International journal of radiation oncology, biology, physics
-
Int. J. Radiat. Oncol. Biol. Phys. · May 2003
Comparative StudyDosimetric analysis and comparison of three-dimensional conformal radiotherapy and intensity-modulated radiation therapy for patients with hepatocellular carcinoma and radiation-induced liver disease.
This study compares the difference in dose-volume data between three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) for patients with hepatocellular carcinoma (HCC) and previously documented radiation-induced liver disease (RILD) after 3D-CRT. ⋯ IMRT is capable of preserving acceptable target coverage and improving or at least maintaining the nonhepatic organ sparing for patients with HCC and previously diagnosed RILD after 3D-CRT. The true impact of this technique on the liver remains unsettled and may depend on the exact volume effect of this organ.
-
Int. J. Radiat. Oncol. Biol. Phys. · May 2003
Comparative StudyTumor location, cirrhosis, and surgical history contribute to tumor movement in the liver, as measured during stereotactic irradiation using a real-time tumor-tracking radiotherapy system.
To investigate the three-dimensional (3D) intrafractional motion of liver tumors during real-time tumor-tracking radiotherapy (RTRT). ⋯ Tumor location, cirrhosis, and history of surgery on the liver all had an impact on the intrafractional tumor motion of the liver in the transaxial direction. This finding should be helpful in determining the smallest possible margin in individual cases of radiotherapy for liver malignancy.
-
Int. J. Radiat. Oncol. Biol. Phys. · May 2003
Comparative StudyIntensity-modulated radiotherapy in nasopharyngeal carcinoma: dosimetric advantage over conventional plans and feasibility of dose escalation.
To compare intensity-modulated radiotherapy (IMRT) with two-dimensional RT (2D-RT) and three-dimensional conformal radiotherapy (3D-CRT) treatment plans in different stages of nasopharyngeal carcinoma and to explore the feasibility of dose escalation in locally advanced disease. ⋯ IMRT is useful in treating all stages of nonmetastatic nasopharyngeal carcinoma because of its dosimetric advantages. In early-stage disease, it provides better parotid gland sparing. In locally advanced disease, IMRT offers better tumor coverage and normal organ sparing and allows room for dose escalation.
-
Int. J. Radiat. Oncol. Biol. Phys. · May 2003
Comparative StudyPreliminary evaluation of low-grade toxicity with conformal radiation therapy for prostate cancer on RTOG 9406 dose levels I and II.
To evaluate the rates of low-grade late effects in patients treated for prostate cancer on Radiation Therapy Oncology Group (RTOG) 9406. ⋯ Morbidity of 3D-CRT in the treatment of prostate cancer is low. It is important to continue to closely examine late effects in patients treated in RTOG 9406. The primary objective of dose escalation without an increase rate of >/= Grade 3 sequelae has been achieved. However, the reduction in Grade 3 complications may have resulted in a higher incidence of Grade 1 or 2 late effects. Because Grade 2 late effects may have a significant impact on a patient's quality of life, it is important to reduce these complications as much as possible. Clinical trials should use quality-of-life measures to determine that trade-offs between severity and rates of toxicity are acceptable to patients.
-
Int. J. Radiat. Oncol. Biol. Phys. · May 2003
Clinical TrialTolerance of organs at risk in small-volume, hypofractionated, image-guided radiotherapy for primary and metastatic lung cancers.
To determine the organ at risk and the maximum tolerated dose (MTD) of radiation that could be delivered to lung cancer using small-volume, image-guided radiotherapy (IGRT) using hypofractionated, coplanar, and noncoplanar multiple fields. ⋯ Small-volume IGRT using 60 Gy in eight fractions is highly effective for the local control of lung tumors, but MTD has not been determined in this study. The organs at risk are extrapleural organs such as the esophagus and internal chest wall/visceral pleura rather than the pulmonary parenchyma in the present protocol setting. Consideration of the uncertainty in the contouring of normal structures is critically important, as is uncertainty in setup of patients and internal organ in the high-dose hypofractionated IGRT.