BackgroundSevere complications, such as eye damage and dysfunciton of salivary glands, have been reported after radiotherapy among patients with head and neck cancer. Complications such as visual impairment have also been reported after proton therapy with pencil beam scanning (PBS). In the case of PBS, collimation can sharpen the penumbra towards surrounding normal tissue in the low energy region of the proton beam. In the current study, we examined how much the dose to the normal tissue was reduced by when intensity-modulated proton therapy (IMPT) was performed using a multi-leaf collimator (MLC) for patients with maxillary sinus cancer.MethodsComputed tomography findings of 26 consecutive patients who received photon therapy at Okayama University Hospital were used in this study. We compared D2% of the region of interest (ROI; ROI-D2%) and the mean dose of ROI (ROI-mean) with and without the use of an MLC. The organs at risk (OARs) were the posterior retina, lacrimal gland, eyeball, and parotid gland. IMPT was performed for all patients. The spot size was approximately 5–6 mm at the isocenter. The collimator margin was calculated by enlarging the maximum outline of the target from the beam’s eye view and setting the margin to 6 mm. All plans were optimized with the same parameters.ResultsThe mean of ROI-D2% for the ipsilateral optic nerve was significantly reduced by 0.48 Gy, and the mean of ROI-mean for the ipsilateral optic nerve was significantly reduced by 1.04 Gy. The mean of ROI-mean to the optic chiasm was significantly reduced by 0.70 Gy. The dose to most OARs and the planning at risk volumes were also reduced.ConclusionsCompared with the plan involving IMPT without an MLC, in the dose plan involving IMPT using an MLC for maxillary sinus cancer, the dose to the optic nerve and optic chiasm were significantly reduced, as measured by the ROI-D2% and the ROI-mean. These findings demonstrate that the use of an MLC during IMPT for maxillary sinus cancer may be useful for preserving vision and preventing complications.
Background Stereotactic body radiation therapy (SBRT) is an established therapy for medically inoperable early-stage non-small cell lung cancer (NSCLC). Many elderly patients are medically inoperable owing to comorbidities. Therefore, SBRT may be a useful therapy for elderly patients. However, the application of SBRT for patients aged ≥ 80 years has not been completely elucidated. Therefore, this study aimed to assess the clinical utility of SBRT for elderly patients aged ≥ 80 years with pathologically proven early-stage NSCLC. Methods We retrospectively evaluated the data of patients aged ≥ 80 years with pathologically proven primary NSCLC who underwent SBRT at our institution between January 2009 and March 2020. Treatment outcomes and toxicities were analyzed. We used the Kaplan–Meier method to estimate survival curves and the log-rank test to compare the survival curves. We performed univariate and multivariate Cox regression analyses. p-values < 0.05 were regarded significant. Results Sixty-four patients (65 lesions) were included, and the median follow-up period was 38.7 (range 3.5–95.7) months. The median age was 82.9 (range 80.0–94.8) years. Sixteen patients were medically operable, and 48 patients were medically inoperable. The prescribed dose of SBRT was either 48 Gy in four fractions or 60 Gy in 10 fractions. The median survival time was 60.0 months (95% confidence interval, 43.5–71.1). The 1-, 3-, and 5-year local control, cancer-specific survival, progression-free survival, and overall survival rates were 98.4%, 98.4%, 81.0%, and 88.9%; 90.1%, 93.7%, 58.9%, and 68.3%; and 87.4%, 83.5%, 38.2%, and 47.5%, respectively. Multivariate analysis revealed that inoperability and solid nodules were the predictors of poor overall survival after SBRT in elderly patients. Two patients (3.1%) had grade 3 radiation pneumonitis, and one patient (1.6%) had grade 5 radiation pneumonitis. Conclusions SBRT was feasible in patients aged ≥ 80 years with NSCLC. It achieved good local control with minimal toxicity. SBRT may be beneficial in elderly patients with early-stage NSCLC.
We intended to investigate whether muscle and adipose masses were associated with prognosis among patients with stage III non-small-cell lung cancer (NSCLC) who were undergoing chemoradiotherapy (CCRT). We retrospectively explored data of patients with stage III NSCLC who underwent definitive CCRT (≥ 60 Gy) between January 2004 and March 2018 at our hospital. We examined the relationship of overall survival (OS) with body mass index (BMI), skeletal muscle index (SMI), psoas muscle index (PMI), visceral adipose tissue index (VAI), subcutaneous adipose tissue index (SAI), and visceral-to-subcutaneous adipose tissue area ratio (VSR) using log-rank tests for the univariate analysis and Cox proportional hazard models for the multivariate analysis. Overall, 16, 32, and 12 patients had stage IIIA, IIIB, and IIIC NSCLC, respectively. The total radiotherapy dose ranged from 60 Gy/30 fractions to 66 Gy/33 fractions. In the univariate analysis, the performance status (PS), BMI, and SMI were associated with OS, whereas the PMI, VAI, SAI, and VSR were not. In the multivariate analysis, the PS and SMI were associated with OS. The hazard ratios and 95% confidence intervals were 2.91 and 1.28–6.64 for PS, and 2.36 and 1.15–4.85 for SMI, respectively. The 1, 3, and 5-year OS rates were 92.1%, 59.6%, and 51.0% in patients with high SMI, and 63.6%, 53.8%, and 17.9% in patients with low SMI, respectively. The SMI correlated with prognosis in our study population, whereas adipose mass did not. Therefore, sarcopenia should be considered while predicting the OS in such patients.
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