This document is the report of a task group of the AAPM and has been prepared primarily to advise medical physicists involved in the external-beam radiation therapy of patients with thoracic, abdominal, and pelvic tumors affected by respiratory motion. This report describes the magnitude of respiratory motion, discusses radiotherapy specific problems caused by respiratory motion, explains techniques that explicitly manage respiratory motion during radiotherapy and gives recommendations in the application of these techniques for patient care, including quality assurance (QA) guidelines for these devices and their use with conformal and intensity modulated radiotherapy. The technologies covered by this report are motion-encompassing methods, respiratory gated techniques, breath-hold techniques, forced shallow-breathing methods, and respiration-synchronized techniques. The main outcome of this report is a clinical process guide for managing respiratory motion. Included in this guide is the recommendation that tumor motion should be measured (when possible) for each patient for whom respiratory motion is a concern. If target motion is greater than 5 mm, a method of respiratory motion management is available, and if the patient can tolerate the procedure, respiratory motion management technology is appropriate. Respiratory motion management is also appropriate when the procedure will increase normal tissue sparing. Respiratory motion management involves further resources, education and the development of and adherence to QA procedures.

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Purpose Glioblastoma multiforme (GBM) is the most common primary brain tumor in adults, and radiation is one of the main treatment modalities. However, cure rates remain low despite best available therapies. Immunotherapy is a promising modality that could work synergistically with radiation, which has been shown to increase antigen presentation and promote a proinflammatory tumor microenvironment. Programmed-death-1 (PD-1) is a surface receptor expressed on activated and exhausted T cells, which mediate T cell inhibition upon binding with its ligand PD-L1, expressed on many tumor types including human GBMs. We tested the combination of anti-PD-1 immunotherapy with stereotactic radiosurgery in a mouse orthotopic GBM model. Methods and Materials We performed intracranial implantation of mouse glioma cell line GL261 transfected with luciferase into C57BL/6 mice. Mice were stratified into 4 treatment groups: (1) control; (2) radiation only; (3) anti-PD-1 antibody only; and (4) radiation plus anti-PD-1 antibody. Overall survival was quantified. The mice were killed on day 21 after implantation to assess immunologic parameters in the brain/tumor, cervical lymph nodes, and spleen. Results Improved survival was demonstrated with combination anti-PD-1 therapy plus radiation compared with either modality alone: median survival was 25 days in the control arm, 27 days in the anti-PD-1 antibody arm, 28 days in the radiation arm, and 53 days in the radiation plus anti-PD-1 therapy arm (P<.05 by log-rank Mantle-Cox). Long-term survival was seen only in the combined treatment arm, with a fraction (15%–40%) of animals alive at day 180+ after treatment. Immunologic data on day 21 after implantation showed increased tumor infiltration by cytotoxic T cells (CD8+/interferon-γ+/tumor necrosis factor-α+) and decreased regulatory T cells (CD4+/FOXP3) in the combined treatment group compared with the single modality arms. Conclusions The combination of PD-1 blockade and localized radiation therapy results in long-term survival in mice with orthotopic brain tumors. These studies provide strong preclinical evidence to support combination trials in patients with GBM.

ObjectiveA prospective randomized study was undertaken to compare early with delayed laparoscopic cholecystectomy for acute cholecystitis. Summary Background DataLaparoscopic cholecystectomy for acute cholecystitis is associated with high complication and conversion rates. It is not known whether there is a role for initial conservative treatment followed by interval elective operation. MethodDuring a 26-month period, 99 patients with a clinical diagnosis of acute cholecystitis were randomly assigned to early laparoscopic cholecystectomy within 72 hours of admission (early group, n = 49) or delayed interval surgery after initial medical treatment (delayed group, n = 50). Thirteen patients (four in the early group and nine in the delayed group) were excluded because of refusal of operation (n = 6), misdiagnosis (n = 5), contraindication for surgery (n = 1), or loss to follow-up (n = 1). ResultsEight of 41 patients in the delayed group underwent urgent operation at a median of 63 hours (range, 32 to 140 hours) after admission because of spreading peritonitis (n = 3) and persistent fever (n = 5). Afthough the delayed group required less frequent modifications in operative technique and a shorter operative time, there was a tendency toward a higher conversion rate (23% vs. 11 %; p = 0.174) and complication rate (29% vs. 13%; p = 0.07). For 38 patients with symptoms exceeding 72 hours before admission, the conversion rate remained high after delayed surgery (30% vs. 17%; p = 0.454). In addition, delayed laparoscopic cholecystectomy prolonged the total hospital stay (11 days vs. 6 days; p < 0.001) and recuperation period (19 days vs. 12 days; p < 0.001). ConclusionsInitial conservative treatment followed by delayed interval surgery cannot reduce the morbidity and conversion rate of laparoscopic cholecystectomy for acute cholecystitis. Early operation within 72 hours of admission has both medical and socioeconomic benefits and is the preferred approach for patients managed by surgeons with adequate experience in laparoscopic cholecystectomy.Although recent studies1-6 have reported that laparoscopic cholecystectomy is a safe and effective treatment for acute cholecystitis, the optimal timing for the procedure remains unknown. In the prelaparoscopic era, prospective randomized studies7 8 demonstrated that early open cholecystectomy within 7 days of the onset of symptoms was superior to delayed interval surgery because of a shorter total hospital stay and recuperation period. The same economic advantage should also apply if early surgery can be accomplished with the laparoscopic technique. However, the potential hazard of severe complications and the high conversion rate of laparoscopic cholecystectomy in the phase of acute inflammation is a major concern.9"10 Theoretically, conservative treatment with antibiotics followed by interval elective operation several weeks after the acute inflammation subsides may result in a safer operation with a lower conversion rate. Koo and Thirlby11 suggested that there was a role for del...

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The number of lymph nodes removed is an independent predictor of survival after esophagectomy for cancer. To maximize this survival benefit a minimum of 23 regional lymph nodes must be removed.

ObjectiveThe authors report their experience with living donor liver transplantation (LDLT) using extended right lobe grafts for adult patients under high-urgency situations. Summary Background DataThe efficacy of LDLT in the treatment of children has been established. The major limitation of adult-to-adult LDLT is the adequacy of the graft size. A left lobe graft from a relatively small volunteer donor will not meet the metabolic demand of a larger recipient. MethodsFrom May 1996 to November 1996, seven LDLTs, using extended right lobe grafts, were performed under high-urgency situations. All recipients were in intensive care units before transplantation with five having acute renal failure, three on mechanical ventilation, and all with hepatic encephalopathy. The median body weight for the donors and recipients was 58 kg (range, 41-84 kg) and 65 kg (range, 53-90 kg), respectively. The body weights of four donors were less than those of the corresponding recipients, and the lowest donor-torecipient body weight ratio was 0.62:1. The extended right lobe graft was chosen because the left lobe volume was <40% of the ideal liver mass of the recipient. ResultsMedian blood loss for the donors was 900 mL (range, 700-1600 mL) and hospital stay was 19 days (range, 8-22 days). Homologous blood transfusion was not required. Two donors had complications (one incisional hernia and one bile duct stricture) requiring reoperation after discharge. All were well with normal liver function 5 to 10 months after surgery. The graft weight ranged from 490 g to 1 140 g. All grafts showed immediate function with normalization of prothrombin time and recovery of conscious state of the recipients. There was no vascular complication, but six recipients required reoperation. One recipient died of systemic candidiasis 16 days after transplantation and 6 (86%) were alive with the original graft at a median follow-up of 6.5 months (range, 5-10 (range, 53-90 kg). The body weights of four donors were less than those of the corresponding recipients and the lowest donor-to-recipient body weight ratio was 0.62:1 (donor, 41 kg; recipient, 66 kg). Pretransplant ManagementThe evaluation and management followed the same protocol as for any patient who was considered for transplantation in high-urgency status. All seven patients required admission to the intensive care unit before transplantation. In each case, moderate-to-severe hepatic encephalopathy was evident (Table 1) Surgical ProceduresThe donor hepatectomy (Fig. IA) consisted of an extended right lobectomy performed through a bilateral subcostal incision with median extension to the xyphoid. To avoid homologous blood transfusion, autologous blood was collected from the donor on induction of anesthesia, and a cell saver was used to collect blood lost during operation. Intraoperative ultrasound examination was performed to identify the major vascular structures of the liver. Special attention was paid to the anatomy of the junction of the middle and left hepatic veins and the possible existenc...

Purpose-To demonstrate the CT imaging, conformal irradiation and treatment planning capabilities of a small animal radiation research platform (SARRP).Methods-The SARRP employs a dual-focal spot, constant voltage x-ray source mounted on a gantry with a source-to-isocenter distance of 35 cm. Gantry rotation is limited to 120° from vertical. Eighty to 100 kVp x-rays from the smaller 0.4 mm focal spot are used for imaging. Both 0.4 mm and 3.0 mm focal spots operate at 225 kVp for irradiation. Robotic translate/rotate stages are used to position the animal. Cone-beam (CB) CT imaging is achieved by rotating the horizontal animal between the stationary x-ray source and a flat-panel detector. Radiation beams range from 0.5 mm in diameter to (60 × 60) mm 2 . Dosimetry is measured with radio-chromic films. Monte Carlo dose calculations are employed for treatment planning. The combination of gantry and robotic stage motions facilitate conformal irradiation.Results-The SARRP spans 3 ft × 4 ft × 6 ft (WxLxH). Depending on filtration, the isocenter dose outputs at 1 cm depth in water range from 22 to 375 cGy/min from the smallest to the largest radiation fields. The 20% to 80% dose fall-off spans 0.16 mm. CBCT with (0.6 × 0.6 × 0.6) mm 3 voxel resolution is acquired with less than 1 cGy. Treatment planning is performed at sub-mm resolution.Conclusions-The capability of the SARRP to deliver highly focal beams to multiple animal model systems provides new research opportunities that more realistically bridge laboratory research and clinical translation.