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Lung cancer is largely classified into two types according to its histology, small cell and nonsmall cell, and has diverse situations for which radiotherapy is indicated. Radiation therapy plays a major role in the treatment strategy for both types of lung cancer. Since the treatment of lung cancer is extremely complex, it is essential to develop an appropriate treatment strategy by combining surgery, radiotherapy, and systemic therapy (chemotherapy, immunotherapy, and molecular-targeted drugs) according to each stage of the disease. Radiotherapy is indicated, from curative intent to palliative treatment, at any stage of the disease. Current radiotherapy, which incorporates diagnostic imaging and physical engineering, has made significant progress, making it possible to increase the local control rate while reducing the radiation dose to at-risk organs. Herein, we review the basics of the current perspective of radiotherapy and the current role of radiotherapy in lung cancer treatment according to each stage of the disease.

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Aim: The study aims to evaluate the differences in dosimetry between tandem-ovoid (TO) and tandem-ring (TR) gynecologic brachytherapy applicators using different optimizing techniques in image-based brachytherapy. Background: Conventionally, TO applicators are in use to deliver doses to tumor in intracavitary brachytherapy. Nowadays, different types of applicators are available for cervical cancer brachytherapy treatment such as TR, tandem-cylinder, hybrid intracavitary, and interstitial applicators. Materials and Methods: In the present study, we used a TR and Fletcher-style TO applicator in the same patient, in two different sessions of brachytherapy. Four plans were generated for each patient, utilizing two different optimization techniques for each applicator used. A dose of 9 Gy (Gray) was prescribed and plans were normalized to left point A, and in other techniques, the optimization is done to achieve the recommended organ at risk (OAR) dose–volume constraints. Dose–volume and dose point parameters were compared. Results: The results indicate that the (OAR doses assessed by dose–volume histogram criteria were lower than the International Commission on Radiation Units and Measurements (ICRU) point doses for bladder and rectum with both TO and TR applicators for point A normalized plans. Both bladder and sigmoid received higher doses in TO than in TR but were statistically not significant (NS), but the rectum doses are higher in TR than in TO and it was statistically significant. The isodose volumes are higher in point A normalized plans than in OAR-based optimized plans in both applicators. The ICRU point doses are lower in OAR optimized plans than in point A normalized plans in both applicators. Conclusions: TO and TR applicators are commonly used gynecological intracavitary applicators. In this present study we did not find any significant difference between doses delivered to ICRU Point and Isodose volumes, after using both applicators .Critical OAR doses were also comparable. The only advantage of the ring applicator is, it provides an additional degree of freedom to load the vaginal sources over the ovoids and easy application in cases of narrow fornices with greater reproducibility.

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Purpose: Vertebral compression fractures frequently present with back pain and are determined by magnetic resonance (MR) imaging. However, fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) is performed to determine the pathological fractures and primary tumors in a single imaging modality. The aim of this study is to evaluate the incidence of pathological fractures and primary tumors by means of combined bone scintigraphy and FDG PET/CT. Materials and Methods: Twenty-eight patients (15 females, 13 males; mean: 67.8 ± 11.6 years) with compression fractures determined by MR or plain radiographs were the subject of this study. The patients were referred for whole-body bone scintigraphy and due to the suspicion of metastasis additional FDG PET/CT was performed. The results of both studies were compared with the pathological and/or follow-up results. Results: The bone scintigraphy and PET/CT did not reveal concordant results according to the Kappa test. The SUVmax cutoff value was accepted as “7” and with this cutoff value, PET/CT achieved 57.1% sensitivity and 95.2% specificity in the determination of pathologic compression fractures. Conclusion: Although the results of bone scintigraphy and FDG PET/CT were not correlated with each other, FDG PET/CT revealed high specificity in the detection of pathologic fractures.

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