Cancers known as sarcomas develop in the connective tissues, such as muscle, fat, and bone, that hold the body together. The type of sarcoma diagnosed in Toronto Mayor Rob Ford, liposarcoma, originates in fat cells that have been driven by random DNA errors into malignant growth, forming tumors.
George Demetri, MD, Director of Dana-Farber’s Center for Sarcoma and Bone Oncology, notes that while sarcomas are not a common form of cancer, they are not rare: about 10,000 sarcoma cases are diagnosed in the United States each year.
Liposarcomas, which most often affect middle-age and older adults, develop as large, bulky masses inside the abdomen, causing no symptoms until they cause pain by pressing on vital structures. There are no known risk factors for this type of cancer, Demetri says.
Liposarcomas are classified as well-differentiated, dedifferentiated, mixoid, and pleomorphic. The latter are the most rare and most aggressive type, and Ford reportedly has a pleomorphic tumor.
They are diagnosed by examination of biopsied tissue, and Demetri says determining which type of liposarcoma a patient has is extremely important and “very challenging,” requiring special expertise and DNA testing.
“There is a lot of hope for patients with liposarcoma,” says Demetri. New drugs are being developed that home in on DNA abnormalities, or targets, within the tumor cells. Often these drugs inhibit overactive proteins or enzymes in the cancer that cause it to grow uncontrollably. Some drugs of this type are now in clinical trials.