Objective To explore the relationship between the peripheral dose and radioactive counts of 125I seeds detected by SPECT/CT.Methods Six 125I seeds(1.48×107 Bq, 1.85×107 Bq, 2.22×107 Bq, 2.59×107 Bq, 2.96×107 Bq, 3.33×107 Bq) were put into the solid water phantoms respectively. SPECT/CT was applied to scan the seeds. The radioactive counts (x) at the distance of 1-15 mm from the center of seeds were recorded respectively, while the corresponding doses (y, cGy) were calculated. SPSS 18.0 was used to analyze the relationship between the radioactive counts and peripheral dose. Results There was an exponential relationship between the peripheral dose of 125I seeds and the radioactive counts. The formula was as follow: y=507.849×1.004x. Conclusion SPECT/CT can visualize the peripheral dose of 125I seed, which may provide a method for dosimetric verification after brachytherapy.

Objective To investigate the dosimetric effect of same activity and same number of 125I seeds arranged in axial train but with different spacing.Methods A total of 27 film dosimeters were randomly and equally divided into group A,B and C.Each film was irradiated by three 125I seeds (activity of 1.48×107 Bq).The seeds were arranged in line,and their axial spacing was 1 mm,5 mm and 10 mm respectively.Image analysis software was used to draw iso-gray contour curves of 20,25,30 and 40 gray value on the films,and to calculate the areas contained by each curve.Results Multi-sample mean comparison variance analysis showed that the differences in area contained by 20 and 25 iso-gray contour curves were statistically significant between each other among the three groups (P＜0.001).The difference in area contained by 30 iso-gray contour curve between group A and group B was not statistically significant (P＞ 0.05),while the difference in area contained by 30 iso-gray contour curve between group A and group C as well as between group B and group C was statistically significant (P＜0.001).No statistically significant difference in area contained by 40 iso-gray contour curve existed between each other among the three groups (P=0.99).Conclusion Different spacing arrangement of same activity and same number of 125I seeds can directly influence the peripheral dose distribution.In specific dose range,seed-spacing of 1 mm arrangement may obtain better dose distribution than seed-spacing of 5 mm or 10 mm arrangement can do.

ObjectiveTo explore the effective components， targets， and mechanism of Houttuynia cordata against lung cancer by means of systems pharmacology and further to provide a reference for the further development and clinical application of this medicinal. MethodChemical components of H. cordata were retrieved from Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform （TCMSP） and the active components were screened based on oral bioavailability （OB） and drug-likeness （DL）. Then the potential targets were predicted， followed by enrichment analysis. Finally， sodium houttuyfonate （SH） was selected for verifying the anti-tumor mechanism. Cell counting kit-8 （CCK-8） assay was used to evaluate the effect of SH on the in vitro proliferation of two lung cancer cell lines： A549 and LLC， and the regulation of tumor-related proteins by SH was verified by Western blot. ResultA total of 7 active compounds and 352 targets of the active components were screened out. According to the enrichment analysis of targets， H. cordata had potential therapeutic effects on cancer. SH had inhibitory effect on both A549 and LLC. Western blot results showed that G₁/S-specific Cyclin D₁， E₁ and cyclin-dependent kinase （CDK）2， CDK4 all tended to be down-regulated， and Janus kinase 2 （JAK2）/signal transducer and activator of transcription 3 （STAT3） also changed significantly. ConclusionH. cordata has the potential anti-tumor effects by arresting the tumor cells in the G₁ phase through the JAK2/STAT3 pathway.

Objective:To investigate the relationship between dosimetric parameters and tumor volume change after 125I implantation for thyroid cancer and obtain better dosimetric parameters that predict the curative effect more accurately. Methods:A total of 22 consecutive patients with thyroid cancer (23 targets) who received 125I interstitial brachytherapy in Department of Oncology, Hebei General Hospital were retrospectively analyzed. All the patients received post-operative dose verification, and the D 90 (Minimum dose received by 90% target volume) was calculated. After a regular follow-up, the tumor volume reduction ratio after t months (R t) , actual absorbed dose (D 1m) , efficacy corrected absorbed dose (D 1e) , and sensitivity corrected absorbed dose (D 1s) of the first month were calculated according to the actual follow-up CT images. The statistical test was carried out by SPSS21.0. The Spearman linear analysis was applied to analyze the relationship between D 90, D 1m, D 1e, D 1s and R t, and the curve fitting was also completed. Results:The post-operative D 90, D 1m, D 1e, D 1s and R t were (129.73±14.22) Gy, (36.95±7.35) Gy, (43.45±11.32) Gy, (41.78±13.39) Gy, and (32.00±19.00) %, respectively. And the correlation coefficient were 0.692, 0.551, 0.728, and 0.858, respectively, which showed significant positive relevance between dosimetric parameters and tumor volume change ( P<0.01) , the curve fitting presented cubic function. Conclusion:The post-operative D 90, D 1m, D 1e, and D 1s can be predictors for curative effect, and D 1s is the best predictor.

Objective:To investigate the incidence of radiation pneumonitis (RP) induced by 125I seed implantation for the treatment of malignant lung tumors and analyze related dosimetric parameters. Methods:A retrospective analysis was conducted on 31 cases of malignant lung tumors treated with 125I seed implantation from January 2017 to December 2022 at Hebei Provincial Tumor Radioactive Seeds Implantation Diagnosis and Treatment Center. These cases consisted of eight patients with squamous cell carcinoma, 10 patients with adenocarcinoma, and 13 patients with metastatic cancer in other sites. At 1-6 months after treatment, these patients received postoperative chest CT scans, with the efficacy evaluated based on the Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1), including the objective response rate (ORR) and the disease control rate (DCR). The efficacy of RP was evaluated using the Radiation Therapy Oncology Group (RTOG) criteria. Postoperative dosimetric parameters, including D90 (minimum peripheral dose received by 90% of the target volume), V8 (percentage of lung volume receiving 8 Gy), V32 (percentage of lung volume receiving 32 Gy), and Dmean (mean radiation dose) of the affected lung, were statistically analyzed. The relationships of the RP occurrence with postoperative D90, V8, V32, and Dmean were analyzed by comparison with relevant external radiotherapy data, to identify the parameters that are correlated closely with RP occurrence. Results:All the patients underwent successful surgeries. The postoperative efficacy evaluation after six months showed complete response (CR) in 11 cases, partial response (PR) in 11 cases, stable disease (SD) in eight cases, and progressive disease (PD) in one case, with an overall response rate (ORR) of 71.0%, and a disease control rate (DCR) of 96.8%. Three patients suffered RP, with an incidence rate of 9.7%. Postoperative V8, V32, and Dmean could not serve as predictive indicators for RP. Follow-up observation revealed that three RP cases (3/5) exhibited postoperative D90 exceeding 170 Gy and no RP cases (0/26) showed postoperative D90 below 170 Gy. Conclusions:In the treatment of malignant lung tumors with 125I seed implantation, there is a certain correlation between RP and postoperative D90, while there is no correlation between it and V8, V32, and Dmean.

Objective: To analyze the factors influencing the short-term efficacy of CT-guided ¹²⁵I seeds implantation in the treatment of recurrent and metastatic tumors in head and neck. Methods: A total of 73 patients (61 males, 12 females; age: (59.1±11.5) years) with head and neck tumors recurrence and metastasis treated by ¹²⁵I seeds implantation in Hebei General Hospital from January 2015 to April 2019 were retrospectively enrolled. The implanted seeds activity was 11.1-29.6 MBq, and the prescription dose was 80.0-145.0 Gy. CT examination was conducted 3 months after ¹²⁵I seeds implantation. According to Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, short-term efficacy was classified as effective (complete remission (CR), partial remission (PR)) and ineffective (stable disease (SD), progressive disease (PD)). Univariate analysis of factors affecting short-term effect (gender, age, history of radiation therapy, Karnofsky performance status (KPS) scores, pathological type, the longest diameter of tumor, implantation patterns, seeds activity, immediate postoperative dose delivered to 90% gross tumor volume (D₉₀), and with adjuvant chemotherapy post-surgery or not) were conducted. Variables with P<0.2 were enrolled in logistic multivariate regression analysis. In addition, artificial neural network (ANN) was constructed with all influencing factors as independent variables and short-term efficacy as dependent variables. Finally, receiver operating characteristic (ROC) curve analysis was performed for the common influencing factors in logistic regression analysis and ANN analysis. Results: There were 34 with effective results and 39 with ineffective results. Logistic regression analysis indicated that the longest diameter of tumor, immediate postoperative D₉₀, with adjuvant chemotherapy post-surgery or not had significant impacts on the short-term efficacy (Wald values: 6.950, 4.804, 4.790, all P<0.05); According to results of ANN analysis, the top 5 in order of importance for short-term efficacy prediction were immediate postoperative D₉₀, the longest diameter of tumor, age, seeds activity and gender. ROC curve analysis indicated that the longest diameter of tumor and immediate postoperative D₉₀ were the best predictors for short-term efficacy, with the threshold of 5.25 cm and 110.05 Gy respectively, and the area under the curve (AUC) was 0.843 and 0.847 respectively (both P<0.001). Conclusions The short-term efficacy of ¹²⁵I seeds implantation in the recurrence and metastasis of head and neck tumors is mainly related to the longest diameter of tumor and immediate postoperative D₉₀. Patients with the longest diameter of tumor <5.25 cm and with D₉₀>110.05 Gy can achieve better efficacy.