High dose hypofractionated proton beam therapy is a safe and feasible treatment for central lung cancer

Background There have been few reports about high total dose hypofractionated proton beam therapy for central lung cancer. The aim of this study was to examine retrospectively the safety and efficacy of high total dose hypofractionated proton beam therapy for central lung cancer. Patients and methods Patients treated by proton beam therapy for central lung cancer located less than 2 cm from the trachea, mainstem bronchus, or lobe bronchus were included in this study. All patients received 80 Gy of relative biological dose effectiveness (RBE) in 25 fractions with proton beam therapy over 5 weeks between January 2009 and February 2015. The toxicities were evaluated using the Radiation Therapy Oncology Group and European Organization for Research and Treatment of Cancer criteria. Results Twenty patients, including 14 clinically inoperable patients (70%), received proton beam therapy for central lung cancer. The median patient age was 75 years (range: 63–90 years), the median follow up time was 27.5 months (range: 12–72 months), and the median tumor diameter was 39.5 mm (range: 24–81 mm). All patients were followed for at least 20 months or until death. The 2-year overall survival rate was 73.8% (100% in operable patients, and 62.5% in inoperable patients), and the 2-year local control rate was 78.5%. There was no Grade 3 or higher toxicities, including bronchial stricture, obstruction, and fistula. Conclusions The present study suggests that a high total dose hypofractionated proton beam therapy for central lung cancer was safe and feasible.

Application of Pelletron Accelerator to Study High Total Dose Radiation Effects on Semiconductor Devices

Silicon bipolar junction transistors (BJTs), Silicon-germanium heterojunction bipolar transistors (SiGe HBTs) and metal oxide semiconductor (MOS) devices are the key components of BiCMOS integrated circuits. The semiconductor devices need to withstand very high total doses (100’s of Mrad) for reliable operation of electronic circuits for 8-10 years of LHC operation. The study of radiation tolerance of semiconductor devices up to 100 Mrad of total dose takes longer time with conventional 60Co gamma, proton and electron irradiation facilities and the effects due to these radiations are well understood. Hence it is important to study the effects of heavy ion irradiation on various semiconductor devices. The irradiation time decreases with increasing linear energy transfer (LET) of incident radiation and LET increases with atomic number of the impinging ions. But it is essential to understand the mechanism of energy transfer by different heavy ions in semiconductor devices. Therefore, here we give an overview of different heavy ion interactions with Si BJTs, MOSFETs and SiGe HBTs by primarily focusing on the electrical characteristics of these devices before and after ion irradiation. We show that the irradiation time needed to reach very high total dose can be reduced by using Pelletron accelerator facilities instead of conventional irradiation facilities.

An Intraoperative Case of Spontaneous Restoration of Circulation from Asystole: A Case of Lazarus Phenomenon

This case report refers to a victim of intraoperative cardiac arrest, who restored spontaneous circulation despite of cessation of cardiopulmonary resuscitation (CPR). The victim, a 53-year-old man, was undergoing a surgical investigation and rehabilitation of a thigh hematoma. Two minutes after discontinuation of a 46 min CPR, a normotensive sinus node rhythm appeared at monitor. Despite of lack of an adequate explanation, the authors believe that the combination of the high total dose of adrenaline with the cessation of mechanical ventilation might augment venous return and lead to restoration of spontaneous circulation.