三维适形放疗与调强放疗对晚期非小细胞肺癌患者血清肿瘤标志物及剂量学参数比较研究

目的:对比晚期非小细胞肺癌患者经三维适形放疗(3D-CRT)与调强放疗(IMRT)后,其血清肿瘤标志物及剂量学参数的变化。方法:选择2015年1月-2016年12月期间我院收治的非小细胞肺癌患者120例,根据放疗方案将其分为IMRT组60例与3D-CRT组60例。比较两组临床疗效、药物毒副反应、1年内的生存率、放射剂量参数,以及治疗前与治疗后血清肿瘤标志物的变化。结果:IMRT组治疗的总有效率与3D-CRT组对比差异无统计学意义(P0.05)。IMRT组血小板减少、Ⅲ度放射性食管炎、Ⅲ度消化道反应、Ⅲ度放射性肺炎、Ⅲ度白细胞减少的发生率均低于3D-CRT组(P0.05)。IMRT组1年内的生存率90.00%,高于3D-CRT组的75.00%(P0.05)。IMRT组CI值与HI值均高于3D-CRT组(P0.05),IMRT组与3D-CRT组平均剂量对比差异无统计学意义(P0.05)。治疗后两组鳞状细胞癌抗原(SCC)、细胞角蛋白19片段抗原21-1(CYFRA21-1)与肿瘤特异性生长因子(TSGF)水平均显著降低,且IMRT组低于3D-CRT组(P0.05)。结论:IMRT与3D-CRT对于晚期非小细胞肺癌患者的临床疗效相当,但IMRT药物毒副反应少、放射剂量低,可能通过控制肿瘤来降低肿瘤标志物水平。     

Comparison between intensity modulated radiotherapy (IMRT) and 3D tangential beams technique used in patients with early-stage breast cancer who received breast-conserving therapy

Background

The most often found complications in patients with breast cancer who received radiotherapy are cardiac and pulmonary function disorders and development of second malignancies.

Aim

To compare the intensity modulated radiotherapy with the 3D tangential beams technique in respect of dose distribution in target volume and critical organs they generate in patients with early-stage breast cancer who received breast-conserving therapy.

Materials and methods

A dosimetric analysis was performed to assess the three radiotherapy techniques used in each of 10 consecutive patients with early-stage breast cancer treated with breast-conserving therapy. Radiotherapy was planned with the use of all the three techniques: 3D tangential beams with electron boost, IMRT with electron boost, and intensity modulated radiotherapy with simultaneous integrated boost.

Results

The use of the IMRT techniques enables more homogenous dose distribution in target volume. The range of mean and median dose to the heart and lung was lower with the IMRT techniques in comparison to the 3D tangential beams technique. The range of mean dose to the heart amounted to 0.3–3.5 Gy for the IMRT techniques and 0.4–4.3 for the tangential beams technique. The median dose to the lung on the irradiated side amounted to 4.9–5 Gy for the IMRT techniques and 5.6 Gy for the 3D tangential beams technique.

Conclusion

The application of the IMRT techniques in radiotherapy patients with early-stage breast cancer allows to obtain more homogenous dose distribution in target volume, while permitting to reduce the dose to critical organs.     

Is IMAT the ultimate evolution of conformal radiotherapy? Dosimetric comparison of helical tomotherapy and volumetric modulated arc therapy for oropharyngeal cancer in a planning study

BackgroundIntensity Modulated Arc Therapy (IMAT) can be planned and delivered via several techniques. Advanced Radiotherapy (ARTORL) is a prospective study that aims to evaluate the treatment costs and clinical aspects of implementing these IMAT techniques for head and neck cancers. In this context, we evaluated the potential dosimetric gain of Helical Tomotherapy (TomoTherapy, Accuray, HT) versus VMAT (Rapid'Arc^®, Varian Medical System, RA) for oropharyngeal cancer (OC).Material and methodsThirty patients were selected from our database in whom bilateral neck irradiation and treatment to the primary were indicated. Each patient was planned twice using both HT and RA planning systems using a simultaneous integrated boost approach. For the planning target volumes (PTV) and organs at risk, ICRU 83 reporting guidelines were followed. RA and HT plans were compared using paired Student's t-test.ResultsRA and HT produced plans with a good coverage of PTVs and acceptable sparing of OARs. Although some dosimetric differences were statistically significant, they remained small. However, the near maximal dose to the PRV of spinal cord and brain stem was lower with HT. Regarding normal tissue, HT increased the volume irradiated at doses between 4 and 20 Gy compared to RA.ConclusionIn OC, HT and RA showed similar dosimetric results. They represent the maximum gains obtained with photon beams. The medicoeconomic evaluation of our study is ongoing and may reveal differences between these techniques in terms of MU number, fraction time, and clinical evaluation.     

SBRT and extreme hypofractionation: A new era in prostate cancer treatments?

AimRadiation therapy (RT) is a standard therapeutic option for prostate cancer (PC). In the last decades, several innovative technology applications have been introduced. 3-Dimensional conformal RT, volumetric/rotational intensity modulated RT associated or not with image-guided RT, are becoming largely diffused in the treatment of PC.BackgroundConsidering that PC could have a low α/β ratio, similar to late-reacting normal tissues, it could also be highly responsive to fraction size. Thus, the reduction of the number of fractions and the increase of the dose/fraction seem to be reasonable choices in the treatment of this cancer. This review reported the technology evolution, the radiobiological and the clinical data about the role of extreme hypofractionated RT in the treatment approach of PC patients.Materials and methodsMedline search and analysis of published studies containing key words: prostate cancer, radiotherapy, stereotactic radiotherapy.ResultsRecent technological developments, combined with an improved knowledge of the radiobiological models in favor of a high sensitivity of PC to larger fraction sizes are opening a new scenario in its treatment, reporting favorable efficacy and acceptable toxicity, despite short follow-up.ConclusionThus, thanks to technological improvement and the recent radiobiological data, “extreme hypofractionated RT” has been strongly introduced in the last years as a potential solid treatment option for PC.     

食管癌调强放射治疗的初期疗效及急性放射性肺损伤的影响因素分析

摘要 目的：探讨食管癌调强放射治疗的初期疗效及急性放射性肺损伤的影响因素。方法：选取2015年1月-2019年1月在我院进行调强放射治疗的食管癌患者322例,评价食管癌调强放射治疗后一个月的疗效;按照是否发生急性放射性肺损伤（RILI）分为急性RILI组和无急性RILI组,采用多因素Logistic回归分析分析急性RILI的影响因素。结果：调强放射治疗的完全缓解和部分缓解的患者占98.45%;322例患者中90例（27.95%）出现急性RILI,其中36例（11.18%）出现2级及以上的急性RILI;急性RILI组和无急性RILI组间卡氏（KPS）评分、淋巴结转移、基础肺疾病、V5、V10、V20、V30和全肺平均剂量（MLD）差异有统计学意义（P<0.05）;多因素Logistic回归分析显示,KPS评分<80分、有淋巴结转移、有基础肺疾病,V5≥60%、V10≥40%、V20≥28%、V30≥20%和MLD≥10Gy是食管癌调强放射治疗后急性放射性肺损伤的危险因素（P<0.05）。结论：使用调强放射治疗技术治疗食管癌的初期疗效较好,治疗过程中,应充分考虑病患的临床特征,优化放疗方案和靶区,减少急性RILI的发生,提高食管癌患者放疗后的生存质量。     

影像引导对乳腺癌调强放射治疗精度的影响

目的：分析在乳腺癌图像引导放射治疗（IGRT）过程中,图像引导对于放射治疗的精确度的影响;同时观察图像引导放射治疗的毒性反应及放射治疗近期的治疗效果。方法：搜集2012年1月-2013年2月间,于哈尔滨医科大学附属第三医院放疗科收治的乳腺癌患者25例。使用医科达SynergyTM锥形束CT（CBCT）进行治疗前扫描,通过图像引导放射治疗技术对25例患者进行误差纠正,调整后行调强放疗。患者在进行放疗前,用锥形柬CT对射野的偏差进行校正,其偏差利用锥形束CT图像与计划螺旋CT图像进行手动匹配,在X、Y、Z三个方向上进行调整。根据误差调整治疗床位置后治疗。对急性放射性反应采用RTOG5级评价标准进行评价：急性放射性皮肤反应、急性放射性肺损伤及急性放射性心脏损伤。结果：25例乳腺癌患者治疗前经锥形束CT扫描采集的图像与计划参考图像比较在X、Y、Z方向上平均误差分别为0．429±1．683mm、0．431±1．728mm、0．583±2．041mm：摆位误差纠正后,误差值分别为：0．068±0．429、0．019±0．438、0．158±0．697,调整后摆位误差控制在1mm之内进行治疗。放疗后2周急性皮肤反应为0级23例、1级2例;4周为0级21例、1级4例。无急性放射性肺损伤及心脏损伤的病例出现。结论：目前调强放疗是乳腺癌临床放射治疗的重要手段,图像引导放射治疗的应用能够使放疗精度显著提高。     

Dosimetric impact of different multileaf collimators on prostate intensity modulated treatment planning

AimThe main purpose of this study is to perform a dosimetric comparison on target volumes and organs at risks (OARs) between prostate intensity modulated treatment plans (IMRT) optimized with different multileaf collimators (MLCs).BackgroundThe use of MLCs with a small leaf width in the IMRT optimization may improve conformity around the tumor target whilst reducing the dose to normal tissues.Materials and methodsTwo linacs mounting MLCs with 5 and 10 mm leaf-width, respectively, implemented in Pinnacle³ treatment planning system were used for this work. Nineteen patients with prostate carcinoma undergoing a radiotherapy treatment were enrolled. Treatment planning with different setup arrangements (7 and 5 beams) were performed for each patient and each machine. Dose volume histograms (DVHs) cut-off points were used in the treatment planning comparison.ResultsComparable planning target volume (PTV) coverage was obtained with 7- and 5-beam configuration (both with 5 and 10 mm MLC leaf-width). The comparison of bladder and rectum DVH cut-off points for the 5-beam arrangement shows that 52.6% of the plans optimized with a larger leaf-width did not satisfy at least one of the OARs’ constraints. This percentage is reduced to 10.5% for the smaller leaf-width. If a 7-beam arrangement is used the value of 52.6% decreases to 21.1% while the value of 10.5% remains unchanged.ConclusionMLCs collimators with different widths and number of leaves lead to a comparable prostate treatment planning if a proper adjustment is made of the number of gantry angles.     

周剂量奈达铂联合调强放疗对复发鼻咽癌的近期疗效分析

目的:探讨周剂量奈达铂化疗联合调强放疗对于复发鼻咽癌患者的近期疗效及安全性.方法:将2009年2月至2012年2月本院收治的56例鼻咽癌复发患者随机分为联合治疗组与单纯放疗组,两组患者均给予适形调强放疗,联合治疗组患者在此基础上给予周剂量奈达铂化疗治疗,比较两组患者的临床疗效、并发症的发生情况及近期生存情况.结果:联合治疗组和单纯放疗组的有效率分别为78.6％和50.0％,联合治疗组有效率显著高于单纯放疗组(P＜0.05);联合治疗组白细胞减少发生率显著高于单纯放疗组(P＜0.05),其他并发症的发生率比较无显著差异(P＞o.05);联合治疗组1年、2年生存率分别为85.7％、64.3％,显著高于单纯放疗组的60.7％、42.9％(P＜0.05).结论:联合周剂量奈达铂化疗能够显著提高复发鼻咽癌患者调强放疗的临床疗效,且未增加严重并发症风险,值得临床推广应用.     

Morbidity dynamics in proton–photon or photon radiation therapy for locally advanced prostate cancer

Aim

This study evaluated the frequency and long-term dynamics of early and late post irradiation damage after proton–photon or photon therapy for locally advanced prostate cancer.

非小细胞肺癌脑部转移瘤适形与调强放疗的剂量研究

为探讨NSCLC脑部转移瘤调强放疗与适形放疗的剂量特点,本研究选取57例非小细胞肺癌脑转移瘤患者,其中单个脑转移灶患者5例,多个脑转移灶患者52例,分别设计全脑放疗+适形放疗与调强放疗计划,用均匀指数(HI)和适形指数(CI)评价靶区剂量,危及器官(OAR)剂量用近似最大剂量D_2%(串联)和中位剂量D_50%(并联)进行评价。研究发现,单个脑转移灶IMRT与WBRT+CRT比较中,CI为(PTV,(0.80±0.15) cGy,(0.34±0.19) cGy, p=0.00),HI为(PTV,(0.52±0.03) c Gy,(0.71±0.12) cGy, p=0.24),两者OARs剂量比较:脑干为((4 348±236) cGy,(4 593±149) cGy, p=0.01),脑垂体为((4 258±166) cGy,(4 581±123) cGy, p=0.02);在多个脑转移灶中,IMRT与WBRT+CRT比,较CI为(PTV,(0.59±0.33) cGy,(0.49±0.27) cGy, p=0.03),HI为(PTV,(0.93±0.01) cGy,(0.58±0.03) cGy, p=0.19),两者OARs剂量比较:脑干为((4 946±132) cGy,(4 843±196) cGy, p=0.51),脑垂体为((4 597±180) cGy,(4 705±149) cGy, p=0.70)。本研究的结果说明,单个脑转移灶患者,IMRT较WBRT+CRT有更好的靶区适形性、稍差的靶区异质性,脑干和垂体的IMRT剂量低于WBRT+CRT,而眼球、晶体的剂量两者差别不明显。多个脑转移灶患者,IMRT较WBRT+CRT有更好的靶区适形性、稍差的靶区异质性,而OARs剂量,IMRT较WBRT+CRT差异不明显。在临床实践过程中,应当根据患者不同的病灶情况选择合适的放疗方案,以获取更优的临床治疗效果。     

多野照射、三维适形放疗与调强放疗对胃癌根治术患者癌周围组织的影响

目的:探讨多野照射、三维适形放疗与调强放疗对胃癌根治术患者癌周围组织的影响。方法:选取收治的103例行胃癌根治术的患者,将所有患者随机分为甲乙丙三组,其中甲组患者34例,均采用多野照射治疗;而乙组患者也是34例,均使用三维适形放疗;丙组患者则有35例,均使用调强放疗。观察比较各组患者放疗后的上腹部症状改善情况,并且检测各组患者的肝功能和血常规以及胰淀粉酶等临床指标,比较各组患者经治疗后的复发率以及生存率。结果:甲组患者的近期疗效显著低于乙组患者(P0.05),而乙组患者的近期疗效则明显低于丙组患者(P0.05);三组患者的钡餐造影均有所改善,但是其组间比较差异不具有统计学意义(÷2=9.012,P0.05)。甲组的不良反应率显著高于乙组和丙组(均P0.05),并且各组患者的不良反应中血常规异常的发生率显著高于肝功能和胰脏功能的异常(均P0.05),同时甲组患者出现放射性脊髓病的患者明显多于乙组(P0.05),仅丙组患者未见放射性脊髓病。随访三年间三组患者第一年随访生存率无明显差异(P0.05),而在第2年至第3年则三组患者的随访生存率有明显差异(均P0.05),其中随访生存率以丙组患者最高,其次为乙组患者;另外随访三年间甲组患者的随访复发率显著高于乙组和丙组患者(均P0.05),其复发率由低至高依次为丙组乙组甲组。结论:与多野照射治疗相比,三维适形放疗和调强放疗均能够更好地降低对胃癌周围组织的损伤和改善患者的临床症状,并且不良反应发生率低,对于降低复发率和提高生存率方面亦有不错的效果。     

Biochemical relapse free survival rate in patients with prostate cancer treated with external radiotherapy: outcomes obtained at the CMN Siglo XXI Hospital de Oncología,CMN 20 de Noviembre and Hospital General de México of the México City

AimBiochemical relapse-free survival (bRFS) rate is determined by a cohort of Mexican patients (n = 595) with prostate cancer who received treatment with external radiotherapy.BackgroundPatients with prostate cancer were collected from CMN Siglo XXI (IMSS), CMN 20 de Noviembre (ISSSTE), and Hospital General de México (HGM). For the IMSS, 173 patients that are treated with three-dimensional conformal radiation therapy (3D-CRT) and 250 with SBRT, for the ISSSTE 57 patients are treated with 3D-CRT and on the HGM 115 patients are managed with intensity modulated radiation therapy (IMRT). The percentage of patients by risk group is: low 11.1%, intermediate 35.1% and high 53.8%. The average follow-up is 39 months, and the Phoenix criterion was used to determine the bRFS.Materials and methodsThe Kaplan–Meier technique for the construction of the survival curves and, the Cox proportional hazards to model the cofactors.Results(a) The bRFS rates obtained are 95.9% for the SBRT (7 Gy fx, IMSS), 94.6% for the 3D-CRT (1.8 Gy fx, IMSS), 91.3% to the 3D-CRT (2.65 Gy fx, IMSS), 89.1% for the SBRT (7.25 Gy fx, IMSS), 88.7% for the IMRT (1.8 Gy fx, HGM) %, and 87.7% for the 3D-CRT (1.8 Gy fx, ISSSTE). (b) There is no statistically significant difference in the bRFS rates by fractionation scheme, c) Although the numerical difference in the bRFS rate per risk group is 95.5%, 93.8% and 89.1% for low, intermediate and high risk, respectively, these are not statistically significant.ConclusionsThe RT techniques for the treatment of PCa are statistically equivalent with respect to the bRFS rate. This paper confirms that the bRFS rates of Mexican PCa patients who were treated with conventional vs. hypofractionated schemes do not differ significantly.     

Late toxicity for prostate cancer patients treated with hypofractionated helical tomotherapy

AimThe purpose of this study is to evaluate the long term tolerability of hypofractionated helical tomotherapy (HT) in localized prostate cancer patients.BackgroundPrevious hypofractionated schedules with conventional RT were associated with excessive toxicity, likely due to inadequate sophistication of treatment delivery. There are few data about late toxicity after HT.Materials and methodsWe evaluated 38 patients with primary adenocarcinoma of the prostate. There were 9 (24%), 15 (39%), and 14 (37%) patients with high, intermediate, and low risk, respectively. Patients were treated with hypofractionated HT from May 2008 to February 2011. Hypofractionation regimens included: 68.04 Gy at 2.52 Gy/fraction (N = 25; 66%), 70 Gy at 2.5 Gy/fraction (N = 4; 11%) and 70.2 Gy at 2.6 Gy/fraction (N = 9; 23%). Late genitourinary (GU) and gastrointestinal (GI) toxicity was scored using the Radiation Therapy Oncology Group scoring system.ResultsMedian age at diagnosis was 70 years (range 49–80) and median follow-up, 5.8 years. Late grade 1, 2 and 3 GI toxicity were 13%, 24%, and 2.6%, respectively. Late grade 1, 2, 3 GU toxicity were 29%, 21%, and 8%, respectively. Sexual toxicity was evaluated in 19 patients to be grade 1, 2 in 11% and grade 3 in 16%. Multivariate analysis showed that patients with higher values of rectum V50 associated with late GI toxicity (P = 0.025). Patients with PSA ≤8 (P = 0.048) or comorbidities (P = 0.013) at diagnosis were associated with higher late GU toxicity. Additionally, PSA ≤8 also associated with moderate (grade ≥2) late GU toxicity in the multivariate analysis (P = 0.028).ConclusionsHypofractionated HT can be delivered safely with limited rates of moderate and severe late toxicity. The proportion of the rectum that receives a moderate and high dose, having comorbidities, and PSA at diagnosis seem to associate with long term toxicity.