Radiation therapy remains important in the modern management of both Hodgkin and non-Hodgkin lymphoma. Radiation is applied as both consolidation therapy post chemotherapy and primary therapy for selected limited volume clinically favorable histology. Application of modern therapy techniques permits more sparing of normal tissue in all anatomical locations. Modern image guidance permits both security in daily patient treatment set up and permits strategic titration of the planning target volume to further spare normal tissue. Four-dimensional planning makes certain targets are fully treated in all phases of the breathing cycle. Dose painting with altered fractionation permits identification of low, intermediate, and high-risk areas of concern and treat each in a single plan with multiple fractionation schemes saving both time of treatment and cost of therapy. In this paper we present multiple examples of the application of modern therapy techniques in lymphoma management and demonstrate advantages of modern radiation in several anatomical regions.
Cancer remains a significant medical challenge for modern health care. Therapies have improved. Chemotherapy can now be applied and targeted to specific expression products and biomarkers. Radiation therapy is directed to specific targets with applied image guidance including less normal tissue in the treatment fields. Surgery has improved with robotics and improvements in rehabilitation and recovery. More patients are surviving their primary challenge from malignancy. As such, more patients now have the imprint of therapy upon their normal tissues. It is important for all practitioners, including primary care physicians and medical subspecialists, to participate in the aftercare of these patients with a comprehensive strategic manner to both prevent normal tissue injury and ameliorate injury if/when it occurs.
Dystrophic calcification in breast tissue and the chest wall is a common finding in patients undergoing definitive therapy including radiation treatment for breast cancer. In this report, we correlate significant and symptomatic dystrophic dense calcification as a late treatment effect associated with radiation therapy and correlate dosimetry and radiation dose and daily dose fractionation asymmetry to the development of calcifications.
Three years following endovascular embolization of a 3 mm ruptured arteriovenous malformation (AVM) of the left superior colliculus in a 42-year-old man, digital subtraction angiography showed continuous regrowth of the lesion. Thin-slice MRI acquired for treatment planning did not show the AVM nidus. The patient was brought back to the angiography suite for high-resolution contrast-enhanced cone beam CT (VasoCT) acquired using an angiographic c-arm system. The lesion and nidus were visualized with VasoCT. MRI, CT and VasoCT data were transferred to radiation planning software and mutually co-registered. The nidus was annotated for radiation on VasoCT data by an experienced neurointerventional radiologist and a dose/treatment plan was completed. Due to image registration, the treatment area could be directly adopted into the MRI and CT data. The AVM was completely obliterated 10 months following completion of the radiosurgery treatment.
PURPOSE:Chest wall pain and discomfort has been recognized as a significant late effect of radiation therapy in historical and modern treatment models. Stereotactic Body Radiotherapy (SBRT) is becoming an important treatment tool in oncology care for patients with intrathoracic lesions. For lesions in close approximation to the chest wall with motion management, SBRT techniques can deliver high dose to the chest wall. As an unintended target of consequence, there is possibility of imposing significant chest wall pain and discomfort as a late effect of therapy. The purpose of this paper is to evaluate the potential role of Volume Modulated Arc Therapy (VMAT) technologies in decreasing chest wall dose in SBRT treatment of pulmonary lesions in close approximation to the chest wall.MATERIALS AND METHODS:Ten patients with pulmonary lesions of various sizes and tomography in close approximation to the chest wall were selected for retrospective review. All volumes including tumor target, chest wall, ribs, and lung were contoured with maximal intensity projection maps and four-dimensional computer tomography planning. Radiation therapy planning consisted of static techniques including Intensity Modulated Radiation Therapy compared to VMAT therapy to a dose of 60 Gy in 12 Gy fraction dose. Dose volume histogram to rib, chest wall, and lung were compared between plans with statistical analysis.RESULTS:In all patients, dose and volume were improved to ribs and chest wall using VMAT technologies compared to static field techniques. On average, volume receiving 30 Gy to the chest wall was improved by 74%; the ribs by 60%. In only one patient did the VMAT treatment technique increase pulmonary volume receiving 20 Gy (V20).CONCLUSIONS:VMAT technology has potential of limiting radiation dose to sensitive chest wall regions in patients with lesions in close approximation to this structure. This would also have potential value to lesions treated with SBRT in other body regions where targets abut critical structures.
Purpose Radiation therapy has shown to be an effective treatment of brain arteriovenous malformations (bAVMs). 1 2 Target delineation is commonly performed on volumetric image data, such as MRI or CT data. However, the nidi of micro-AVMs may not be visualized adequately by these modalities due to their limited image resolution. In this report, we show a novel usage of high-resolution contrast-enhanced cone-beam computed tomography (CBCT) imaging and multi-modal image registration 3 for radiation target delineation of a micro-AVM, a technique previously suggested for larger AVMs. 4 Case A 42-year-old male presented with intraparenchymal hemorrhage in the mesencephalic tectum and left posterior thalamus. Conventional angiography revealed a left superior collicular AVM with a nidus of 3 mm. The AVM was successfully embolized but follow-up angiography examinations at 36 months demonstrated a small re-growth of the AVM (Abstract P-017 figure 1A). The patient was thus referred to radiosurgery. Thin slice contrast and non-contrast MRI acquired for target delineation did not show the AVM nidus. Therefore, the patient was transferred to the angiography suite for high resolution contrast-enhanced CBCT. Data was acquired using the angiography c-arm system with a reduced detector size of 22 cm. Contrast was injected with 2 ml/s for a total of 64 ml and a 2 sec delay) using a coupled power injector into the left vertebral artery with a 5Fr catheter. Volumetric CBCT data (FOV: 70 3 mm 3 , matrix: 0.14 3 mm 3 ) was generated using a non-binned reconstruction algorithm. Lesion and nidus were visualized with CBCT. MRI, CT-simulator and CBCT data was then transferred to the radiation planning software and mutually co-registered. The nidus was delineated on CBCT data by an experienced neurointerventional radiologist for radiation therapy and dose/treatment plan was completed. Due to image registration, the target area could be directly transferred to MRI and CT data (Abstract P-0017 figure 1B). The patient received a total of 4 radiation sessions. Abstract P-017 Figure 1 Discussion and Conclusion Radiation target delineation of micro AVMs can be challenging with conventional 3D imaging techniques as their spatial resolution is relatively low for the application of visualization of the nidus. We were able to demonstrate the complementary value of high resolution contrast enhanced CBCT in radiation target delineation of a micro brain AVM. Multi-modal image registration of CBCT with MRI and CT-simulator has shown to be an effective method for radiation target delineation. Competing interests I van der Bom: None. A Wakhloo: Philips Healthcare. A Kuhn: None. L Ding: None. D Goff: None. M Gounis: None. References 1. AJNR 1995; 16 :299. 2. J Neurosurg 2002; 97 :779–84. 3. vanderBom IMJ, et al. J NeuroIntervent Surg 2011. In press. 4. Radvany MG, et al. J NeuroIntervent Surg 2011. In press.
Purpose Radiation therapy has shown to be an effective treatment of brain arteriovenous malformations (bAVMs).1 2 Target delineation is commonly performed on volumetric image data, such as MRI or CT data. However, the nidi of micro-AVMs may not be visualized adequately by these modalities due to their limited image resolution. In this report, we show a novel usage of high-resolution contrast-enhanced cone-beam computed tomography (CBCT) imaging and multi-modal image registration3 for radiation target delineation of a micro-AVM, a technique previously suggested for larger AVMs.4 Case A 42-year-old male presented with intraparenchymal hemorrhage in the mesencephalic tectum and left posterior thalamus. Conventional angiography revealed a left superior collicular AVM with a nidus of 3 mm. The AVM was successfully embolized but follow-up angiography examinations at 36 months demonstrated a small re-growth of the AVM (Abstract P-017 figure 1A). The patient was thus referred to radiosurgery. Thin slice contrast and non-contrast MRI acquired for target delineation did not show the AVM nidus. Therefore, the patient was transferred to the angiography suite for high resolution contrast-enhanced CBCT. Data was acquired using the angiography c-arm system with a reduced detector size of 22 cm. Contrast was injected with 2 ml/s for a total of 64 ml and a 2 sec delay) using a coupled power injector into the left vertebral artery with a 5Fr catheter. Volumetric CBCT data (FOV: 703 mm3, matrix: 0.143 mm3) was generated using a non-binned reconstruction algorithm. Lesion and nidus were visualized with CBCT. MRI, CT-simulator and CBCT data was then transferred to the radiation planning software and mutually co-registered. The nidus was delineated on CBCT data by an experienced neurointerventional radiologist for radiation therapy and dose/treatment plan was completed. Due to image registration, the target area could be directly transferred to MRI and CT data (Abstract P-0017 figure 1B). The patient received a total of 4 radiation sessions.Abstract P-017 Figure 1 Discussion and Conclusion Radiation target delineation of micro AVMs can be challenging with conventional 3D imaging techniques as their spatial resolution is relatively low for the application of visualization of the nidus. We were able to demonstrate the complementary value of high resolution contrast enhanced CBCT in radiation target delineation of a micro brain AVM. Multi-modal image registration of CBCT with MRI and CT-simulator has shown to be an effective method for radiation target delineation. Competing interests I van der Bom: None. A Wakhloo: Philips Healthcare. A Kuhn: None. L Ding: None. D Goff: None. M Gounis: None. References 1. AJNR 1995;16:299. 2. J Neurosurg 2002;97:779–84. 3. vanderBom IMJ, et al. J NeuroIntervent Surg 2011. In press. 4. Radvany MG, et al. J NeuroIntervent Surg 2011. In press.