Objective To study the feasibility of dose calculation using kilovoltage X-ray cone-beam CT (KVCBCT) imaging for head-and-neck radiation therapy.Methods 11 patients with nasopharyngeal carcinoma were scanned with KVCBCT to adjust position before treatment, and rescanning images with KVCBCT after correction were input a treatment-planning system.The dose was recalculated by applying the patients′ treatment plans based on planning CT to the KVCBCT images.The dose distributions and dose volume histograms (DVH) of the tumor and critical structures were compared with the original treatment plan.Results The DVH and dose distribution of the plan based on the KVCBCT are compared with that of the planning CT, and they shows a good consistency for the 11 cases.The doses calculated from the planning CT and KVCBCT were compared on the isocenter planes.Using γ analysis with a criterion of 3%/3 mm, 98.0%±1.33% of the points on the isocenter planes in the planning CT and KVCBCT.The difference of the dose to target volume was<1% and to normal structure was<2%.Conclusions This study indicated that CBCT images can be used to make a treatment plan with its individual hounsfield unit-electron density calibration curve.

ObjectiveTo analyze the correlation between primary tumor volume (PTV) and prognosis of nasopharyngeal carcinoma ( NPC ) treated by intensity-modulated radiotherapy ( IMRT ).Methods330 NPC patients treated by IMRT were included.Pretreatment computerized tomography image were input into tree-dimensional treatment-planning system,in which the primary tumor volume were calculated automatically.The receiver operating characteristic curve was used to determine the best cut-off point of PTV.Within the framework of UICC 2002 T stage,The PTV was divided into four groups:V1 ＜ 10cm3,V2 10-25 cm3,V3 ＞ 25-50 cm3 and V4 ＞ 50 cm3.Kaplan-Meier and Logrank test was used to analyze the survival,Cox proportion risk regression model were used to analysis the correlation between PTV and prognosis.ResultsThe mean PTV for all NPC patients was ( 34.2 ± 27.1 ) cm3 with the range of 0.4- 153.7 cm3.The 3-year overall survival for V1,V2,V3 and V4 stage were 88.6％,90.0％,91.2％ and 74.2％,respectively (x2 =12.83,P =0.005 ).There was no significant difference among V1,V2 and V3in terms of overall survival ( x2 =1.96,P =0.376).The 3-year distant metastasis-free survival and diseasesfree survival or overall survival were decrease in PTV ＞50 cm3 and PTV≤50 cm3 (77.4％:89.9％,x2 =7.24,P=0.007and 64.5％:85.1％,x2 =13.95,P=0.000 or 74.2％:90.3％,x2 =11.76,P=0.001).Multivariate analysis revealed that PTV was a adverse prognostic factors for overall survival (x2 =0.00,P =2.580).ConclusionOur data showed that the primary tumor volume had significantly impacted on the prognosis of NPC patients treated by intensity modulated radiotherapy.

Objective To measure the set-up errors of patients with head and neck (H&N) cancer during the image guided intensity-modulated radiotherapy (IMRT) treatment and analyze the impact of setup errors on dose distribution ; then to further investigate the necessity of adjustment online for H&N cancer during IMRT treatment.Methods Cone-beam CT (CBCT) scanning of thirty patients with H&N cancer were acquired by once weekly with a total of 6 times during IMRT treatment.The CBCT images and the original planning CT images were matched by the bony structure and worked out the translational errors of the x,y,z axis,as well as rotational errors.The dose distributions were recalculated based on the data of each setup error.The dose of planning target volume (PTV) and organs at risk were calculated in the replanning,and than compared with the original plan by paired t-test.Results The mean value of x,y,z axis translational set-up errors were ( 1.06 ± 0.95 ) mm,( 0.95 ± 0.77 ) mm and ( 1.31 ± 1.07 ) mm,respectively.The rotational error of x,y,z axis were ( 1.04 ±0.791 ),( 1.06 ±0.89) and (0.81 ±0.61 ),respectively.PTV 95％ volume dose ( D95 ) and PTV minimal dose of replanning for 6 times set-up were lower than original plan (6526.6 cGy:6630.3 cGy,t =3.98,P =0.000 and 5632.6 cGy:5792.5 cGy,t =- 2.89,P =0.007).Brain stem received 45 Gydose volume ( V45 ) and 1％ brain stem volume dose ( D01 )were higher than original plan ( 3.54％:2.75％,t =3.84,P =0.001 and 5129.7 cGy:4919.3 cGy,t =4.36,P =0.000).Conclusions The set-up errors led to the dose of PTV D95 obviously insufficient and significantly increased V45,D01 of the brainstem.So,adjustment online is necessary for H&N cancer during IMRT treatment.

Cone-beam CT (CBCT) of Elekta can be used to analyze the setup errors in intensity modulated radiotherapy. A total of 240 patients with head and neck cancer were chosen in the period from October, 2009 to October, 2010. Their CBCT images were obtained after initial setup, and registered to the planning CT images, and then the setup errors on translational directions (X, Y, Z) and on rotational directions (U, V, W) were obtained and analyzed. The results showed that the setup errors on translational directions in Y-axis and Z-axis were larger than in X-axis, and the setup errors on rotational directions in Y-axis was much more obvious than those on the other two directions, which should be taken care during the patient daily setup. It may be concluded that the CBCT system can improve the precision for radiotherapy.
Cone-Beam Computed Tomography ; methods ; Head and Neck Neoplasms ; diagnostic imaging ; radiotherapy ; Humans ; Radiotherapy Setup Errors ; prevention & control ; statistics & numerical data ; Radiotherapy, Intensity-Modulated

Objective:To investigate the expression of long non-coding RNA (Lnc RNA) RP5-919F19 in gastric cancer tissues and its correlation with gastric cancer invasion and metastasis.Methods:Non-tumor gastric mucosa (more than 3cm away from the cancer tissue) and gastric adenocarcinoma tissues were collected from Jan. 2020 to Jan. 2022 in our hospital. TRIzol kit was used to extract total RNA from cells and tissues, and reverse transcription kit was used to reverse transcribed RNA into cDNA. Quantitative real-time PCR kit was used for quantitative analysis. SGC-7901 and AGS human gastric cancer cells were used to construct RP5-919F19 knockdown and overexpression models. CCK-8 assay was used to confirm cell proliferation, and Transwell invasion assay was used to confirm the invasion ability of gastric cancer cells.Results:The expression of RP5-919F19 was detected in 79 cases of gastric cancer tissues and adjacent normal tissues, and it was found that the relative expression of RP5-919F19 in gastric cancer tissues was 1.51±0.05 significantly higher than that of 0.82±0.04 in adjacent normal tissues ( P<0.05) . The levels of RP5-919F19 in patients with different pathological conditions were compared and analyzed. The results showed that there were statistically significant differences in RP5-919F19 expression in patients with different TNM stages, distant metastasis, lymph node metastasis and different depth of invasion ( P<0.05) . There was no significant difference in RP5-919F19 expression among patients with different tumor sizes, ages and genders ( P>0.05) . AGS gastric cancer cells were transfected with RP5-919F19 overexpression plasmid and control plasmid, and the efficiency of RP5-919F19 was detected. The results showed that the expression level of RP5-919F19 in the overexpression group was 1.83±0.14 higher than that of 0.82±0.05 in the control group ( P<0.05) . SGC-7901 gastric cancer cells were transfected with RP5-919F19 knockout vector and control vector, and the efficiency of RP5-919F19 was detected. The results showed that the expression level of RP5-919F19 in the knockout group was 0.42±0.07 lower than that of 0.89±0.08 in the control group ( P<0.05) . CCK-8 was used to detect the proliferation ability of gastric cancer cells. The results showed that the proliferation ability of AGS cells in RP5-919F19 overexpression group was significantly increased compared with that of the control group at 24 and 48h after culture ( P<0.05) . However, the proliferation ability of SGC-7901 cells in RP5-919F19 knockdown group was lower than that in the control group at 24 h and 48 h ( P<0.05) . Transwell invasion assay showed that the invasion and migration abilities of AGS cells in RP5-919F19 overexpression group were higher than those in the control group ( P<0.05) , and the invasion and migration abilities of SGC-7901 cells in RP5-919F19 knockout group were lower than those in the control group ( P<0.05) . Western blot showed that compared with control cells, the expression of MMP-2 and MMP-9COPS7A proteins in down-regulated Lnc RNA RP5-919F19 SGC-7901 cells was decreased. Conclusion:The expression of LncRNA RP5-919F19 is abnormally increased in gastric cancer tissues, and the increased expression of RP5-919F19 can promote the proliferation and metastasis of gastric cancer cells.

Objective To investigate the precision of full six-degree target shift corrections using the ArcCHECK system.Metbods Fourteen patients receiving intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma (NPC) in Fujian Medical University Cancer Hospital from May to September,2015 were selected.The first treatment setup errors were obtained using cone-beam computed tomography.The setup errors were simulated in ArcCHECK,and the full six-degree target shift corrections was used to correct the errors.The plans without and with setup errors and the plan with corrected setup errors were taken.The paired t-test was used to compare dose to agreement (DTA) and Gamma passing rates between the plan without setup errors and the plan with setup errors and plan with corrected setup errors.Results The DTA and Gamma passing rates were (96.76± 1.57)％ and (98.35±0.92)％ for the plan without setup errors,(59± 21.42) ％ and (62.86± 21.63) ％ for the plan with setup errors,and (91.41± 4.82) ％ and (94.11±4.33)％ for the plan with corrected setup errors.There were significant differences between the plan without setup errors and the plan with setup errors and plan with corrected setup errors in DTA passing rate (t=6.64 and 5.13,both P＜0.05) and Gamma passing rate (t=6.15 and 4.19,both P＜0.05).Conclusions The full six-degree target shift corrections can be used in IMRT for NPC,with good results in correcting setup errors and improving the precision for IMRT dose distribution.

【Objective】 To investigate whether the current retention methods in blood stations can fully meet the traceability requirements of blood test results by analyzing the traceability of retained samples for syphilis antibody testing. 【Methods】 Thirty-four one-assay-positive deep-well plate retention samples, 68 double-assay-positive deep-well plate retention samples and 263 negative retention blood braids and corresponding deep-well plate retention samples that expired retention period for syphilis antibody testing from 2014 to 2020 in our center were collected. The TP-ELISA assays of two manufacturers were used for retesting, and the results were recorded and compared with the original results statistically. 【Results】 The concordance rate of the double-assay-positive and single-assay-positive samples with their corresponding deep-well plate samples was 98.53%(67/68) and 67.65%(23/34), respectively(P<0.05). Specific results for single-assay-positive syphilis antibody samples and their corresponding deep-well plate retention samples were as follows: 1) Single positive (reagent A): 13 out of 14 original samples were 0.65