To evaluate the role of postoperative radiotherapy (PORT) in intracranial solitary fibrous tumor/hemangiopericytoma (SFT/HPC). Methods and Materials A total of 133 patients with histologically confirmed HPC were included from 8 institutions. Gross total resection (GTR) and subtotal resection (STR) were performed in 86 and 47 patients, respectively. PORT was performed in 85 (64%) patients. The prognostic effects of sex, age, performance, WHO grade, location, size, Ki-67, surgical extent, and PORT on local control (LC), distant metastasis-free survival (DMFS), progression-free survival (PFS), and overall survival (OS) were estimated by univariate and multivariate analyses. Results The 10-year PFS, and OS rates were 45%, and 71%, respectively. The multivariate analysis suggested that PORT significantly improved LC (p<0.001) and PFS (p<0.001). The PFS benefit of PORT was maintained in the subgroup of GTR (p=0.001), WHO grade II (p=0.001) , or STR (p<0.001). In the favorable subgroup of GTR and WHO grade II, PORT was also significantly related to better PFS (p=0.028). WHO grade III was significantly associated with poor DMFS (p=0.029). In the PORT subgroup, the 0-0.5 cm margin of the target volume showed an inferior LC to a large margin with 1.0-2.0 cm (p=0.021). Time-dependent Cox proportion analysis showed that distant failures were significantly associated with poor OS (p=0.003). Conclusion This multicenter study supports the role of PORT in disease control of intracranial SFT/HPC, irrespective of the surgical extent and grade. For LC, PORT should enclose the tumor bed with sufficient margin.

IMRT significantly reduced acute toxicity in locally advanced rectal cancer patients treated with NCRT compared to 3DCRT.

This study was designed to investigate the impact of interim progression of disease (PD) during the surgery-to-radiotherapy interval (SRI) and its predictors in glioblastoma based on MRIs. A total of 222 patients were planned for radiotherapy (RT) and 166 of them were evaluable for the presence of interim PD by 2 separate MRIs. The size criteria from the updated Response Assessment in Neuro-Oncology criteria was adopted to determine interim PD. 32 (19.3%) patients experienced interim PD, and their median survival (MS) was shorter than patients without PD in univariate (11.3 vs. 19.6 months, p < 0.001) and multivariate analysis (HR 2.237, 95% CI 1.367-3.660, p = 0.002). The volume of residual enhancing tumor (p = 0.003) and prolongation of the SRI (p = 0.004) were significant predictors of interim PD. Every 1-cc increase in residual enhancing tumor and every 1-day prolongation of the SRI significantly increased the risk of interim PD by 3.9% (p = 0.003) and 8.1% (p = 0.004), respectively. A significant portion of patients demonstrate interim PD during SRI and these patients have poor prognosis. The presence of interim PD should be concerned as a significant confounding factor for stratification in future clinical trials. A baseline pre-RT MRI is essential for accurate disease evaluation and RT-target delineation, especially in patients with larger residual disease after surgery and prolonged SRI due to the high risk of interim PD.

BackgroundThis study aimed for a collaborative evaluation of variability in the target volumes for glioblastoma, determined and contoured by different radiotherapy (RT) facilities in Korea.MethodsFifteen panels of radiation oncologists from independent institutions contoured the gross target volumes (GTVs) and clinical target volumes (CTVs) for 3-dimensional conformal RT or intensity-modulated RT on each simulation CT images, after scrutinizing the enhanced T1-weighted and T2-weighted-fluid-attenuated inversion recovery MR images of 9 different cases of glioblastoma. Degrees of contouring agreement were analyzed by the kappa statistics. Using the algorithm of simultaneous truth and performance level estimation (STAPLE), GTVSTAPLE and CTVSTAPLE contours were derived.ResultsContour agreement was moderate (mean kappa 0.58) among the GTVs and was substantial (mean kappa 0.65) among the CTVs. However, each panels’ GTVs and modification of CTVs regarding anatomical structures varied. Three-fourth of contoured panels’ CTVs encompassed the peritumoral areas of T2-high signal intensity (T2-HSI). Nine of nine GTVSTAPLE encompased the surgical cavity and the T1-enhanced lesions. Eight of nine CTVSTAPLE encompassed the peritumoral T2-HSI area. The median MARGIN90 and the median MARGIN95 were 1.4 cm and 1.5 cm, respectively.ConclusionsModerate to substantial agreement existed in target volumes for 3-dimensional or intensity-modulated RT determined by radiation oncologists in Korea. According to the estimated consensus contours, the initial CTV encompassed the GTV with margin less than 2.0 cm and the whole peritumoral areas of T2-HSI. The findings of our study propose the need for further studies and modified guidelines.Electronic supplementary materialThe online version of this article (doi:10.1186/s13014-015-0439-z) contains supplementary material, which is available to authorized users.