Centre François Baclesse

Radiation-induced optic neuropathy (RION) is a rare but serious complication of radiotherapy, leading to progressive vision loss. The temporal dynamics of RION are poorly understood, limiting effective monitoring and intervention. We developed a predictive mixed-effects model of visual field deterioration, a sensitive surrogate marker for clinically-reported RION, by integrating longitudinal clinical and dosimetric data, to anticipate long-term visual outcomes.

Out of a prospective database of 238 patients, 179 eyes from 105 patients treated with pencil beam scanning proton therapy were included. All selected eyes had no significant visual field deficit at baseline, defined as a mean visual sensitivity loss better than -6 dB. Baseline clinical characteristics, detailed dosimetric data, and longitudinal visual field assessments were collected. Temporal changes in mean visual sensitivity were analyzed using feature selection through random forest models and linear regression. A nonlinear mixed-effects model was then developed to predict the trajectory of visual field deterioration over time.

Visual field deterioration progressed significantly over time, with a quadratic model best capturing the kinetics. Mean sensitivity loss accelerated with increasing age and clinical target volume. Incorporating the full dose-volume histogram, the volume of the optic chiasma received at least 40 Gy (V₄₀/chiasma), improved model performance. Simulation based on this model showed that the probability of RION increased sharply over time: 4.6 % at 2 years, and 28.3 % at 5 years.

This model confirms and expands upon prior work by showing that clinical factors can outweigh dosimetric ones in predicting RION progression. Our model was capable of predicting long-term visual outcomes even in patients with limited follow-up.

The Received Signal Strength Indicator (RSSI) measures downlink signal intensity received by smartphones in 4^th Generation LTE networks.

This study evaluated how individual, technical, and spatial factors influenced LTE-RSSI during daily activities.

Between November 2022 and October 2023, adults in France used the XMobiSensePlus Android smartphone application to record RSSI and GPS data. Distance to the operator's nearest antenna, obtained from Cartoradio, population and antenna density and urbanicity were analyzed using a geographic information system. Determinants of RSSI were assessed using an autoregressive mixed model incorporating restricted cubic splines for distance. Environmental exposures were estimated at 1800 MHz using conversion factors.

From 1,969,913 records of 187 participants, with measurements taken every 30 s over 7.9 days, the average LTE-RSSI was -79.3 dBm. The estimated electric field strength was 0.12 V/m, albeit with large uncertainty. The median distance to the nearest antenna was 536 m. Proximity to antennas increased RSSI. Antenna density positively influenced RSSI (overall β = +0.37 dBm per additional antenna per km²). Lower RSSI was observed in the evening and night, particularly in urban areas. Smartphone's technical parameters (Android version and System-on-a-Chip) influenced RSSI, operators did not. Proximity to antennas had greater impact in rural areas.

Urbanicity, distance to the nearest 4G antenna, antenna density, time of day, and smartphone's technical parameters influenced RSSI levels in 4G networks in France, but not operator.

The current survey was conducted among head and neck cancer physicians across the globe to understand the patterns of care and practice for de-novo oligo-metastatic (OM) and oligo-recurrent (OR) head and neck cancer (HNC).

An 18-item survey questionnaire was designed and distributed through the member organizations of the Young Investigator Subcommittee of the HNCIG. The responses were presented as a proportion of the total response for a particular survey item.

A total of 204 responses were obtained with an overall response rate of 15.6 % (204/1307). The incidence of OM disease was reported to be < 10 % by 81.9 % of respondents with a higher incidence of oligo-recurrent disease (up to 20 %). Performance status and extent of disease are absolute essential factors for decision-making. In suitable patients, the majority of respondents (67.4 %) would like to treat with a combination of systemic and local therapy both to primary and metastatic site. For oligo-recurrent HNC, 63.7 % of respondents would treat with both systemic and metastatic directed therapy (MDT) with 27 % would consider MDT alone. Surgery and stereotactic body radiotherapy (SBRT) remain the choice of MDT for lung and liver metastasis. The majority of the respondents use SBRT in > 50 % of their patients.

The current approach to de-novo OM and oligo-recurrent HNC varies in this global survey, but a significant proportion of respondents support radical intent treatment in select cases. Multicentre retrospective and prospective studies as well as international consensus statement are essential prerequisites for developing future clinical guidelines.