[Radiation induced brachial plexopathy: Diagnosis, risk factors, principles of care]. / La plexite radique : épidémiologie, diagnostic, facteurs de risque et prise en charge.

Radiation plexitis, also known as radiation-induced brachial neuropathy is a rare toxicity following axillary, breast, cervical or thoracic radiotherapy, first described in 1966 by Stoll and Andrew. Although improvements in radiotherapy techniques have greatly reduced its risk over the past seventy years, its severe form remains a dreaded complication that is difficult to manage in patients with increased life expectancy. This article summarizes the epidemiological elements, risk factors, diagnostic methods, doses and constraints to be respected in radiotherapy and the treatment strategies of radiation plexitis.

[Low dose radiotherapy for COVID-19 pneumopathy: Biological rationale and literature review]. / Radiothérapie de faible dose pour la pneumopathie covid-19 : rationnel biologique et revue de la littérature.

The world has now been facing the coronavirus disease 2019 (COVID-19) pandemic due to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) since over a year. If most of clinical presentations are benign, fragile patients are at greater risk of developing severe or fatal lung disease. Many therapies have been explored with very low impact on mortality. In this context, Kirkby et Mackenzie have published in April 2020 a report reminding the anti-inflammatory properties of low-dose radiotherapy (delivering less than 1Gy) and its use in the treatment of viral and bacterial pneumopathies before antibiotics era. Large in vivo and in vitro data have demonstrated the biological rationale and anti-inflammatory activity of low-dose radiotherapy in many pathologies. Over the past year, three phase I/II clinical trials have been published, as well as one randomized controlled trial, reporting the feasibility and the clinical and biological improvement of a 0.5 to 1Gy treatment dose to the entire lung. 13 other studies, including a randomized phase III trial, are currently ongoing worldwide. These studies may provide data in the effect of low-dose radiotherapy in the treatment of SARS-CoV-2 pneumonia. This article explains biological rationale of low-dose radiotherapy, and reports already published or ongoing studies on low-dose radiotherapy for SARS-CoV-2 pneumonia.

[Interobserver variability study for daily cone beam computed tomography registration of prostate volumetric modulated arc therapy]. / Tomographie conique quotidienne pour les traitements pelviens et prostatiques: étude interobservateurs.

PURPOSE: This work evaluated the interobserver variability in cone beam computed tomography (CBCT) registration for prostate cancers treated with intensity-modulated radiotherapy. MATERIAL AND METHODS: Twelve technologists realized 286 CBCT/CT registrations (bone registration followed by prostate to prostate registration). The registration results were compared to those obtained by two radiation oncologists (reference). Each technologist reported the shifts calculated by the software in all three axes. A statistical analysis allowed us to calculate the minimum threshold under which 95% of the observers found similar values. A variance analysis followed by the post hoc test were used to find differences in interobserver registration variability and determine whether any individual users performed registrations which differed significantly from those of the other users. RESULTS: The registration differences compared to the reference in the three directions in terms of 95th percentile are: 2.1mm left-right, 3.5mm target-gun, 7.3mm anterior-posterior. In the posterior direction, 4% of the observers have found differences superior to 8mm, margin used in routine without the use of a daily CBCT. The variance test revealed a P-value <0.05 only for target-gun and for all observers there was no significant difference compared to the reference. CONCLUSION: This study confirmed the interest of a 3D tissue registration for prostate treatments. The registration study showed a good interobserver reproducibility. This showed the importance of a daily CBCT/CT registration in prostate treatment with the possibility of a planning target volume margin reduction in the three directions. An evaluation of a partial delegation of registration to technologists should be done by the radiation oncologists.

[Radiotherapy of cerebral metastases. 196 cases treated from 1973 to 1981]. / La radiothérapie des métastases cérébrales. 196 cas traités de 1973 à 1981.

One hundred and ninety six patients underwent brain irradiation for metastases between 1973 and 1981. Complete follow-up was possible in 180 cases. CT appeared to be the best diagnostic tool. Whatever the type of the tumor, irradiation improved symptoms and signs in 65.3 p. 100 of cases and neurological status in 37 p. 100 of cases. The median survival was 4.2 months, the mean survival 6.6 months, the percent survival at 1 year 11 p. 100. It is necessary to irradiate the whole brain with doses of 40-45 Gy in 4.5 weeks. Shorter periods of irradiation allows a short inhospital stay but implies anti-oedematous treatment. Chemotherapy did not improve the results. Excision surgery had limited indications: isolated metastases, accessible site in zones with no functional importance, good performance status, local control obtained for primary tumor, no extra-cerebral metastases. Surgery must be followed by whole brain irradiation. Derivation is necessary when increased intracranial pressure and treatment resistance are present. Irradiation indications are large. The results were palliative but valuable: irradiation was always indicated except when disorders of consciousness were present. Tolerance was usually good.