A novel strategy of radiofrequency hyperthermia (neothermia) in combination with preoperative chemoradiotherapy for the treatment of advanced rectal cancer: a pilot study

作者：Shoji Hisanori^*; Motegi Masahiko; Osawa Kiyotaka; Okonogi Noriyuki; Okazaki Atsushi; Andou Yoshitaka; Asao Takayuki; Kuwano Hiroyuki; Takahashi Takeo; Ogoshi Kyoji

来源：Cancer Medicine, 2015, 4(6): 834-843.

DOI：10.1002/cam4.431

• 8MHz radiofrequency capacitive heating device
• capecitabine
• hyperthermia
• intensity-modulated radiotherapy
• rectal cancer
• reference point

The safety of weekly regional hyperthermia performed with 8MHz radiofrequency (RF) capacitive heating equipment has been established in rectal cancer. We aimed to standardize hyperthermia treatment for scientific evaluation and for assessing local tumor response to RF hyperthermia in rectal cancer. Forty-nine patients diagnosed with rectal adenocarcinoma were included in the study. All patients received chemoradiation with intensity-modulated radiation therapy 5days/week (dose, 50Gy/25 times) concomitant with 5days/week for five times of capecitabine (1700mg/m(2) per day) and once a week for five times of 50min irradiations by an 8MHz RF capacitive heating device. Thirty-three patients underwent surgery 8weeks after treatment. Three patients did not undergo surgery because of progressive disease (PD) and 13 refused. Eight (16.3%) patients had a pathological complete response (ypCR) after surgery. Among patients without surgery, 3 (6.1%) had clinical complete response (CR) and 3 (6.1%) had local CR but distant PD (CRPD). Ninety percent of ypCR+CR patients were shown in 6.21Wmin(-1)m(-2)/treatment or higher group of average total accumulated irradiation output with 429 degrees Cmin(-1)m(-2) or higher group of total accumulated thermal output. However, a patient with CRPD was in the higher total accumulated thermal output group. We propose a new quantitative parameter for the hyperthermia and demonstrated that patients can benefit from mild irradiation with mild temperature. Using these parameters, the exact output, optimal thermal treatment, and contraindications or indications of this modality could be determined in a multi-institutional, future study.

• 出版日期2015-6