Recent trends and therapeutic efforts to utilize thermal ablation for treating non-colorectal liver metastases are summarized. Thermal ablation, including microwave coagulation therapy and radiofrequency ablation were utilized for the treatment of liver metastases originating from neuroendocrine tumors, gastric cancer, breast cancer, thyroid cancer, pancreatobiliary cancer, etc. Hepatic resection is a first-line therapy for colorectal liver metastases, but not necessarily for non-colorectal liver metastases. In some patients with non-colorectal liver metastases, an important role of thermal ablation is to provide relief from symptoms and to reduce tumor size in combination with pharmacologic treatment. Local recurrence rates after thermal ablation were 6.3% for liver metastases from neuroendocrine tumors, and 14.7% for colorectal liver metastases. Of 3554 lesions treated, including 693 liver metastases, the mortality and morbidity rates were only 0.3% and 7.2%, respectively. Specific complications in using thermal ablation for non-colorectal liver metastases have never been reported. Excellent median survival times of 49 and 59 months were reported after thermal ablation for neuroendocrine and breast cancer liver metastases, respectively. Gastric cancer liver metastases are often accompanied with extrahepatic metastases and have a poor prognosis. However, if treated with hepatic arterial infusion chemotherapy followed by thermal ablation, the median survival time of 16.5 months was favorable. Thermal ablation has shown a therapeutic impact in the treatment of symptomatic liver-only metastases from neuroendocrine tumors, from a small number of metachronous tumors, a small number of gastric cancer liver metastases, especially when treated with hepatic arterial infusion chemotherapy, and in breast cancer liver metastases without visceral extrahepatic disease. Thermal ablation is a safe and effective procedure for selected non-colorectal liver metastases.

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Heat dissipation characteristics and magnetic properties of iron oxide nanoparticles (IOPs) synthesized by co-precipitation and thermal decomposition are reported. IOPs were successfully synthesized by thermally decomposing iron pentacarbonyl in an atmospheric condition. According to transmission electron microscopy, the particle diameter varied between 3.0 and 12.2 nm depending on the concentration of oleic acid and reaction time. On the other hand, coprecipitated IOPs with an average diameter of 10.2 nm were synthesized by introducing ammonia solution to the aqueous solution of iron sulfate and iron chloride mixture. The heat dissipation characteristics of the isoparaffin dispersion of IOPs were measured by exposing a magnetic field strength and frequency of 3.2 kA/m and 600 kHz respectively. For a specific time, the coprecipitated particles with an average diameter of 10.2 nm exhibited a temperature rise of 77 K, whereas the temperature rise exhibited by particles synthesized by thermal decomposition with an average diameter of 11.3 nm was 14 K. On the other hand, particles with an average diameter of 3.0 nm did not generate significant heat. The magnetic property of the samples, especially the temperature at which the magnetic susceptibility becomes maximum (blocking temperature) was measured using superconducting quantum interference device. The results suggested that the sample with higher blocking temperature generated more heat.

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Salvage treatment (treatment of recurrent or resistant tumors) is difficult in patients with either residual or recurrent cancer after definitive chemoradiotherapy for esophageal cancer. This report presents the first case of a patient, for whom hyperthermo-chemotherapy was markedly effective for recurrent cervical esophagus cancer after definitive chemoradiotherapy (CRT). The patient was a 66-year-old female, in whom an elevated cervical tumor was detected 10 years after an endoscopic mucosal resection for mid-thoracic esophageal cancer (cT1aN0M0 Stage I based on standards of the Japan Esophageal Society). The tumor was diagnosed to be a secondary primary squamous cell carcinoma of the cervical esophagus (cT2N1M0 Stage II). Definitive chemo-radiotherapy (a total 75.4 Gy of radiation plus docetaxel) resulted in a complete response. However, a local recurrence was recognized five months later. Although chemotherapy with nedaplatin and 5-FU was performed for 6 months, the recurrent tumor enlarged. Oral S-1 (100 mg/day) chemotherapy was administered on days 1-28 every 6 weeks. Concurrent with S-1, local hyperthermia delivered with a Thermotron RF-8 (50 minutes) was performed on days 1, 8, 15, and 22, every 6 weeks. After the first course of treatment, the tumor disappeared, and this treatment was repeated for 5 cycles on an outpatient basis without any critical side effects. The clinical course of this case suggests that hyperthermo-chemotherapy is a potent salvage treatment for either remnant or recurrent esophageal cancer disease after definitive CRT.

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