Objective:To explore the radiological damage to cells induced by the delayed particles of 9C-ions for heavy ion therapy, as well as the microdosimetric distribution and biological effects of these particles on a single model of V79 Chinese hamster lung cells. Methods:The Monte Carlo program was employed to simulate the endonuclear absorbed doses of α particles with various energies (3-10 MeV) transported in cells (cell radius RC = 10 μm, nucleus radius RN = 5 μm). Then, the result were compared with the S values ( SN←N, SN←Cy, and SN←CS) derived using the medical internal radiation dose (MIRD) method to demonstrate the feasibility of Monte Carlo simulations. Finally, the energy deposition of the delayed particles of 9C-ions generated at three sites (i.e., on the surface and in the cytoplasm and nucleus of the V79 cell model) during their transport in targets was simulated, and the result ing cell surviving fraction was analyzed. Results:Monte Carlo and MIRD method yielded differences in S values of 1.91%-4.95% for SN←N (nucleus to nucleus), 1.48%-5.11% for SN←Cy (cytoplasm to nucleus), and -1.99% to 0.80% for SN←CS(surface to nucleus), indicating highly consistent S values derived using both method(differences < 6%). When a 9C-ion decayed on the surface of the V79 cell model and the produced secondary particles entered the cell, the average endonuclear absorbed dose was 10 -2 Gy orders of magnitude, with a cell surviving fraction of about 88%. In the case where decay occurred in the cytoplasm, the cell surviving fraction was about 80%. However, when the 9C ion decayed in the nucleus, α particles had short ranges and deposited most of their energy in the cell (mean endonuclear absorbed dose: 0.1 Gy). In this case, severe cell damage was induced, with the cell surviving fraction reducing to about 53%. Conclusions:9C-ions emit secondary charged particles due to decay, among which α particles cause great damage to cells when entering the nucleus and trigger evident biological effects.

Objective:To study the effects of gantry acceleration limitations of a linear accelerator (linac) on the dosimetry of volumetric modulated arc therapy (VMAT) plans, machine efficiency, and dose verification result of VMAT plans and to explore the optimal selection of gantry motion models in the Pinnacle treatment planning system.Methods:Ten cases of nasopharyngeal carcinoma, non-small cell lung cancer, sigmoid adenocarcinoma with retroperitoneal lymph node metastasis, and invasive ductal carcinoma of the breast were each selected for this study. Then two models were set up in the Pinnacle v9.10 treatment planning system, namely the one allowing gantry acceleration and the one limiting gantry acceleration. The same field arrangement, optimized target parameters, and optimized weights of VMAT plans were adopted in the two models, in order to analyze the dosimetric variations in targets and organs at risk (OARs) and compare the differences in treatment time and gamma passing rates.Results:The treatment time of the enrolled patients under the model allowing gantry acceleration was significantly lower than that of the patients under the model limiting gantry acceleration was adopted ( t=-6.751, -0.209, -19.523, -28.999; P< 0.05) and decreased by 15.27%, 18.07%, 19.71%, and 28.75%, respectively. Meanwhile, the conformity and uniformity of target areas were affected, while there was no statistical significance in the gamma passing rates in the validation of VMAT plans ( P>0.05). For the cases of nasopharyngeal carcinoma (NPC), the maximum dose to brainstem PRV increased by 1.25%. For the cases of lung cancer, the maximum dose to the spinal cord and lung V20 increased by 1.19% and 1.21%, respectively, while lung V5 decreased by 1.21%. For the cases of sigmoid adenocarcinoma with retroperitoneal lymph node metastasis, the mean doses to bilateral kidneys, livers, small intestine, and colon all increased. For the cases of breast cancer, lung V10 on the opposite side of cancer increased by 1.66% and the mean dose to the lungs on the same side of cancer decreased by 7.45%. Conclusions:The model allowing gantry acceleration allows the treatment time to be significantly shortened and the treatment efficiency improved. Although this model had the shortcomings such as affecting the conformity and uniformity of target areas to a certain extent and increasing the doses to some OARs, clinical requirements for dosimetry were still met. Therefore, it is recommended to use the model allowing gantry acceleration in the Pinnacle planning system.

Objective: To evaluate the long-term effect and safety of chrono-chemotherapy combined with intensity modulated radiotherapy (IMRT) in locally advanced nasopharyngeal carcinoma (NPC). Methods: 160 patients with locally advanced NPC were randomly divided into a chrono group and conventional group according to random number table. In the first stage, all patients underwent two cycles of induced chemotherapy, consisting of docetaxel, cisplatin and 5-Fu every 21 days. Notably, patients received chrono-moduated chemotherapy according to circadian rhythm in the chrono group, and conventional chemotherapy in the conventional group. Then, 21 days after the completion of first stage, three cycles of concurrent cisplatin chemotherapy every 21 days were given to all patients during IMRT. The median follow-up after the completion of radiotherapy was 31 months. Long-term side effects and the survival of patients were observed. Results: Patients in the chrono group had significantly lower rates of hearing loss (22.72%), dysphagia (0) and neck fibrosis (4.54%) compared with those in the conventional group (39.13%、8.69%, 15.94%, respectively, all P<0.05). Meanwhile, the 1- year overall survival rates (97.0% vs 92.8%), 3-year overall survival rates (80.3% vs 81.2%), 1-year progression free survival rates (95.5% vs 87.0%), 3-year progression free survival rates (71.2% vs 73.9%), 1-year locoregional relapse-free survival rates (97.0% vs 95.7%), 1-year locoregional relapse-free survival rates (92.4% vs 92.8%), 1-year distant metastasis-free survival rates (97.0% vs 98.6%) and 3-year distant metastasis-free survival rates (90.9% vs 91.3%) between the chrono group and the conventional group were not statistically significant (all P>0.05). Conclusions Compared with conventional chemotherapy, chrono-chemotherapy combined with IMRT didn′t affect long-term survival, but reducing the incidence of adverse events in patients with locally advanced NPC.

Objective: To compare the adverse events, immune status, and short-term efficacy between chronomodulated chemotherapy (CCR) and routine chemotherapy (RCR) combined with intensity modulated radiotherapy (IMRT)in the treatment of patients with locally advanced nasopharyngeal carcinoma. Methods: A total of 159 patients with newly diagnosed locally advanced nasopharyngeal carcinoma were randomized into the CCR group and the RCR group to evaluate the short-term efficacy and adverse events. Results: No significant difference was found in CR, PR, SD, and PD between the CCR group and the RCR group (P>0.05), and no significant difference was observed in the response rate (CR+ PR) between the two groups (P>0.05). The incidence of leukopenia(Z=-2.222, P<0.05), neutropenia(Z=-1.999, P<0.05), vomiting(Z=-2.298, P<0.05), and oral mucositis(Z=-3.571, P<0.05)of the CCR group was lower than those of the RCR group with statistical significance. The CD16+ 56+ lymphocyte cell count was higher in the CCR group than that in the RCR group(Z=-2.332, P<0.05). Conclusions As a novel invention, CCR combined with IMRT can reduce the incidence and severity of treatment-related adverse events and improve immune status without diminishing clinical efficacy, therefore deserving clinical application.

Objective To evaluate the differences of toxicities,therapeutic efficacy and immune function between induction chemotherapy followed by sinusoidal chrono-modulated infusion and flat intermittent infusion of cisplatin (DDP)with intensity-modulated radiotherapy (IMRT) in patients with locoregionally advanced nasopharyngeal carcinoma (NPC).Methods Seventy patients with biopsydiagnosed stages Ⅲ and Ⅳ B NPC (according to the 2010 UICC staging system) were treated with two-cycle induction chemotherapy before chemoradiotherapy in Guizhou Cancer Hospital.The TPF chemotherapy regimen was administered as follows:The TXT and DDP with the dose of 75 mg/m2 was carried out by bolus infusing for the first day,the 5-FU with 750 mg · m-2 · d-1 was carried out by continuous intravenous pumping for the first day to fifth day(120 h).The induction chemotherapy was 21 days per cycle,for two cycles.After that all patients were randomly treated with 2-3 cycles of sinusoidal chronomodulated infusion or flat intermittent constant rate infusion of DDP with IMRT.Using a multi-channel programmed pump,the patients were given 12 h continuous infusions of DDP (100 mg/m2) for day one,repeated every 3 weeks for 2-3 cycles.DDP was administered from 10:00 am to 10:00 pm.Concurrent radiotherapy regimen was administered as follows:GTVnx 69.96-73.92 Gy/33 f,PTVnx 69.96 Gy/33 f,PTVnd 69.96 Gy/33 f,PTV1 60.06 Gy/33 f,PTV2 50.96 Gy/28 f.Results The main toxicities of chemoradiotherapy in the group of sinusoidal chrono-modulated infusion were bone marrow suppression:leukocytes,and then nausea,oral mucositis and hemoglobin.The main toxicities of chemoradiotherapy in the group of flat intermittent constant rate infusion were bone marrow suppression:hemoglobin,leukocytes,and then nausea,oral mucositis.No significant differences were observed for toxicities(P ＞ 0.05).After concurrent chemoradiotherapy,the complete response rate (CR),partial response rate (PR),stable disease rate(SD),progressive disease rate (PD) and overall response rate (ORR) were 11.4％,85.7％,2.9％,0 and 97.1％ in the group of sinusoidal chrono-modulated infusion.The CR,PR,SD,PD,ORR in the group of flat intermittent constant rate infusion were 22.9％,74.2％,2.9％,0,97.1％,respectively.However,there was no significant differences of effect in the two Arms (P ＞ 0.05).For sinusoidal ehrono-modulated infusion and flat intermittent infusion group,the 2-year overall survival(OS) were 82.9％ and 94.3％ respectively,the 2-year progression-free survival(PFS) were 77.1％,91.4％ respectively,and the 2-year distant metastasis free survival (DMFS) were 82.9％,91.4％ respectively.The value of CD3 + in the group of sinusoidal chrono-modulated infusion was higher than the group of flat intermittent constant rate infusion after therapy (Z =3.254,P ＜ 0.05).The value of CD4 +,CD8 +,CD16 + CD56 +,CD19 +,and CD4 +/CD8 + had no differences in two Arms (P ＞ 0.05).Conclusions No significance differences on the toxicities,therapeutic efficacy and survival were observed between the two groups,but immune function might be improved in the sinusoidal chrono-modulated infusion group.

Objective To study the clinical characteristics, diagnosis, treatment and prognosis of primary pulmonary peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS). Methods Two cases of primary pulmonary PTCL-NOS were studied and relevant literature were reviewed. Results Case 1 diagnosed as primary pulmonary PTCL-NOS was a 44 years old woman and disease progressed after GLD (Gem+L-OHP+ DXM) chemotherapy regimen. At last, the patient died of respiratory failure after one month. Case 2 diagnosed as primary pulmonary PTCL-NOS was a 46 years old man and reach partial response after CHOP regimen, and still alive now.Conclusion Primary pulmonary PTCL-NOS is very rare. It is easy to be misdiagnosed due to non-specific clinical and imaging manifestations. Acquiring enough tissue specimens for pathologic examination is the key to a definitive diagnosis. At present, there is no standard chemotherapy regimen for these patients, the prognosis is relatively poor.

OBJECTIVE: To verify the relationship between THI and VAS scores in patients with sudden hearing loss and tinnitus in a prospective study. METHOD: Forty-four patients classified their tinnitus according to VAS and THI before and after treatment, and both scores were compared through the Pearson's correlation coefficient test and Nonparametric tests. RESULT: There was a correlation between VAS and THI scores in patients with sudden hearing loss and tinnitus. Tinnitus assessment scores were significantly reduced after treatment. Decreasing of THI and VAS scores were not depended on frequency and loudness of tinnitus and severity of deafness, but therapeutic effect of sudden sensorineural hearing loss. CONCLUSION THI and VAS scores are useful for assessment of tinnitus in patients with sudden hearing loss and tinnitus.
Audiometry ; Deafness ; Hearing Loss, Sensorineural ; complications ; Hearing Loss, Sudden ; complications ; Humans ; Prospective Studies ; Tinnitus ; complications

Objective To derive a questionnaire to assess the risk of developing motor complications through a 3-year prospective investigation on 71 patients of Parkinson' s disease (PD) in the out clinic at our hospital.Methods Three years after the first assessment,71 PD out patients were reassessed using various scales,including Unified Parkinson Disease Rating Scale,Hoehn-Yahr grade,Mini Mental State Exam,Hamilton Depression Scale and Hamilton Anxiety Scale.Results The incidence of motor complications was 43.6％ (31/71).Logistic regression analysis showed that the prognostic factors for motor fluctuation were age of onset ≤ 54 (OR =6.4,95％ CI 1.7-24.5,P =0.006),the occurrence of swallowing difficulty (OR =3.8,95 ％ CI 1.0-14.1,P =0.04) and depression (OR =4.0,95 ％ CI 1.1-13.7,P =0.03),and the prognostic factors for dyskinesia were age of onset ≤54 (OR =48.5,95％ CI 1.9-121.0,P:0.02),the occurrence of falling (OR =64.1,95％ CI 2.9-142.2,P =0.008) and the daily levodopa dosage ＞ 600 mg(OR =17.5,95％ CI 1.1-276.2,P =0.04).Based on the regression model,the assessment questionnaire for motor complicationsincludes the followings:the questionnaire for motor fluctuations:the age of onset ≤54,2 points; the occurrence of swallowing difficulty,1 point; the occurrence of depression,1 point; the questionnaire for dyskinesia:the onset age ≤54,2 points; the occurrence of falling,3 points; daily levodopa dosage ＞ 600 mg,2 points.In all patients in this study,21.7％ (10/46) was asscssed to a total scorc of 0-1 which is associated with a low risk of motor fluctuation,8/16 had a score of 2 which is associated with intermediate risk and 8/9 got a score of 3-4 associated high risk; 10.2％ (5/49) had a score of 0-2,a low risk of dyskinesia,4/13 had a score of 3-4,a intermediate risk and 7/9 got a score of 5-7 which is associated with a high risk.Conclusions Age onset ≤54,the occurrence of swallowing difficulty,falling and depression,daily levodopa dosage ＞ 600 mg were considered to be the prognostic factors of motor complications in PD.The questionnaire may help to stratify PD patients into low-risk,medium-risk and high-risk groups for motor complications and the higher the score in the questionnaire is related to the higher risk of motor complications.

Objective To investigate the dosimetric influence of pure carbon fiber treatment tabletop of Elekta Precise new linear accelerator in radiotherapy.Methods Surface-axis distance (SAD) technology was employed for the measurement.Two groups of fields were set and both of them were SAD opposed portals ( one of them went through the tabletop,while the other did not).A PTW electrometer and a 0.6 cm3 Farmer ionization chamber were utilized for comparison measurement.Then dose attenuation of the main table board,extended body board,the extended board for head,neck and shoulders,and the joints of these boards were calculated.Results Under the energy of 6 MV,the dose attenuations of the following locations were:1.4％ - 7.2％ at the main treatment table board; 2.8％ - 38.7％,1.4％ -30.1％,1.5％ -20.8％ and 1.4％ - 11.2％,respectively at distances of 1,4,7 and 8 cm from the joint of the main table board ;0.5％ - 5.0％ at the extended body board; 4.7％ - 15.4％ at distance of 1cm from the joint of the extended body board; 0.5％ -3.3％ at the neck position of the extended board for head,neck and shoulders; 5.3％ - 16.7％ at the shoulder positions; and 6.8％ -30.4％ at the joint between the extended boards and the main table board.Conclusions The dose attenuations of the new linear accelerator pure carbon fiber treatment tabletop vary at different locations. Considerable higher attenuations are observed at the table board joints than other locations.

ObjectiveThis study evaluates the feasibility of intensity-modulated radiation therapy (IMRT) to treat patients with 1 -5 brain metastases from non-small cell lung cancer (NSCLC).Methods 30 IMRT patients with brain metastases for NSCLC studied retrospectively.Whole brain radiotherapy plus three-dimensional conformal radiotherapy (WBRT + 3DCRT) and WBRT plus stereotactic radiotherapy ( WBRT + SRT) plans were generated.Planning target volume ( PTV ) and organs at risk dose were measured and compared by dose volume histogram.Differences were analyzed in the three techniques by Wilcoxon Z -test.Results D99％ of the shoulder ( D99％-D90％ ) from IMRT were higher than from WBRT +3DCRT and WBRT+SRT in all cases.From D15％ of slope (D90％-D10％) to D5％ of tail (D10％ -D1％ ),IMRT were lower than WBRT + 3DCRT and WBRT + SRT ( Z =- 4.72,P =0.000 and Z =- 4.72,P =0.000).D10％ and D5％ of IMRT were (35.1 ±1.42) Gy and (37.7 ±2.91) Gy,WBRT +3DCRT were (36.5±2.86) Gy and ( 39.1 ± 3.56) Gy ;WBRT + SRT were (36.2 ± 2.57) Gy and ( 38.7 ± 3.67) Gy.IMRT vs WBRT+ 3DCRT and WBRT + SRT were significant ( Z=-3.18,-3.18,P=0.001,0.001 and Z=- 4.11,- 3.02,P =0.000,0.002) in 13 patients with 3 - 5 brain metastases.The total mean monitor units were 14756.3,9614.8 and 9043.2 for IMRT,WBRT +3DCRT and WBRT + SRT plans,respectively,with a 38.7％ reduction from IMRT to WBRT + SRT (Z =-4.78,-4.78,P =0.000,0.000).The brain doses around metastases were similar in the three techniques with 1 -2 metastases,but IMRT was the best with 3 -5 metastases.ConclusionsIMRT can advance brain metastases dose and improve the planning target minimum dose and spare the dose around brain metastases.Only IMRT is the best choice for just sparing the dose around brain metastases among 3 -5 brain metastases.