Our physician scientists are actively pursuing sarcoma research projects. Here is a description of some of their work:
Primary Investigators:Laura M. Fayad (MRI) and Rathan Subramanium (PET)
Co-investigator: Elizabeth Montgomery (Pathology) Title: Multiparametric quantitative imaging of neoadjuvant therapy response in malignant soft tissue sarcomas
Soft tissue sarcomas are often treated with a combination of radiation and chemotherapy before surgery is performed to remove the tumor, with the goal of shrinking the tumor, killing the tumor cells and making the surgical removal easier. Ideally, we would like to know how a soft tissue sarcoma responds to radiation or chemotherapy before surgery: If we are able to determine that the chemotherapy is not working adequately to kill the tumor cells, we can change the treatment regimen before the patient goes on to have the tumor removed. Unfortunately, at the present time, we do not have good methods of determining treatment response before surgery; we most accurately determine whether a tumor responded to treatment by the amount of dead tissue that is identified after the tumor is taken out completely, thereby missing an opportunity to change the chemotherapy before surgery.
Through this research project, we will use advanced metabolic imaging techniques with MRI and PET scanning to determine the degree of response to therapy before surgery is performed to remove the sarcoma. We have found, through our preliminary research findings, that a specific metabolic marker picked up by MRI and PET (namely, Choline) can show important metabolic changes in a sarcoma after its cells are successfully treated by chemotherapy. We believe that metabolic imaging with MRI and PET will prove accurate for the prediction of response to therapy and provide valuable information for planning treatment and determining prognosis. These cutting edge imaging techniques have been developed and optimized at Johns Hopkins by members of the Department of Radiology and the Hopkins Sarcoma Program.
Dr. Frassica is a radiation oncologist at Central Maryland Radiation Oncology, a joint collaboration between Johns Hopkins and the University of Maryland Medical Center located in Columbia, Md. Her primary interests are musculoskeletal, breast and colorectal cancers. The center participates in clinical trials under the auspices of the Radiation Therapy Oncology Group, the Eastern Cooperative Oncology Group, the American College of Surgeons Oncology Group, and The Johns Hopkins University.
Dr. Meyer’s research focuses on investigating food pathways that drive sarcomas to grow and divide. Sarcomas use nutrition from common sources such as sugars and proteins to fuel their growth. These common energy sources feed into pathways inside cells that can be blocked with various drugs. He uses both mouse models and cell lines in collaboration with Drs. Loeb and Jonathan Powell to test these drugs and attack these pathways.
One set of drugs targets the mTOR pathway, which drives much of the basic cell nutrition pathways. Research in Dr. Powell’s lab identified a promising combination of mTOR blockade for pancreatic cancer that is now being tested in mouse sarcomas. Given the multiple types of sarcomas, attacking these basic pathways might provide a successful strategy to increase treatment responses in a number of types of them. They are working to bring these combinations from the laboratory to clinical trials.
Dr. Terezakis' research is focused on improving the treatment of children with cancer of several specific types including, rhabdomyosarcoma, other soft tissue sarcomas, Hodgkin lymphoma, and pediatric CNS tumors. Her specific aims are to study how to most effectively utilize radiation therapy in the management of pediatric tumors with regard to the specific issues of indications, timing, sequence with chemotherapy, treatment volume, and dose intensity. Dr. Terezakis also has a specific research interest in assessing the late effects of cranial radiotherapy in brain tumor patients and using novel radiation techniques to treat radioresistant sarcomas.