The Monte Carlo N-Particle (MCNP) is often used to calculate the radiation dose during computed tomography (CT) scans. However, the physical calculation process of the model is complicated, the input file structure of the program is complex, and the three-dimensional (3D) display of the geometric model is not supported, so that the researchers cannot establish an accurate CT radiation system model, which affects the accuracy of the dose calculation results. Aiming at these two problems, this study designed a software that visualized CT modeling and automatically generated input files. In terms of model calculation, the theoretical basis was based on the integration of CT modeling improvement schemes of major researchers. For 3D model visualization, LabVIEW was used as the new development platform, constructive solid geometry (CSG) was used as the algorithm principle, and the introduction of editing of MCNP input files was used to visualize CT geometry modeling. Compared with a CT model established by a recent study, the root mean square error between the results simulated by this visual CT modeling software and the actual measurement was smaller. In conclusion, the proposed CT visualization modeling software can not only help researchers to obtain an accurate CT radiation system model, but also provide a new research idea for the geometric modeling visualization method of MCNP.
Objective
To explore the incidence and severity of symptoms of the lung cancer patients undergoing concurrent chemoradiation therapy, and reveal the influence of symptom clusters on the patients’ daily activities.
Method
From December 2016 to June 2017, a total of 150 patients with lung cancer who underwent concurrent chemoradiation therapy were investigated by using M. D. Anderson Symptom Inventory of Chinese Version and the revised lung cancer module.
Results
For the patients during the period of concurrent chemoradiation therapy, the symptoms with severity score >5 were fatigue, nausea, poor appetite, cough, distress, disturbed sleep, vomiting, expectoration, and grief; the symptoms with incidence >80% were fatigue, nausea, disturbed sleep, poor appetite, grief, and cough. Joy of life (87.33%), emotion (74.38%), and work (72.67%) were the top three in terms of high incidence of symptom distress. Exploratry factor analysis revealed 4 major symptom clusters, which were fatigue-related symptom cluster, gastrointestinal symptom cluster, emotion symptom cluster, and respiratory symptom cluster.
Conclusions
During the period of concurrent chemoradiation therapy, lung cancer patients suffer from multiple symptom clusters. Medical staff should assess symptoms timely, and provide effective interventions, to improve the patients’ quality of life.
ObjectiveTo systematically summarize recent advancements in the application of artificial intelligence (AI) in key components of radiotherapy (RT), explore the integration of technical innovations with clinical practice, and identify current limitations in real-world implementation. MethodsA comprehensive analysis of representative studies from recent years was conducted, focusing on the technical implementation and clinical effectiveness of AI in image reconstruction, automatic delineation of target volumes and organs at risk, intelligent treatment planning, and prediction of RT-related toxicities. Particular attention was given to deep learning models, multimodal data integration, and their roles in enhancing decision-making processes. ResultsAI-based low-dose image enhancement techniques had significantly improved image quality. Automated segmentation methods had increased the efficiency and consistency of contouring. Both knowledge-driven and data-driven planning systems had addressed the limitations of traditional experience-dependent approaches, contributing to higher quality and reproducibility in treatment plans. Additionally, toxicity prediction models that incorporated multimodal data enabled more accurate, personalized risk assessment, supporting safer and more effective individualized RT. ConclusionsRT is a fundamental modality in cancer treatment. However, achieving precise tumor ablation while minimizing damage to surrounding healthy tissues remains a significant challenge. AI has demonstrated considerable value across multiple technical stages of RT, enhancing precision, efficiency, and personalization. Nevertheless, challenges such as limited model generalizability, lack of data standardization, and insufficient clinical validation persist. Future work should emphasize the alignment of algorithmic development with clinical demands to facilitate the standardized, reliable, and practical application of AI in RT.
Radiation proctopathy, which can be categorized as acute and chronic, is defined as the radiation damage to the rectum caused by radiation therapy in patients with pelvic malignancies. Chronic radiation proctopathy can cause complications such as rectal bleeding, which severely affects patients’ quality of life. At present, endoscopic therapy has become the primary method for diagnosis and treatment of bleeding from chronic radiation proctopathy. In October 2019, the American Society for Gastrointestinal Endoscopy (ASGE) published "ASGE guideline on the role of endoscopy for bleeding from chronic radiation". The guideline described the effectiveness and safety of different endoscopic therapies such as argon plasma coagulation, bipolar electrocoagulation, heater probe, radiofrequency ablation, cryoablation, etc. in the treatment of bleeding from chronic radiation. This paper interprets it to provide references for clinicians in the treatment of bleeding from chronic radiation.
Objective To investigate the clinical factors and dosimetric parameters associated with grade≥2 radiation pneumonitis (RP) after thoracic radiotherapy in patients with locally advanced non-small cell lung cancer (NSCLC). Methods The clinical factors and dosimetric parameters in patients with locally advanced NSCLC who received thoracic radiotherapy at West China Hospital of Sichuan University between January 2016 and January 2018 were retrospectively analyzed. The potential factors associated with the occurrence of grade≥2 RP were analyzed with logistic regression analysis. Results A total of 104 patients were included, and the incidence rate of grade≥2 RP was 19.2%. Multivariate logistic regression analysis showed that the percentage of the heart volume that received more than 20 Gy (V20) [odds ratio (OR)=1.068, 95% confidence interval (CI) (1.004, 1.137), P=0.036], lung mean dose (Dmean) [OR=1.003, 95%CI (1.000, 1.006), P=0.031] and superior vena cava Dmean [OR=1.001, 95%CI (1.000, 1.001), P=0.041] were associated with grade≥2 RP. Receiver operating characteristic (ROC) curve analysis showed that the area under the ROC curve combined with heart V20, lung Dmean and superior vena cava Dmean to predict grade≥2 RP was 0.839 [95%CI (0.752, 0.926)]. In addition, the optimal critical values for heart V20, lung Dmean and superior vena cava Dmean to predict grade≥2 RP were 20%, 13 Gy and 38 Gy, respectively. Conclusions Heart V20, lung Dmean and superior vena cava Dmean are associated with grade≥2 RP after thoracic radiotherapy in patients with locally advanced NSCLC. In addition, taking heart V20<20%, lung Dmean<13 Gy and superior vena cava Dmean<38 Gy as normal organ dose limits may reduce the risk of grade≥2 RP after thoracic radiotherapy for locally advanced NSCLC patients.
Objective To analyze the stabil ity and cl inical outcomes of arthroscopic anterior cruciate l igament (ACL) reconstruction with γ irradiated patellar tendon allograft compared with autograft. Methods From January 2004 to October 2007, 69 patients undergoing arthroscopic ACL reconstruction were prospectively randomized consecutively into two groups: group A (autograft, n=36) and group B (γ irradiated allograft, n=33). In group A, there were 30 males and 6 females with an average age of 30.1 years, including 30 cases of simple ACL rupture and 6 cases of ACL rupture with medial accessory l igament injury; ACL rupture was caused by sports in 28 cases, by traffic accident in 5 cases, and by others in 3 cases; and the time from injury to operation was 1.4 months on average. In group B, there were 26 males and 7 femaleswith an average age of 32.5 years, including 27 cases of simple ACL rupture and 6 cases of ACL rupture with medial accessory l igament injury; ACL rupture was caused by sports in 27 cases, by traffic accident in 4 cases, and by others in 2 cases; and the time from injury to operation was 1.5 months on average. There were no significant differences in general data between two groups (P gt; 0.05). The same arthroscopic technique was used in all ACL reconstructions done by the same surgeon. The cl inical outcome was evaluated and compared by general conditions, pivot shift test, Lachman test, KT-2000 arthrometer testing, Daniel’s one-leg hop test, International Knee Documental Committee (IKDC) scoring, Lysholm knee scoring scale, and Tegner activity score. Results All patients were followed up for 39.5 months (group A) and 37.6 months (group B). In group A, patella fracture occurred in 1 case and anterior knee pain in 2 cases postoperatively. No compl ication occurred in group B. The hospital ization times in groups A and B were (15.6 ± 2.4) days and (15.5 ± 1.5) days, respectively, showing no significant difference (P gt; 0.05). The operation time of group A was longer than that of group B and the fever time of group A was shorter than that of group B, showing significant differences (P lt; 0.05). At the final follow-up, there were significant differences (P lt; 0.05) in Lachman test and the pivot shift test between two groups, between pre- and post-operation; there were no significant differences (P gt; 0.05) in Daniel’s one-leg hop test, the IKDC, Lysholm, and Tegner activity scores between two groups, however, there was a decreased trend in the functional and activity levels in group B. And there was significant difference between pre- and post-operation (P lt; 0.05). At the final follow-up, the differences between normal side and affected side were (2.4 ± 0.6) mm in group A and (5.5 ± 3.6) mm in group B, showing significant difference (P lt; 0.05). There was significant difference in tibial advancement between pre- and post-operation (P lt; 0.05). Conclusion The functional and activity level of the knee after ACL reconstruction with autograft and γ irradiated patellar tendon allograft were similar, but anterior and rotational stabil ity of the involved knee decreases significantly in the group with γ irradiated patellar tendon allograft.
ObjectiveTo compare the static intensity-modulated radiation therapy (IMRT) plans using different beams sets and segments number, and find the better static IMRT plan sets on beams and segments in gastric surgical adjuvant radiotherapy.MethodsFifteen patients who underwent adjuvant radiotherapy for gastric cancer between February 1st and August 30th, 2013 were chosen as subjects through random sampling. Based on the 5 beams static IMRT plans already used in clinical practice, four different static IMRT plans used diverse beams sets for each patient were designed in the same treatment planning system (Pinnacle 9.2). The beams sets of static IMRT plans were as follows: 7 coplanar equal beams; 5 coplanar equal beams; 4 coplanar beams of 310, 20, 90 and 180°; 3 coplanar beams of 310, 65 and 180°. Sufficient segments 65 was set as the max segments number in order to compare the plans’ difference just resulting from beams. In the second step, the max segments number was changed from 65 to 45 and 25 to design two different static IMRT plans for the 4 coplanar beams static IMRT plans. The dosimetric parameters were compared for the planning target volume (PTV) and organs at risk (OARs). The monitor units and treatment times of the different static IMRT plans were also evaluated.ResultsWhen the max segments number was set to 65, the 4 coplanar beams static IMRT plans were a little better on PTV conformability than the 5 coplanar beams static IMRT plans used in clinical practice (0.74±0.04 vs. 0.73±0.05, P<0.01). Meanwhile, better OARs dose sparing especially for liver and kidneys were gained by the 4 coplanar beams static IMRT plans, for example, the percent volume gained 30 Gy for liver [(22.71±6.10)%vs. (24.03±6.84)%, P<0.01] and the percent volume gained 20 Gy for the right kidney [(14.97±6.72)%vs. (19.41±6.14)%, P<0.01]. The PTV conformability of the 4 coplanar beams static IMRT plans reduced as the max segments number became smaller (0.74±0.04vs. 0.73±0.04 vs. 0.71±0.04, P<0.05). However, they were still acceptable in clinical practice. And the better dose sparing for liver and kidneys were retained. The average reductions of 1.8 and 4.3 minutes on the irradiation time were get by the 4 coplanar beams static IMRT plans with the max segments number 45 and 25 compared to that with the max segments number 65 [(494.66±26.79)vs. (384.26±14.99) vs. (235.00±9.21) s, P<0.01]. And the raises of treatment efficiency were 22.3% and 52.4%, respectively (P<0.05).ConclusionsThe 4 coplanar beams static IMRT plans with fewer segments could ensure plan quality, and protect the OARs better in the meanwhile, especially for liver and kidneys. The treatment time is reduced as well. The 4 coplanar beams static IMRT plans could improve the treatment efficiency.
In order to decrease the radiotherapy error caused by target motion, an adaptive radiation therapy system for target movement compensation has been designed and passed by simulation test. The real-time position of the target labelled by a mark was captured by the control system and compared with the reference point. Then the treatment couch was controlled to move in the opposite direction for compensation according to that position information. The three dimensional movement of the treatment bed relied on three independent stepping motors which were controlled by a control system. Experiments showed that the adaptive radiation therapy system was able to reduce the therapy error caused by target movement. It would be useful in radiotherapy clinical practice with high real-time position precision.
ObjectiveTo summarize clinical application progress of stereotactic radiotherapy for primary hepatocellular carcinoma.
MethodsThe literatures about the research progress of the stereotactic radiotherapy for primary hepatocellular carcinoma were reviewed.
ResultsRadiotherapy for hepatocellular carcinoma is importantly based on the radiation biology of the liver and the radiophysics of the liver cancer. Stereotactic precision radiotherapy is an effective and low toxic treatment for early hepatocellular carcinoma, moreover, it alone or in combination with microwave ablation, hepatic artery chemoembolization for unresectable hepatocellular carcinoma is safe and effective method for the treatment.
ConclusionsThe optimal dose model for hepatocellular carcinoma, hepatocellular carcinoma radical dose level are problems that need further exploration, and radiobiology, radiation physics research must be strengthened to explore it, stereotactic precision radiotherapy treatment modalities in the treatment of hepatocellular carcinoma position will become increasingly people attention.
Objective
To evaluate the effects of neoadjuvant long-course chemoradiotherapy (CRT), neoadjuvant short-course radiotherapy (SCRT), and total neoadjuvant treatment (TNT) on chemoradiotherapy related complications and perioperative safety in mid-low rectal cancer patients.
Methods
The clinical data of 63 rectal cancer patients who received neoadjuvant (chemo) radiotherapies and surgery treatment in West China Hospital from Jul. 2014 to Feb. 2016 were retrospectively analyzed. According to the neoadjuvant regimen, the patients were divided into CRT group (n=15), SCRT group (n=30), and TNT group (n=18), and then the effects of these 3 kinds of neoadjuvant regimen on chemoradiotherapy related complications and perioperative safety were compared.
Results
① Chemoradiotherapy related complications: among all the included 63 patients, 29 patients (46.0%) occurred chemoradiotherapy related complications, including radiation enteritis in 9 patients and bone marrow suppression in 25 patients. There were significant differences in the overall incidence of chemoradiotherapy related complications, incidence of radiation enteritis and bone marrow suppression (P≤0.001). The overall incidence of chemoradiotherapy related complications and incidence of bone marrow suppression of SCRT group were lower. ② Perioperative safety: no significant differences were found in the incidence of surgical complications, incidence of specific surgical complication, operation duration, intraoperative blood loss, and postoperative flatus time (P<0.05), but there was significant difference in the postoperative hospital stay among 3 groups (P=0.033), the postoperative hospital stay of SCRT group was shorter.
Conclusion
CRT, SCRT, and TNT have similar effect on the safety in the mid-low rectal cancer patients, which suggests that SCRT is worthy of further research and promotion.
