Pilot study of local hyperthermia, radiation therapy, etanidazole, and cisplatin for advanced superficial tumours

Heat Shock Protein translocation induced by membrane fluidization increases tumor-cell sensitivity to chemotherapeutic drugs

Treatment of chronic lymphocytic leukemia (CLL) remains a challenge due to the frequency of drug resistance amongst patients. Improving the delivery of chemotherapeutic agents while reducing the expression of anti-apoptotic Heat Shock Proteins (HSPs) within the cancer cells may facilitate in overcoming this drug resistance. We demonstrate for the first time that sub-lethal doses of chemotherapeutic agents can be combined with membrane fluidizing treatments to produce a significant increase in drug efficacy and apoptosis in vitro. We show that fluidizers result in a transient decrease in intracellular HSPs, resulting in increased tumor-cell sensitivity and a membrane-associated induction of HSP gene expression.

A pilot Phase II trial of concurrent radiotherapy, chemotherapy, and hyperthermia for locally advanced cervical carcinoma

BACKGROUND

Five randomized studies have demonstrated a benefit derived from adding cisplatin (CDDP)-based chemotherapy to radiotherapy (RT) for treatment of cervical carcinoma. The Dutch Phase III pelvic tumor trial demonstrated a survival and local control benefit due to the addition of hyperthermia (HT) to RT. The authors evaluated response and toxicity in patients with locally advanced cervical carcinoma (LACC) who were treated with concurrent weekly CDDP, HT, and RT (whole pelvis [n=7] and whole pelvis and paraaortic nodes [n=5]).

METHODS

From August 1998 through December 2000, 12 patients with LACC or locally recurrent cervical carcinoma (LRCC) following hysterectomy were enrolled on a pilot study combining weekly CDDP, HT, and RT.

RESULTS

Ten patients were treated at initial diagnosis. All achieved clinical complete response and durable local control. Two of the 10 experienced recurrence outside the pelvis; 1 of these patients had pulmonary metastasis, and the other had isolated paraaortic nodal involvement. Two patients treated for LRCC experienced local and systemic progression and died of disease within 6 months.

CONCLUSIONS

In this small series, trimodality therapy resulted in an excellent clinical response and was well tolerated. The addition of HT to chemoradiotherapy represents a promising new strategy that warrants multiinstitutional collaborative efforts to confirm its efficacy.

For the clinical application of thermochemotherapy given at mild temperatures

It has been demonstrated in vitro and in vivo that hyperthermia can enhance the cytotoxicity of some chemotherapeutic agents. This paper summarizes the authors' own laboratory studies on the effect of chemotherapeutic agents given at elevated temperatures, experimental results obtained using animal tumour systems in other laboratories, and clinical trials of thermochemotherapy reported in literature. The in vivo studies have demonstrated that the thermal enhancement of cytotoxicity of many chemotherapeutic agents is maximized at mild temperatures such as at 40.5-43 degrees C. Comparison of in vitro and in vivo results using five agents show that the in vivo thermal enhancement increases with an increase in the activation energy obtained in the temperature range between 40.5 and 43.0 degrees C. A summary of experimental results obtained by various investigators indicates a potentially wide variation in the thermal enhancement of a given agent among the different types of tumours and suggests potential agents useful at moderately elevated temperatures. In vivo studies on nine different agents indicate that the drug(s) of choice at physiological temperatures may not be the drug(s) of choice at elevated temperatures. It is also shown that drug concentration in the target must be high for sufficient thermal enhancement. Clinical trials of thermochemotherapy have employed various heating methods, including local heating, hyerthermic perfusion and whole body hyperthermia. Extensive trials have been made in the treatment of melanoma and soft tissue sarcoma in the extremity. Hyperthermic isolated perfusion with chemotherapeutic(s) provides much higher drug concentration than a systemic drug administration in the target(s), resulting in a high tumour response rate and an increased survival of the patients. It is of interest that the most successful agent used in the treatment of both melanomas and sarcomas is melphalan and is the drug of choice at moderately elevated temperatures among the nine agents tested in the in vivo studies. Current results using the tumour necrosis factor with melphalan are impressive. In several institutes, techniques have been developed to uniformly heat the localized tumour, but studies are needed to find an agent effective at elevated temperatures to each type of tumours and to establish the methods for obtaining a sufficient drug concentration in the target tissue.