Objective To evaluate the efficacy of salvage radiotherapy for supraclavicular lymph node metastasis ( SLNM) after initial treatment in patients with esophageal cancer. Methods A total of 117 patients with SLNM after radical resection for esophageal cancer were enrolled as subjects from 2006 to 2012. All patients received three?dimensional radiotherapy with 1. 8?2. 0 Gy per cycle, 5 cycles a week. The survival rates were calculated using the Kaplan?Meier method and analyzed using the log?rank test. The Cox model was used for multivariate analysis. Results The follow?up rate was 100%. In all the patients, the 1?and 3?year overall survival (OS) rates were 38. 5% and 14. 1%, respectively. The 1?and 3?year OS rates were significantly higher in patients treated with salvage radiotherapy or radiochemotherapy ( n=100) than in patients without any salvage treatment (n=17)(42% vs. 18%,P=0. 008;17% vs. 0%, P=0. 008). The patients treated with radiochemotherapy ( n=32) had significantly higher 1?and 3?year OS rates than those treated with radiotherapy alone (n=68)(59% vs. 34%, 36% vs. 11%, P=0. 002) or without any salvage treatment (n=17)(59% vs. 18%, 36% vs. 0%, P=0. 002). Patients without visceral metastasis (n=80) had significantly higher 1?and 3?year OS rates than those with visceral metastasis ( n=37) ( 44% vs. 27%, P=0. 002;22% vs. 0%,P=0. 002) . Patients with supraclavicular doses of ≥60 Gy in salvage radiotherapy ( n=75) had significantly higher 1?and 3?year OS rates than those with supraclavicular doses of<60 Gy in salvage radiotherapy ( n=25) ( 75% vs. 25%,P=0. 000;24% vs. 8%,P=0. 000) . The multivariate analysis using the Cox model showed that supraclavicular doses of ≥60 Gy, mediastinal metastasis, visceral metastasis, and salvage treatment method were independent factors for survival ( P=0. 001,0. 015,0. 009, 0. 025) . Conclusions Salvage radiotherapy can improve the survival of patients with SLNM in esophageal cancer. Salvage radiotherapy or radiochemotherapy is highly recommended for patients with SLNM alone. A radiation dose of ≥60 Gy in salvage radiotherapy improves survival in patients.

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.

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.

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.

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 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.

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.

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.