Impact of the COVID-19 Pandemic on Head and Neck Cancer Management: The Experience of the Maxillo-Facial Surgery Department of a French Regional Referral Center in a High-Incidence Area.

Background: Cancer patients are at a high risk of complications in cases of infection, and head and neck cancers (HNC) are no exception. Since late 2019, SARS-CoV-2 has caused a global health crisis, with high rates and severe forms of the disease in cancer patients. Hospitalization, surgery and radiotherapy were rapidly described as increasing the risk of infection. Since March 2020, the Amiens University Hospital (France) has been taking care of COVID-19 patients while its maxillofacial surgery department managed HNC patients without interruption, even during lockdown periods. However, many questions concerning the impact on patient care were still pending. The aim of this study is to describe HNC management in our center during the first epidemic peak and to evaluate the impact of containment measures on patient treatment. Methods: We retrospectively included 44 HNC patients treated in our department between 1 March and 31 August 2020. Two groups were defined according to the period of care: lockdown (March to May) and lighter restrictions (June to August). Results: The results show typical epidemiological characteristics, maintained management times and non-downgraded procedures. Conclusions: Thus, during the first epidemic peak, continuity of care and patients' safety could be ensured thanks to adequate means, adapted procedures and an experienced surgical team.

Evaluation of a Granular Bone Substitute for Bone Regeneration Using an Optimized In Vivo Alveolar Cleft Model.

Alveolar cleft is a common congenital deformity that requires surgical intervention, notably using autologous bone grafts in young children. Bone substitutes, in combination with mesenchymal stem cells (MSCs), have shown promise in the repair of these defects. This study aimed to evaluate the regenerative capabilities of a granular bone substitute using an optimized alveolar cleft model. Thirty-six rats underwent a surgical procedure for the creation of a defect filled with a fragment of silicone. After 5 weeks, the silicone was removed and the biomaterial, with or without Wharton's jelly MSCs, was put into the defect, except for the control group. The rats underwent µCT scans immediately and after 4 and 8 weeks. Analyses showed a statistically significant improvement in bone regeneration in the two treatment groups compared with control at weeks 4 and 8, both for bone volume (94.64% ± 10.71% and 91.33% ± 13.30%, vs. 76.09% ± 7.99%) and mineral density (96.13% ± 24.19% and 93.01% ± 27.04%, vs. 51.64% ± 16.51%), but without having fully healed. This study validates our optimized alveolar cleft model in rats, but further work is needed to allow for the use of this granular bone substitute in the treatment of bone defects.