Dosimetry and efficiency comparison of knowledge-based and manual planning using volumetric modulated arc therapy for craniospinal irradiation.

BACKGROUND: Craniospinal irradiation (CSI) poses a challenge to treatment planning due to the large target, field junction, and multiple organs at risk (OARs) involved. The aim of this study was to evaluate the performance of knowledge-based planning (KBP) in CSI by comparing original manual plans (MP), KBP RapidPlan initial plans (RPI), and KBP RapidPlan final plans (RPF), which received further re-optimization to meet the dose constraints. PATIENTS AND METHODS: Dose distributions in the target were evaluated in terms of coverage, mean dose, conformity index (CI), and homogeneity index (HI). The dosimetric results of OARs, planning time, and monitor unit (MU) were evaluated. RESULTS: All MP and RPF plans met the plan goals, and 89.36% of RPI plans met the plan goals. The Wilcoxon tests showed comparable target coverage, CI, and HI for the MP and RPF groups; however, worst plan quality was demonstrated in the RPI plans than in MP and RPF. For the OARs, RPF and RPI groups had better dosimetric results than the MP group (P < 0.05 for optic nerves, eyes, parotid glands, and heart). The planning time was significantly reduced by the KBP from an average of 677.80 min in MP to 227.66 min (P < 0.05) and 307.76 min (P < 0.05) in RPI, and RPF, respectively. MU was not significantly different between these three groups. CONCLUSIONS: The KBP can significantly reduce planning time in CSI. Manual re-optimization after the initial KBP is recommended to enhance the plan quality.

Integrating subvolume dose and myocardial perfusion imaging parameters to assess the impact of radiation therapy on heart function in breast cancer patients: A comparative analysis between left- and right-sided breast cancer.

BACKGROUND: This study aimed to utilize an innovative method of integrating the 20 subvolume dose of left ventricle and the Tl-201 single photon emission computed tomography (SPECT) with myocardial perfusion imaging (MPI) parameters in patients with left- and right-sided breast cancer after radiation therapy. METHODS: Female patients with breast cancer underwent SPECT MPI before commencing radiotherapy and 12 months later were enrolled from January 2014 to December 2018. The images of CT simulation and SPECT MPI were integrated into the treatment planning system. The differences of doses and parameters of MPI in all cardiac subvolumes between left- and right-sided breast cancer patients were analyzed. RESULTS: Patients with left-sided breast cancer (n = 61) received a higher radiation dose to the heart, left ventricular, and its territories and subvolumes, compared to patients with right-sided breast cancer (n = 19). The 20-segment analysis also showed statistically significant disparities in the average radiation doses received by the two groups. In different coronary artery territories, the end-diastolic perfusion and end-systolic perfusion showed a decrease in both sides, with no significant differences. However, the wall motion and wall thickening showed a significant decline in subregions within the left- and right-sided coronary artery territories. CONCLUSION: This study demonstrates an innovative integrated method combining the left ventricular 20 regional doses with SPECT MPI which shows that left-sided breast cancer patients receive a higher subvolume dose than right-sided breast cancer patients. Further research is needed to confirm the potential impact on heart function after radiotherapy on both sides.

Hazard-based risk grouping effectively stratifying breast cancer patients in post-irradiation long-term heart diseases: a population-based cohort study.

Background: Even though advanced radiotherapy techniques provide a better protective effect on surrounding normal tissues, the late sequelae from radiation exposure to the heart are still considerable in breast cancer patients. The present population-based study explored the role of cox-regression-based hazard risk grouping and intended to stratify patients with post-irradiation long-term heart diseases. Materials and methods: The present study investigated the Taiwan National Health Insurance (TNHI) database. From 2000 to 2017, we identified 158,798 breast cancer patients. Using a propensity score match of 1:1, we included 21,123 patients in each left and right breast irradiation cohort. Heart diseases, including heart failure (HF), ischemic heart disease (IHD), and other heart diseases (OHD), and anticancer agents, including epirubicin, doxorubicin, and trastuzumab, were included for analysis. Results: Patients received left breast irradiation demonstrated increased risks on IHD (aHR, 1.16; 95% CI, 1.06-1.26; p < 0.01) and OHD (aHR, 1.08; 95% CI, 1.01-1.15; p < 0.05), but not HF (aHR, 1.11; 95% CI, 0.96-1.28; p = 0.14), when compared with patients received right breast irradiation. In patients who received left breast irradiation dose of >6,040 cGy, subsequent epirubicin might have a trend to increase the risk of heart failure (aHR, 1.53; 95% CI, 0.98-2.39; p = 0.058), while doxorubicin (aHR, 0.59; 95% CI, 0.26-1.32; p = 0.19) and trastuzumab (aHR, 0.93; 95% CI, 0.33-2.62; p = 0.89) did not. Older age was the highest independent risk factor for post-irradiation long-term heart diseases. Conclusion: Generally, systemic anticancer agents are safe in conjunction with radiotherapy for managing post-operative breast cancer patients. Hazard-based risk grouping may help stratify breast cancer patients associated with post-irradiation long-term heart diseases. Notably, radiotherapy should be performed cautiously for elderly left breast cancer patients who received epirubicin. Limited irradiation dose to the heart should be critically considered. Regular monitoring of potential signs of heart failure may be conducted.

Integrating 18 F-FDG PET/CT with lung dose-volume for assessing lung inflammatory changes after arc-based radiotherapy for esophageal cancer: A pilot study.

OBJECTIVE: The incidence of radiation pneumonitis (RP) has a highly linear relationship with low-dose lung volume. We previously established a volume-based algorithm (VBA) method to improve low-dose lung volume in radiotherapy (RT). This study assessed lung inflammatory changes by integrating fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18 F-FDG PET/CT) with VBA for esophageal cancer patients undergoing arc-based RT. METHODS: Thirty esophageal cancer patients received 18 F-FDG PET/CT imaging pre-RT and post-RT were included in a retrospective pilot study. We fused lung doses and parameters of PET/CT in RT planning. Based on VBA, we used the 5Gy isodose curve to define high-dose (HD) and low-dose (LD) regions in the lung volume. We divided patients into non-RP (nRP) and RP groups. The maximum, mean standardized uptake value (SUVmax, SUVmean), global lung glycolysis (GLG), mean lung dose (MLD) and V5-30 in lungs were analyzed. Area under the curve values were utilized to identify optimal cut-off values for RP. RESULTS: Eleven patients in the nRP group and 19 patients in the RP group were identified. In 30 RP lungs, post-RT SUVmax, SUVmean and GLG of HD regions showed significant increases compared to values for pre-RT lungs. There were no significant differences in values of 22 nRP lungs. Post-RT SUVmax and SUVmean of HD regions, MLD, and lung V5 and V10 in RP lungs were significantly higher than in nRP lungs. For detecting RP, the optimal cut-off values were post-RT SUVmax > 2.28 and lung V5  > 47.14%. CONCLUSION: This study successfully integrated 18 F-FDG PET/CT with VBA to assess RP in esophageal cancer patients undergoing RT. Post-RT SUVmax > 2.28 and lung V5  > 47.14% might be potential indicators of RP.

Planning evaluation of a novel volume-based algorithm for personalized optimization of lung dose in VMAT for esophageal cancer.

Radiotherapy treatment planning (RTP) is time-consuming and labor-intensive since medical physicists must devise treatment plans carefully to reduce damage to tissues and organs for patients. Previously, we proposed the volume-based algorithm (VBA) method, providing optimal partial arcs (OPA) angle to achieve the low-dose volume of lungs in dynamic arc radiotherapy. This study aimed to implement the VBA for esophageal cancer (EC) patients and compare the lung dose and delivery time between full arcs (FA) without using VBA and OPA angle using VBA in volumetric modulated arc therapy (VMAT) plans. We retrospectively included 30 patients diagnosed with EC. RTP of each patient was replanned to 4 VMAT plans, including FA plans without (FA-C) and with (FA + C) dose constraints of OARs and OPA plans without (OPA-C) and with (OPA + C) dose constraints of OARs. The prescribed dose was 45 Gy. The OARs included the lungs, heart, and spinal cord. The dose distribution, dose-volume histogram, monitor units (MUs), delivery time, and gamma passing rates were analyzed. The results showed that the lung V5 and V10 in OPA + C plans were significantly lower than in FA + C plans (p < 0.05). No significant differences were noted in planning target volume (PTV) coverage, lung V15, lung V20, mean lung dose, heart V30, heart V40, mean heart dose, and maximal spinal cord dose between FA + C and OPA + C plans. The delivery time was significantly longer in FA + C plans than in OPA + C plans (237 vs. 192 s, p < 0.05). There were no significant differences between FA + C and OPA + C plans in gamma passing rates. We successfully applied the OPA angle based on the VBA to clinical EC patients and simplified the arc angle selection in RTP. The VBA could provide a personalized OPA angle for each patient and effectively reduce lung V5, V10, and delivery time in VMAT.

Enhancing clinical effectiveness of pre-radiotherapy workflow by using multidisciplinary-cooperating e-control and e-alerts: A SQUIRE-compliant quality-improving study.

Radiotherapy (RT) is useful in managing cancer diseases. In clinical practice, early initiation of RT is crucial for enhancing tumor control. But, delivering precise RT requires a series of pre-RT working processes in a tight staff-cooperation manner. In this regard, using information system to conduct e-control and e-alerts has been suggested to improve practice effectiveness; however, this effect is not well defined in a real-world RT setting.We designed an information system to perform e-control and e-alerts for the whole process of pre-RT workflow to shorten processing time, to improve overall staff satisfaction, and to enhance working confidence.A quality-improving study conducted in a large RT center.Externally validated data were retrospectively analyzed for comparison before (from Sep. 2012 to Dec. 2012, n = 223) and after (from Sep. 2013 to Dec. 2013, n = 240) implementation of pre-RT e-control and e-alerts.Applying the e-control with delay-working e-alerts in pre-RT workflow was the main intervention.Nine workstations were identified in pre-RT workflow. The primary outcome measure was the processing time in each pre-RT workstations before and after implementing the e-control and e-alerts. Secondary measures were staff-working confidence and near-missing cases during the process of pre-RT workflow.After implementing e-control, overall processing time of pre-RT workflow was shortened from 12.2 days to 8.9 days (P < .001). Follow-up data (till Jul. 2016) showed a durable effect of 9.2 days, being still below the predefined threshold of <10 days.Using a multidisciplinary-cooperating information system is useful to conduct e-control and e-alerts in the whole process of pre-RT workflow. Clinical effectiveness, staff satisfaction, and working confidence are able to be enhanced obviously.

Implementing web-based ping-pong-type e-communication to enhance staff satisfaction, multidisciplinary cooperation, and clinical effectiveness: A SQUIRE-compliant quality-improving study.

BACKGROUND: Frequent multidisciplinary communication is essential in conducting daily radiotherapy (RT) practice. However, traditional oral or paper-based communication has limitations. E-communication has been suggested, but its effects are still not well demarcated in the field of radiation oncology. OBJECTS: In our web-based integrated information platform, we constructed a ping-pong-type e-communication function to transfer specific notations among multidisciplinary RT staffs. The purpose was to test whether applying this e-communication can increase effectiveness of multidisciplinary cooperation when compared with oral or paper-based practice. Staff satisfaction and clinical benefits were also demonstrated. DESIGN AND SETTING: A real-world quality-improving study was conducted in a large center of radiation oncology. PARTICIPANTS AND DATASET USED: Before and after applying multidisciplinary e-communication (from 2014 to 2015), clinical RT staffs were surveyed for their user experience and satisfaction (n = 23). For measuring clinical effectiveness, a secondary database of irradiated head and neck cancer patients was re-analyzed for comparing RT toxicities (n = 402). INTERVENTIONS: Applying ping-pong-type multidisciplinary reflective e-communication was the main intervention. OUTCOME MEASURES: For measuring staff satisfaction, eight domains were surveyed, such as timeliness, convenience, and completeness. For measuring clinical effectiveness of multidisciplinary cooperation, event rates of severe (i.e., grade 3-4) RT mucositis and dermatitis were recorded. RESULTS: Overall, when compared with oral communication only, e-communication demonstrated multiple benefits, particularly on notation-review convenience (2.00 ±â€Š1.76 vs 9.19 ±â€Š0.81; P < 0.0001).When compared with paper-based practice, e-communication showed statistically significant benefits on all eight domains, especially on notation-review convenience (5.05 ±â€Š2.11 vs 9.19 ±â€Š0.81; P < 0.0001) and convenience of feedback notation (4.81 ±â€Š1.72 vs 8.76 ±â€Š1.09; P < 0.0001).Moreover, staff satisfaction was gradually increased from oral (3.57 ±â€Š1.94), paper-based (5.57 ±â€Š2.06), to e-communication (8.76 ±â€Š0.70; P < 0.0001). Secondary measurement confirmed these observations.Before and after facilitating multidisciplinary cooperation by using e-communication, severe (i.e., grade 3-4) mucositis and dermatitis were decreased from 21.7% to 10% then to 5.1%. CONCLUSIONS: Replacing oral or paper-based practice with e-communication is useful in facilitating RT multidisciplinary teamwork. Staff satisfaction and clinical effectiveness can be increased.

Significant symptoms alleviation and tumor volume reduction after combined simultaneously integrated inner-escalated boost and volumetric-modulated arc radiotherapy in a patient with unresectable bulky hepatocellular carcinoma: A care-compliant case report.

BACKGROUND: Clinically, elderly patients with unresectable bulky hepatocellular carcinoma (HCC) are difficult to manage, especially in those with co-infections of hepatitis B and C virus. Herein, we reported such a case treated with radiotherapy (RT) by using combined simultaneously integrated inner-escalated boost and volumetric-modulated arc radiotherapy (SIEB-VMAT). After RT, significant symptoms alleviation and durable tumor control were observed. CASE SUMMARY: At presentation, an 85-year-old male patient complained abdominal distention/pain, poor appetite, and swelling over bilateral lower limbs for 1 month. On physical examination, a jaundice pattern was noted. Laboratory studies showed impaired liver and renal function. Abdominal computed tomography (CT) revealed a 12.5-cm bulky tumor over the caudate lobe of the liver. Biopsy was done, and hepatocellular carcinoma (HCC) was reported histopathologically. As a result, AJCC stage IIIA (cT3aN0M0) and BCLC stage C were classified. Surgery, radiofrequency ablation (RFA), trans-catheter arterial chemoembolization (TACE), and sorafenib were not recommended because of his old age, central bulky tumor, and a bleeding tendency. Thus, RT with SIEB-VMAT technique was given alternatively. RT was delivered in 26 fractions, with dose gradience as follows: 39 Gy on the outer Plan Target Volume (PTV), 52 Gy in the middle PTV, and 57.2 Gy in the inner PTV. Unexpectedly, cyproheptadine (a newly recognized potential anti-HCC agent) was retrospectively found to be prescribed for alleviating skin itching and allergic rhinitis since the last 2 weeks of the RT course (2 mg by mouth Q12h for 24 months).After RT, significant symptoms alleviation and tumor volume reduction were observed for 32 months till multiple bone metastases. Before and after RT, a large tumor volume reduction rate of 88.7% was observed (from 608.4 c.c. to 68.7 c.c.). No severe treatment toxicity was noted during and after RT. The patient died due to aspiration pneumonia with septic shock at 4 months after bone metastases identified. CONCLUSIONS: SIEB-VMAT physically demonstrated double benefits of intratumor dose escalation and extra-tumor dose attenuation. Significant tumor regression and symptoms alleviation were observed in this elderly patient with unresectable bulky HCC. Further prospective randomized trials are encouraged to demarcate effective size of SIEB-VMAT with or without cyproheptadine.

Leukemia Risk After Cardiac Fluoroscopic Interventions Stratified by Procedure Number, Exposure Latent Time, and Sex: A Nationwide Population-Based Case-Control Study.

A number of cardiac fluoroscopic interventions have increased rapidly worldwide over the past decade. Percutaneous transluminal coronary angioplasty (PTCA) and stent implantation have become increasingly popular, and these advancements have allowed patients to receive repetitive treatments for restenosis. However, these advancements also significantly increase radiation exposure that may lead to higher cumulative doses of radiation. In the present study, a nationwide population-based case-controlled study was used to explore the risk of leukemia after cardiac angiographic fluoroscopic intervention.A total of 5026 patients with leukemia and 100,520 control patients matched for age and sex (1:20) by a propensity score method without any cancer history were enrolled using the Registry Data for Catastrophic Illness and the National Health Insurance Research Database (NHIRD) of Taiwan between 2008 and 2010. All subjects were retrospectively surveyed (from year 2000) to determine receipt of cardiac fluoroscopic interventions. Data were analyzed using conditional logistic regression models, and estimated crude and adjusted odds ratios (95% confidence interval).After adjusting for age, gender, and comorbidities, PTCA was found to be associated with an increased risk of leukemia with an adjusted OR of 1.566 (95% CI, 1.282-1.912), whereas coronary angiography alone without PTCA and cardiac electrophysiologic study were not. Our results also showed that an increased frequency of PTCA and coronary angiography was associated with a higher risk of leukemia (adjusted OR: 1.326 to 1.530 [all P < 0.05]). Gender subgroup analyses demonstrated that men were associated with a higher risk of leukemia compared with women.These results provide additional data in the quantification of the long-term health effects of radiation exposure derived from the cardiac fluoroscopic diagnostic and therapeutic intervention. PTCA alone or PTCA with coronary angiography was associated with an elevated risk of leukemia. Continued follow-up of existing cohorts will be valuable to help assess lifetime risks of cancer.

National Survey of Radiation Dose and Image Quality in Adult CT Head Scans in Taiwan.

INTRODUCTION: The purpose of the present study was to evaluate the influence of different variables on radiation dose and image quality based on a national database. MATERIALS AND METHODS: Taiwan's Ministry of Health and Welfare requested all radiology departments to complete a questionnaire for each of their CT scanners. Information gathered included all scanning parameters for CT head scans. For the present analysis, CT machines were divided into three subgroups: single slice CT (Group A); multi-detector CT (MDCT) with 2-64 slices (Group B); and MDCT with more than 64 slices (Group C). Correlations between computed tomography dose index (CTDI) and signal-to-noise ratio (SNR) with cumulated tube rotation number (CTW(n)) and cumulated tube rotation time (CTW(s)), and sub group analyses of CTDI and SNR across the three groups were performed. RESULTS: CTDI values demonstrated a weak correlation (r = 0.33) with CTW(n) in Group A. SNR values demonstrated a weak negative correlation (r = -0.46) with CTW(n) in Group C. MDCT with higher slice numbers used more tube potential resulting in higher effective doses. There were both significantly lower CTDI and SNR values in helical mode than in axial mode in Group B, but not Group C. CONCLUSION: CTW(n) and CTW(s) did not influence radiation output. Helical mode is more often used in MDCT and results in both lower CTDI and SNR compared to axial mode in MDCT with less than 64 slices.