International journal of radiation oncology, biology, physics
-
Int. J. Radiat. Oncol. Biol. Phys. · Jan 2000
Clinical TrialImproving the dosimetric coverage of interstitial high-dose-rate breast implants.
We performed a retrospective computed tomography (CT)-based three-dimensional (3D) dose-volume analysis of high-dose-rate (HDR) interstitial breast implants to evaluate the adequacy of lumpectomy cavity coverage, and then designed a simple, reproducible algorithm for dwell-time adjustment to correct for underdosage of the lumpectomy cavity. ⋯ Lumpectomy cavity coverage sometimes appears suboptimal with interstitial HDR breast brachytherapy using our current technique. A simple dwell-time increase at only 1-3 dwell positions can compensate for some underdosage without creating significant regions of overdosage. Using simple methodology, a single reference point representing the underdosed region can be utilized for initial selection of the dwell positions to be increased.
-
Int. J. Radiat. Oncol. Biol. Phys. · Jan 2000
Comparative StudyThe significance of extracapsular extension of axillary lymph node metastases in early-stage breast cancer.
To investigate if extracapsular extension (ECE) of axillary lymph node metastases predicts for a decreased rate of disease-free survival or an increased rate of regional recurrence of breast carcinoma. ⋯ In this population of patients with nodal involvement, the presence of ECE correlates with the number of involved LN but does not appear to add predictive power to models of local, regional, or distant recurrence when the number of positive LN is included.
-
Int. J. Radiat. Oncol. Biol. Phys. · Jan 2000
Seed fixity in the prostate/periprostatic region following brachytherapy.
Although postoperative dosimetric analyses of prostate brachytherapy are commonly reported, the long-term persistence, or fixity, of seeds implanted in the prostate gland and periprostatic region remains unclear, with only a few reports regarding the loss or migration of the seeds in the implanted region and none which correlate lung embolization to pelvic seed loss. ⋯ With a median follow-up of 9 months, 125I seeds embedded in a vicryl suture or 103Pd seeds can be safely implanted in the prostate and periprostatic tissue with a high probability of prostate bed seed fixity and a low incidence of radioactive seed embolization to the lungs.
-
Int. J. Radiat. Oncol. Biol. Phys. · Jan 2000
Case Reports Comparative StudyThe potential for sparing of parotids and escalation of biologically effective dose with intensity-modulated radiation treatments of head and neck cancers: a treatment design study.
Conventional radiotherapy for cancers of the head and neck (HN) can yield acceptable locoregional tumor control rates, but toxicity of many normal tissues limits our ability to escalate dose. Xerostomia represents one of the most common complications. The purpose of this study is to investigate the potential of intensity-modulated radiotherapy (IMRT) to achieve adequate sparing of parotids and to escalate nominal and/or biologically-effective dose to achieve higher tumor control without exceeding normal tissue tolerances. ⋯ IMRT has the potential to significantly improve radiotherapy of HN cancers by reducing normal tissue dose and simultaneously allowing escalation of dose. SIB strategy is not only more efficient and yields better dose distributions, but may also be biologically more effective. Dose-volume-based criteria is better than purely dose-based criteria. The quality of plans improves with number of beams, reaching a saturation level for a certain number of beams, which for the plans studied was found to be 9.
-
Int. J. Radiat. Oncol. Biol. Phys. · Jan 2000
Local control and overall survival in atypical meningioma: a retrospective study.
To evaluate local control and overall survival after primary surgery for patients with atypical meningiomas. ⋯ In patients with atypical meningiomas, gross total resection is associated with a lower recurrence rate than in subtotal resection.