Objective:To explore the feasibility and advantages of applying visualized thermosensitive color-changing bolus in postmastectomy radiotherapy (PMRT) for breast cancer.Methods:Forty patients with breast cancer treated with PMRT in the Second Affiliated Hospital of Soochow University from June 2023 to June 2024 were prospectively selected. They were randomly divided into test and control groups (also referred to as groups A and B, respectively), with 20 patients in each group. Group A, underwent two CT scans: the first scan without bolus (image A1) and the second scan with visualized thermosensitive color-changing bolus (image A2). They were treated with visualized thermosensitive color-changing bolus. Group B also underwent two CT scans: the first scan without bolus (image B1) and the second scan with conventional commercial bolus (image B2), and then were treated with conventional commercial bolus. In the radiotherapy planning, images A1 and A2 were designed as A1-Plan and A2-Plan, and A3-Plan was created by transferring the A1-Plan onto image A2. Images B1 and B2 were designed as B1-Plan and B2-Plan, and B3-Plan was created by transferring the B1-Plan onto image B2. The radiation fields and target optimization functions were identical. The dosimetric differences and skin toxicity reactions between different plans were compared.Results:In Group A, A1-Plan and A2-Plan manifested no statistically significant differences ( P > 0.05) in the doses to organs at risk (OARs), including the ipsilateral lung ( V5 Gy, V10 Gy, V20 Gy), heart ( Dmean), contralateral breast ( Dmean), and skin ( Dmax and Dmean), target homogeneity index (HI), conformity index (CI), prescription dose volume ( V50 Gy), depth of maximum dose ( Dmax), and monitor unit (MU). In Group B, B3-Plan compared to B1-Plan showed reduced V50 Gy (89.9% vs. 95%), HI (0.153 vs. 0.136), and CI (0.817 vs. 0.810), while the two plans displayed no statistically significant differences in doses to OARs. In contrast, A3-Plan and B3-Plan exhibited statistically significant differences ( t = 2.78, 2.29, -0.47, 0.51, 3.13, P < 0.05) in V50 Gy (94.05% vs. 89.90%), Dmax (5 665.4 cGy vs. 5 632.7 cGy), HI (0.148 vs. 0.163), CI (0.83 vs. 0.82), and skin Dmean (5 153.6 cGy vs. 5 048.2 cGy). Compared to the conventional commercial bolus of the same thickness, the visualized thermosensitive color-changing bolus yielded a significantly reduced air cavity volume (3 833 mm 3vs. 21 498 mm 3,t = -9.65, P < 0.05). Both groups experienced only grade I skin toxicity reactions. Conclusions:Compared to the conventional commercial bolus of the same thickness, the visualized thermosensitive color-changing bolus shows a more effective dosimetric distribution in terms of target coverage, HI, and CI, a higher fit to the skin, highly visualized air cavity, and higher positional repeatability in fractionated radiotherapy, demonstrating high practicality and safety.

Objective:To analyze and predict the incidence and mortality rate condition from 1990 to 2021 and 2022 to 2045 in China so as to evaluate the impact of different ages, periods, and birth cohorts on liver cancer.Methods:The 2021 Global Burden of Disease Study database was used. The variation trend of standardized incidence and mortality of liver cancer was analyzed using the Joinpoint regression model. The age, period, and cohort effects were used to explore liver cancer incidence and mortality rates based on the age-period-cohort model. The Nordpred prediction model was used to fit the trend of standardized incidence and mortality rates in liver cancer. Simultaneously, the standardized incidence and mortality rates were predicted from 2022 to 2045 for liver cancer. Joinpoint regression analysis was performed using the GBDASR_aapc package.Results:The standardized incidence and mortality rate from 1990 to 2021 of liver cancer showed an overall downward trend year by year in China ( P<0.01). Age, period, and cohort effects were all risk factors for the incidence of liver cancer. The incidence and mortality rates both increase with age, reaching a peak in the 85～89 age group. The risk of HCC morbidity and mortality was higher in the population of early-stage birth cohorts. Although the period effect showed a slight upward trend over time, the change in the period effect was relatively small. The incidence and mortality rates after the age of 40 were significantly higher in males than those of females. The prediction results showed that the standardized incidence and mortality rates from 2022 to 2045 of liver cancer have had a downward trend in China. Conclusion:The standardized incidence and mortality rates of liver cancer show an overall downward trend in China, but the burden in males is still high. Therefore, liver cancer prevention and control work in the future should continue to strengthen intervention in high-risk groups.

Objective:To explore the feasibility and advantages of applying visualized thermosensitive color-changing bolus in postmastectomy radiotherapy (PMRT) for breast cancer.Methods:Forty patients with breast cancer treated with PMRT in the Second Affiliated Hospital of Soochow University from June 2023 to June 2024 were prospectively selected. They were randomly divided into test and control groups (also referred to as groups A and B, respectively), with 20 patients in each group. Group A, underwent two CT scans: the first scan without bolus (image A1) and the second scan with visualized thermosensitive color-changing bolus (image A2). They were treated with visualized thermosensitive color-changing bolus. Group B also underwent two CT scans: the first scan without bolus (image B1) and the second scan with conventional commercial bolus (image B2), and then were treated with conventional commercial bolus. In the radiotherapy planning, images A1 and A2 were designed as A1-Plan and A2-Plan, and A3-Plan was created by transferring the A1-Plan onto image A2. Images B1 and B2 were designed as B1-Plan and B2-Plan, and B3-Plan was created by transferring the B1-Plan onto image B2. The radiation fields and target optimization functions were identical. The dosimetric differences and skin toxicity reactions between different plans were compared.Results:In Group A, A1-Plan and A2-Plan manifested no statistically significant differences ( P > 0.05) in the doses to organs at risk (OARs), including the ipsilateral lung ( V5 Gy, V10 Gy, V20 Gy), heart ( Dmean), contralateral breast ( Dmean), and skin ( Dmax and Dmean), target homogeneity index (HI), conformity index (CI), prescription dose volume ( V50 Gy), depth of maximum dose ( Dmax), and monitor unit (MU). In Group B, B3-Plan compared to B1-Plan showed reduced V50 Gy (89.9% vs. 95%), HI (0.153 vs. 0.136), and CI (0.817 vs. 0.810), while the two plans displayed no statistically significant differences in doses to OARs. In contrast, A3-Plan and B3-Plan exhibited statistically significant differences ( t = 2.78, 2.29, -0.47, 0.51, 3.13, P < 0.05) in V50 Gy (94.05% vs. 89.90%), Dmax (5 665.4 cGy vs. 5 632.7 cGy), HI (0.148 vs. 0.163), CI (0.83 vs. 0.82), and skin Dmean (5 153.6 cGy vs. 5 048.2 cGy). Compared to the conventional commercial bolus of the same thickness, the visualized thermosensitive color-changing bolus yielded a significantly reduced air cavity volume (3 833 mm 3vs. 21 498 mm 3,t = -9.65, P < 0.05). Both groups experienced only grade I skin toxicity reactions. Conclusions:Compared to the conventional commercial bolus of the same thickness, the visualized thermosensitive color-changing bolus shows a more effective dosimetric distribution in terms of target coverage, HI, and CI, a higher fit to the skin, highly visualized air cavity, and higher positional repeatability in fractionated radiotherapy, demonstrating high practicality and safety.

Objective:To analyze and predict the incidence and mortality rate condition from 1990 to 2021 and 2022 to 2045 in China so as to evaluate the impact of different ages, periods, and birth cohorts on liver cancer.Methods:The 2021 Global Burden of Disease Study database was used. The variation trend of standardized incidence and mortality of liver cancer was analyzed using the Joinpoint regression model. The age, period, and cohort effects were used to explore liver cancer incidence and mortality rates based on the age-period-cohort model. The Nordpred prediction model was used to fit the trend of standardized incidence and mortality rates in liver cancer. Simultaneously, the standardized incidence and mortality rates were predicted from 2022 to 2045 for liver cancer. Joinpoint regression analysis was performed using the GBDASR_aapc package.Results:The standardized incidence and mortality rate from 1990 to 2021 of liver cancer showed an overall downward trend year by year in China ( P<0.01). Age, period, and cohort effects were all risk factors for the incidence of liver cancer. The incidence and mortality rates both increase with age, reaching a peak in the 85～89 age group. The risk of HCC morbidity and mortality was higher in the population of early-stage birth cohorts. Although the period effect showed a slight upward trend over time, the change in the period effect was relatively small. The incidence and mortality rates after the age of 40 were significantly higher in males than those of females. The prediction results showed that the standardized incidence and mortality rates from 2022 to 2045 of liver cancer have had a downward trend in China. Conclusion:The standardized incidence and mortality rates of liver cancer show an overall downward trend in China, but the burden in males is still high. Therefore, liver cancer prevention and control work in the future should continue to strengthen intervention in high-risk groups.

Objective:To evaluate the dose calculation accuracy of cone-beam CT (CBCT) image by actual measurement method.Methods:CBCT images of 60 patients in the Second Affiliated Hospital of Soochow University from September, 2021 to May, 2022 were retrospectively analyzed. CBCT images of full-fan and half-fan scanning of the head, half-fan scanning of the chest and pelvis were obtained by the Varian OBI system. Hounsfield unit - electron density (HU-ED) curves corresponding to the scanning conditions were established with CIRS electron density phantom. The radiotherapy plans were designed on the CBCT images, and the dose calculation results of the detection point were compared with the ionization chamber measurement results to analyze the dose error. Then, three-dimensional dose verification system was adopted to detect the accuracy of the CBCT image radiotherapy plans implementation process in 60 patients, and the accuracy of dose calculation was verified according to the D 99%, D mean, D 1% of target volume, D mean and D 1% of organs at risk (OAR), and the γ pass rate. Results:In point dose detection in phantom, the dose calculation errors of CBCT images in the above four scanning patterns were -1.06%±0.87%、-1.67%±0.86%, 0.91%±0.73%, -1.54%±0.90%, respectively. In dosimetric verification based on patients' CBCT image treatment plan, the mean difference of D mean, D 99%, and D 1% of planning target volume (PTV) in all scanning modes were not higher than 2%, and the D mean and D 1% differences of other OAR were not higher than 3%, except for the lens of patients in the head. The average γ values of target volume and OAR were less than 0.5 under the criteria of 3%/2 mm. Conclusions:Under the condition of correctly establishing HU-ED curves, intensity-modulated radiation therapy (IMRT) / volumetric-modulated arc therapy (VMAT) planning based on CBCT images can be employed to estimate and monitor the actual dose to target volume and OAR in adaptive radiotherapy. Full-fan scanning patterns can further improve the accuracy of dose calculation for the head of patients.

Objective:To reconstruct the three-dimensional (3D) dose distribution in radiotherapy based on the convolutional neural networks (CNN) through multi-perspective scintillation light processing.Methods:First, fluorescence images were captured from three orthogonal perspectives using a complementary metal-oxide-semiconductor (CMOS) imaging sensor. Then, the images were converted into 3D images, which were input to the trained CNN for dose reconstruction. Finally, the reconstructed doses in different fields were evaluated in terms of gamma pass rate, mean-square error (MSE), percentage depth dose (PDD), and cross beam profile (CBP). Additionally, as the CNN model, 3D-Unet was pre-trained on a virtual dataset.Results:With the 50% maximum dose of as the threshold and 3%/3 mm as the standard, the central-plane and stereo-mean gamma pass rates of all field reconstruction distributions were over 90%, with MSEs remained below 1%. Besides, the PDD and CBP curves showed MSEs below 1‰ and below 1%, respectively.Conclusions:The deep learning-based method for 3D dose reconstruction using scintillation light contributes to enhanced verification of instantaneous 3D relative dose based on plastic scintillation detectors.

In recent years, the development of bispecific antibodies (bsAbs) has been rapid, with many new structures and target combinations being created. The boom in bsAbs has led to the successive issuance of industry guidance for their development in the US and China. However, there is a high degree of similarity in target selection, which could affect the development of diversity in bsAbs. This review presents a classification of various bsAbs for cancer therapy based on structure and target selection and examines the advantages of bsAbs over monoclonal antibodies (mAbs). Through database research, we have identified the preferences of available bsAbs combinations, suggesting rational target selection options and warning of potential wastage of medical resources. We have also compared the US and Chinese guidelines for bsAbs in order to provide a reference for their development.

Objective:To understand the normative status of physical dose description in domestic radiobiology studies through literature study.Methods:According to the scoring system recommended by the National Cancer Institute (NCI) and Desrosiers et al, evaluate (full Score: 10 points) the normalization of physical dosimetry description in the radiobiology-related articles published in two important journals, Chinese Journal of Radiation Oncology and Chinese Journal of Radiological Medicine and Protection, in past 5 years.Results:A total of 222 relevant articles from these two journals were included, and a median score of 5.0 was evaluated. Among them, 72.1% of the literatures scored 4.0-7.0 points, 68.0% of the literatures scored ≤5.5 points, and 18.5% scored ≤3.0 points. 90.1% and 97.7% of the literatures described " the type of ray" and " absorbed dose" , with the highest average score (0.90 and 0.98 points) respectively. The lowest average score of " dosimetry calibration" was 0 point.Conclusions:Although the most of literatures described " the type of ray" and " absorbed dose" , most other details of dosimetric parameters were not reported. Therefore, there is a deficiency in the standardized description of physical dosimetry in domestic radiobiology literatures, which may affect the reproducibility and interpretability of research result.

Objective:To explore the method of improving the accuracy of dose calculation of treatment plan in radiotherapy for patients with metal implants.Methods:A CT simulator with metal artifact reduction technique (MAR) was utilized to scan the CIRS intensity-modulated phantom with metal rods and 8 patients with steel nails implanted in the centrum for radiotherapy. Radiotherapy plans were designed using conventional CT images, MAR images and density-filled images. The dose calculation errors between single field and intensity-modulated radiotherapy (IMRT) plan were compared. The effect of mental implants and their artifacts on the irradiation dose of IMRT plan was evaluated.Results:In the conventional CT images of the phantom, when the incident path of the field failed to pass through the metal region, the dose calculation error for a single field was 3.85%, and the range of dose error for the field was 4.46%-74.11% when passing through the metal region. IMRT planning errors might exceed the clinically acceptable range when the incident path of the field passed through the metal region, and the errors tended to increase with the increase of dose weight of this field. After processing the images with density filling and artifact reduction techniques, the errors of the single field were 1.23% and 0.89%-4.73%, respectively, and the dose error of IMRT was 1.84%. The error of IMRT plan was 1.88% if density filling technique alone was employed to process the metal region. Due to the influence of metal implants and their artifacts, the minimum dose, average dose and prescription dose coverage actually received in the tumor target area were lower than IMRT plan results based on conventional CT images. The dosimetric difference of organs at risk was not statistically significant.Conclusions:In the radiotherapy plan based on conventional CT images, there may be a large dose calculation error when the incident path of field passes through the metal region. If the metal material is known, density filling of the metal region in the planning system can effectively improve the accuracy of dose calculation. Metal artifact reduction technique can significantly improve the image quality and further reduce dose calculation error, which should be a routine technique for CT machines equipped with this function to perform simulated localization of patients with metal implants.

Objective: To evaluate and predict the pelvic dose by analyzing two pelvic contour definitions and identify the influencing factors of the pelvic dose in postoperative IMRT for cervical cancer, aiming to provide reference for postoperative pelvis-sparing IMRT for cervical cancer. Methods: Sixty cervical cancer patients receiving postoperative IMRT with unrestricted pelvic dose were selected. Two sets of pelvic contours (pelvic anatomy and pelvic Mell) were delineated as per the anatomical and Mell methods. The dose relationship between two methods was analyzed after redesigning the treatment plan by limiting dose of pelvic anatomy. The correlation analysis was performed by Pearson’s correlation method. The factors affecting the pelvic anatomy dose were identified by Logistic multivariate regression analysis and a dose prediction model was subsequently established. Results: The volumes of pelvic anatomy and pelvic Mell were 925.82 cm³ and 1141.20 cm³(P=0.000). There was a significant correlation between them (r>0.622, P=0.000). The dose of pelvic anatomy was significantly higher than that of pelvic Mell. The relationship of V₁₀, V₂₀ and V₃₀ between them was y=-8+ 1.01x, y=-13+ 1.05x and y=-4+ 0.9x, respectively. The dose limits of pelvic Mell recommended by literatures(V₁₀<90%, V₂₀<75%, V₃₀<60%) were translated into V₁₀<97%, V₂₀<83% and V₃₀<70%, respectively. The pelvic anatomy dose was significantly reduced after dose limiting. The V₁₀, V₂₀, V₃₀ and D_mean were significantly decreased by 3.64%, 12.69%, 12.02% and 6.93%(P=0.000, 0.000, 0.000), respectively. Multivariate analysis showed that the overlapping volume of pelvic anatomy within PTV was an independent influencing factor of pelvic anatomy dose (P<0.05). Patients with a relative overlapping volume of less than 18% could easily meet the dose limiting requirement. Conclusions Both two pelvic contour definitions can be applied in postoperative pelvis-sparing IMRT for cervical cancer. Use of pelvic dose limiting can significantly reduce the IMRT dose. The overlapping volume of the pelvis within PTV is an independent influencing factor of pelvic dose. Patients whose overlapping volume within the PTV relative to pelvis is less than 18% can easily meet the dose limiting requirement.