Download the Free Unbound MEDLINE PubMed App to your smartphone or tablet.
Available for iPhone, iPad, iPod touch, and Android.
conformal radiation therapy [keywords]
- Combined chemo-radiotherapy in locally advanced nasopharyngeal carcinomas. [Journal Article]
- World J Clin Oncol 2013 May 10; 4(2):47-51.
To provide efficacy and safety data about the combined use of radiotherapy and chemo-radiotherapy in nasopharyngeal carcinoma (NPC).We reviewed data of 40 patients with locally advanced NPC treated with induction chemotherapy followed by concomitant chemo-radiotherapy (CCRT) (22/40 patients) or CCRT alone (18/40) from March 2006 to March 2012. Patients underwent fiberoscopy with biopsy of the primitive tumor, and computed tomography scan of head, neck, chest and abdomen with and without contrast. Cisplatin was used both as induction and as concomitant chemotherapy, while 3D conformal radiation therapy was delivered to the nasopharynx and relevant anatomic regions (total dose, 70 Gy). The treatment was performed using 6 MV photons of the linear accelerator administered in 2 Gy daily fraction for five days weekly. This retrospective analysis was approved by the review boards of the participating institutions. Patients gave their consent to treatment and to anonymous analysis of clinical data.Thirty-three patients were males and 7 were females. Median follow-up time was 58 mo (range, 1-92 mo). In the sub-group of twenty patients with a follow-up time longer than 36 mo, the 3-year survival and disease free survival rates were 85% and 75%, respectively. Overall response rate both in patients treated with induction chemotherapy followed by CCRT and in those treated with CCRT alone was 100%. Grade 3 neutropenia was the most frequent acute side-effect and it occurred in 20 patients. Grade 2 mucositis was seen in 29 patients, while grade 2 xerostomia was seen in 30 patients. Overall toxicity was manageable and it did not cause any significant treatment delay. In the whole sample population, long term toxicity included grade 2 xerostomia in 22 patients, grade 1 dysgeusia in 17 patients and grade 1 subcutaneous fibrosis in 30 patients.Both CCRT and induction chemotherapy followed by CCRT showed excellent activity in locally advanced NPC. The role of adjuvant chemotherapy remains to be defined.
- Intensity-modulated radiotherapy vs. conventional radiotherapy in the treatment of anal squamous cell carcinoma: A propensity score analysis. [JOURNAL ARTICLE]
- Radiother Oncol 2013 May 18.
BACKGROUND AND PURPOSE:Definitive chemoradiation is the standard management for anal squamous cell carcinoma (ASCC); more conformal pelvic radiotherapy using intensity modulated radiotherapy (IMRT) minimizes toxicity but may increase locoregional recurrences (LRR). We compared IMRT and conventional radiotherapy (CRT) outcomes in ASCC patients.
MATERIAL AND METHODS:We retrospectively reviewed records of 223 ASCC patients treated at Memorial Sloan-Kettering Cancer Center from 1991 to 2010. Forty-five patients received IMRT and 178 CRT. We determined locoregional recurrence-free survival (LRFS), distant metastases-free survival (DMFS), and overall survival (OS) for each radiation modality. A propensity score analysis was performed using potentially confounding variables. Locoregional and distant patterns of failure for CRT and IMRT were compared.
RESULTS:Patients treated with IMRT had significantly higher N stage (P<.01), and were less likely to be treated with induction chemotherapy (P=.01). The 2-year LRFS, DMFS, and OS were 87%, 86%, and 93%, respectively, for IMRT; and 82%, 88%, 90%, respectively, for CRT; with no significant difference in outcomes by univariate analysis or in a propensity score analysis adjusted for disparity between the groups.
CONCLUSIONS:This large, single-institution experience of definitive chemoradiation for ASCC using CRT vs. IMRT demonstrates that outcomes are not compromised by more conformal radiotherapy. In the absence of prospective, multi-institutional, randomized trials of IMRT in ASCC, these retrospective data, using methods to minimize bias, can help to establish the role of IMRT in the definitive therapy of ASCC.
- Comparative Effectiveness of Intensity-Modulated Radiotherapy and Conventional Conformal Radiotherapy in the Treatment of Prostate Cancer After Radical Prostatectomy. [JOURNAL ARTICLE]
- JAMA Intern Med 2013 May 20.:1-8.
IMPORTANCE Comparative effectiveness research of prostate cancer therapies is needed because of the development and rapid clinical adoption of newer and costlier treatments without proven clinical benefit. Radiotherapy is indicated after prostatectomy in select patients who have adverse pathologic features and in those with recurrent disease.
OBJECTIVESTo examine the patterns of use of intensity-modulated radiotherapy (IMRT), a newer, more expensive technology that may reduce radiation dose to adjacent organs compared with the older conformal radiotherapy (CRT) in the postprostatectomy setting, and to compare disease control and morbidity outcomes of these treatments. DESIGN AND SETTING Data from the Surveillance, Epidemiology, and End Results-Medicare-linked database were used to identify patients with a diagnosis of prostate cancer who had received radiotherapy within 3 years after prostatectomy. PARTICIPANTS Patients who received IMRT or CRT. MAIN OUTCOMES AND MEASURES The outcomes of 457 IMRT and 557 CRT patients who received radiotherapy between 2002 and 2007 were compared using their claims through 2009. We used propensity score methods to balance baseline characteristics and estimate adjusted incidence rate ratios (RRs) and their 95% CIs for measured outcomes.
RESULTSUse of IMRT increased from zero in 2000 to 82.1% in 2009. Men who received IMRT vs CRT showed no significant difference in rates of long-term gastrointestinal morbidity (RR, 0.95; 95% CI, 0.66-1.37), urinary nonincontinent morbidity (0.93; 0.66-1.33), urinary incontinence (0.98; 0.71-1.35), or erectile dysfunction (0.85; 0.61-1.19). There was no significant difference in subsequent treatment for recurrent disease (RR, 1.31; 95% CI, 0.90-1.92).
CONCLUSIONSAND RELEVANCE Postprostatectomy IMRT and CRT achieved similar morbidity and cancer control outcomes. The potential clinical benefit of IMRT in this setting is unclear. Given that IMRT is more expensive, its use for postprostatectomy radiotherapy may not be cost-effective compared with CRT, although formal analysis is needed.
- Expanding Utilization of Intensity-Modulated Radiotherapy for Prostate Cancer: Comment on "Comparative Effectiveness of Intensity-Modulated Radiotherapy and Conventional Conformal Radiotherapy in the Treatment of Prostate Cancer After Radical Prostatectomy" [JOURNAL ARTICLE]
- JAMA Intern Med 2013 May 20.:1-2.
- [Radiotherapy for localized prostate cancer (with and without hormonal treatment)]. [English Abstract, Journal Article]
- Rev Prat 2013 Apr; 63(4):503-8.
External beam radiotherapy (EBRT) for non metastatic prostate cancer has evolved during the past two decades with the introduction of image-based treatment planning and technological progress. When controlled for various case selection factors and quality of treatment delivery, the outcomes among the various modalities of treatments (surgery, EBRT, brachytherapy) appear to be equivalent. Newer conformal radiotherapy (RT) methods with three-dimensional conformal RT (3D-CRT) with intensity-modulated RT (IMRT) and image guided RT, have allowed radiation oncologists to improve the therapeutic ratio by lowering the dose to the surrounding critical structures while simultaneously safely escalating the dose to the disease target. This review details the practical elements of radiation dose delivery and the main guidelines for use of radiation therapy.
- [Dosimetric Comparing between Protons Beam and Photons Beam for Lung Cancer Radiotherapy: A Meta-analysis]. [English Abstract, Journal Article]
- Zhongguo Fei Ai Za Zhi 2013 May 20; 16(5):252-60.
The clinical evidences are not sufficient on the proton beam therapy of lung cancer for lacking of the RCTs on the comparing the proton with the photon beam in lung cancer radiotherapy. The aim of this study is to evaluate the dosimetry superiority of the proton beam and provide more valuable evidences to the clinical researches.Clinical trails of dosimetric comparing between protons beam and photons beam for lung cancer radiotherapy were obtained from the Cochrane library, Pubmed, EMbase, CBM, CNKI, VIP, and Wan Fang databases. The data included in the study were evaluated and analyzed using the Cochrane Collaboration's RevMan 5.2 software.Six trails were included. Compared to photon therapy (three-dimensional conformal photon radiotherapy, 3D-CRT), the proton therapy had a significantly lower total lung Dmean (MD=-4.15, 95%CI: -5.56--2.74, P<0.001) and V20, V10, V5 (MD=-10.92, 95%CI: -13.23--8.62, P<0.001); The V20, V10, V5 significantly decreased in proton therapy group. Compared to photon therapy (intensity-modulated photon radiotherapy, IMRT), V20, V10, V5 were also significantly lowered in proton therapy group (MD=-3.70, 95%CI: -5.31--2.10, P<0.001; MD=-8.86, 95%CI: -10.74--6.98, P<0.001; MD=-20.13, 95%CI: -27.11--13.14, P<0.001); The esophagus Dmean was not lowered, while the heart Dmean decreased in proton therapy group.Comparing to photon beam radiotherapy (3D-CRT and IMRT), proton beam therapy is advantageous in dosimetry of the lung cancer radiotherapy and recommended for clinical applying.
- MR Imaging of Prostate Cancer in Radiation Oncology: What Radiologists Need to Know. [Journal Article]
- Radiographics 2013 May; 33(3):741-61.
Radiation therapy (RT) is one of the principal treatment modalities for localized or locally advanced prostate cancer. The two major forms of RT for prostate cancer are external-beam RT (EBRT) with a photon or proton beam and brachytherapy. With modern conformal techniques for EBRT (three-dimensional conformal RT, intensity-modulated RT, and image-guided RT) and advanced computer-based planning systems for brachytherapy, the dose can be more precisely delivered to the prostate while reducing unnecessary radiation to normal tissue. The dominant intraprostatic tumor can be targeted with a higher dose, so-called dose painting. Magnetic resonance (MR) imaging plays a pivotal role in pretreatment assessment of prostate cancer. Multiparametric MR imaging, a combination of anatomic and functional MR imaging techniques (diffusion-weighted imaging, dynamic contrast material-enhanced imaging, and MR spectroscopy), significantly improves the accuracy of tumor localization and local staging. For pretreatment planning, anatomic MR imaging provides highly accurate local staging information, particularly about extraprostatic extension and seminal vesicle invasion. The dominant intraprostatic tumor and local recurrence in the prostatectomy bed can be better localized with multiparametric MR imaging for dose painting. MR imaging allows excellent delineation of the contours of the prostate and surrounding structures. It can also be used in early posttreatment evaluation after brachytherapy.
- Volumetric modulated arc radiotherapy for limited osteosclerotic myeloma. [Journal Article]
- World J Radiol 2013 Apr 28; 5(4):173-7.
To assess the feasibility of volumetric intensity-modulated arc radiotherapy (VMAT) in patients with limited polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes syndrome.A 70-year-old male with histologically confirmed osteosclerotic myeloma was treated in our department in July 2010 with VMAT. Fourty-six Gray in 23 fractions were given on three bone lesions. Doses delivered to target volume and critical organs were compared with a tridimensional conformal radiotherapy (3D-RT) plan. Treatment was well tolerated without any side effects.VMAT improved dose homogeneity within the target volume, as compared to 3D-RT (standard deviations: 2.9 Gy and 1.6 Gy for 3D and VMAT, respectively). VMAT resulted in a better sparing of critical organs. Dose delivered to 20% of organ volume (D20) was reduced from 22 Gy (3D-RT) to 15 Gy (VMAT) for small bowel, from 24 Gy (3D-RT) to 17 Gy (VMAT) for bladder and from 47 Gy (3D-RT) to 3 Gy (VMAT) for spinal cord. Volumes of critical organs that received at least 20 Gy (V20) were decreased by the use of VMAT, as compared to 3D-RT (V20 bladder: 10% vs 99%; V20 small bowel: 6% vs 21%). One year after treatment completion, no tumor progression has been reported.VMAT improved dose distribution as compared to 3D-RT for limited osteosclerotic myeloma, with better saving of critical organs.
- A Novel Method for Predicting Late Genitourinary Toxicity After Prostate Radiation Therapy and the Need for Age-Based Risk-Adapted Dose Constraints. [JOURNAL ARTICLE]
- Int J Radiat Oncol Biol Phys 2013 May 9.
BACKGROUND:There are no well-established normal tissue sparing dose-volume histogram (DVH) criteria that limit the risk of urinary toxicity from prostate radiation therapy (RT). The aim of this study was to determine which criteria predict late toxicity among various DVH parameters when contouring the entire solid bladder and its contents versus the bladder wall. The area under the histogram curve (AUHC) was also analyzed.
METHODS AND MATERIALS:From 1993 to 2000, 503 men with prostate cancer received 3-dimensional conformal RT (median follow-up time, 71 months). The whole bladder and the bladder wall were contoured in all patients. The primary endpoint was grade ≥2 genitourinary (GU) toxicity occurring ≥3 months after completion of RT. Cox regressions of time to grade ≥2 toxicity were estimated separately for the entire bladder and bladder wall. Concordance probability estimates (CPE) assessed model discriminative ability. Before training the models, an external random test group of 100 men was set aside for testing. Separate analyses were performed based on the mean age (≤ 68 vs >68 years).
RESULTS:Age, pretreatment urinary symptoms, mean dose (entire bladder and bladder wall), and AUHC (entire bladder and bladder wall) were significant (P<.05) in multivariable analysis. Overall, bladder wall CPE values were higher than solid bladder values. The AUHC for bladder wall provided the greatest discrimination for late bladder toxicity when compared with alternative DVH points, with CPE values of 0.68 for age ≤68 years and 0.81 for age >68 years.
CONCLUSION:The AUHC method based on bladder wall volumes was superior for predicting late GU toxicity. Age >68 years was associated with late grade ≥2 GU toxicity, which suggests that risk-adapted dose constraints based on age should be explored.
- Stereotactic Body Radiotherapy in Patients With Stage I Non-Small-Cell Lung Cancer Aged 75 Years and Older: Retrospective Results from a Multicenter Consortium. [JOURNAL ARTICLE]
- Clin Lung Cancer 2013 May 6.