The Role of the Dental Surgeon in Controlling the Dissemination of COVID-19: A Literature Review.

As early as December 2019 in the province of Hubei, China, contamination of patients with pneumonia of an unknown etiology occurred. These patients presented with symptoms such as coughing, sore throat, malaise, diarrhea, high fever, and dyspnea. This emerging disease was named COVID-19 due to being part of the group of coronaviruses (CoVs) belonging to the subfamily Orthocoronavirinae, in the Coronaviridae family and in the Nidovirales order. COVID-19 is most commonly transmitted through speech, coughing, sneezing, and salivary sputum. Because dental professionals work closely with the oral cavity, it is imperative that infection prevention controls are strictly adhered to. It is important that the dental profession treats patients while also limiting the possible contamination through the production of aerosol in the dental environment. Furthermore, the dental professional also has a key role in raising awareness and guidance amongst the population concerning COVID-19 related biosafety measures. This literature review aims to inform dental professionals about the COVID-19 pandemic and to present the implications of the virus to the dentist. Dental professionals are considered to be at high risk for contracting SARS-CoV-2.

Effectiveness and Safety of Reirradiation With Stereotactic Ablative Radiotherapy of Lung Cancer After a First Course of Thoracic Radiation: A Meta-analysis.

OBJECTIVE: The effectiveness and safety of reirradiation with stereotactic ablative radiotherapy (re-SABR) in patients with recurrence after a previous course of radiation are limited to small series. We carried out a meta-analysis to summarize existing data and identify trends in overall survival (OS), local control (LC), and toxicity after re-SABR in patients with recurrence of lung cancer. MATERIALS AND METHODS: Eligible studies were identified on Medline, Embase, the Cochrane Library, and the proceedings of annual meetings through June 2019. We followed the PRISMA and MOOSE guidelines. A meta-regression analysis was carried out to assess whether there is a relationship between moderator variables and outcomes. A P-value<0.05 was considered significant. RESULTS: Twenty observational studies with a total of 595 patients treated were included. The 2-year OS and LC were 0.54 (95% confidence interval [CI]: 0.48-0.61) and 0.73 (95% CI: 0.66-0.80), respectively. The rate of any toxicity grade ≥3 was 0.098 (95% CI: 0.06-13.6), with 9 grade 5 toxicity (1.5%). In the meta-regression, the re-SABR dose (P=0.028), tumor size (P=0.031), and time to recurrence (P=0.018) showed an association with survival. For LC, the re-SABR dose (P=0.034) and tumor size (P=0.040) were statistically significant. Any toxicity grade ≥3 showed a relationship with the cumulative dose (P=0.024). Cumulative dose ≤145 versus >145 Gy2 had 3% versus 15% (P=0.013) of any grade ≥3 toxicity. CONCLUSIONS: Re-SABR produces satisfactory LC and OS rates with an acceptable rate of toxicity. The balancing between the re-SABR dose and the tumor location has the potential to reduce severe and fatal toxicity.

Stereotactic Body Radiotherapy for Oligometastatic Prostate Cancer Recurrence: A Meta-analysis.

PURPOSE: The purpose of this study was to evaluate the treatment efficacy of stereotactic body radiotherapy (SBRT) in oligometastatic prostate cancer recurrence and to assess whether there is any relationship between biologically effective dose (BED) and local control (LC). MATERIALS AND METHODS: Eligible studies were identified on Medline, Embase, and the Cochrane Library, and the proceedings of annual meetings through May 2019 were also identified. A meta-regression analysis was performed to assess whether there is a relationship between BED and LC. In the univariate analysis, studies were separated by the study design, the number of metastatic sites, the site of metastases, radiotherapy machine, and prostate-specific antigen level at the time of SBRT. A P-value <0.05 was considered significant. RESULTS: Twenty-three observational studies with a total of 1441 lesions treated were included in the meta-analysis. The proportional rate of LC, progression-free survival, and androgen deprivation-free survival was 0.976 (95% confidence interval [CI]: 0.96-0.98), 0.413 (95% CI: 0.378-0.477), and 20.1 months (95% CI: 14.5-25.6), respectively. In the meta-regression, a linear relationship between BED and LC was detected (P=0.017). Stratifying the BED into 3 levels (BED<100 Gy3, BED 100 to 130 Gy3, and BED>130 Gy3), a significant difference was observed between BED<100 Gy3 (LC=88%) versus BED>100 Gy3 (LC=96%). The rate of any acute and late grade ≥2 toxicity was 1.3% and 1.2%, respectively. CONCLUSIONS: The LC rate with SBRT was excellent with minimal severe acute/late toxicity. Our data suggest a dose relationship between BED and LC, with BED >100 Gy3 resulting in better rates of LC.