International journal of radiation oncology, biology, physics
-
Int. J. Radiat. Oncol. Biol. Phys. · Jun 2002
Intrafraction prostate motion during IMRT for prostate cancer.
Although the interfraction motion of the prostate has been previously studied through the use of fiducial markers, CT scans, and ultrasound-based systems, intrafraction motion is not well documented. In this report, the B-mode, Acquisition, and Targeting (BAT) ultrasound system was used to measure intrafraction prostate motion during 200 intensity-modulated radiotherapy (IMRT) sessions for prostate cancer. ⋯ Using an ultrasound-based system, intrafraction prostate motion occurred predominantly in the anterior and superior directions, but was clinically insignificant. Intrafraction motion was much smaller than interfraction motion, and the two types of movement did not correlate.
-
Int. J. Radiat. Oncol. Biol. Phys. · Jun 2002
Effect of prostatic edema on CT-based postimplant dosimetry.
To investigate the magnitude of edema after prostate brachytherapy and its effect on the CT-based postimplant dosimetry based on the sequential CT scans using dose-volume histograms, dose conformity, and homogeneity indices in patients with prostate cancer. ⋯ The decrease in prostate volume from Day 1 to Day 28 after the implant markedly improved the prescription dose covering the prostate from 77% to 85%. Day 28 prostate volumes were still about 10% larger than the preimplant CT volumes for the 25 cases evaluated. Postimplant dosimetry using dose conformity and homogeneity indices is dependent on the timing of CT studies, as a result of changing prostate volumes from edema.
-
Int. J. Radiat. Oncol. Biol. Phys. · Jun 2002
Data from a professional society placement service as a measure of the employment market for radiation oncologists.
To aid in understanding the employment market for radiation oncologists, we present annual data for 1991 to 2000 from the American College of Radiology's placement service, the Professional Bureau. This data series is twice as long as any previously available. Secondarily, we compare these data with other data on the employment market. ⋯ The employment market for radiation oncologists weakened in the first half of the 1990s, as had been widely reported; we present the first systematic data showing this. Data from a professional society placement service provide useful and inexpensive information on the employment market.
-
To study and report 6 patients with radiation recall in unique sites, secondary to gemcitabine chemotherapy. ⋯ Radiation recall from gemcitabine chemotherapy is rare, but can potentially arise in any site that has been previously irradiated. Treating physicians must be aware of this potential toxicity from gemcitabine and radiation and discontinue the gemcitabine if radiation recall is observed.
-
Int. J. Radiat. Oncol. Biol. Phys. · Jun 2002
Concomitant chemoirradiation for stage III-IV nasopharyngeal carcinoma in Chinese patients: results of a matched cohort analysis.
To evaluate the toxicity and efficacy of concomitant chemoirradiation (CRT) followed by adjuvant chemotherapy compared with radiotherapy (RT) alone in Chinese patients with locoregionally advanced nasopharyngeal carcinoma (NPC). ⋯ Our experience indicates that concomitant CRT improves locoregional control in Chinese patients with locoregionally advanced NPC, but our analyses failed to detect any impact on distant failure and survival. The failure to reduce distant metastasis and improve survival may have related in part to the more advanced disease stage in our patients and the relatively low compliance rate of adjuvant chemotherapy. Our findings suggest caution should be exercised in extrapolating the findings of the Intergroup Study 0099 to Chinese patients, and confirmatory results from prospective randomized studies in the endemic population are needed.