Sept. 23, 2009 (Berlin) -- Tumors in soft tissues such as muscle, fat, and nerves around the joints are much less likely to come back if they are heated at the time patients receive chemotherapy, a study shows.
There's also a suggestion that patients who receive targeted heat therapy may live longer, says the study's leader, Rolf Issels, MD, a professor of medical oncology at Klinikum Grosshadern Medical Center at the University of Munich.
"These findings provide a new standard treatment option and we believe they are likely to change the way many specialists treat these tumors," he tells WebMD.
The results were presented at a joint meeting of the European Cancer Organization and the European Society of Medical Oncology.
Soft tissue sarcomas involve tumors that start in the soft, supporting tissues of the body, such as muscle, fat, blood vessels, nerves, tendons, tissue around the joints, and deep layers of the skin. They are relatively rare, accounting for about 3% of all cancers, but are more common in children and young adults.
However, the benefits of chemotherapy have been shown to be limited, Issels says, and high-risk patients often relapse within two or three years.
Targeted Heat Therapy: How It Works
That's where targeted heat therapy comes in. The technique, known as regional hyperthermia, uses focused electromagnetic energy to warm the tissue in and around the tumor to between 104 and 109.4 degrees Fahrenheit.
The heat packs a four-pronged attack against the tumor, says Gerard C. van Rhoon, PhD, head of the hyperthermia unit at Erasmus University Medical Center in Rotterdam, Netherlands.
The improved blood flow also brings more oxygen to the tumor, which makes it more sensitive to radiation. Finally, the heat interferes with cancer cells' repair mechanisms and they die off, van Rhoon tells WebMD.
The new study involved 341 patients being treated for locally advanced soft tissue sarcomas that were at high risk of recurrence and spread.
All patients were given chemotherapy before and after surgery and radiation treatment afterward. Half were randomly assigned to targeted heat treatment along with the chemotherapy. Then they were followed for an average of nearly three years.
"Patients receiving the targeted therapy fared better on all the outcome measures," Issels says. Among the findings:
- Patients who got heat therapy were 42% less likely to experience a recurrence of their cancer at the same site or to die than those who did not.
- Heat-treated patients were 30% less likely to experience any recurrence or spread of cancer or to die.
- The average length of time that patients remained disease free was 32 months in the group that got heat treatments, compared with 18 months in the group that did not -- an improvement of 30%.
In an analysis of the 269 patients who completed all their treatments, those given heat therapy were 66% less likely to die than those who did not get heat treatment.
The technique is only offered at a handful of clinics and hospitals in Germany, the Netherlands, Switzerland, and Norway, Issels says.
The new findings bolster the case for exploring the strategy in other types of tumors, he says, adding that is has already shown promise for recurrent breast and locally advanced cervical cancer. It's also been shown to work in bladder cancer, van Rhoon says.
The most frequent side effect of the heat therapy was mild to moderate discomfort, reported by 45% of patients. The most serious side effect was severe burns, seen in one patient. Blisters occurred in 17.8% of patients.