International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2009
Gamma Knife radiosurgery for brain metastases from primary breast cancer.
The relative roles of stereotactic radiosurgery (SRS) vs. whole brain radiotherapy (WBRT) in the treatment of patients with brain metastases from breast cancer remain undefined. In this study, we reviewed our experience with these patients. ⋯ We have described prognostic factors for breast cancer patients treated with SRS for newly diagnosed or recurrent brain metastases. Most patient subsets had a median survival time of >or=11 months. Unexpectedly, upfront WBRT did not appear to improve brain freedom from progression, and a larger number of brain metastases was not associated with a shorter survival time. Breast cancer might be distinct from other primary sites in terms of prognostic factors and the roles of WBRT and SRS for brain metastases.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2009
Ductal carcinoma in situ of the breast with close or focally involved margins following breast-conserving surgery: treatment with reexcision or radiotherapy with increased dosage.
Following breast-conserving surgery for DCIS, reexcision before radiotherapy is recommended when margins are close or involved. We investigated whether an additional radiation dose could replace reexcision. ⋯ In carefully selected patients with close (< 2 mm) or focally/minimally involved margins, reexcision may be avoided and satisfactory local control achieved by increasing the radiation dose to the tumour bed to at least 66 Gy. These results only apply to patients older than 40 and would need confirmation in independent series.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2009
Predicting likelihood of having four or more positive nodes in patient with sentinel lymph node-positive breast cancer: a nomogram validation study.
Katz suggested a nomogram for predicting having four or more positive nodes in sentinel lymph node (SLN)-positive breast cancer patients. The findings from this formula might influence adjuvant radiotherapy decisions. Our goal was to validate the accuracy of the Katz nomogram. ⋯ The probability of four or more involved nodes is significantly greater in patients who have an increased number of positive SLNs, increased overall metastasis size, increased tumor size, and extracapsular extension. The Katz nomogram was validated in our patients. This nomogram will be helpful to clinicians making adjuvant treatment recommendations to their patients.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2009
Dosimetric study of pelvic proton radiotherapy for high-risk prostate cancer.
To compare dose distributions in targeted tissues (prostate, seminal vesicles, pelvic regional nodes) and nontargeted tissues in the pelvis with intensity-modulated radiotherapy (IMRT) and forward-planned, double-scattered, three-dimensional proton radiotherapy (3D-PRT). ⋯ Use of 3D-PRT significantly reduced the dose to normal tissues in the pelvis while maintaining adequate target coverage compared with IMRT or IMRT/3D-PRT. When treating the prostate, seminal vesicles, and pelvic lymph nodes in prostate cancer, proton therapy may improve the therapeutic ratio beyond what is possible with IMRT.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2009
Quantifying interfraction and intrafraction tumor motion in lung stereotactic body radiotherapy using respiration-correlated cone beam computed tomography.
Stereotactic body radiation therapy (SBRT) is an effective treatment for medically inoperable Stage I non-small-cell lung cancer. However, changes in the patient's breathing patterns during the course of SBRT may result in a geographic miss or an overexposure of healthy tissues to radiation. However, the precise extent of these changes in breathing pattern is not well known. We evaluated the inter- and intrafractional changes in tumor motion amplitude (DeltaM) over an SBRT course. ⋯ The inter- and intrafractional DeltaM that occur during a course of lung SBRT are small. However, abdominal compression causes larger variations in the time spent on the treatment couch and in the inter- and intrafractional DeltaM values.