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Objective This study aims to compare the advantages and disadvantages of the three techniques in improving the target volume dose and protecting the auris media cavity and eustachian tube isthmus region by investigating the dosimetric differences of three whole-brain radiotherapy techniques. Methods Thirty patients with whole brain metastases were randomly selected to design fixed field intensity modulated radiotherapy (ff-IMRT) plan, volumetric arc modulated therapy (VMAT) and three-dimensional conformal radiotherapy (3DCRT) plan, and to meet a 95% PTV prescription dose (40 Gy). The dosimetric parameters and monitor units of the target volume and organ at risk (OAR) in the three groups of treatment plans were compared and analyzed. Results The Conformity Index (CI) of the ff-IMRT plan (0.93 ± 0.02) was better than the VMAT plan (0.89 ± 0.01) and the 3DCRT plan (0.73 ± 0.03), respectively, and the difference was statistically significant (P < 0.05). The Homogeneity Index (HI) of the three plans were ff-IMRT (0.05 ± 0.01)、VMAT(0.08 ± 0.1) and 3DCRT (0.08 ± 0.01), respectively, and the difference was not statistically significant (P > 0.05). The Gradient Index (GI) were ff-IMRT (1.77 ± 0.1), VMAT (1.61 ± 0.07), 3DCRT (1.39 ± 0.08), respectively. The difference was statistically significant (P < 0.05). The monitor units (MU) were ff-IMRT (1551.97 ± 85.02), VMAT (303.7 ± 24.28) and 3DCRT (226.2 ± 2.5), respectively, the difference was statistically significant (P < 0.05). The Dmax of the middle ear of the three plans were ff-IMRT (2557.54 ± 477.39) cGy, VMAT (3107.9 ± 362.28) cGy, 3DCRT (4055.37 ± 71.45) cGy, respectively. The Dmax of the eustachian tube isthmus were ff-IMRT (2425 ± 380.4) cGy, VMAT (2902.4 ± 526.3) cGy and 3DCRT (3862.7 ± 135.9) cGy, the difference were statistically significant (P < 0.05). Conclusion In whole-brain radiotherapy, ff-IMRT and VMAT significantly reduced the dose of the bilateral middle ear cavities and eustachian tube isthmus compared with 3DCRT. VMAT is recommended for WBRT for reducing the number of monitor units significantly.
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Objective: To compare overall survival (OS) and intracranial progression-free survival (iPFS) effects of whole-brain radiotherapy (WBRT) and tyrosine kinase inhibitors (TKIs) in NSCLC patients with brain metastases (BM) stratified by EGFR mutation status (mutant, wild-type). Methods: We performed a retrospective analysis of 215 NSCLC BM patients diagnosed in January 2013 to January 2015 with known EGFR status and followed up to December 1, 2016. Stratified Kaplan-Meier curves and multivariate Cox models were used to evaluate the effects of WBRT (defined as≥30 Gy, "W") and TKIs (after BM, "T") on OS and iPFS independently and jointly. Two-sided P>0.20 was considered non-significant (ns). Results: In patients with BM, the mean age was 58 years, 52% were female, and 93% had adenocarcinoma. Those with EGFR mutations (114 patients) had "W" (35 patients) and "T" (87 patients) with adjusted hazard ratios (HRs) (P) of 1.135 (ns) and 0.202 (P<0.001) for OS, respectively, and 1.122 (ns) and 0.275 (P<0.001) for iPFS, respectively. "W+T" (22 patients), "T only" (65 patients), "W only"(13 patients), and "neither" (14 patients) had OS-median survival time (MST) of 14.1, 15.3, 7.1, and 4.3 months, respectively; their iPFS-MST were 14.1, 13.4, 6.8, and 4.5 months, respectively. Their adjusted HRs (P) were 0.196 (P=0.003), 0.114 (P<0.001), 0.434 (ns), 1.000 (ref) for OS, respectively, and 0.272 (P=0.012), 0.200 (P<0.001), 0.622 (ns), 1.000 (ref) for iPFS, respectively. Compared with "T only," "W+T" was not associated with better survival and "W only" had adjusted HRs (P) of 3.804 (P=0.025) for OS and 3.114 (P=0.032) for iPFS. The EGFR wild-type (101 patients) used "W" in 43 patients with OS-MST of 11.3 (7.1) and iPFS of 11.2 (4.8) months; the adjusted HRs (P) of "W"were 0.539 (P=0.105) for OS and 0.485 (P=0.048) for iPFS. Conclusions: In EGFR-mutant NSCLC BM patients, TKIs are associated with improved survival, whether, WBRT alone or combined are not. In cases of EGFR wild-type, WBRT confers the improved the iPFS.
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Background: Whole brain radiotherapy for patients with brain metastasis from lung cancer – prognostic significance of RTOG-RPA score. Aim: To evaluate the prognostic significance of Recursive partition Analysis (RPA) score in predicting the survival in patients with brain metastasis from Non-Small Cell Lung Cancer (NSCLC). Materials and methods: 35 patients diagnosed to have brain metastasis (BM) from primary NSCLC who had received palliative whole brain radiotherapy (WBRT) with or without chemotherapy from March 2014 to Mar 2017 were analyzed in this study. Data regarding the patient age, gender, performance status, histology, number of BM, time of metastasis, neurosurgical resection, radiotherapy details were collected and analyzed. Patients were divided into 3 groups according to RPA classification. The differences in clinical characteristics and treatment variables were analyzed by chi square test and overall survival analysis using Kaplan Mayer. The Cox proportional hazards regression model was used to determine statistically significant variables related to survival. Results: In univariate analysis histology, number of BM, extra cranial metastases, KPS and RPA score were identified to have prognostic significance. The result of multivariate analysis by the Cox proportional hazard model showed that RPA, no of mets and Extra cranial mets were significant. S. Jeeva, K. Chandralekha, V. Vanitha, M. Sornam, Balasubramanium, P. Vidya. Whole brain radiotherapy for patients with brain metastasis from lung cancer – Prognostic significance of RTOG-RPA score. IAIM, 2019; 6(5): 32-39. Page 33 Conclusions: Our study showed that RPA is good prognostic indicator in assessing the prognosis of patients with brain metastasis in NSCLC.
ABSTRACT
Lung cancer is a malignant tumor,leading to the highest morbidity and mortality worldwide.Non-small cell lung cancer (NSCLC)accounts for approximately 80% of all lung cancer types.Out of all the patients with advanced NSCLC,more than 40% develop brain metastasis,and lung cancer associated with brain metastasis indicates poor prognosis.Traditional treatment options,such as ra-diotherapy,chemotherapy and surgery,have an extremely limited role in improvement of prognosis of such patients.In recent years, with the development of stereotactic radiotherapy and targeted therapy,particularly chemotherapy combined with targeted therapy, radiotherapy combined with targeted therapy and other types of therapies,NSCLC patients with brain metastases could benefit from these therapies with an improved quality of life and prolonged median overall survival. However, the ideal treatment regimen for NSCLC patients with brain metastases remains controversial.Recent advances in NSCLC with brain metastases will be described elabo-rately in this paper,to provide a theoretical basis for selecting a reasonable treatment plan for non-small lung cancer patients with brain metastasis.