Dosimetric comparison in sparing normal tissue dosage by using auto-SBRT planning in oligo liver tumors.

Purpose: The study aimed to compare the dosimetric distribution of VMAT plans by increasing the number of half arcs in liver SBRT and investigate the effect by using automatic plan software in plan optimization. Method: Thirty-one patients with oligo liver tumors were randomly selected. VMAT treatment plans with different numbers of coplanar half arcs were generated. Result: Adding arcs significantly increased the PTV, D2%, D50%, and CI, but sacrificed the plan homogeneity. It also decreased the maximum dose of normal tissues such as the stomach, duodenum, and spinal cord and reduced Dmean, D500cc, and D700cc for the liver. Nevertheless, the diminishing effect gradually decayed into three arcs. Meanwhile, the addition of arcs substantially extended the beam-on time. Conclusion: In the context of SBRT for oligo liver tumors, increasing the number of coplanar half arcs will improve PTV conformity and offer better protection for OARs, albeit at the expense of increased treatment duration. Considering the trade-off between plan quality and treatment efficiency, a three-arc plan may be more suitable for clinical implementation.

Advancements of radiotherapy for recurrent head and neck cancer in modern era.

Head and neck cancer is a kind of cancer which can be eradicated from radical radiation therapy. However, with best efforts, nearly 40% patients will experience locoregional recurrence. Locoregional recurrence is the main cause of cancer-related death in head and neck cancers, so local treatments play a key role in improving progression free survival. In the last decades, radiation techniques have been tremendously developed, highly conformal radiation techniques such as intensity-modulated radiotherapy, stereotactic body radiation therapy, brachytherapy and proton or heavy ion radiation therapy have their unique radiobiological advances. Although reirradiation is widely used in clinical practice, but little is known when comparing the different techniques. In this review, we will provide a comprehensive overview of the role of reirradiation in recurrent head and neck cancers including radiation techniques, patient selection, overall clinical benefits, and toxicities.

Use of a Titanium Cage and Intramedullary Nails to Treat Distal Femoral Fracture Nonunion in a Patient with Renal Osteopathy: A Case Report.

BACKGROUND Nonunion occurs to approximately 10% of people who suffer from distal femoral fracture, which can be induced by other diseases and medical interventions. CKD and subsequent renal osteopathy are regarded as risk factors for nonunion. Internal fixation is the most widely applied medical procedure to treat distal femoral fracture, the efficiency and stability of which are improved by emerging biological materials. Besides traditional screws and plate, titanium cages and intramedullary nails have been introduced lately to repair nonunion and large bone defects resulting from it, which is a huge challenge for orthopedic surgeons. To the best of our knowledge, this is the first report on a distal femoral fracture patient with renal osteopathy treated by internal fixation enhancement using a titanium cage and intramedullary nails. CASE REPORT We report the case of an 84-year-old Chinese woman with renal osteopathy who underwent 4 internal fixation operations to treat a distal femoral fracture. The first 3 surgeries used screws and a plate as internal fixation materials to treat the fracture and nonunion, but did not achieve satisfactory outcomes. In the final surgery, a titanium cage and intramedullary nail were used and the patient recovered soon. CONCLUSIONS Doctors should pay attention to patient's primary health conditions, especially renal disorders, before performing surgeries for distal femoral fracture. It is important to select the most appropriate materials and choose the most suitable surgical method in patients with poor health conditions.