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Objective:To design a knowledge-based cervical cancer planning model and apply it to cases of endometrial cancer and rectal cancer in order to explore the generalization of the model.Methods:A total of 179 cases of pelvic regions with different prescribed doses of dual-arc volumetric modulated arc therapy clinical plans were collected, of which 99 cases of cervical cancer clinical plans with a prescribed dose of 50.4 Gy were used as the training set to establish the RapidPlan model, and the remaining clinical plans were divided into 4 validation groups with 20 cases in each group. The clinical plans for cervical cancer and endometrial cancer with a prescription dose of 50.4 Gy were named groups A and B, while the clinical plan for endometrial cancer and rectal cancer with a prescription dose of 45 Gy were named groups C and D. The model was used to redesign the clinical plans in the 4 groups and the automatic plans were obtained. The planning target volume (PTV) and organ at risk (OAR) dosimetry parameters were compared between automatic plans and clinical plans.Results:The conformity index (CI) of the automatic plans in the A, B, C, and D groups were equivalent to that of the clinical plans ( P>0.05). The homogeneity index (HI) and D2% of the automatic plans in groups A, B, and C were all lower than those in clinical plans(HI, Z=-3.248, -3.360, -2.329, P<0.05; D2%, Z=-2.987, -3.397, -2.442, P<0.05). The HI and D2% of the automatic plans in group D were similar those in the clinical plans ( P>0.05). While ensuring the PTV coverage, the average value of OAR dosimetry parameters in all automatic plans groups were lower than that of the clinical plans. Conclusions:The RapidPlan model established by the cervical cancer clinical plans can complete the automatic plan design for endometrial cancer and rectal cancer under different prescription doses, which preliminarily proves the possibility of the generalization of the RapidPlan model.
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Objective:To investigate the accuracy and feasibility of 3D-printing individualized template-guided and CT-guided 192Ir interstitial brachytherapy in the central recurrent gynecologic tumors by comparing pre-plan and intraoperative physical dosimetric parameters. Methods:This study involved 38 patients with central recurrent gynecologic tumors who underwent 3D printing individual template (3D-PIT)-assisted and CT-guided 192Ir interstitial brachytherapy in the Department of Radiation Oncology of the Peking University Third Hospital from Jan 2018 to Dec 2019.The prescription doses for the target tumor areas were 10-36 Gy to be delivered at 5-6 Gy/fraction for 2-6 fractions.The pre-plan and intraoperative dosimetric parameters were compared, including the minimum prescription doses delivered to 90% and 100% of target volume( D90, D100)and the mean percentage of volume receiving 100% of the prescription doses ( V100). Meanwhile, the doses delivered to 2 cm 3 ( D2 cm 3) of organs at risk (bladders, rectums, and colons) were analyzed.The quality parameters of the brachytherapy were studied, including conformity index (CI), homogeneity index (HI), and external index (EI) of the target volume.Perioperative complications were also observed. Results:A total of 194 treatments were included.During the treatment, 5-13 (median 6) needles were inserted, with a prescription dose of 5-6 Gy per fraction.There were no statistical differences between pre-plan and intraoperative D90, D100, V100, CI, HI, and EI as well as the D2 cm 3 of bladders and colons at risk ( P>0.05). In contrast, for the D2 cm 3 of rectums, the intraoperative dose was slightly higher than the pre-plan dose, showing a statistical difference ( t=-0.335, P=0.027). Conclusions:The 3D-PIT-assisted and CT-guided 192Ir interstitial brachytherapy at a high dose rate is accurate and feasible in the treatment of recurrent gynecologic tumors, meeting the pre-plan dose requirement.
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OBJECTIVE: To investigate the efficacy of image-guided radioactive 125I seed (IGRIS) implantation for pelvic recurrent cervical cancer (PRCC) after external beam radiotherapy (EBRT), and analyze the influence of clinical and dosimetric factors on efficacy. METHODS: From July 2005 to October 2015, 36 patients with PRCC received IGRIS. We evaluated local progression-free survival (LPFS) and overall survival (OS). RESULTS: The median follow up was 11.5 months. The 1- and 2-year LPFS rate was 34.9% and 20%, respectively. The multivariate analysis indicated recurrence site (central or pelvic wall) (hazard ratio [HR]=0.294; 95% confidence interval [CI]=0.121–0.718), lesion volume (HR=2.898; 95% CI=1.139–7.372), D 90 (HR=0.332; 95% CI=0.130–0.850) were the independent factors affecting LPFS. The 1- and 2-year OS rate was 52.0% and 19.6%, respectively. The multivariate analysis suggested pathological type (HR=9.713; 95% CI=2.136–44.176) and recurrence site (HR=0.358; 95% CI=0.136–0.940) were the independent factors affecting OS. The dosimetric parameters of 33 patients mainly included D 90 (128.5±47.4 Gy), D 100 (50.4±23.7 Gy) and V 100 (86.7%±12.9%). When D 90 ≥105 Gy or D 100 ≥55 Gy or V 100 ≥91%, LPFS was extended significantly, but no significant difference for OS. The 79.2% of 24 patients with local pain were suffering from pain downgraded after radioactive 125I seed implantation. CONCLUSION: IGRIS implantation could be a safe and effective salvage treatment for PRCC after EBRT, which could markedly release the pain. Recurrence site, tumor volume and dose were the main factors affected efficacy. Compared with central recurrence, it was more suitable for patients with pelvic wall recurrent cervical cancer after EBRT.
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Humans , Brachytherapy , Disease-Free Survival , Follow-Up Studies , Multivariate Analysis , Radiometry , Radiotherapy , Radiotherapy, Image-Guided , Recurrence , Salvage Therapy , Tumor Burden , Uterine Cervical NeoplasmsABSTRACT
Objective To compare the differences of gross tumor volume (GTV) and dose distribution between MRI-CT fusion imaging and CT-based imaging and investigate the dose difference in the therapeutic regime.Methods Ten patients diagnosed with primary tumors of the cervical vertebra between 2013 and 2014 were enrolled.Prior to radiotherapy,the imaging data of MRI examination (GE Discovery MR 750 3.0T) were collected,transfered into the Eclipse system and subject to fusion with CT images.GTV delineation,organ at risk (OAR) delineation and dose distribution discrepancy induced by target volume differences were analyzed and statistically compared between the MRI-CT fusion and CT-based images.GTV delineation and dose parameters among different radiologists between two approches were analyzed by analysis of variance (ANOVA) and paired t-test.Non-normally distributed variables were analyzed by Wilcoxon rank-sum test.The reliability of intraclass correlation coefficient (ICC) was assessed.Results The GTVMRI-CT volume was larger compared with the GTVCT volume.The volume overlap index was 0.84±0.17.The cordMRI-CT volume was significantly less than the cordCT volume (P=0.001).For 5 radiologists,the ICCMRI-CT was larger than ICCCT.The DmaxMRI-CT of the spinal cord was (46.00± 1.09) Gy,significantly less than (52.39±1.34) Gy for the DmaxCT(P=0.014).Conclusions It is unlikely to miss the target delineation on MRI-CT fusion imaging.MRI-CT fusion imaging can minimize the discrepancy of interobserver radiologists and cause dosimetric advantages.
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Objective To evaluate the outcomes and prognostic factors of image-guided 125I seed implantation for locally recurrent soft tissue sarcoma(RSTS).Methods A total of 60 patients with RSTS who received image-guided 125I seed implantation in Peking University Third Hospital,from September 2002 to December 2015,were retrospectively analyzed.The enrollment criteria: KPS ＞60 points,refused or could not tolerate surgery or radiotherapy,the expecting survival time ＞3 months,relapsed after multiple treatment of soft tissue sarcoma,and underwent CT or ultrasound guided 125 I seed implantation treatment.In all,the median activity of seeds was 25.9×106Bq(range,11.1×106-29.6×106Bq),median number of implanted seeds was 58(range,3-133),and the median D90was 120 Gy(range,36.50-460.97 Gy).The local progression-free survival(LPFS)and overall survival(OS)were calculated using the Kaplan-Meier method.The log-rank test and Cox regression model were used for the univariate and multivariate analyses.Results The median follow-up was 18.75 months(range,1-146).The median OS was 18.5 months(95％CI 13.1-23.9).The 1-,3-and 5-year OS rate were 63.3％,33.0％and 29.5％,respectively.The 1-,3-and 5-year LPFS rate were 72.5％,63.7％and 59.7％,respectively.The general rate of pain relieving was 100％(6/6).8.3％(5/60)presented grade Ⅳskin toxicity.No fatal complications ocurred.The univariate analysis suggested that tumor size,tumor volume,KPS score,D90were prognostic factors of OS and LPFS.The multivariate analysis demonstrated that previous chemotherapy history and distant metastases were independent prognostic factors of survival.Conclusions Image-guided 125I seed implantation for recurrent soft tissue sarcoma is a safe treatment option with high efficacy and low morbidity.Tumor size and D90were the prognostic factors of OS and LPFS.
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Objective To evaluate the efficacy and adverse effects of 125I seeds implantation for pelvic recurrence of cervical cancer (PRCC) after radiotherapy.Methods From July 2005 to October 2015,36 PRCC patients (median 44 years) after radiotherapy in Peking University Third Hospital were enrolled in this retrospective study.All patients underwent 125I seeds implantation under ultrasound or CT guidance.Treatment planning was performed before implantation to estimate the number and activity of 125I seeds.The seed numbers ranged from 10-140 (median:62.5),and the activity ranged from 18.5-29.6 (median:25.9) MBq.Postoperatively,the median dose delivered to 90％ gross tumor volume (D90) was 127.3 Gy.Kaplan-Meier method was used to calculate local progress free survival (LPFS) rate and overall survival (OS) rate,and log rank test and Cox regression were used for univariate and multivariate analyses.Results The median follow-up time was 11.5 months.The local control rate was 88.89％(32/36).The 1-year LPFS rate was 34.9％ and the 1-year OS rate was 52.0％.Thirty-one patients died,of which 22 (70.97％,22/31) died from cancer.Univariate analysis showed that the location of recurrence (x2=5.195),volume of lesion (hazard ratio (HR)=1.012) and D90(HR=0.988) were significantly correlated with LPFS (all P＜0.05).Multivariate analysis showed that the location of the recurrence was significantly related with LPFS (HR =0.215,P＜0.05).The 1-year LPFS rates of pelvic wall recurrence and central recurrence were 41.6％ and 26.7％ (x2 =5.195,P＜0.05),and 1-year OS rates were 54.7％ and 49.5％ (x2 =2.535,P＞0.05),respectively.Vaginal fistula,which may be caused by the treatment,occurred in 1 case.No other sever adverse effects were observed.Conclusions 125I seeds implantation is a safe and effective treatment for PRCC after radiotherapy.With the treatment of 125I seeds implantation,patients with pelvic wall recurrence may achieve better therapeutic effects than those with central recurrence.
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Objective To retrospectively study the efficacy and side-effect of 125I seed implantation combined with endocrinal therapy in stage T3N0M0 prostate cancer.Methods The study included 22 patients with clinical stage T3 N0 M0 prostate cancer who were treated with transperineal 125I seed implantation guided by transrectal ultrasound,real time TPS and endocrinal therapy.The minimum peripheral doses (MPD) were 140-160 Gy.The median number of seeds was 74(26-90).The activity of each seed was 1.55 × 107 (1.30 × 107-1.85 × 107) Bq.11 patients were treated with orchidectomy,and 11 patients were treated with androgen deprivation therapy.Results All 22 patients completed the seed implantation successfully.The 5-year biochemical progression-free survival was 70.6％,and 5-year overall survival was 81.8％.2 patients were found biochemical failure in 12 months after seed implantation,and another 1 patient failed in 90 months.Endocrinal therapy was followed thereafter.After the seed implantation,the urinary complications of grade 1 and 2 were 54.5％ and 9.1％ respectively,and the rectum side-effect of grade 1 and 2 were 22.7％ and 9.1％.1 patient suffered rectal complication of grade 4.Conclusions Good effect and tolerance are observed in prostate cancer patients of stage T3N0M0 receiving 125I seed implantation plus endocrinal therapy.The treatment can be considered for those who refuse to receive external beam radiotherapy.
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Objective To summarize the efficacy and the feasibility of 125I seed implantation for recurrence cervical lymph node of head and neck tumor after radiotherapy or radiotherapy plus neck dissection. Methods Thirty-six patients with the recurrence cervical lymphnode of head and neck tumor after radiotherapy (17 patients) or radiotherapy plus neck dissection (19 patients) were treated with 125I seed implantation guided by ultrasound or CT under local anesthesia. The median number of seeds was 27( range from 3 to 78 ). Postoperative quality evaluation were routinely obtained for all patients. The actuarial D90 ranged from 90-160 Gy (median, 130 Gy). Results The follow-up rate was 100%. The number of the patients who were followed up over 1-and 2-year were 11 and 3. The overall response rate was 81%. The 1-and 2-year over local control rates, over survival rates were 69% and 35%, 50% and 22%, respectively.The 1-and 2-year local control rates in patients with recurrence node after radiotherapy plus neck dissection were 72% and 54%, while those were 67% and 50% in patients with recurrence node after radiotherapy,respectively (χ2=00,P=0.965). The 1-and 2-year survival rates in two groups were 48%, 13% , and 51%, 39%, respectively (χ2=0.17, P=0.676). Conclusions 125I seed implantation is a safe,minimal invasive with low morbidity and high efficacy salvage treatment method for cervical lymph node recurrence of head and neck tumor after radiotherapy with or without neck dissection.