Objective:To evaluate whether comprehensive salivary gland-sparing helical tomotherapy (HT) can reduce radiation-induced xerostomia without compromising locoregional control or survival in patients with nasopharyngeal carcinoma (NPC). Methods:A total of 266 patients with NPC treated with HT were prospectively analyzed. A comprehensive salivary gland-sparing planning strategy, including preservation of the parotid glands and other salivary structures whenever clinically feasible, was applied to minimize irradiation of salivary glands. Xerostomia was assessed using patient-reported outcome measures during follow-up. Acute and late toxicities were graded according to the RTOG/EORTC criteria. Overall survival (OS), cancer-specific survival (CSS), locoregional recurrence-free survival (LRRFS), and distant metastasis-free survival (DMFS) were estimated using the Kaplan-Meier method. Results:With a median follow-up of 70.5 months, patients showed significant improvement in xerostomia symptoms. Late xerostomia was observed in 26 patients (9.8%) with Grade I-II, and only one patient (0.4%) developed Grade III xerostomia. The 1-, 3-, and 5-year overall survival (OS) rates were 95.9%, 86.8%, and 81.6%, respectively, while the corresponding cancer-specific survival (CSS) rates were 98.1%, 92.6%, and 90.2%. Locoregional control remained excellent, with a locoregional recurrence rate of 7.5% and a 5-year locoregional recurrence-free survival (LRRFS) of 92.1%. No grade 4 acute or late toxicity was observed. Multivariate Cox regression analysis demonstrated that age was significantly associated with survival outcomes (OS: p = 0.01; CSS: p = 0.01). Conclusions:Comprehensive salivary gland-sparing helical tomotherapy reduces radiation-induced xerostomia without compromising locoregional control or survival, supporting its oncologic safety in NPC radiotherapy. Clinical trial registration:https://www.chictr.org.cn/showproj.html?proj=17360, identifier ChiCTR-ONN-17010597.

Background:With the development of various advanced radiotherapy techniques, research related to radiotherapy for bone metastases has made great progress, and scholars have published a large number of publications. In this study, we summarized the knowledge structure of radiotherapy for bone metastases and outlined the research hotspots through bibliometric analysis. Methods:Publications on radiotherapy for bone metastases from 1992 to 2024 were searched in the Web of Science Core Collection (WoSCC) database. Countries, institutions, authors, references, and keywords in the field were visualized using VOSviewer version 1.6.19 and CiteSpace version 6.3.R1. Results:1303 publications from 71 countries were included in this study. The number of research publications on radiotherapy for bone metastases has been increasing year by year. The United States of America (USA) ranking first in terms of publication count and co-citation frequency. The most prolific institutions and authors were the University of Toronto and Sahgal A, while Chow E was the most co-cited author. The most co-cited paper was published by Lutz S et al. in 2011 in Internation Journal Of Radiation Oncology Physics. "stereotactic body radiotherapy", "spine metastases", "spinal cord compression", " immunotherapy" and "oligometastases" are the main keywords of the current research topics. Conclusions:The application of stereotactic body radiotherapy (SBRT) in the treatment of patients with bone metastases, especially oligometastases, has attracted extensive attention from researchers. How to choose reasonable radiotherapy for patients with complicated bone metastases has now become a research hotspot. Radiotherapy combined with immunotherapy may be the future development trend.

The present study aimed to assess the impact of chest radiotherapy combined with immunotherapy at different time points in lung injury. This retrospective study analyzed 35 patients with thoracic tumors (29 lung cancer cases and 6 esophageal cancer cases) who received radiotherapy combined with immunotherapy between January 2021 and December 2023 at at Capital Medical University, affiliated with Beijing Luhe Hospital (Beijing, China), with a median follow-up time of 21 months. Patients were divided into two groups: Group A (sequential, n=17), who received immunotherapy 2 weeks to 6 months before or after radiotherapy, and group B (synchronous, n=18), who received immunotherapy within 2 weeks before or after radiotherapy. Furthermore, the incidence and severity of lung injury, especially pneumonitis, were also compared. Moreover, risk factors for lung injury, as well as 3-year overall survival (OS) rates for stage III and IV lung cancer, were evaluated. There were no significant differences in tumor location, stage, age, tumor type, Eastern Cooperative Oncology Group score or sex between groups. The proportion of PD-1 in group A was higher, while the proportion of PD-L1 was lower, compared with that in group B. Furthermore, radiotherapy techniques and dosimetric parameters were also similar. Moreover, there were no significant differences in onset time between esophagitis, anemia or pneumonitis between the two groups. However, incidence of grade 3 or higher pneumonitis was 0.0% in the sequential group and 23.5% in the synchronous group, which was significantly different. Univariate analysis identified lung mean dose and the percentage volume receiving ≥30 Gy (V30) as significant risk factors, whereas multivariate analysis revealed that V30 was an independent prognostic factor. The 3-year OS rates for stage III and IV lung cancer were 44.8 and 22.5%, respectively. In conclusion, the present study revealed that radiotherapy combined with immunotherapy increases the survival rate; however, it also elevates the risk of grade 3+ pneumonitis, especially within 2 weeks of concurrent therapy. As pneumonia occurs at around 3 months after radiotherapy, a follow-up time of 2-4 months post-treatment is recommended.

ObjectiveThis study aims to assess the impact of preoperative synchronized lateral lymph node simultaneous integrated boost radiation therapy on the prognosis of T3-4N+ rectal cancer patients.MethodsA retrospective analysis was performed on 35 patients with rectal cancer from Beijing Luhe Hospital affiliated to Capital Medical University from August 1, 2019 to April 30, 2023, including 22 patients with T3-4N+ rectal cancer, all of whom received the above preoperative therapy: planning gross tumor volume (PGTV): 95% PGTV 55 Gy/2.2 Gy/25 times; planning gross tumor volume of node (PGTVnd): 95% PGTVnd 60 Gy/2.4 Gy/25 times; and planning target volume (PTV): 95% PTV 50 Gy/2 Gy/25 times. Total mesorectal excision (TME) was performed 8-12 weeks after the radiotherapy. The primary endpoints were postoperative pathologic complete response (pCR) rate, downstaging rate, and 1-, 2-, and 3-year local regional recurrence-free survival (LRRFS). The secondary endpoints were anal retention rate, 1-, 2-, and 3-year event-free survival (EFS), overall survival (OS) rates, treatment-emergent adverse events (TEAEs), and perioperative complications.ResultsAll 22 patients completed treatment, with pCR rate of 22.7% (5/22), anal preservation rate of 77.3% (17/22), tumor downstaging (T-downstaging) rate of 95.5% (21/22), and nodal downstaging (N-downstaging) rate of 100% (22/22), and 1-year postoperative LRRFS, EFS, and OS rates of 100%, 80%, and 86%, respectively; 2-year LRRFS, EFS, and OS rates of 90%, 63%, and 75%, respectively; and 3-year LRRFS, EFS, and OS rates of 90%, 63%, and 63%, respectively. Only two cases of Grade 3 adverse events occurred, which were clinically manageable and did not require permanent treatment cessation.ConclusionThis retrospective analysis demonstrated encouraging short-term outcomes, including a 22.7% pCR rate and a 3-year LRRFS of 90%, with manageable toxicity. Nonetheless, these findings should be interpreted with caution due to the limited sample size and absence of a control arm.

The albumin-to-creatinine ratio (ACR) is known to predict prognosis in liposarcoma patients, but its role in other tumors remains unclear. This study aimed to evaluate the prognostic relationship between ACR and common solid tumors. Data from the Investigation on Nutrition Status and Clinical Outcome of Common Cancers (INSCOC) between 2013 and 2022 were used to analyze patients under 65 years old with solid tumors. Patients were divided into a training cohort (n = 12,027) and a validation cohort (n = 7,985) using simple random sampling. Correlation analysis, Kaplan–Meier method, and restricted cubic spline analysis were conducted to explore ACR's relationship with overall survival (OS). Multivariable logistic regression assessed associations between ACR and Patient—Generated Subjective Global Assessment (PG-SGA), Length of Stay (LOS), and Karnofsky Performance Status (KPS). In Cox regression, higher ACR levels were associated with better OS in solid tumor patients. Specifically, when using the cutoff value with low ACR as the reference, higher ACR levels were significantly associated with improved OS. For nasopharyngeal carcinoma (HR = 0.49, 95

BackgroundThe Hemoglobin, Albumin, Lymphocyte, and Platelet score (HALP) is an inflammatory nutrition-related biomarker based on hemoglobin and albumin levels, as well as the lymphocyte and platelet load index, which has been reported to be associated with the prognosis of various types of tumors. This study aims to investigate the prognostic value of HALP in patients with non-small cell lung cancer (NSCLC).MethodsA total of 2,428 patients with NSCLC were enrolled in the INSCOC study. Time-patient survival trends were validated using Kaplan–Meier curves and log-rank tests. The Restricted Cubic Spline function was used to analyze the relationship between the HALP index and overall survival (OS). The Cox regression model was used for univariate and multivariate analyses.ResultsThe study included 2,053 patients with detailed biological information and follow-up data, consisting of 1,346 men (65.6%) and 707 women (34.4%). Within this cohort, 138 patients (6.7%) had stage I disease, 282 (13.7%) had stage II, 477 (23.2%) had stage III, and 1,156 (56.3%) had stage IV. A total of 536 patients (26.1%) underwent surgery, 1,494 (72.8%) received chemotherapy, and 271 (13.2%) received radiotherapy. The 1-, 2-, 3-, and 5-year survival rates for patients with NSCLC were 68.6, 48.6, 37.4, and 30.9%, respectively. The optimal cut-off for HALP was determined to be 29.71, with a sensitivity of 53.1% and specificity of 62.9%, leading to the categorization of patients into low (<29.71) (n = 963) and high (≥29.71) (n = 1,090) HALP groups. Patients with a high HALP demonstrated a significantly higher 5-year overall survival (OS) rate compared to those with a low HALP (38% vs. 23%, p < 0.001). Multivariable Cox proportional hazards regression analysis identified that low HALP was an independent risk factor for the survival of patients with non-small cell lung cancer.ConclusionThe HALP index can be used as an independent prognostic factor for patients with NSCLC, offering clinicians a reference to identify high-risk patient with poor long-term prognoses and improve individualized treatment.

The present report describes a case of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) with pericardial invasion following bone marrow transplantation. The patient exhibited recurrent pericardial effusion accompanied by wheezing symptoms. Despite undergoing multiple pericardial punctures and drainage procedures, pericardial injections, and systemic treatment, the patient continued to experience recurrent pericardial effusion. Ultimately, the patient underwent whole-heart radiotherapy, resulting in complete resolution of the pericardial effusion. After a follow-up period of 10 months, the pericardial effusion remained well-controlled, and there were no significant impairments in cardiac function. In conclusion, radiotherapy may be considered as a viable treatment option for refractory leukemia cases presenting with pericardial effusion.

背景 放射治疗是直肠癌主要治疗手段之一,国内放疗设备种类繁多、层次不一,基层医院放疗设备落后,大多以国产放疗设备为主.目的 探讨国产与进口精确放疗设备在直肠癌术后放疗中的临床剂量学特点与治疗实施效率,为临床应用提供选择依据.方法 从解放军总医院第一医学中心放射治疗科 2017年 7-10月治疗患者中选取 10例局部进展期直肠癌根治术后放疗患者资料,分别采用国产加速器(A组)和进口加速器(B组)进行放疗计划设计和验证比较.通过剂量体积直方图对靶区及危及器官进行剂量统计,根据相应公式计算靶区适形指数(conformity index,CI)与均匀指数(homogeneity index,HI),最后统计机器治疗时间和跳数.应用配对t检验进行统计学分析.结果 国产与进口精确放疗设备的治疗计划均能满足靶区处方剂量及危及器官限量要求.两组计划中,B组靶区的D2％、D5％、D98％、CI和HI优于A组(P＜0.05),但两组的D95％无统计学差异.在正常器官保护上,两组的小肠V30、双侧股骨头V40 无统计学差异,而A组膀胱的V40 优于B组(P＜0.05).两组计划通过率无统计学差异,在计划实施效率上A组略优于B组(P＜0.05).结论 国产与进口精确放疗设备均能实现直肠癌术后调强放疗的靶区剂量分布要求,剂量学上安全可行,各级别医院可根据临床需求进行选择应用.

Background To evaluate the long-term survival and treatment-related toxicities of helical tomotherapy (HT) in nasopharyngeal carcinoma (NPC) patients. Methods One hundred and ninety newly diagnosed non-metastatic NPC patients treated with HT from September 2007 to August 2012 were analyzed retrospectively. The dose at D95 prescribed was 70-74Gy, 60-62.7Gy and 52-56Gy delivered in 33 fractions to the primary gross tumor volume (pGTVnx) and positive lymph nodes (pGTVnd), the high risk planning target volume (PTV1), and the low risk planning target volume (PTV2), respectively, using simultaneous integrated boost technique. The statistical analyses were performed and late toxicities were evaluated and scored according to the Common Terminology Criteria for Adverse Events (version 3.0). Results The median follow-up time was 145 months. The 10-year local relapse-free survival (LRFS), nodal relapse-free survival (NRFS), distant metastasis-free survival (DMFS) and overall survival (OS) were 94%, 95%, 86%, and 77.8%; respectively. Fifty (26.3%) patients had treatment-related failures at the last follow-up visit. Distant metastasis, occurred in 25 patients, was the major failure pattern. Multivariate analysis showed that age and T stage were independent predictors of DMFS and OS, Concomitant chemotherapy improved overall survival, but anti-EGFR monoclonal antibody therapy failed. The most common late toxicities were mainly graded as 1 or 2. Conclusions Helical tomotherapy with simultaneous integrated boost technique offered excellent long-term outcomes for NPC patients, with mild late treatment-related toxicities. Age and clinical stage were independent predictors of DMFS and OS. And, concurrent chemotherapy means better OS. Further prospective study is needed to confirm the superiority of this technology and to evaluate the roles of anti-EGFR monoclonal antibody treatment.

Objective:To evaluate the efficacy of preoperative neoadjuvant chemoradiotherapy for low and locally advanced rectal cancer.Methods:Clinical data of 46 patients with low rectal tumors located within 6 cm from the edge of anal admitted to our hospital between February 2014 and December 2018 were retrospectively analyzed. SIB-IMRT technique was adopted for preoperative radiotherapy. Rectal tumors and positive lymph nodes were irradiated with a dose of 58.75 Gy in 25 fractions (2.35 Gy/fraction), and pelvic lymphatic drainage area was given with 50 Gy in 25 fractions (2.0 Gy/fraction). Oral administration of capecitabine was delivered for concurrent chemotherapy. Radical surgery for rectal cancer was performed at 6 to 12 weeks after the end of chemoradiotherapy. The overall survival (OS), disease-free survival (DFS), progression-free survival (PFS), local recurrence-free survival (LRFS) and metastasis-free survival (MFS) were calculated by using Kaplan- Meier method. Univariate analysis was conducted by log-rank test, and multivariate analysis was performed by Cox’s regression model. Results:After a median follow-up of 47 months, local recurrence occurred in 3 patients and distant metastasis in 6 patients. The ypCR rate was 26%(12/46), the sphincter-preservation rate was 74%(34/46), the R 0 resection rate was 100%(44/44), the overall tumor response TN down staging rate was 87%(40/46), and the postoperative complication rate was 13%(6/46). The 3-year OS, DFS, and PFS were 93%, 91% and 87%, respectively. In univariate analysis, ypN staging was an important factor affecting OS, DFS, PFS, LRFS and MFS (all P<0.05). In multivariate analysis, ypN staging was significantly correlated with DFS, PFS, LRFS and MFS (all P<0.05). Conclusions:Preoperative SIB-IMRT 58.75 Gy in 25 fractions combined with capecitabine chemotherapy is a safe and efficacious treatment for patients with low and locally advanced rectal cancer, which improves the ypCR rate and quality of life, and yields tolerable adverse reactions. Nevertheless, the long-term survival benefits remain to be validated.

目的 观察中低位局部进展期直肠癌患者术前同期加量调强放疗联合希罗达化疗的临床可行性、安全性及疗效.方法 解放军总医院第一医学中心放疗科于2012年2月-2013年5月入组19例临床诊断为cT2-3N+M0直肠腺癌患者,行新辅助同期加量调强放疗(simultaneous integrated boost intensity-modulated radiation therapy,SIB-IMRT)联合希罗达同步化疗.放疗剂量分割模式:直肠原发肿瘤及盆腔转移淋巴结(pGTV)照射56.25 Gy/25次(2.25 Gy/次),高危复发区域和区域淋巴引流区(PTV)照射50 Gy/25次(2.0 Gy/次).希罗达用量为825 mg/m2,2次/d,5 d/周,共5周.放化疗结束后6～10周行全直肠系膜切除术(total mesorectal excision,TME).研究主要结局指标为病理完全缓解率、保肛率,及3年、5年、7年的总生存(overall survival,OS)、局部复发率(local recurrence rate,LRR)、远处转移率(distant metastasis rate,DMR)、无病生存(disease-free survival,DFS).次要结局指标为急性期及晚期不良反应、TN降期率、围术期并发症.结果 19例患者中位年龄为57(34～70)岁,其中女性3例,男性16例.19例均完成同步放化疗及TME手术,早、晚期不良反应均为1～2级,未见3～4级严重不良反应.病理完全缓解率21.1％(4/19),保肛率73.7％(14/19),R0切除率100％,TN降期率66.7％(20/30).围术期并发症发生率15.8％(3/19),分别为粘连性肠梗阻、结扎线脱落、直肠阴道瘘各1例.3年OS、LRR、DMR、DFS分别为94.4％(17/18)、5.1％(1/18)、0、94.4％(17/18);5年OS、LRR、DMR、DFS分别为88.2％(15/17)、10.5％(2/17)、5.3％(1/17)、88.2％(15/17);7年OS、LRR、DMR、DFS分别为82.3％(14/17)、15.8％(3/17)、10.5％(2/17)、82.3％(14/17).结论 局部进展期中低位可手术切除直肠癌行术前SIB-IMRT联合化疗,获得较满意的病理完全缓解率、保肛率及3年、5年、7年OS、LRR、DMR、DFS,未见3～4级不良反应,耐受性好,未增加围术期并发症发生率,安全可行.

The aim of this study was to evaluate the safety and clinical efficacy of a combined preoperative regimen consisting of volumetric modulated arc therapy-simultaneous integrated boost and capecitabine chemotherapy for distal rectal cancer. A total of 26 patients with locally advanced distal rectal cancer were enrolled from March 2015 to May 2016. The radiation dose fractionation was 58.75 Gy/25 fractions (2.35 Gy/fraction) for rectal tumor and pelvic lymph node metastasis and 50 Gy/25 fractions for pelvic lymph node stations, accompanied with simultaneous capecitabine chemotherapy. Completion of the simultaneous chemotherapy was ensued by 1 week of rest and then another cycle of induction chemotherapy with capecitabine. A radical rectal cancer surgery was performed 6 to 8 weeks after the simultaneous chemoradiotherapy. The primary end points were the complete pathological response rate and the postoperative sphincter preservation rate. All 26 patients completed the neoadjuvant chemoradiotherapy, among which 25 received surgical treatment. The postoperative complete pathological response rate was as high as 32% (8/25), while the sphincter preservation rate was 60% (15/25), the overall tumor/node (T/N) downstaging rate was 92% (23/25), and the R0 resection rate was 100%. During the chemoradiation, the most common adverse events were grade 1 and 2; grade 3 radiodermatitis occurred in 2 cases but no occurrence of acute adverse events occurred that were grade 4 and above. After the surgery, there was one case of ureteral injury and one case of intestinal obstruction, but no perioperative deaths occurred. In conclusion, the chemoradiation regimen of preoperative volumetric modulated arc therapy-simultaneous integrated boost (VMAT-SIB58.75Gy) and a single cycle of induction chemotherapy with capecitabine for patients with distal rectal cancer is safe and feasible with a satisfactory complete pathological response rate, sphincter preservation rate, and R0 resection rate.

Objective To evaluate the feasibility and clinical efficacy of preoperative simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) combined with neoadjuvant chemotherapy of capecitabine in patients with locally-advanced low rectal cancer.Methods Between 2015 and 2016,26 patients admitted to 301 Hospital who were diagnosed with locally-advanced low rectal cancer,which was located within 5 cm from the anal verge,were enrolled in this investigation.Dose fractionation pattern was delivered:58.75 Gy in 25 fractions (2.35 Gy/fraction) for rectal cancer and lymph node metastasis and 50 Gy in 25 fractions for the pelvic lymphatic drainage area and simultaneously combined with capecitabine chemotherapy (825 mg/m2,bid d 1-5 weekly).One cycle of capecitabine (1 250 mg/m2,twice daily,d 1-14)was given at one week after the completion of chemoradiotherapy (CRT).Total mesorectal excision (TME)was performed at 6 to 8 weeks after the completion of CRT.The primary endpoints included pathological complete response rate (ypCR) and sphincter-preserving rate.The secondary endpoints included acute toxicity,tumor downstaging rate and postoperative complications.Results Twenty-six patients successfully completed neoadjuvant CRT,25 of them underwent surgical resection and one patient failed to receive surgery due to pxrianal edema.Postoperative ypCR rate was 32％ (8/25),the sphincter-preserving rate was 60％ (15/25),the tumor downstaging rate was 92％ (23/25) and the R0 resection rate was 100％.During the period of CRT,grade 1 and 2 adverse events occurred in 24 patients,grade 3 radiation dermatitis was noted in 2 cases.No ≥ grade 4 acute adverse event was observed.Postoperative complications included ureteral injury in one case and intestinal obstruction in one patient.Conclusions Preoperative SIB-IMRT combined with neoadjuvant chemotherapy of capecitabine is a feasible and safe treatment for patients with locallyadvanced low rectal cancer,which yields expected ypCR rate,R0 resection rate and sphincter-preserving rate.Nevertheless,the long-term clinical benefits remain to be elucidated.Clinical Trial Registry Chinese Clinical Trial Registry,registration number:ChiCTR-ONC-12002387.

Objective To investigate the feasibility, safety, and short?term efficacy of preoperative capecitabine and simultaneous integrated boost intensity?modulated radiotherapy ( SIB?IMRT ) followed by one cycle of neoadjuvant capecitabine in patients with locally advanced rectal cancer ( LARC ) . Methods From March 2015 to April 2016, a total of 37 patients with LARC were enrolled in this study. They received capecitabine (825 mg/m2 orally twice daily for 5 weeks, days 1?5 weekly) and SIB?IMRT (5875 Gy in 25 fractions for rectal lesion and positive lymph nodes and 5000 Gy in 25 fractions for pelvic lymphatic drainage area) . After the concurrent chemoradiotherapy, they were allowed to rest for one week. And then they received one cycle of induction chemotherapy with capecitabine (1250 mg/m2 orally twice daily for 14 days) . And total mesorectal excision ( TME ) was scheduled at 6?8 weeks after the concurrent chemoradiotherapy. The primary endpoint was pathologic complete response ( pCR) rate, and the secondary endpoints included tumor and nodal ( TN) downstaging rate, the rate of sphincter?preserving surgery, and adverse events. Results All the 37 patients successfully received the preoperative concurrent chemoradiotherapy. Only 32 patients underwent the surgical resection, 4 patients refused surgery due to symptom relief, and 1 patient delayed surgery due to perianal edema after radiotherapy. The pCR rate was 34%(11/32);the TN downstaging rate was 91%(29/32);the R0 resection rate was 100%;24 patients ( 75%) underwent the sphincter?preserving surgery. During the period of chemoradiotherapy, most of the patients experienced grade 1/2 acute adverse events and grade 3/4 adverse events occurred in 3 patients. The postoperative complications included ureteral injury (1 patient) and intestinal obstruction (1 patient), and no death occurred in the perioperative period. Conclusions For patients with LARC, preoperative SIB?IMRT combined with one cycle of capecitabine followed by TME is safe and feasible, and has good short?term efficacy and mild acute adverse events.

Objective To explore the effectiveness of helical tomography on locally advanced pancreatic cancer (LAPC), and analyze its prognostic factors. Methods Clinical data of 20 patients (13 males, 7 females; Md age of 56 years) with locally advanced pancreatic cancer who underwent helical tomotherapy without surgery were retrospectively reviewed from Jan. 2012 to Dec. 2015 in our hospital. The short-term effectiveness and long-term survival were observed. Kaplan Meier analysis and Cox regression model were used for univariate and multivariate analysis to determine the prognostic factors. Results Proportions of malignancies located in head of pancreas and body/tail of pancreas were 62.5% and 37.5% respectively (P < 0.05). CA 19-9 levels in 53.8% of patients decreased after treatment. The pain relief rate was 72.7% (8/11). The one-year survival rates and 2-year survival rates were 40%and 10%. Multivariate analysis indicated that tumor location and Karnofsky performance status (KPS) were independent predictors for overall survival. Grade Ⅲ hematologic toxicity occured in one case and no grade Ⅲ or Ⅳ gastrointestinal toxicity occurred. Conclusion Helical tomotherapy is an effective treatment for locally advanced pancreatic cancer with less toxicity. Our study shows that the head and body/tail of the pancreas probably has different radiotherapy sensitivity, but this conclusion need to be further confirmed

Objective To analyze the set-up errors of preoperative intensity modulated radiation therapy (IMRT) in locally advanced rectal cancer and its impact factors, and provide important evidence to improve geometric accuracy and radiotherapy precision. Methods Fifty-five patients with locally advanced rectal cancer treated with preoperative IMRT in Chinese PLA General Hospital from 2014 to 2016 were enrolled. All CBCT images were obtained using on-board imaging system on a Varian Clinac iX linear accelerator. Automatic image registration of the CBCT to the planning CT was performed, and the set-up parameters including left/right (X), superior/inferior (Y), anterior/posterior (Z) directions and rotation (Roll) about X axis were recorded and corrected before radiotherapy implementation. Results All cases had undergone 869 CBCT scans. The average setup errors in the X, Y, Z axes and Roll were(1.50±1.95)mm, (3.05±5.09) mm, (1.42±1.88) mm and (0.8±0.10)°, respectively. The corresponding CTV-to-PTV margins in the direction of X, Y, and Z axes were 5.12 mm, 11.2 mm, 4.87 mm. There were no significant differences between the first 5 and the last 5 set-up and rotation errors (P > 0. 05). Univariate analysis showed that the setup errors of X, Y, Z directions were no significant differences in age, gender, body mass index, tumor distance from anus and tumor which received simultaneous integrated boost (SIB). Conclusion The set-up errors are greater in Y direction than those in X and Z axes during preoperative IMRT of rectal cancer in the supine position and the rotation errors are much smaller and can be omitted.

In China, most of patients with rectal cancer have been diagnosed in advanced stage, with a higher rate of local recurrence and distant metastasis. Preoperative chemoradiotherapy can improve tumor downstaging, surgical R0 resection rate and local control. However, it has not reduced the rate of distant metastatic relapse. Enhancing preoperative chemotherapy and increasing radiation doses have been reported to further reduce the local recurrence, distant metastasis rate, even to achieve a long-term survival benefit, and becomes the hotspot of research to locally advanced rectal cancer.

Objective To investigate the dosimetric feasibility of volumetric modulated arc therapy (VMAT)with a simultaneous integrated boost(SIB-VMAT58.75 Gy)for preoperative chemoradiotherapy in patients with locally advanced rectal cancer(LARC),and to provide a basis for clinical practice.Methods Nine patients with stage Ⅱ-Ⅲ rectal cancer who underwent preoperative concurrent chemoradiotherapy were involved in the study,and two plans were performed for each patient:SIB-VMAT58.75 Gy and VMAT50.00 Gy. For the SIB-VMAT58.75 Gy plan,the prescribed dose was 58.75 Gy(2.35 Gy/fraction)for the local rectal tumor and positive lymph nodes(GTV 58.75 Gy),and 50 Gy(2 Gy/fraction)for the regions at high risk of harboring microscopic disease(pelvic lymphatic drainage area)(PTV 50Gy).For the VMAT50.00 Gy plan,the prescribed dose was 50 Gy(2 Gy/fraction)for the regions at high risk of harboring microscopic disease(pelvic lymphatic drainage area)without a boost. The conformity index(CI),homogeneity index (HI),and dose for target areas and organs at risk(OAR)were assessed according to the dose-volume histogram. The paired t-test or nonparametric rank test was used to compare the differences between the two plans. Results Both plans met the prescription goal for PTV dose coverage. There was no significant difference in CI for the PTV between the two plans(1.0±0.0 vs. 1.0±0.0,P>0.05).The SIB-VMAT58.75 Gy plan had a worse HI than the VMAT50.00 Gy plan(0.2± 0.2 vs. 0.1± 0.0,P<0.05).There was no significant difference in V10-V50of the small intestine,bladder,femoral heads,and pelvis between the two plans(P>0.05),but D 2 cm3of the small intestine was significantly higher in the SIB-VMAT58.75 Gy plan than in the VMAT50.00 Gy plan(P=0.038). Conclusions The SIB-VMAT58.75 Gy plan for LARC achieves required target volume dose coverage and OAR dose constraints,which is safe and feasible in terms of dosimetry,and its clinical efficacy and adverse effects need further evaluation.