Intensity modulated radiation therapy (IMRT) is increasingly employed in glioblastoma (GBM) treatment. The present work aimed to assess which clinical-dosimetric scenario could benefit the most from IMRT application, with respect to three-dimensional conformal radiation therapy (3D-CRT). The number of organs at risk (OARs) overlapping the planning target volume (PTV) was the parameter describing the clinical-dosimetric pattern. Based on the results, a dosimetric decision criterion to select the most appropriate treatment technique is provided. Seventeen previously irradiated patients were retrieved and re-planned with both 3D-CRT and IMRT. The prescribed dose was 60 Gy/30fx. The cases were divided into 4 groups (4 patients in each group). Each group represents the scenario where 0, 1, 2 or 3 OARs overlapped the target volume, respectively. Furthermore, in one case, 4 OARs overlapped the PTV. The techniques were compared also in terms of irradiated healthy brain tissue. The results were evaluated by paired t-test. IMRT always provided better target coverage (V95%) than 3D-CRT, regardless the clinical-dosimetric scenario: difference ranged from 0.82% (p = 0.4) for scenario 0 to 7.8% (p = 0.02) for scenario 3, passing through 2.54% (p = 0.18) and 5.93% (p = 0.08) for scenario 1 and 2, respectively. IMRT and 3D-CRT achieved comparable results in terms of dose homogeneity and conformity. Concerning the irradiation of serial-kind OARs, both techniques provided nearly identical results. A statistically significant dose reduction to the healthy brain in favor of IMRT was scored. IMRT seems a superior technique compared to 3D-CRT when there are multiple overlaps between OAR and PTV. In this scenario, IMRT allows for a better target coverage while maintaining equivalent OARs sparing and reducing healthy brain irradiation. The results from our patients dataset suggests that the overlap of three OARs can be used as a dosimetric criterion to select which patients should receive IMRT treatment.

Owing to low radiation dose and sufficient image quality, CBCT could be considered an adequate technique for postoperative imaging and follow-up of patients with bionic ear implants.

Using T(2) MRI, huge variations can be observed in peritumoural oedema, which are probably due to steroid treatment. Using T(1) MRI, brain shifts after surgery and possible progressive enhancing lesions produce substantial differences in CTVs. Our data support the use of post-operative/pre-radiotherapy T(1) weighted MRI for planning purposes.

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A retrospective analysis of 183 consecutive patients with tonsillar carcinoma obserevd from 1970 through 1984 and treated by external radiotherapy was carried out. The data were analyzed retrospectively to determine the factors affecting prognosis. Tumor size (T) and lymph node involvement (N) were found to be predominant prognostic factors. The difference in 5 year survival rate between T2 and T3 tumors was significant, and that between N1 and N3 was highly significant, whereas difference in survival could be found between N0 and N1 groups. The primary tumor was controlled by radiotherapy alone in 90% of cases of T1 lesions, 58% of T2, 37% of T3 and 11% of T4, and lymph node metastases was controlled in 70% of N1 cases, 0 of N2 and 15.5% of N3. Twenty-three patients underwent salvage surgery after radiotherapy had failed and the actuarial 5 year survival rate was 75% for stage I, 40% for stage II, 30% for stage III and 13% for stage IV.