International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · May 1996
Clinical TrialConcurrent cisplatin, etoposide, and radiotherapy for unresectable stage III nonsmall cell lung cancer: a phase II study.
Prognosis of unresectable Stage III nonsmall cell lung cancer (NSCLC) treated with thoracic radiotherapy alone has been disappointing. In recent years, several Phase III trials have demonstrated encouraging results with induction chemotherapy, but with poor long-term local control. Concurrent cisplatin alone during the radiation therapy course has resulted in improved local control, but without efficacy on occult metastatic disease. Intensification of chemotherapy during radiation has the potential of improving both local control and metastasis-free survival. This Phase II study was undertaken to determine the feasibility, toxicity, response rate, local control, and survival of concurrent chemotherapy with cisplatin-etoposide and radiotherapy in unresectable Stage IIIA and IIIB nonsmall cell lung cancer. ⋯ Concomitant chemoradiotherapy with cisplatin and etoposide at this dose level is a well tolerated outpatient regimen, which resulted in a high local control rate, and an encouraging survival at 1, 2, and 3 years. A direct comparison of this treatment schedule to induction chemotherapy followed by radiotherapy, or concurrent chemoradiation therapy using cisplatin alone, appears warranted.
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Int. J. Radiat. Oncol. Biol. Phys. · May 1996
Lateral rectal shielding reduces late rectal morbidity following high dose three-dimensional conformal radiation therapy for clinically localized prostate cancer: further evidence for a significant dose effect.
Using conventional treatment methods for the treatment of clinically localized prostate cancer central axis doses must be limited to 65-70 Gray (Gy) to prevent significant damage to nearby normal tissues. A fundamental hypothesis of three-dimensional conformal radiation therapy (3DCRT) is that, by defining the target organ(s) accurately in three dimensions, it is possible to deliver higher doses to the target without a significant increase in normal tissue complications. This study examines whether this hypothesis holds true and whether a simple modification of treatment technique can reduce the incidence of late rectal morbidity in patients with prostate cancer treated with 3DCRT to minimum planning target volume (PTV) doses of 71-75 Gy. ⋯ The incidence of late rectal morbidity with 3DCRT to minimum PTV doses of 71-75 Gy is acceptable and to date no Grade 4-5 rectal morbidities have been observed. In our experience, higher doses to the center of the prostate are associated with an increased likelihood of developing Grade 2-3 rectal morbidity but treatment techniques that reduce the total dose to the anterior rectal wall have reduced the incidence of late rectal morbidity. If clinical studies indicate improved tumor control with minimum PTV doses above 71 Gy, then dose escalation above 76 Gy to the center of the prostate should be pursued cautiously with treatment techniques that limit the total dose to the anterior rectal wall.
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Int. J. Radiat. Oncol. Biol. Phys. · May 1996
Analysis of localization errors in the definition of the mantle field using a beam's eye view treatment-planning system.
Reports of the treatment of Hodgkin's disease (HD) with radiotherapy using the mantle field technique have demonstrated that coverage of disease by the field blocks significantly compromises outcome. It is our hypothesis that the availability of computerized tomography images reduces the incidence of localization error, and that the use of beam's eye view treatment planning techniques may further improve localization. The purpose of this report is to assess the possible contribution of a three-dimensional treatment-planning system to tumor localization and mantle block drawing in patients with HD. ⋯ The availability of CT imaging offers an advantage in the outlining of the mantle field in the treatment of Hodgkin's disease. When the error rate is evaluated using a beam's eye view treatment planning system, a significant proportion of tumors may be overlapped by the outlined mantle blocks even when CT images are available for reference. The use of beam's eye view treatment planning in mantle field definition, especially for tumors in the axillary region, may reduce the incidence of geographic misses.