A promising new study was completed last summer regarding the effectiveness of using hyperthermia in conjunction with chemotherapy and liposomes to reduce the size of cancer tumors that would otherwise be considered inoperable. In 2002, 21 patients of Dr. Kimberly Blackwell attended the Duke Comprehensive Cancer Center for the phase I trial. These women suffered from breast cancers termed “inflammatory” and “locally advanced” where 60 to 70 percent generally do not survive for longer than five years.
The goal of the study was to deliver enough chemotherapy to remove the tumor, reduce the size of the tumor or halt the tumor from growing. It has been an accepted fact that virtually all cancer cells can be destroyed if enough chemotherapy is delivered to them. Unfortunately, often times in later stage cancer tumors it is impossible to deliver this high amount of chemotherapy in fear of poisoning the patient or causing significantly negative side effects.
This study is the first study of its kind in the US which alters the traditional chemotherapy delivery by encasing the chemotherapy in liposomes (tiny fat bubbles) and delivering them via hyperthermia (heat therapy). Every three weeks for four cycles women receive chemotherapy in liposomes then lie on a table for one hour while their breasts sit in a pool of water heated by radio frequencies. The heat draws the liposome out of the bloodstream and triggers the liposome to melt within 20 seconds, thus delivering the chemotherapy directly to the site of the tumor.
Because only the breasts are heated and the rest of the body remains at normal temperature, the chemotherapy medications are not directly delivered to other body parts causing harmful toxicity. Dr. Blackwell explains, “Encapsulating the chemotherapy inside of liposomes enables us to deliver 30 times more chemotherapy than we normally could to the tumor site, without poisoning the rest of the body. Heat also boosts the drugs’ potency by interfering with mechanisms that control a cancer cell’s ability to replicate.” Furthermore, heat increases the uptake of chemotherapy drugs into the cancer cells, increases the oxygen levels inside the tumor which is critical to the proper functioning of the chemotherapy drugs and inhibits enzymes that normally repair DNA damage inflicted by the chemotherapy drugs.
The results of the study have been dramatically successful. Dr. Blackwell reports that, “In several cases, the treatment has remarkably destroyed all visible signs of the tumor. In others, the treatment has saved women’s breasts from surgical removal. In every case, it has halted the tumor from growing.” Dr. Blackwell explains that these numbers are significant because most of the 21 patients were told that their tumors were inoperable in that the tumors were either so large or invasive that they had already spread to the skin, chest wall or surrounding muscles. Although subsequent trials still need to be conducted, chemotherapy – liposome hyperthermia shows promising results in the treatment of later stage breast cancers.