Background: Hyperthermia has not been approved as a standard treatment method in oncology. One of the major problems is that there is no reference point for this therapy. Another problem is that radiofrequency hyperthermia has a fatal flaw, the hot spot phenomenon, which does not allow continuation of treatment without lowering the output.
Patients and Methods: Hyperthermia treatment was administered either alone or concomitantly with chemotherapy and/or radiotherapy to 76 consecutive patients with malignancies, using Thermotron RF-8, between December 2011 and April 2014. Radiofrequency hyperthermia was administered 5 times for 5 weeks with 50 min irradiation in all patients.
Results: Complete response (CR) was seen in 35.2% of primary cases, but in 4.5% of recurrent cases, and this rate was higher in patients with three days after first chemoradiation. There was significant correlation among the initial irradiation output at which complications occurred, initial time at which complications occurred and the physical status of the patients, such as visceral fat area. All patients with CR had significantly higher increased body temperature than the other patients. However, patients with progressive disease and 17 or more Hidaka output points showed significantly higher increased body temperature than patients with partial response or stable disease.
Conclusions: Patients with CR had higher temperatures, but some patients with higher temperature also showed progressive disease. Further studies to examine the discrepancy between the clinical and histological response by using a large sample of surgically resected cases and to validate and reconfirm our findings are warranted.