Salvage Re-irradiation with Intensity-modulated Radiotherapy, Chemotherapy Combined with Hyperthermia for Local Recurrence of Nasopharyngeal Carcinoma After Chemoradiotherapy.

A sufficient dose of radiation is difficult to administer in re-irradiation for local recurrence of cancer after radiotherapy because of the dose limitation to organs at risk. Re-irradiation cases also include radioresistant tumors that are difficult to control locally, and their prognosis is poor in general. The effect of re-irradiation using intensity-modulated radiotherapy (IMRT) has recently been reported to significantly reduce the dose to organs at risk, and the efficacy of hyperthermia has been reported for radioresistant tumors. We report a case of local recurrence after concurrent chemoradiotherapy treated with salvage re-irradiation using IMRT and chemotherapy combined with hyperthermia in a patient with nasopharyngeal carcinoma, and include a discussion of the literature.

Pembrolizumab-induced Radiation Recall Pneumonitis After the Resolution of Typical Asymptomatic Radiation Pneumonitis.

Radiation recall pneumonitis is a phenomenon in which a recall-triggering drug induces an acute inflammatory reaction in the lungs, corresponding to a previously irradiated area. Radiation recall reactions have been reported to occur following treatments with various cytotoxic anticancer agents and molecular-targeting drugs; however, only a few reports have described immune checkpoint inhibitor-induced radiation recall pneumonitis. We report a case of radiation recall pneumonitis induced by pembrolizumab in a patient with the postoperative local recurrence of non-small cell lung cancer. This case demonstrated that pembrolizumab might cause severe radiation recall pneumonitis, even after typical radiation pneumonitis has been resolved.

The usefulness of mobile insulator sheets for the optimisation of deep heating area for regional hyperthermia using a capacitively coupled heating method: phantom, simulation and clinical prospective studies.

PURPOSE: To evaluate the feasibility and efficacy of deep regional hyperthermia with the use of mobile insulator sheets in a capacitively coupled heating device. MATERIALS AND METHODS: The heat was applied using an 8-MHz radiofrequency-capacitive device. The insulator sheet was inserted between the regular bolus and cooled overlay bolus in each of upper and lower side of the electrode. Several settings using the insulator sheets were investigated in an experimental study using an agar phantom to evaluate the temperature distributions. The specific absorption rate (SAR) distributions in several organs were also computed for the three-dimensional patient model. In a clinical prospective study, a total of five heating sessions were scheduled for the pelvic tumours, to assess the thermal parameters. The conventional setting was used during the first, third and fifth treatment sessions, and insulator sheets were used during the second and fourth treatment sessions. RESULTS: In the phantom study, the higher heating area improved towards the centre when the mobile insulator sheets were used. The subcutaneous fat/target ratios for the averaged SARs in the setting with the mobile insulator (median, 2.5) were significantly improved compared with those in the conventional setting (median, 3.4). In the clinical study, the thermal dose parameters of CEM43°CT90 in the sessions with the mobile insulator sheets (median, 1.9 min) were significantly better than those in the sessions using a conventional setting (median, 1.0 min). CONCLUSIONS: Our novel heating method using mobile insulator sheets was thus found to improve the thermal dose parameters. Further investigations are expected.

Intensity-Modulated Radiotherapy with Regional Hyperthermia for High-Risk Localized Prostate Carcinoma.

BACKGROUND: The purpose of this study was to evaluate the efficacy and toxicity of adding regional hyperthermia to intensity-modulated radiotherapy (IMRT) plus neoadjuvant androgen deprivation therapy (ADT) for high-risk localized prostate carcinoma. METHODS: Data from 121 consecutive patients with high-risk prostate carcinoma who were treated with IMRT were retrospectively analyzed. The total planned dose of IMRT was 76 Gy in 38 fractions for all patients; hyperthermia was used in 70 of 121 patients. Intra-rectal temperatures at the prostate level were measured to evaluate thermal dose. RESULTS: Median number of heating sessions was five and the median total thermal dose of CEM43T90 was 7.5 min. Median follow-up duration was 64 months. Addition of hyperthermia to IMRT predicted better clinical relapse-free survival. Higher thermal dose with CEM43T90 (>7 min) predicted improved biochemical disease-free survival. The occurrence of acute and delayed toxicity ≥Grade 2 was not significantly different between patients with or without hyperthermia. CONCLUSIONS: IMRT plus regional hyperthermia represents a promising approach with acceptable toxicity for high-risk localized prostate carcinoma. Further studies are needed to verify the efficacy of this combined treatment.

Optimization of the Clinical Setting Using Numerical Simulations of the Electromagnetic Field in an Obese Patient Model for Deep Regional Hyperthermia of an 8 MHz Radiofrequency Capacitively Coupled Device in the Pelvis.

Background: The purpose of this study was to evaluate the effectiveness of the clinical setting for deep regional hyperthermia of an 8 MHz radiofrequency (RF) capacitively coupled device in the pelvis by using numerical simulations of the electromagnetic field. Methods: A three-dimensional patient model of cervical cancer of the uterus in an obese patient was reconstructed with computed tomography data. The specific absorption rate (SAR) and temperature distributions among the various heating settings were evaluated using numerical simulations. Results: The averaged SAR value of the deep target tumor was similar between with or without overlay boluses (OBs), and that of the subcutaneous fat (SF) at the edges of cooling boluses with OBs was lower than that of the SF without OBs. The use of OBs reduced the overheating of the SF. The 0.5% salt solution in the OB produced the least overheated areas outside the deep target tumor compared with the other concentrations. The insertion of the intergluteal cleft (IGC) bolus could improve the temperature concentration of the deep target tumor. Conclusions: The use of OBs and the salt solution concentration in the OB were important to optimize the temperature distribution. IGC bolus might contribute to temperature optimization. Further studies with individualized numerical simulations in each patient are expected.

Pediatric nasopharyngeal cancer with repeated oligometastases involving the bone, liver and distant lymph nodes who achieved cure after radiotherapy.

Systemic chemotherapy is a standard treatment for Stage IVc nasopharyngeal carcinoma (NPC). Stage IVc NPC patients with oligometastases have a better prognosis, and local therapy has an important role in further development of the disease. However, the efficacy of local therapy to the metastases in patients with multiple-site and/or multiple-organ metastases is limited due to the aggressive behavior of the tumor. We report a NPC case in a pediatric patient with repeated oligometastases involving the bone, liver and distant lymph nodes who achieved 10-year disease free status after initial chemotherapy and radiotherapy to all the metastases. This very rare case demonstrated that radiotherapy to oligometastatic lesions have a potential to cure repeated oligometastases which involved multiple-organ metastases in a pediatric NPC with stage IVc.