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BackgroundThe coronavirus disease 2019 (COVID-19) pandemic has caused extreme challenges for the healthcare system. Medical masks have been proven to effectively block disease transmission. Radiotherapeutic departments are at unique risk for disease exposure with the repeated daily treatment schedule. A protocol of mask wearing during daily treatment was established, and the effect of wearing medical masks on dosimetry during proton beam therapy (PBT) was validated.MethodsA department protocol of medical mask wearing was initiated after the COVID-19 pandemic. Medical masks that were made under standardized specification and regulation were obtained for analyses. The physical and dosimetric characteristics of these medical masks were measured by different proton energies using commercialized measurement tools.ResultsPatients and staff were able to adopt the protocol on a weekly basis, and no adverse events were reported. The average physical thickness of a single piece of medical mask was 0.5 mm with a water equivalent thickness (WET) of 0.1 mm.ConclusionOur study revealed that mask wearing for patients undergoing daily radiotherapy is feasible and can provide basic protection for patients and staff. The impact of mask wearing on dosimetry was only 0.1 mm in WET, which has no impact on clinical PBT treatment. A medical mask-wearing policy can be applied safely without dosimetric concerns and should be considered as a standard practice for PBT centers during the COVID-19 pandemic.

The identification of early distant metastases (DM) in patients with newly diagnosed, previously untreated nasopharyngeal carcinoma (NPC) plays an important role in selecting the most appropriate treatment approach. Here, we sought to investigate the predictive value of distinct MRI parameters for the detection of early DM.Between November 2010 and June 2011, a total of 51 newly diagnosed NPC patients were included. All of the study participants were followed until December 2014 at a single institution after completion of therapy. DM was defined as early when they were detected on pretreatment FDG-PET scans or within 6 months after initial diagnosis. The following parameters were tested for their ability to predict early DM: pretreatment FDG-PET standardized uptake value (SUV), MRI-derived AJCC tumor staging, tumor volume, and dynamic contrast-enhanced (DCE) values. The DCE-derived ve was defined as the volume fraction of the extravascular, extracellular space.Compared with patients without early DM, patients with early DM had higher SUV, tumor volume, DCE mean (median) ve, ve skewness, ve kurtosis, and the largest mean ve selected among sequential slices (P

The Pencil Beam Scanning (PBS) technique in modern particle therapy offers a highly conformal dose distribution but poses challenges due to the interplay effect, an interaction between respiration-induced organ movement and PBS. This study evaluates the effectiveness of different volumetric rescanning strategies in mitigating this effect in liver cancer proton therapy. We used a Geant4-based Monte Carlo simulation toolkit, 'TOPAS,' and an image registration toolbox, 'Elastix,' to calculate 4D dose distributions from 5 patients' four-dimensional computed tomography (4DCT). We analyzed the homogeneity index (HI) value of the Clinical Tumor Volume (CTV) at different rescan numbers and treatment times. Our results indicate that dose homogeneity stabilizes at a low point after a week of treatment, implying that both rescanning and fractionation treatments help mitigate the interplay effect. Notably, an increase in the number of rescans doesn't significantly reduce the mean dose to normal tissue but effectively prevents high localized doses to tissue adjacent to the CTV. Rescanning techniques, based on statistical averaging, require no extra equipment or patient cooperation, making them widely accessible. However, the number of rescans, tumor location, diaphragm movement, and treatment fractionation significantly influence their effectiveness. Therefore, deciding the number of rescans should involve considering the number of beams, treatment fraction size, and total delivery time to avoid unnecessary treatment extension without significant clinical benefits. The results showed that 2–3 rescans are more clinically suitable for liver cancer patients undergoing proton therapy. [ABSTRACT FROM AUTHOR]

Head and neck cancer (HNC) patients who are unable to return to work after completing treatment might face financial loss and reduced self-esteem. The aim of this study was to identify factors influencing a return to work in HNC cancer patients in the first 6 months after treatment. This cross-sectional study examined HNC patients who completed treatment from the outpatient radiation department of a single cancer center in northern Taiwan. Patients were assessed according to psychological distress, patient-perceived health status, barriers to returning to work, and facilitators of returning to work. Of the 106 HNC patients surveyed, 54.7% successfully returned to work. Barriers to returning to work included poor self-perception of health, greater psychological distress, and age ≥50 years. Patients who had higher psychological distress, returned to work after start of the pandemic, or received reconstruction surgery were less likely to experience a positive environment facilitating a return to work. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is a major cause of cancer death in Taiwan, and in the past 30–40 years, Taiwan has been committed to its prevention and treatment. We aimed to investigate the secular trends of characteristics and the survival of HCC in recent decades after making increased efforts. Between 2011 and 2019, a total of 73,817 cases were enrolled from the TCR database. The overall male-to-female ratio was 7/3. The overall, male and female mean ages increased from 63.8 to 66.1 years, 62.0 to 64.3 years and 68.3 to 70.4 years, respectively. After dividing by viral etiologies and gender, the mean age showed increasing trends in all subgroups. The proportions of HBV-HCC, HCV-HCC, HBV+HCV-HCC and Non-HBV+non-HCV-HCC were 48.3%, 25.2%, 5.3% and 21.3% in males, compared with 25.5%, 48.6%, 5.3% and 20.5% in females, respectively. The 5-year survival rates of BCLC stages 0, A, B, C and D were 70%, 58%, 34%, 11% and 4%, respectively. The proportion of BCLC stage 0 increased from 6.2% to 11.3%. Multivariate analysis showed that being female, older age, diagnostic year, BCLC stages, hospital level, body mass index, smoking, alcohol consumption, AFP, Child–Pugh classification and HBV/HCV status were independent predictors for survival. In recent decades, the overall survival of HCC in Taiwan has been improving and might be partly associated with increased BCLC 0 and Child–Pugh A patients, while with the consequent age of patients increasing over time. The proportion of viral-related HCC is decreasing, while nonviral-related HCC is increasing. [ABSTRACT FROM AUTHOR]