International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Feb 2012
Comparative StudyOn the benefits and risks of proton therapy in pediatric craniopharyngioma.
Craniopharyngioma is a pediatric brain tumor whose volume is prone to change during radiation therapy. We compared photon- and proton-based irradiation methods to determine the effect of tumor volume change on target coverage and normal tissue irradiation in these patients. ⋯ Compared with photon IMRT, proton therapy has the potential to significantly reduce whole-brain and -body irradiation in pediatric patients with craniopharyngioma. IMPT is the most conformal method and spares the most normal tissue; however, it is highly sensitive to target volume changes, whereas the DSP method is not.
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Int. J. Radiat. Oncol. Biol. Phys. · Feb 2012
Tumor volume reduction rate after preoperative chemoradiotherapy as a prognostic factor in locally advanced rectal cancer.
To investigate the prognostic significance of tumor volume reduction rate (TVRR) after preoperative chemoradiotherapy (CRT) in locally advanced rectal cancer (LARC). ⋯ Tumor volume reduction rate was a significant prognostic factor in LARC patients receiving preoperative CRT. Tumor volume reduction rate data may be useful for tailoring surgery and postoperative adjuvant therapy after preoperative CRT.
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Int. J. Radiat. Oncol. Biol. Phys. · Feb 2012
Hypofractionated concomitant intensity-modulated radiotherapy boost for high-risk prostate cancer: late toxicity.
To report the acute and late toxicities of patients with high-risk localized prostate cancer treated using a concomitant hypofractionated, intensity-modulated radiotherapy boost combined with long-term androgen deprivation therapy. ⋯ A hypofractionated intensity-modulated radiotherapy boost delivering 67.5 Gy in 25 fractions within 5 weeks combined with pelvic nodal radiotherapy and long-term androgen deprivation therapy was well tolerated, with low rates of severe toxicity. The biochemical control rate at early follow-up has been promising. Additional follow-up is needed to determine the long-term biochemical control and prostate biopsy results.
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Int. J. Radiat. Oncol. Biol. Phys. · Feb 2012
Comparative StudyIntensity-modulated arc therapy for pediatric posterior fossa tumors.
To compare intensity-modulated arc therapy (IMAT) to noncoplanar intensity-modulated radiation therapy (IMRT) in the treatment of pediatric posterior fossa tumors. ⋯ Noncoplanar IMAT results in superior treatment plans when compared to noncoplanar IMRT for the treatment of posterior fossa tumors. IMAT should be considered alongside IMRT when treatment of this site is indicated.
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Int. J. Radiat. Oncol. Biol. Phys. · Feb 2012
Predicting pelvic lymph node involvement in current-era prostate cancer.
The Roach formula [2/3 × prostate-specific antigen + (Gleason score--6) × 10], derived in 1993 during the early prostate specific antigen (PSA) screening era, has been used to predict the risk of pelvic lymph node involvement in patients with prostate cancer. In the current era of widespread PSA screening with a shift to earlier disease stages, there is evidence to suggest that the Roach score overestimates risk of nodal metastasis. This study retrospectively reviews the validity of this formula as a prediction tool. ⋯ The Roach formula overpredicts the risk of pelvic nodal involvement in current-era prostate cancer patients undergoing regular PSA screening and with mainly T1c/T2 disease. Contemporary patients are much less likely to have nodal involvement for a given PSA and Gleason score.