International journal of radiation oncology, biology, physics
-
Int. J. Radiat. Oncol. Biol. Phys. · Jul 2003
What hypofractionated protocols should be tested for prostate cancer?
Recent analyses of clinical results have suggested that the fractionation sensitivity of prostate tumors is remarkably high; corresponding point estimates of the alpha/beta ratio for prostate cancer are around 1.5 Gy, much lower than the typical value of 10 Gy for many other tumors. This low alpha/beta value is comparable to, and possibly even lower than, that of the surrounding late-responding normal tissue in rectal mucosa (alpha/beta nominally 3 Gy, but also likely to be in the 4-5 Gy range). This lower alpha/beta ratio for prostate cancer than for the surrounding late-responding normal tissue creates the potential for therapeutic gain. We analyze here possible high-gain/low-risk hypofractionated protocols for prostate cancer to test this suggestion. ⋯ The hypofractionated regimens that we suggest be tested for prostate-cancer radiotherapy show high potential therapeutic gain as well as economic and logistic advantages. They appear to have little potential risk as long as excessively short overall times (<5 weeks) and very small fraction numbers (<5) are avoided. The values of bNED and rectal complications presented are entirely theoretical, being related by LQ modeling to existing clinical data for approximately intermediate-risk prostate cancer patients as discussed in detail.
-
Int. J. Radiat. Oncol. Biol. Phys. · Jul 2003
Radiosurgical treatment of trigeminal neuralgia: evaluating quality of life and treatment outcomes.
To assess the safety, efficacy, and quality of life (QOL) associated with radiosurgical treatment for trigeminal neuralgia (TN). ⋯ GKRS provides significant pain relief and improves QOL in the majority of patients treated for TN, with few bothersome side effects. Patients with both temporary and sustained responses to treatment realized significant improvements in QOL after GKRS, and considered their treatment successful. Longer follow-up of these patients may reveal additional recurrences highlighting the importance of studies evaluating repeat GKRS and optimization of current treatment techniques and patient selection.
-
Int. J. Radiat. Oncol. Biol. Phys. · Jul 2003
Tolerance of tissue transfers to adjuvant radiation therapy in primary soft tissue sarcoma of the extremity.
Treatment of extremity sarcomas occasionally requires tissue transfer in the form of pedicle flaps, free flaps, or skin grafts to repair surgical defects. These tissues are often subject to radiation (RT) and are therefore at risk for wound breakdown requiring reoperation. This study reviews a single center's experience with tissue transfer and postoperative RT. METODS AND MATERIALS: Between 1983 and 2000, 43 adult patients (>16 years old) with primary high-grade soft tissue extremity sarcomas underwent limb-sparing surgery and reconstruction of their surgical defects, followed by adjuvant RT. The reconstructions were as follows: pedicle flaps (n = 14), free flaps (n = 10), skin grafts (n = 4), or a combination (n = 15). Postoperative external beam radiation therapy (EBRT) (median dose: 63 Gy) alone was given to 27 patients (63%). Adjuvant brachytherapy (BRT) was given to 16 patients (37%); BRT alone (median dose: 45 Gy) was given to 12 patients and combined with EBRT for 4 patients (EBRT: 45 Gy; BRT: 20 Gy). Comorbid conditions such as diabetes, hypertension, tobacco use, and obesity (calculated using body mass index >or=30) were present in 30 patients (70%). Tumor characteristics were as follows: 26 were >5 cm in size, 37 were deep, and 30 were in the lower extremity. The median follow-up time, calculated from the date of operation, was 32 months. Five of 43 patients suffered wound complications necessitating reoperation; however, 3 patients developed complications before initiation of RT and were therefore excluded from the analysis. Two of 43 patients (5%) required reoperation for wound complications after RT; 1 of these patients ultimately required amputation for necrosis. The 5-year overall wound reoperation rate was 6% (95% confidence interval: 0-14%). The influence of patient and tumor characteristics, as well as the type of RT, on the wound reoperation rates is as follows: BRT vs. EBRT (17% vs. 0%, p = 0.06); upper vs. lower extremity (0% vs. 8%, p = 0.41);
-
Int. J. Radiat. Oncol. Biol. Phys. · Jul 2003
Clinical TrialPhase II study of three-dimensional conformal radiotherapy and concurrent mitomycin-C, vinblastine, and cisplatin chemotherapy for Stage III locally advanced, unresectable, non-small-cell lung cancer.
To evaluate the feasibility, treatment outcome, and toxicity of hyperfractionated three-dimensional conformal radiotherapy (CRT) and concurrent mitomycin-C, vinblastine, and cisplatin (MVP) chemotherapy in locally advanced, unresectable, Stage III non-small-cell lung cancer (NSCLC). ⋯ Hyperfractionated three-dimensional CRT and concurrent chemotherapy, as described here, is a well-tolerated regimen with acceptable toxicity. More effective treatment schemes are required to improve local disease control and overall survival.
-
Int. J. Radiat. Oncol. Biol. Phys. · Jul 2003
Urinary symptom flare following I-125 prostate brachytherapy.
Although acute urinary morbidity after prostate brachytherapy has been well-documented, long-term effects have not been fully characterized. We describe a late complication of I-125 prostate brachytherapy we have termed urinary symptom flare. ⋯ Acute symptoms after I-125 prostate brachytherapy appear to peak 1 month after a prostate implant and return to their baseline values at 1 year. A transient late exacerbation of urinary symptoms is common and can occur in up to half of all patients by 5 years. There appears to be no statistically significant association between a late exacerbation in urinary symptoms and clinical or implant parameters.