Purpose: The physical properties of proton therapy allow for decreased dose delivery to nontarget structures. The purpose of this study was to determine if this translates into a clinical benefit by comparing acute and chronic morbidity between patients with nasopharyngeal carcinoma who are treated with intensity-modulated proton therapy (IMPT) and those treated with intensity-modulated radiation therapy (IMRT). Materials and Methods: Patients receiving IMPT for nasopharyngeal cancer from 2011-13 were matched in a 2:1 IMPT to IMRT ratio. Matching criteria were, in order, T-stage, N-stage, radiation dose, chemotherapy type, World Health Organization classification, sex, and age. Results: Ten patients treated with IMPT and 20 matched patients treated with IMRT were included. By the end of treatment, 2 IMPT-treated patients (20%) and 13 IMRTtreated patients (65%) required gastrostomy tube (GT) insertion (P ¼ .020). Patients receiving IMPT had significantly lower mean doses to the oral cavity, brainstem, whole brain, and mandible. Increased mean dose to the oral cavity was associated with a higher rate of GT placement (P , .001), but mean dose to the brainstem, whole brain, and mandible was not. Partitioning analysis showed that no patient required GT insertion if the mean oral cavity dose was ,26 Gy, but all patients with a mean oral cavity dose. 41.8 Gy required GT insertion. Treatment type (IMPT versus IMRT), induction chemotherapy (yes versus no), mean oral cavity dose, mean brainstem dose, and mean mandible dose were entered into the multivariable model. Only higher mean oral cavity dose remained significantly associated with higher GT rates on multivariable analysis http://theijpt.org

To test the hypothesis on prolonged survival in glioblastoma cases with increased subventricular zone (SVZ) radiation dose. Sixty glioblastoma cases were previously treated with adjuvant radiotherapy and Temozolamide. Ipsilateral, contralateral and bilateral SVZs were contoured and their doses were retrospectively evaluated. Median follow-up, progression free survival (PFS) and overall survival (OS) were 24.5, 8.5 and 19.3 months respectively. Log-rank tests showed a statistically significant correlation between contralateral SVZ (cSVZ) dose > 59.2 Gy (75th percentile) and poor median PFS (10.37 [95% CI 8.37-13.53] vs 7.1 [95% CI 3.5-8.97] months, p = 0.009). cSVZ dose > 59.2 Gy was associated with poor OS in the subgroup with subtotal resection/biopsy (HR: 4.83 [95% CI 1.71-13.97], p = 0.004). High ipsilateral SVZ dose of > 62.25 Gy (75th percentile) was associated with poor PFS in both subgroups of high performance status (HR: 2.58 [95% CI 1.03-6.05], p = 0.044) and SVZ without tumoral contact (HR: 10.57 [95% CI 2.04-49], p = 0.008). The effect of high cSVZ dose on PFS lost its statistical significance in multivariate Cox regression analysis. We report contradictory results compared to previous publications. Changing the clinical practice based on retrospective studies which even do not indicate consistent results among each other will be dangerous. We need carefully designed prospective randomized studies to evaluate any impact of radiation to SVZ in glioblastoma.

Normal tissues--particularly the parotid glands--are better spared with the arc technique in patients with NPC. MU and treatment times are considerably reduced in arc IMRT plans.

Objectives: To evaluate accuracy of FDG-PET CT in prediction of persistent disease in head and neck cancer cases and to determine prognostic value of metabolic tumor response. Materials and Methods: Between 2009 and 2011, 46 patients with squamous cell carcinoma of head and neck receiving PET-CT were treated with definitive radiotherapy, with or without chemotherapy. There were 29 nasopharyngeal, 11 hypopharyngeal, 3 oropharyngeal and 3 laryngeal cancer patients, with a median age of 50.5 years (range 16-84), 32 males and 14 females. All patients were evaluated with PET-CT median 3-5 months (2.4-9.4) after completion of radiotherapy. Results: After a median 20 months of follow up, complete metabolic response was observed in 63% of patients. Suspicious residual uptake was present in 10.9% and residual metabolic uptake in 26.0% of patients. The overall sensitivity, specificity, positive predictive value and negative predictive value of FDG-PET-CT for detection of residual disease was 91% and 81%, 64% and 96% respectively. Two year LRC was 95% in complete responders while it was 34% in non-complete responders. Conclusions: FDG PET CT is a valuable tool for assessment of treatment response, especially in patients at high risk of local recurrence, and also as an indicator of prognosis. Definitely more precise criteria are required for assessment of response, there being no clear cut uptake value indicating residual disease. Futhermore, repair processes of normal tissue may consume glucose which appear as increased uptake in control FDG PET CT.

L ung cancer is known to be the most commonly diagnosed cancer with high mortality and morbidity. Lung cancer is divided into two groups as non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). These two groups should be seen as two different diseases concerning their clinical course. 80-85% of newly diagnosed lung cancer patients are NSCLC, and 15-20% is SCLC. According to Turkey cancer statistics in 2017, lung cancer is the first in cancer rate in men (52.5/100.000) and the fifth most common type of cancer in women (8.7/100000). 1-The Role of Radiotherapy in Non-Small Cell Lung Cancer Non-small cell lung cancer (NSCLC), which forms the majority of lung cancers, consists of squamous cell cancer, adenocarcinoma and large cell cancers. Although surgical resection is curative in the group without severe concomitant disease at the early-stage, radiosurgery has taken its place as the standard treatment approach in patients with comorbid disease. However, this group covers only 30% of the patients. [1, 2] Radiotherapy can be applied as definitive in the group with local and regional advanced disease with no surgical chance, as neoadjuvant in the group that has the potential to have surgery and can be applied as adjuvant considering some risk factors after surgery. Radiotherapy in metastatic disease is often used for palliative purposes, but radiosurgery may be an option for metastases in oligometastatic disease. 1A-Early Stage (I-II) Stereotactic Body Radiotherapy or Lung Radiosurgery Radiosurgery, which was introduced to our practice by Swedish brain surgeon Lars Leksell in 1950, was first used in the treatment of brain lesions. With the development Lung cancer is divided into two subgroups concerning its natural course and treatment strategies as follows: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). In this review, for NSCLC, the role of stereotactic body radiation therapy (SBRT) in early-stage, chemoradiation in the locally advanced stage, post-operative radiotherapy for patients with high risk after surgery and radiotherapy for metastatic disease will be discussed. Also, for SCLC, the role and timing of thoracic irradiation and prophylactic cranial irradiation (PCI) for the limited and extensive stages will be discussed.