Background: Previous studies have reported synergistic effects of combined hyperthermia and chemotherapy and/or irradiation. The discussed underlying mechanism for this effect is an synergistic cytotoxic and radiosensitizing effect of hyperthermia. In addition, tumor blood-flow and, consequently, tumor oxygenation are increased during hyperthermia. Tumor response to irradiation and chemotherapy of well-oxygenated and vascularized tumors, in general, is superior to that of hypoxic tumors. Therefore, tumor oxygenation is recognized as an important predictive factor in the therapy of malignant tumors. Technically, the head-neck area remains outside the hyperthermia chamber during whole-body hyperthermia (WBH) as currently applied in a number of cancer treatment regimens. The aim of this therapeutic approach was to evaluate whether the blood flow during WBH also increased in the head-neck region and, if so, whether tumor oxygenation increase accordingly.
Methods: A 60-year-old male Caucasian patient, with the original diagnosis of pT3 pN2b M0 squamous cell carcinoma of the oral cavity, who had undergone primary surgery and irradiation (total dose 60 Gy), developed three local recurrences with consecutive surgical resection, presenting now with another recurrent local tumor (histologically confirmed) without surgical or radiotherapeutical options due to lymphangiosis carcinomatosa. WBH was applied under full anaesthesia, using a humidified radiant heat device (Enthermics Medical Systems RHS-7500) in combination with synchronous application of chemotherapy (ifosfamide and carboplatin). Four cycles of this combined treatment (one cycle per month) were given. Tumor oxygenation and temperature were continuously monitored by Licox catheters by means of one point measurement during each treatment (3.5 h).
Results: With a latency of 10 min, the increase of intratumoral temperature in the oral cavity was comparable to reference values in the esophagous. Maximum intratumoral temperature (oral cavity) was 41.8 degrees C (F). The average increase of tumor oxygenation was more than 100% in each individual cycle. Clinically, a partial tumor response was observed.
Conclusions: During combined WBH and polychemotherapy, oxygenation is also significantly improved in a tumor in the head and neck area despite the fact that head and neck area remains outside the hyperthermia chamber during WBH. Intratumoral temperatures achieved are comparable to esophageal and rectal temperatures obtained during WBH.