses on surgical strategies for treating complex soft tissue sarcomas, improving surgical techniques for the removal of bone cancers while avoiding amputations, and use of circulating tumor DNA to noninvasively assess treatment response.

Jason Chan, MD, is a board-certified medical oncologist who specializes in the care of people with sarcoma, including desmoid tumors, gastrointestinal stromal tumors (GIST), as well as other soft tissue and bone sarcomas. He studies how cancers adapt and become resistant to treatment, with a focus on the ability of cancer cells to shift into different cell states that may allow them to grow, spread and survive therapy.

Fahima Dossa, MD, PhD, surgical oncologist in the Jim and Eleanor Randall Department of Surgery, primarily treats soft tissue sarcoma, including gastrointestinal stromal tumors (GIST), liposarcoma, leiomyosarcoma and desmoid tumors. She also specializes in treatment of retroperitoneal sarcoma, which develops deep in the fat or muscle of the abdomen, using a specific operative technique to help prevent recurrence.

Behrooz Hakimian, MD, is an assistant professor of Radiation Oncology whose research merges clinical trial exploration with advanced radiation oncology techniques, focusing on patient safety during therapy for complex sarcomas and soft tissue tumors.

Mitchell Kamrava, MD, is a professor of Radiation Oncology whose sarcoma research centers on optimizing preoperative radiation, reducing treatment timelines and predicting post-surgical complications. He has been a co-investigator on pivotal clinical trials evaluating a condensed five-day preoperative radiation regimen for high-risk primary soft tissue sarcomas.

Eugene Kim, MD, is a professor of Surgery and Pediatrics, director of the Division of Pediatric Surgery and vice chair of the Department of Surgery. He is recognized for his expertise in pediatric surgical oncology and he is a key member of the sarcoma team.

Joseph Schwab, MD, director of Spine Oncology in the Department of Orthopaedics, is a specialist in managing sarcomas of the spine—including rare, complex tumors like chondrosarcomas and chordomas—in adults. His research focus includes use of algorithms and machine learning to build tools that optimize clinical decision-making for bone and soft tissue tumors.

Media Contact

To schedule an interview with a Cedars-Sinai sarcoma expert, contact Christina Elston at christina.elston@cshs.org or 626-298-0702.

The study, published in the Journal of Clinical Oncology, evaluated the long-term efficacy of larotrectinib, a drug that specifically targets the TRK fusion protein found in some children under 18 with cancer, more specifically a type of sarcoma. Researchers wanted to understand what happens when young patients stop taking the medicine through a “wait-and-see” protocol.

“Some children were able to stop taking the medicine and still had good results,” said Leo Mascarenhas, MD, MS, corresponding author of the study, director of Pediatric Hematology and Oncology at Cedars-Sinai Guerin Children’s, and medical director of the Sarcoma Program at Cedars-Sinai Cancer. “If their cancer came back, they responded well when they started taking larotrectinib again.”

The study included 91 patients from two clinical trials. Investigators found that out of 47 who stopped taking larotrectinib, 16 had their cancer come back. When these 16 patients started retaking larotrectinib, most responded to the drug and 94% of them benefited.

These findings suggest that doctors can confidently consider stopping larotrectinib treatment in some children with TRK fusion sarcomas, knowing that the same treatment will be effective if the cancer comes back. This study also paves the way for further research into whether stopping targeted treatment could be beneficial for other cancers currently treated with similar medicines.

Other authors include: Steven G. DuBois, MD, MS; Catherine M. Albert, MD; Stefan Bielack, MD; Daniel Orbach, MD; Noah Federman, MD; Birgit Geoerger, MD, PhD; Ramamoorthy Nagasubramanian, MD; Yizhou Zhang, MD; Julia Chisholm, BMBCh, PhD; Soledad Gallego Melcon, MD, PhD; Hiroaki Goto, MD, PhD; Daniel A. Morgenstern, MB, BChir, PhD; Cormac Owens, MD; Alberto S. Pappo, MD; Sébastien Perreault, MD; Johannes H. Schulte, MD; Neerav Shukla, MD; Christian Michel Zwaan, MD, PhD; Natascha Neu, MS; Vadim Bernard-Gauthier, PhD; Esther De La Cuesta, MD, MBA; Cornelis M. van Tilburg, MD, PhD; Theodore W. Laetsch, MD.

Funding: The study was funded by Bayer Healthcare and Loxo Oncology Inc., a wholly owned subsidiary of Eli Lilly and Company.

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