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Objective:To investigate and understand current status of radiotherapy resources in the Association of Southeast Asian Nations (ASEAN) and analyze the radiotherapy needs of ASEAN countries, aiming to provide suggestions for China's radiotherapy technology international assistance work.Methods:We created a database of 10 ASEAN countries using open-source data, including data on population size, per capita gross national income, new cancer cases, and radiotherapy equipment (megavolt units). We also estimated the number of cases requiring radiotherapy and the demand for radiotherapy equipment. Descriptive statistics were used to present aggregate data and national data.Results:In 2020, the number of new cancer cases in ASEAN countries was 1.0992 million, and the estimated total number of cancer patients requiring radiotherapy was 700 300. The number of radiotherapy equipment required was 1 406. At present, the actual number of radiotherapy equipment in ASEAN countries is 564, and there is a certain gap between the existing radiotherapy resources in some ASEAN countries and the actual needs of cancer patients in their own countries. In 2040, the estimated number of new cancer cases in ASEAN countries will be 1.803 million, and the estimated total number of cancer patients who need radiotherapy in ASEAN countries will be 1.141 2 million. The number of required radiotherapy equipment will be 2 287. By 2040, the growth rate of radiation therapy equipment demand in ASEAN countries will be 305%, and all ASEAN countries need to allocate more radiotherapy resources to cope with the increase in the number of cancer patients and radiotherapy demand.Conclusions:ASEAN countries have a huge demand for radiotherapy in the next two decades, while there are significant differences among different countries. China's precision radiotherapy science and technology have huge potential for ASEAN countries. Radiotherapy science and technology international assistance work based on the needs of ASEAN countries will help China's radiotherapy continue to exert influence and promote the health and well-being of people in ASEAN countries.
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Objective:To investigate the advantage of three dimensional(3D)-printed tissue compensators in radiotherapy for superficial tumors at irregular sites.Methods:A subcutaneous xenograft model of prostate cancer in nude mice was established. Mice were randomly divided into no tissue compensator group( n=6), common tissue compensator group( n=6), and 3D-printed tissue compensator group( n=6). Computed tomography (CT) images of nude mice in the 3D-printed tissue compensator group were acquired. Compensator models were made using polylactic acid, and material properties were evaluated by measuring electron density. CT positioning images of the three groups after covering the corresponding tissue compensators were acquired to delineate the gross tumor volume (GTV). Nude mice in the three groups were irradiated with 6 MV X-rays at the prescribed dose. The prescribed dose for the three groups was 1 500 cGy. The dose distribution in the GTV of the three groups was calculated and compared using the analytical anisotropic algorithm in the Eclipse 13.5 treatment planning system. The metal-oxide-semiconductor field-effect transistor was used to verify the actual dose received on the skin surface of nude mice. Results:The air gap in the 3D-printed tissue compensator group and the common tissue compensator group was 0.20±0.07 and 0.37±0.07 cm 3, respectively ( t=4.02, P<0.01). For the no tissue compensator group, common tissue compensator group, and 3D-printed tissue compensator group, the D95% in the target volume was (1 188.58±92.21), (1 369.90±146.23), and (1 440.29±45.78) cGy, respectively ( F=9.49, P<0.01). D98% was (1 080.13±88.30), (1 302.76±158.43), and (1 360.23±48.71) cGy, respectively ( F=11.17, P<0.01). Dmean was (1 549.08±44.22), (1 593.05±65.40), and (1 638.87±40.83) cGy, respectively ( F=4.59, P<0.05). The measured superficial dose was (626.03±26.75), (1 259.83±71.94), and (1 435.30±67.22) cGy, respectively ( F=263.20, P<0.001). The percentage variation in tumor volume growth after radiation was not significantly different between the common tissue compensator group and the 3D-printed tissue compensator group ( P>0.05). Conclusions:3D-printed tissue compensators fit well to the body surface, which reduces air gaps, effectively increases the dose on the body surface near the target volume, and provides ideas for radiotherapy for superficial tumors at some irregular sites.
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Objective:To compare the efficacy and safety of standard treatment with or without adjuvant chemotherapy in patients with highly malignant non-metastatic prostate cancer.Methods:In this prospective non-randomized controlled study, consecutive non-metastatic prostate cancer patients with pathologically proven Gleason score of 9-10 or Gleason score of 5 admitted to Peking University First Hospital were enrolled. Four to six cycles of chemotherapy using docetaxel ± carboplatin regimen were added or not after standard radical therapy. The primary end point was 5-year event-free survival (EFS), and the secondary end points were distant metastasis-free survival (MFS), overall survival (OS), and treatment-related adverse events. The survival curve was drawn by Kaplan-Meier method. The differences between two groups were analyzed by log-rank test.Results:A total of 176 patients were consecutively enrolled from November 2019 to January 2022 of which 138 patients received only standard radical therapy (control group), and 38 patients received adjuvant chemotherapy after standard radical therapy (chemotherapy group). The median follow-up time was 13.4 (2.0-34.0) months. All patients survived. The 30-month EFS rates in the chemotherapy and control groups were 100% and 85.6%, respectively ( P=0.064). There were no events in the chemotherapy group, while there were 12 cases of events in the control group, including 6 cases of biochemical recurrence and 6 cases of imaging progression. The 30-month MFS rates in two groups were 100% and 91.9%, respectively ( P=0.205). After the 1 vs. 2 propensity score matching, the EFS and MFS rates in two groups were 100% vs. 85.7% ( P=0.056), and 100% vs. 92.2% ( P=0.209), respectively. The incidence rates of grade 2 and above urinary toxicity in the chemotherapy and control groups were 2.6% and 7.2% ( P=0.354), respectively. The incidence rates of grade 2 and above rectal toxicity were 5.3% and 5.1% ( P=0.711), respectively. Grade 3 and above chemotherapy-related toxicity in the chemotherapy group were leukopenia (31.6%), thrombocytopenia (2.6%) and alopecia (13.2%). Conclusion:The addition of adjuvant chemotherapy after standard radical therapy tends to improve the overall EFS of patients with highly malignant prostate cancer, and the adverse effects are tolerable, which should be confirmed by long-term follow-up results.
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Objective:To explore the effect of a new teaching mode, which includes bridge-in, outcome, pre-test, participation, post-test and summary (BOPPPS), on the online teaching of radiobiology related knowledge for cancer radiotherapy practitioners.Methods:Taking the cell survival curve, cell cycle and radiosensitivity as examples, the radiotherapy practitioners in multiple university-affiliated hospitals were organized to carry out a multicenter prospective randomized control study. All practitioners were randomly divided into BOPPPS group and control group. The courses for BOPPPS group were designed as an online classroom, consisting of pre-class preparation, online teaching and post-class stages. The online teaching stage included video viewing, basic knowledge learning, literature discussion, group discussion and others. The control group employed the traditional teaching mode. The χ2 test was used to compare the consistency of general conditions between the two groups, and nonparametric test was used to compare the differences in scores between two or more groups. Results:The score of the pre-class test was 58.56 ± 0.99. Post-class average score for BOPPPS group was 85.48±0.85 and for control group 77.79±1.10, with the former being higher 7.69 ( Z=5.31, P<0.001) than the latter. The average answer time was (296.62±15.40) s for BOPPPS group and (386.41±21.27) s for control group, with the former being shorter 89.79 s ( Z=3.34, P=0.001) than latter. Subgroup analysis shown that the scores of BOPPPS group were significantly rising, regardless of whether or not the students had studied radiobiology courses. Among the students who have not studied these courses, the scores were rising greatly. Moreover, From the analysis of different positions, it was found that both the scores of BOPPPS group and control group have risen, especially for doctors, deputy chief doctors, physicists and technicians. There were also statistically differences between different degrees, with significantly rise in scores for undergraduate and doctoral students ( Z=3.64, 4.18, P<0.001). Conclusions:The flexible application of BOPPPS teaching mode to the online education of such boring disciplines, like radiobiology, is of great significance to raise the theoretical basis of radiotherapy practitioners.
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Objective:Partial stereotactic ablative boost radiotherapy(P-SABR)is a method to deliver SABR boost to the gross tumor boost volume(GTVb), followed by conventionally fractionated radiotherapy to the whole tumor area(GTV). GTVb is the max volume receiving SABR while ensuring the critical organ-at-risk(OAR)falloff to 3 GyE/f. We investigated the potential advantage of proton therapy in treating bulky non-small cell lung cancer(the tumor length greater than 8 cm).Methods:Nine patients with bulky NSCLC treated with photon P-SABR in our institute were selected. For the treatment planning of proton therapy, the GTVb target area was gradually outwardly expanded based on the photon GTVb target area until the dose to critical OARs reached 3 GyE/f. The GTV and CTV areas remained the same as photon plan. A proton intensity-modulated radiation treatment plan(proton-IMPT), a photon intensity-modulated radiation treatment plan(photon-IMRT)and a photon volumetric modulated arc therapy(photon-VMAT)were created for each patient, respectively. The dosimetric parameters of different treatment plans were compared.Results:The volume ratio of GTVb-photon and GTVb-proton to GTV was(25.4±13.4)% and(69.7±30.0)%,respectively( P<0.001). In photon-IMRT, photon-VMAT, and proton-IMPT plan groups, the mean dose of CTV was(76.1±4.9)Gy, (78.2±3.6)Gy, and(84.7±4.9)Gy, respectively; the ratio of tumor volume with Biologic Effective Dose(BED)≥ 90 Gy to GTV volume was(70.7±21.7)%, (76.8±22.1)%,and(97.9±4.0)%,respectively. The actual dose and BED to the tumor area of the proton-IMPT plan group were significantly higher than those of the photon plan group(both P<0.05). Besides, the OARs dose was significantly decreased in the proton-IMPT group, with(49.2±22.0)%, (56.8±19.0)% and(16.1±6.3)% of the whole lung V5 for photon-IMRT, photon-VMAT and proton-IMPT, respectively(all P<0.001). Conclusions:Larger GTV boost target volume, higher BED and reduced OARs dose can be achieved in proton plans compared with photon plans. Proton P-SABR is expected to further improve the local control rate of bulky NSCLC with fewer adverse effects.
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Objective:To investigate the efficacy and safety of radiotherapy for all metastases in patients with metachronous oligo-metastatic prostate cancer after radical treatment.Methods:From October 2011 to February 2021, 41 patients with prostate cancer with less than 5 metastases after radical treatment were retrospectively analyzed in a single center. The median age at radiotherapy was 68 (57-81) years. Forty patients (98%) received androgen deprivation therapy (ADT). There were 28 patients in the hormone sensitive (HSPC) group and 13 patients in the hormone resistant (CRPC) group. The median initial PSA was 24.4 (7.4-399.0) ng/ml. Tumor stage: T 2 stage 11 patients, T 3 stage 27 patients, T 4 stage 3 patients.30 patients were in N 0 stage and 11 patients in N 1 stage. Gleason score was 7 in 12 patients, 8 in 9 patients, 9 in 18 patients, and 10 in 2 patients.33 patients were treated with surgery, and 8 patients were treated with radiotherapy. The time span from diagnosis to metastasis was 3.1 (0.2-1.8) years. Conventional imaging examination (CT/ MRI/bone scan) before radiotherapy was used in 7 patients, and PSMA PET/CT examination was used in 34 patients.The median PSA before radiotherapy was 1.3(0.1-33.8) ng/ml. There were 62 metastases in 41 patients, including 1 lesion in 28 patients, 2 lesions in 9 patients, 3 lesions in 2 patients, and 5 lesions in 2 patients. Fifty-four patients had bone metastases and eight had retroperitoneal lymph node metastases. Twenty-two bone metastases were located in the pelvis, 18 in the vertebral body, 12 in the ribs, one in the femur and one in the sternum.The median metastatic volume was 5.8(0.2-81.7) cm 3.Daily image-guided rotational intensity modulated radiotherapy was used to cover all metastases.Dose segmentation modes include 37.5Gy/7.5Gy/5F, 60Gy/3Gy/20F, 65-70Gy/2.6-2.8Gy/25F.The median biological effective dose (BED 3) was 120 (67-147) Gy. The primary endpoint was biochemical progression-free survival (BPFS), the secondary endpoints were acute and late toxic side effects, local relapse-free survival (LPFS), and overall survival (OS). Results:The median follow-up time was 21 months (range 5-72 months). All patients completed radiotherapy, and 16 patients had grade 1 to 2 acute toxicity and side effects, and no grade 3 or above acute and late stage side effects. 1-year LPFS was 97.1%.The 1-year and 2-year BPFS were 77.5% and 59.2%, respectively. The median BPFS time was 29 months (range 13.9-44.2 months). Univariate analysis showed that the HSPC group ( P<0.001) and the group with total metastatic volume ≤ 5.8cm 3 ( P=0.010) had higher BPFS. The median BPFS time was 37 months in the retroperitoneal lymph node metastases subgroup and 17 months in the bone metastases subgroup ( P=0.141). In the HSPC group, the median BPFS was 30(22-38) months. After radiotherapy, PSA decreased in all 28 patients, and increased in 6 patients. The median BPFS was 12(4-18) months. In the CRPC group, the median BPFS was 4(0-8) months. PSA decreased in 10 patients (76.9%) after radiotherapy, and PSA decreased in 6 patients. The median BPFS was 5(3-28) months. Three patients’PSA did not decrease after radiotherapy, and they were treated with new endocrine therapy drugs, chemotherapy, immunotherapy and other systemic therapy. Conclusions:For patients with metachronous metastases after radical treatment, full coverage radiotherapy has good safety and high local control rate. HSPC patients and patients with low tumor load could be recommended to receive radiotherapy for all metastatic lesions preferentially, and patients with only retroperitoneal lymph node metastases may have better prognosis after radiotherapy than patients with bone metastases.
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Objective:To evaluate the effect of setup errors from daily cone-beam computed tomography (CBCT) on the accumulated dose under different image-guidance (IG) strategies, aiming to investigate the appropriate IG strategies during radiotherapy for the spine metastases.Methods:A total of 720 CBCT scans of 36 vertebral lesions were obtained. All 36 lesions were divided into the simultaneous boosting (PTV 40 Gy/20f, GTV 60 Gy/20f, n=20) and conventional radiotherapy groups (PTV 40 Gy/20f, n=16). The actual fractionated plan was recalculated simulatively after transferring the isocenter of the initial plan according to the interfraction setup error. Under no daily image-guidance (no-DIG) strategies including twice imaging guidance weekly (TIG), initial 5 days then weekly imaging guidance (5D+ WIG), WIG and no imaging guidance (NIG), the dose deviation was calculated between the delivered dose accumulated by each actual fractionated plan and the dose distribution under DIG. The tolerance of dose deviation for the target was within ±5% and the D max of the spinal cord was limited below 45 Gy. Results:Under different image-guidance strategies of TIG, 5D+ WIG, WIG and NIG, the median dose deviation was approximately ±1% for the CTV D 95% and D max of spinal cord. However, the median dose deviation was beyond -5% for the PTV D 95% when conventional radiotherapy was given. The median dose deviation was approximately 10% for the D max of spinal cord and the proportion of cases whose maximum irradiated dose of spinal cord was more than 4500 cGy was ≥70%. Also, the median dose deviation was beyond -5% for the GTV D 95% and PTV D 95% when simultaneous boosting was delivered. Conclusions:Because the dose deviation of CTV and spinal cord is within the tolerance limit, the image-guidance strategies could be chosen according to the clinical practice when conventional radiotherapy is delivered. However, the dose deviation of spinal cord, GTV and PTV exceeds the tolerance limit under no-DIG strategies when simultaneous boosting is delivered. Hence, it is necessary to perform daily IGRT for the spine metastases.
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Objective:To explore the amplitude of normal kidney motion in the 3D direction and its influencing factors under free-breathing condition.Methods:Clinical data of 28 patients with a KPS score≥80 who received 4D CT scan from March 2018 to March 2019 were collected. All patients were diagnosed with liver, pancreatic or lung tumors. The kidney was outlined and the geometric center and 3D coordinate values were recorded. The motion of bilateral kidneys in each direction and the 3D direction was calculated. The volume of kidney and surrounding organs, age, sex, height and body mass index (BMI) were recorded. Clinical data were statistically compared by t-test or nonparametric test. Results:The motion of the left and right kidneys in the the sup-inf (SI) direction were the largest up to (8.39±3.18) mm and (7.71±3.55) mm. The motion amplitudes of bilateral kidneys in male patients were significantly larger than those of the female counterparts in the left-right (LR), SI and 3D directions (all P<0.05). The motion amplitudes of bilateral kidneys in patients taller than 165 cm were significantly larger than those of their counterparts with a height of ≤165 cm (all P<0.05). Patients with a BMI≥25 kg/m 2 had significantly larger motion amplitudes of the left kidney in the LR and ant-post (AP) directions compared with those of normal weight counterparts (all P<0.05). The motion amplitude of the left kidney in the AP direction in patients with the left kidney volume of >180 cm 3 was significantly larger than that of patients with smaller left kidney volume ( P=0.014). Age was not significantly associated with kidney motion in each direction ( P>0.05). Conclusions:Kidney motion mainly occurs in the SI direction. The kidney motion amplitudes in male and taller patients are larger. Special attention should be paid to the use of breath motion control device to decrease the normal tissue damage.
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Objectives:To investigate the efficacy and toxicity of the full coverage radiation to primary and all metastatic lesions in patients with oligometastatic castration-resistant prostate cancer (CRPC).Methods:Forty-four patients with oligometastatic CRPC was retrospective analyzed from Oct. 2011 to Jun. 2017 at Peking University 1 st Hospital. Before radiotherapy, average age was 72(57-86), the median value of initial PSA was 38.545 (6.640-1 066.000)ng/ml, the median value of PSA nadir after initial androgen deprivation therapy(ADT) was 0.259(0.011-18.762)ng/ml, the time interval between initial ADT to diagnosis of metastatic castration resistant prostate cancer(mCRPC) was 12(4-96) months, and the median PSA value pre-radiotherapy was 3.765(2.040-187.000) ng/ml. There were 23(52.3%)patients with Gleason score 9-10 and 15(34.0%) patients with Gleason score 8. At the time of initial diagnosis, there was 41(93.2%) cases with stage T 3-T 4, 23(52.3%)cases with lymph node metastasis, and 29 (63.9%) case with distant metastasis. The number of metastatic foci before radiotherapy was 1 in 22(50.0%)cases, 2 in 12(27.3%)cases, 3 in 6(13.6%)cases and 4 in 4(9.1%)cases. There were 3 cases of pelvic lymph node metastasis (6.8%), 9 cases of retroperitoneal lymph node metastasis(20.5%), 21 cases of bone metastasis(47.7%), 11 cases of bone metastasis+ lymph node metastasis(25.0%), and no visceral metastasis. Image-guided volumetric modulated arc therapy(IGRT-VMAT) was used to fully cover primary and metastatic foci. The prostate and seminal vesicle were routinely underwent 76Gy/38 fractions, and the bioequivalent dose(BED 3) was 126.67 Gy. For those with pelvic lymph node metastasis, the drainage area of pelvic lymph node was 46Gy/23 fractions. According to the tolerance of different normal tissues around the lesions, the median BED 3 of local radiotherapy dose in the metastatic foci was 112.26(91.14-140.77)Gy. The efficacy and side effects of all these patients were recorded. Kaplan-meier method was used to analyze the overall survival and the new metastasis-free survival. Results:Only 1 patient had grade 3 urinary tract obstruction and underwent indwelling catheter. All the other patients had grade 1-2 toxic and side effects. After a median follow-up of 34.5(9-96) months, the PSA-nadir after radiotherapy was 0.088(0.003-132.000)ng/ml. Forty(90.9%) patients showed a decrease in PSA after radiotherapy, and 34(77.3%) cases. showed a decrease of >80%. The 1, 3, and 5-year overall survival rates were 90.9%, 54.5%, 36.8%, the 1, 3, and 5-year new metastasis free survival rates were 47.7%, 25.0%, 12.9%, respectively.Conclusion:The full coverage radiotherapy to primary and metastatic lesions showed high PSA response rate, the satisfactory survival and tolerable toxicity in oligometastatic CRPC patients.
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Objective:To qualitatively analyze and auto-discriminate intrafraction prostate movement patterns based on transperineal ultrasound (TPUS) technique and linear discriminant analysis (LDA) method, which lays a solid foundation for individualized precise radiotherapy.Methods:A total of 1265 intrafraction motion trajectories and millions of monitoring data were recorded by TPUS from 61 prostate cancer patients. Seven typical patterns were considered: stable at baseline, slight transient excursion, persistent excursion and continuous drift, as well as obvious transient excursion, persistent excursion and continuous drift. Motion trajectory diagrams associated with the displacement-time function were generated by MATLAB programming. Valuable features were selected and different patterns were identified. Discriminant accuracy and receiver operating characteristic (ROC) curve were utilized to evaluate the performance of LDA model.Results:Four movement patterns were found per patient during the whole treatment process, and unstable type was occupied at (35.00±21.49)%. With the increase of treatment times, motion trajectories did not show an increasingly stable trend, and the appearance of different patterns was extremely irregular. After quantitative analysis, discriminant accuracy of LDA method was 90.4% for the training set and 89.5% for the testing set, with a sensitivity of 84.9% and a specificity of 91.1%.Conclusion:Intrafraction movement patterns are characterized by diversity and randomness. The LDA method can be used to discriminate different movement patterns effectively, and the unknown samples can be identified by discriminant equations and centroid coordinates.
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Objective:To evaluate the dosimetric properties of intensity-modulated proton therapy (IMPT) plans for simulated treatment planning in patients with ventricular tachycardia (VT) using stereotactic ablative body radiotherapy (SABR), in comparison with the volumetric-modulated arc therapy (VMAT).Methods:A total of 25 gross target volume (GTV) of the apical, anterior, septal, inferior and lateral wall of the left ventricle (LV) were delineated on the CT simulation images of 5 patients with complete data. An additional 5 mm GTV margin was added to the internal target volume (ITV), and an additional 3 mm ITV margin was added to the planning target volume (PTV). VMAT and IMPT plans were designed in each target area. Dose prescription was 25 Gy (RBE) in a single fraction. The dosimetric differences of ITV and organ at risk (OAR) were compared between VMAT and IMPT.Results:The median volume of ITV was 45.40 cm 3(26.72-67.59 cm 3). All plans had adequate target coverage(V 95%Rx≥99%). Compared with the VMAT plans, IMPT reduced the D mean of whole heart, pericardium and non-target cardiac tissues (relative difference) by 44.52%, 44.91% and 60.16%, respectively, which also reduced D 0.03 cm 3 of the left anterior descending artery by 17.58%( P<0.05). After stratified analysis according to the lesion sites, IMPT could still reduce the dose of most OAR. However, the D 0.03 cm 3 of LAD and LCX for the lesions in the anterior wall of LV, the D 0.03 cm 3 of LCX in the inferior wall and D 0.03 cm 3 of LAD in the apical wall did not significantly differ (both P>0.05). Conclusions:Both VMAT and IMPT plans can meet the clinical dosimetric requirements when SABR is simulated in patients with VT. However, IMPT can lower the dose of normal heart tissues, which has the potential benefit of reducing the risk of complications, such as ischemic heart disease, pericarditis/pericardial effusion, etc.
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Objective:To analyze the influencing factors of hemoglobin changes in prostate cancer patients during radiotherapy combined with androgen-deprivation therapy (ADT) and analyze the relationship between the hemoglobin changes and long-term prognosis.Methods:The changes of hemoglobin levels in 145 prostate cancer patients treated with radiotherapy combined with ADT in Department of Radiation Oncology of Peking University First Hospital from November 2011 to May 2015 were retrospectively analyzed. Intensity-modulated radiotherapy (IMRT) was employed for conventionally fractionated radiotherapy. Luteinizing hormone-releasing hormone agonist was utilized for endocrine therapy.Results:The median hemoglobin reduction during radiotherapy combined with ADT was 8 g/L. The higher the baseline level of hemoglobin, pelvic irradiation and GS score before radiotherapy, the more obvious the decrease of hemoglobin during treatment (all P<0.001). Pelvic radiotherapy significantly increased the decline tendency of hemoglobin throughout the combined treatment (86.8% vs. 72.8%, P=0.05). The duration of endocrine therapy before radiotherapy and the hemoglobin changes during endocrine therapy alone were not significantly correlated with the degree of hemoglobin decline during subsequent radiotherapy ( P=0.53 and 0.837). The biochemical failure-free survival did not significantly differ between patients with significant and mild hemoglobin reduction ( P=0.686). Conclusions:The baseline level of hemoglobin before radiotherapy is negatively correlated with the decrease of hemoglobin during combined therapy. Pelvic radiotherapy is positively correlated with hemoglobin reduction during combined therapy. Hemoglobin reduction during combined therapy is not associated with the long-term biochemical failure-free survival of patients.
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Objective@#To analyze the therapeutic effect and prognostic factors of induction chemotherapy plus intensity-modulated radiotherapy (IMRT) with or without consolidation chemotherapy for esophageal squamous cell carcinoma (ESCC).@*Methods@#One hundred and eight patients with ESCC treated between January 2010 to August 2014 were analyzed retrospectively. All patients received IMRT and platinum-based chemotherapy. The overall survival (OS) and local control (LC) rates were calculated using the Kaplan-Meier method and the univariate prognostic analyses were tested by the Log-rank test. The Cox proportional hazard model was used for multivariate prognostic analysis.@*Results@#The follow-up rate was 97.2%. The 1-, 3- and 5-year survival rates were 76.9%, 50.9% and 32.3% respectively, and the LC rates were 73.6%, 58.5% and 54.9% respectively. The median OS with and without consolidation chemotherapy were 51 and 15 months (χ2=5.076, P=0.024), respectively. Multivariate analysis showed that clinical N staging, recent curative effect and consolidation chemotherapy were important prognostic factors for OS, and recent curative effect was associated with LC. The rates of acute grade 3 radiation-induced esophagitis, gastrointestinal side effects, myelosuppression and radiation-induced pulmonary injury were 7.4%, 6.5%, 12% and 0.9%, respectively, and no grade 4 occurred. The late toxicity was mainly radiation-induced pulmonary fibrosis.@*Conclusions@#Induction chemotherapy plus IMRT with or without consolidation chemotherapy is safe and effective in the treatment of ESCC. The addition of consolidation chemotherapy may help prolong the survival of some patients and further research is necessary. Individualized treatment should be selected for patients who cannot tolerate or refuse concurrent chemoradiotherapy.
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Objective To analyze the therapeutic effect and prognostic factors of induction chemotherapy plus intensity-modulated radiotherapy (IMRT) with or without consolidation chemotherapy for esophageal squamous cell carcinoma (ESCC).Methods One hundred and eight patients with ESCC treated between January 2010 to August 2014 were analyzed retrospectively.All patients received IMRT and platinum-based chemotherapy.The overall survival (OS) and local control (LC) rates were calculated using the Kaplan-Meier method and the univariate prognostic analyses were tested by the Log-rank test.The Cox proportional hazard model was used for multivariate prognostic analysis.Results The follow-up rate was 97.2%.The 1-,3-and 5-year survival rates were 76.9%,50.9% and 32.3% respectively,and the LC rates were 73.6%,58.5% and 54.9% respectively.The median OS with and without consolidation chemotherapy were 51 and 15 months (x2 =5.076,P=0.024),respectively.Multivariate analysis showed that clinical N staging,recent curative effect and consolidation chemotherapy were important prognostic factors for OS,and recent curative effect was associated with LC.The rates of acute grade 3 radiation-induced esophagitis,gastrointestinal side effects,myelosuppression and radiation-induced pulmonary injury were 7.4%,6.5%,12% and 0.9%,respectively,and no grade 4 occurred.The late toxicity was mainly radiation-induced pulmonary fibrosis.Conclusions Induction chemotherapy plus IMRT with or without consolidation chemotherapy is safe and effective in the treatment of ESCC.The addition of consolidation chemotherapy may help prolong the survival of some patients and further research is necessary.Individualized treatment should be selected for patients who cannot tolerate or refuse concurrent chemoradiotherapy.
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Objective To assess the acute toxicity of a hypo-fractionated regimen of intensity-modulated radiotherapy to the prostatic bed after prostatectomy.Methods From February to August 2017,twenty cases with prostate adenocarcinoma after prostatectomy were recruited.The prescribed dose to the whole pelvis and the prostatic bed was 45 Gy delivered in 1.8 Gy per fraction and 62.75 Gy delivered in 2.51 Gy per fraction,respectively.Acute toxicity was recorded and graded according to Radiation Therapy Oncology Group (RTOG) criteria and Common Terminology Criteria for Adverse Events (CTCAE) 4.0.Results The median follow-up was 7.5 months.Grade 2 acute genitourinary and gastrointestinal toxicity was observed respectively in two cases (10%) and one (5%),respectively.Two cases (10%) complained of grade 2 urinary incontinence during radiation therapy,but recovered to grade 0 or grade 1 after the first month of follow-up.Conclusions After prostatectomy,moderately hypo-fractionated radiotherapy (2.51 Gy × 25) compared with conventional fractionated radiotherapy previously reported did not increase the risk of acute toxicity.The incidence of urinary incontinence did not increase during short-term of follow-up.
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Objective To evaluate the incidental irradiation to the axillary levels Ⅰ,Ⅱ and Ⅲduring the whole breast radiotherapy after breast conserving surgery(BCS)without axillary lymph node dissection(ALND)in breast cancer(BC)patients.Methods A retrospective analysis was performed on the consecutive 42 cases of T1-2N0M0stage BC patients with sentinel lymphnode biopsy(SLNB)and BCS but without ALND.The axillary lymph nodes of Ⅰ,Ⅱ and Ⅲ were delineated according to RTOG atlas guideline.Three radiotherapy plans including conventional tangential field(CTF),three-dimensional conformal radiotherapy(3D-CRT)and forward-planned intensity-modulated radiotherapy(IMRT)for whole breast irradiation were devised for each case.The Prescription dose was 50 Gy per 25 fractions.Doses to axillary levels(Ⅰ-Ⅲ)were evaluated.Results The mean doses delivered to axillary by the three techniques(CTF,3D-CRT and IMRT)were(40.1 ±6.8),(35.4 ±8.3),(32.9 ±7.0)Gy for level Ⅰ(F=10.269,P<0.05),(33.2 ±7.1),(30.6 ±6.7),(30.4 ±7.0)Gy for level Ⅱ(P>0.05)and(9.6 ±6.8),(6.4 ±4.5),(5.2 ±3.7)Gy for level Ⅲ(F =8.377,P <0.05),respectively.V50(volume receiving 50 Gy)for the three techniques were 21.3%,27.6%,9.6%for level Ⅰ(F=13.161,P<0.05),12.9%,15.9%,8.3%for level Ⅱ(F=2.750,P<0.05)and 0.4%,0.1%and 0%for level Ⅲ(P>0.05),respectively.Conclusions The doses coverage to axillary levelsⅠ-Ⅲwere all limited in the three techniques.Therefore,it is necessary to assess the risk of axillary lymph node metastasis adequately to develop individualized radiotherapy plans.
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Objective To analyze the adverse events in patients diagnosed with oligometastasized castration resistant prostate carcinoma (CRPC) receiving radiotherapy for the primary and metastatic prostate carcinomas.Methods Twenty patients with oligometastasized CRPC admitted to our hospital between 2011 and 2015 were treated with image-guided volumetric modulated arc therapy (VMAT).The dose for prostate+ seminal vesicle was 76 Gy/38 f,46 Gy/23 f for the pelvic lymph node and the median dose for the metastatic lesions was 60 Gy (52-66)/23 f.Relevant clinical data and adverse events were analyzed.Results All patients completed the radiotherapy.Only 1 patient showed grade Ⅲ urinary obstruction and received catheterization.In terms of acute adverse events of ≥ grade Ⅱ,urinary tract was observed in 4 cases (20%),rectum in 2 (10%) and blood system in 2(10%).The rectal V50 was correlated with acute adverse events of ≥ grade Ⅱ.The median follow-up time was 24.2 months.No patient suffered from late adverse events of ≥ grade Ⅱ.All cases showed a decline in the level of prostate specific antigen (PSA) after radiotherapy.The median PSA reduction rate was 99%.Among them,16 cases (80%) had a PSA reduction rate of over 90%.Conclusions It is safe and efficacious to perform radical dosage radiotherapy for primary and metastatic prostate carcinomas in patients with oligometastasized CRPC.
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Objective To compare the toxicity between different dose fractionation regimens in postoperative radiotherapy for prostate cancer. Methods Patients with prostate cancer who received postoperative radiotherapy with moderate hypo-fractionation ( 62. 75 Gy in 25 fractions, 2. 51 Gy per fraction) or conventional fractionation (72 Gy in 36 fractions, 2 Gy per fractions) in our hospital from 2011 to 2017 were enrolled as subjects.All patients received intensity-modulated radiotherapy and daily cone-beam computed tomography image-guided radiotherapy. According to the propensity score matching ( PSM ) method, 35 patients treated with moderately hypo-fractionated radiotherapy were matched to 35 patients treated with conventionally fractionated radiotherapy based on age, irradiated volume, hormonal therapy, interval between surgery and radiotherapy, and comorbidities ( diabetes and hypertension). Toxicity was evaluated according to Radiation Therapy Oncology Group criteria. Comparison was made by the Fisher's exact probability test. Results One hundred and thirteen patients, consisting of forty-one in moderate hypo-fractionation group and seventy-two in conventional fractionation group, were enrolled as subjects. The median follow-up time in the two groups was 5. 6 and 45. 0 months, respectively. There were no significant differences in incidence rates of grade 2 acute gastrointestinal (GI) or genitourinary (GU) toxicity between the two groups ( 7% vs. 7%, P= 1. 000; 15% vs. 17%, P= 0. 847). After PSM, there were still no significant differences in incidence rates of grade 2 acute GI or GU toxicity between the two groups (9% vs. 11%, P=0. 814; 14% vs. 11%, P= 0. 670). None of patients reported ≥grade 3 GI or GU toxicity. Conclusions Preliminary results show that moderate hypo-fractionation, compared with conventional fractionation, does not increase the risk of acute GI or GU toxicity in patients undergoing postoperative radiotherapy for prostate cancer.
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Objective To apply real-time transperineal ultrasound ( TPUS) to monitor the intra-fractional prostate motion,collect and analyze the data of the prostate motion,aiming to provide evidence for the optimization of the target area and plan of radiotherapy for prostate cancer. Methods TPUS is a non-invasive monitoring technique that utilizes an automatic scanning ultrasound probe to dynamically monitor and correct the motion of organs during radiotherapy. In this study, TPUS was utilized to collect 1588 intra-fractional data of 70 patients with prostate cancer. Prior to each cycle of radiotherapy,CBCT was adopted to correct the errors between intra-factional data by using VMAT. During radiotherapy, real-time ( once per second) ultrasound images were acquired to monitor the 3D motion of the prostate on the x (left+,right-),y (cranial+, caudal-), and z ( abdominal+, dorsal-) axes, emphasizing the analysis of 4D motion of the prostate. Results All patients successfully completed the treatment and data collection. The median time of effective monitoring per faction was 179 seconds (132-286 seconds). During 95% of the monitoring time,the distance of prostate motion was 2. 22 mm in the left direction,2. 17 mm in the right,2. 08 mm in the cranial, 1. 98 mm in the caudal,2. 44 mm in the abdominal and 2. 97 mm in the dorsal direction,respectively. In the x,y and z axes,the percentage of time in which the distance of prostate motion less than 1 mm among the total time was 83. 07%,85. 46% and 78. 27%,respectively,whereas 97. 70%,97. 87% and 96. 45% for<3 mm, respectively. Conclusions TPUS is a non-invasive real-time monitoring technique,which can detect the 4D motion of the prostate during radiotherapy. By using VMAT,the range of prostate motion is relatively small, and the motion range is less than 3 mm in each direction within 95% of the time.
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Objective To compare the efficacy and adverse effects of hypofractionated radiotherapy versus conventionally fractionated radiotherapy for intermediate-to high-risk localized prostate cancer.Methods A literature search was performed in PubMed, Embase, Web of Science, CNKI, VIP database, and Wanfang Data to collect the controlled clinical trials of hypofractionated radiotherapy versus conventionally fractionated radiotherapy in patients with intermediate-to high-risk localized PCa published up to August 31, 2016.Stata 12.0 was used for meta-analysis.The difference between two groups was estimated by calculating the hazard ratio (HR) or risk ratio (RR) with 95%confidence interval (CI).ResultsAccording to the inclusion and exclusion criteria, a total of 5 controlled clinical trials involving 1621 patients with PCa were included in this meta-analysis.The meta-analysis showed that overall survival (HR=1.00, 95%CI:0.85-1.17, P=0.980) and biochemical failure (RR=0.87, 95%CI:0.68-1.12, P=0.274) were comparable between the two groups.Compared with the conventionally fractionated radiotherapy, the incidence of acute gastrointestinal adverse events (grade≥2) was significantly higher in the hypofractionated radiotherapy (RR=1.94, 95%CI:1.23-3.06, P=0.004).However, there were no significant differences in the incidence of acute genitourinary adverse events (grade≥2)(RR=1.03, 95%CI:0.92-1.14,P=0.626), late gastrointestinal adverse events (grade≥2)(RR=1.17,95%CI:0.90-1.51, P=0.238), and late genitourinary adverse events (grade≥2)(RR=1.11, 95%CI:0.94-1.30, P=0.228) between the two groups.Conclusions Conventionally fractionated radiotherapy and hypofractionated radiotherapy have comparable therapeutic effects in patients with intermediate-to high-risk localized PCa.Although the patients treated with hypofractionated radiotherapy have a higher incidence of acute gastrointestinal adverse events than those treated with conventionally fractionated radiotherapy, the incidence of late gastrointestinal and genitourinary adverse events is comparable between the two groups of patients and the adverse effects are tolerable.