Radiotherapy Of Head Tumors Research Articles

The pilot study of on-site end-to-end IMRT audit in radiotherapy in the Czech Republic with the head anthropomorphic phantom

Introduction In the Czech Republic, intensity modulated radiation therapy (IMRT) became a standard type of treatment. Each department has established the quality controls for IMRT plans but these controls can miss some aspects because they are not “end-to-end” tests. National Radiation Protection Institute (NRPI) has developed a tool for comprehensive verification of IMRT head plans. Purpose The aim of this work was to propose and test on-site audit that would verify the whole process of radiotherapy of head tumors. Materials and methods Anthropomorphic head phantom including bones, soft tissues, and cavities was adjusted for the purposes of the audit. Apertures for chambers were drilled and volumes were marked out in the phantom to distinguish PTV and OARs unambiguously. Two treatment sites can be verified separately (nasopharynx and glioblastoma). Verification of point doses with ionisation chambers and planar doses with films in PTV and organ at risk can be performed as well as planning process control. Results Methodology has been tested within the pilot study at 3 departments with photon beams (including rotational techniques) and one department with proton beams. The audit can be performed globally. The results might show interesting intercomparison among departments covering dosimetry part of treatment as well as differences in contouring standards, planning standards, plan evaluation parameters, patient set-up accuracy. Conclusion NRPI has developed and tested methodology of “end-to-end” audit for head and brain IMRT treatment. Disclosure This work has been supported by the project No. TB04SUJB001. Authors have no potential conflict of interest to disclose.

Loss of BRCC3 Deubiquitinating Enzyme Leads to Abnormal Angiogenesis and Is Associated with Syndromic Moyamoya

Moyamoya is a cerebrovascular angiopathy characterized by a progressive stenosis of the terminal part of the intracranial carotid arteries and the compensatory development of abnormal and fragile collateral vessels, also called moyamoya vessels, leading to ischemic and hemorrhagic stroke. Moyamoya angiopathy can either be the sole manifestation of the disease (moyamoya disease) or be associated with various conditions, including neurofibromatosis, Down syndrome, TAAD (autosomal-dominant thoracic aortic aneurysm), and radiotherapy of head tumors (moyamoya syndromes). Its prevalence is ten times higher in Japan than in Europe, and an estimated 6%-12% of moyamoya disease is familial in Japan. The pathophysiological mechanisms of this condition remain obscure. Here, we report on three unrelated families affected with an X-linked moyamoya syndrome characterized by the association of a moyamoya angiopathy, short stature, and a stereotyped facial dysmorphism. Other symptoms include an hypergonadotropic hypogonadism, hypertension, dilated cardiomyopathy, premature coronary heart disease, premature hair graying, and early bilateral acquired cataract. We show that this syndromic moyamoya is caused by Xq28 deletions removing MTCP1/MTCP1NB and BRCC3. We also show that brcc3 morphant zebrafish display angiogenesis defects that are rescued by endothelium-specific expression of brcc3. Altogether, these data strongly suggest that BRCC3, a deubiquitinating enzyme that is part of the cellular BRCA1 and BRISC complexes, is an important player in angiogenesis and that BRCC3 loss-of-function mutations are associated with moyamoya angiopathy.

Orodental Care related to Radiotherapy for Head and Neck Cancer

ABSTRACTOrodental care is mandatory in radiotherapy for head and neck cancer patients. Radiation therapy of malignant tumors of head and neck is associated with number of side effects, which can lead to acute and chronic oral complications. It is important to prevent and treat orofacial complications which require a multidisciplinary approach. All patients should undergo oral screening before radiotherapy for tumors of head and neck. Many oral conditions, such as poor oral hygiene, broken teeth, defective restorations and periodontal disease, are likely to precipitate complications during and after a course of radiation therapy and it is always better to deal with these problems before starting radiotherapy. The risk of osteoradionecrosis will be reduced to zero if there was a 21-day or greater interval between extraction and initiation of radiation therapy. Systematically applied oral hygiene protocols during radiotherapy may reduce the incidence, severity and duration of oral complications. It is well accepted that tooth extraction should be avoided even after many years of head and neck radiotherapy. If required it should be done by an experienced dental surgeon with proper prophylactic measures. The dental professional plays a relevant role in the prevention and healing or control of the oral complications. The relief of symptoms and the eradication of clinical manifestations largely improve patient quality of life.