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Objective:To analyze the cardiac dosimetry of lymph node irradiation in the internal breast region after left-sided breast cancer surgery and to assess its impact on patients' quality of life.Methods:The clinical data of 108 patients who underwent inverse intensity modulated radiotherapy (IMRT) after left-sided breast cancer surgery in Cancer Hospital of Nantong University from May 2019 to May 2021 were collected and retrospectively analyzed, and divided into a study group (with internal breast, 55 cases) and a control group (without internal breast, 53 cases) according to whether the postoperative radiotherapy included lymph node irradiation in the internal breast region. The dosimetric indexes of planned target area (PTV) , cardiac tolerance, serum myocardial injury markers and quality of life before and after radiotherapy were compared between the two groups.Results:In terms of PTV dosimetry, the conformality index (CI) of the study group and the control group were 0.73±0.07 and 0.75±0.08, the homogeneity index (HI) were 0.17±0.03 and 0.17±0.02, the D max were (55.69±1.02) Gy and (55.46±1.13) Gy, the D mean were (50.54±0.23) Gy and (50.48±0.21) Gy respectively, there were no statistically significant differences ( t=1.38, P=0.169; t<0.01, P>0.999; t=1.11, P=0.269; t=1.41, P=0.160) . In terms of cardiac receptivity, the D mean of the two groups were (5.93 ± 0.32) Gy, (5.64 ± 0.30) Gy, V 40 were (0.47 ± 0.10) %, (0.41 ± 0.11) %, and V 30 were (2.48 ± 0.51) %, (2.06 ± 0.49) % respectively, and there were statistically significant differences ( t=4.86, P<0.001; t=2.97, P=0.004; t=4.36, P<0.001) . The levels of serum troponin Ⅰ (cTnⅠ) before radiotherapy in the study group and the control group were (0.09±0.02) ng/ml and (0.09±0.01) ng/ml, creatine kinase isoenzyme MB (CK-MB) were (0.27±0.08) U/L and (0.25±0.08) U/L, myoglobin (MYo) were (3.84±1.02) μg/L and (3.69±0.97) μg/L, and brain natriuretic peptide (BNP) were (172.35±16.24) pg/ml and (169.81±15.93) pg/ml respectively, there were no statistically significant differences ( t<0.01, P>0.999; t=1.30, P=0.197; t=0.78, P=0.436; t=0.82, P=0.414) . One month after radiotherapy, the levels of serum cTnⅠ in the two groups were (0.09±0.03) ng/ml and (0.09±0.02) ng/ml, CK-MB were (0.29±0.09) U/L and (0.28±0.08) U/L, MYo were (4.06±1.08) μg/L and (4.01±1.03) μg/L, and BNP were (175.13±17.09) pg/ml, (172.47±16.28) pg/ml respectively, there were no statistically significant differences ( t<0.01, P>0.999; t=0.61, P=0.544; t=0.25, P=0.806; t=0.83, P=0.410) . The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) scores before radiotherapy in the study and the control groups were (60.24±5.13) points and (61.19±5.46) points, (74.12±7.20) points and (75.35±7.88) points at 1 month after radiotherapy, (77.53±7.14) points and (78.95±7.08) points at 6 months after radiotherapy, and (75.02±6.93) points and (76.68±6.74) points at 1 year after radiotherapy respectively, there were no statistically significant differences ( t=0.93, P=0.353; t=0.85, P=0.399; t=1.04, P=0.302; t=1.26, P=0.210) . The EORTC QLQ-C30 scores at 1 month, 6 months, and 1 year after radiotherapy were higher than those before radiotherapy in the two groups, and there were statistically significant differences (all P<0.001) . Conclusion:IMRT containing lymph node irradiation in the internal breast region after left breast cancer surgery brings a certain degree of increased cardiac dose, but it is feasible to control it within a certain range and does not affect the patients' cardiac function or quality of life in the short term.
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Objective To compare the size of target volume,amplitudes of movements in different directions,movement vector,dose to the diseased lung,whole lung volume,and setup error between free breathing fixation (method A) and four-dimensional computed tomography (4DCT)-guided abdominal balloon compression fixation (method B),and to demonstrate that the 4DCT-guided abdominal balloon compression fixation is effective in the treatment of non-small cell lung cancer (NSCLC).Methods A retrospective analysis was performed among 80 patients with NSCLC in our hospital.In those patients,40 received method A and 40 method B.The GTVfree and GTVpress were delineated on the maximum intensity projection (MIP) images of 10 respiratory phases using method A and method B,respectively.The PTVfree and PTVPress were obtained by expansion of the GTVfree and GTVpress,respectively.The paired t test was used to analyze the differences in the PTV,maximum amplitudes of movements in three dimensions,absolute value of the movement vector (|V|),and volume between method A and method B.The treatment planning system was used to compare the V5,V10,V20,and V30 of the diseased lung and the whole lung volume between method A and method B.All patients underwent cone-beam CT (CBCT) scans after positioning.Setup error was obtained by matching the CBCT images with the MIP images in the XVI system based on bone and grayscale values.Results The PTVfree and PTVpress were (283.2± 12.74) and (201.8± 12.99)cm3,respectively (P=0.002).The maximum amplitudes of movements in the right-left,superior-inferior,and anterior-posterior directions as well as thel V | value were (0.22±0.02),(1.85±0.08),(0.43±0.26),and (1.91±0.27) em,respectively,for method A,and (0.05±0.01),(0.41±0.03),(0.16±0.16),and (0.44±0.16) cm,respectively,for method B (P=0.120,0.001,0.070).The V5,V10,V20,and V30 for the diseased lung and total lung volume were (61.26± 4.27) ％,(44.52± 1.70) ％,(28.22± 3.13) ％,(18.26±5.17)％,and (3556±223.12) cm3,respectively,for method A,and (52.74±4.78)％,(38.76±4.92) ％,(23.71 ±4.03) ％,(15.54±3.43) ％,and (3376±311.65) cm3,respectively,for method B (P =0.001,0.003,0.004,0.021,0.004).There was no significant difference in setup error obtained by the XVI system between the two fixation methods (P＞0.05).Conclusions Without increasing setup error,abdominal balloon compression can effectively control the lung movement amplitude,reduce the planning target volume,and reduce the radiation dose to the lung in patients with NSCLC.
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Objective To compare the errors of double-center and single-center setup, and to study the role of both on reducing the rotational setup errors for the patients with esophageal carcinoma depend on rigid registration errors between online kV-cone-beam computed tomography (kV-CBCT) images and plans for CT images. Methods 20 patients with middle esophageal carcinoma received image scanning before treatment every week by using double-center setup and CBCT, and single-center setup images of 20 patients were taken from the X volume image (XVI) system. Then the images of both setup types, registration errors of CT image and rotational setup errors were compared respectively. Every patient received kV-CBCT scanning analysis before treatment every week, and 6 times in total. 240 group of kV-CBCT images from all of the patients were off-line matched with plans for CT images to calculate the errors of X-axis, Y-axis, Z-axis. Then the data of linear errors and rotational setup errors from patients were collected, aiming at putting the error data into the patients treatment program and analyzing the significances. Results The standard registration of double-center setup was as follows: T (X) (0.28 ±0.19) cm, T (Y) (0.27 ±0.19) cm, T (Z) (0.33 ±0.12) cm, R (X) (0.40 ±0.19)° , R (Y) (0.30 ±0.18)° , R (Z) (0.30 ±0.19)° . The standard registration of single-center setup was as follows:T(X) (0.32±0.20) cm, T(Y) (0.29±0.25)cm, T(Z) (0.31±0.16) cm, R(X) (2.2±0.68)°, R(Y) (0.5±0.32)°, R(Z) (2.10±0.60)°. There were statistical differences between linear errors in T(X) and rotational setup errors in R(X), R(Y) or R(Z) (P< 0.05). Conclusion Double-center position can reduce the rotational setup errors, especially in X-axis, Y-axis errors, and may provide more help for the radiation oncology departments without on-board CBCT.
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Objective To evaluate the application of improved belly board in postoperative patients of rectal cancer radiotherapy and explore the influence of its set-up repeatability.Methods CBCT was used to measure the intra fractional and inter fractional setup errors using normal or improved belly board respectively.The data was analyzed with statistic method.Results There was no significance of intra fractional setup errors on x-axis (P ＞ 0.05).There was significance on y and z-axis (P ＜ 0.05).There was no significance of interfrational setup errors on x-axis (P ＞ 0.05) and there was significance on y and z-axis (P ＜ 0.05) using normal belly board.There was no significance of intrafractional setup errors on x,y and z-axis (P ＞ 0.05).There was also no significance of interfractional setup errors on x,y and z-axis (P ＞ 0.05) with using improved belly board.Conclusion The method of improved belly board has more advantage than nomal belly board in controlling set-up repeatability,and it is conductive to improve accuracy of patients treatment.
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Objective To investigate influence of laser positioning system to position repeatability of patients treated with radiotherapy for pelvic tumors.Methods Forty patients with pelvic tumors were divided into two groups,using laser positioning system positioning (20 cases) and conventional positioning (20 cases),respectively,CBCT was used to verify and analyze the setup errors of two groups.Results The setup errors on X,Y and Z axes in laser positioning system positioning group were (2.63±1.07) mm,(2.38±1.28) mm and (2.46±1.21) mm,they were (3.04±1.22) mm,(2.55±1.35) mm and (3.09±1.37) mm in conventional positioning group.It has significance reduce on X and Z axes (P =0.040,0.003,respectively) by using laser positioning system,and has no significance on Y axis (P =0.432).Conclusion It can improve patient positioning repeatability effectively by using laser positioning system for patient positioning.
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Objective To evaluate the effect of an equivalent uiform dose optimization (EUD) based optimization algorithm in sparing the organ at risk (OAR) of tumor treated with intensity-modulated radiation therapy (IMRT).Methods 10 patients of nasopharyngeal carcinoma (NPC),10 patients of esophagus cancer,6 patients of rectum cancer were randomly selected from all patients received IMRT treatment.Then physical optimization constraints (dose/dose-volume constraints) were designed as EUD optimization,while the physical objectives for targets and other OAR were unchanged.Results There was statistically significant difference in protecting OAR in 8 NPC patients of PLANED group compared with those of PLANNO_EuD group (t values were 2.590,2.352,3.656,2.148,2.283,3.683,2.192,2.353,2.146,2.276,2.126,P ＜ 0.05).There was no statistically significant difference in protecting OAR in 10 cases of esophageal cancer between PLANEUD group and PLANNO_EUD group (t value were 0.408,0.427,0.920,P ＞ 0.05).There was statistically significant difference in protecting OAR in 6 cases of rectum cancer of PLANED group compared with those of PLANNO_EUD group (t values were 2.332,2.693,2.279,2.244,P ＜ 0.05).Conclusion EUD optimization can reduce the doses to OAR which may be quite helpful to reduce the occurrence rate of OAR complications.