RESUMEN
AIM: To investigate whether the target-isocenter deviations reported by a conventional Winston-Lutz (WL) test actually reflect the shifts of the measured prescription isodose line with respect to the target. BACKGROUND: A conventional WL test uses a metallic ball as a target that aims at several fields. But this test does not report information on the accuracy of the delivery in terms of dose. MATERIALS AND METHODS: A conventional WL test using a metallic pointer as a target (Pointer-WL test) has been recreated in the Eclipse treatment planning system over an acrylic phantom containing a radiochromic film (Dose-WL test). After Dose-WL test delivery, the shift of the 80% prescription isodose line with respect to the target center (d80%-center) was measured using film dosimetry. The Pointer-WL and Dose-WL tests were performed in 10 different sessions. The isocenter deviation reported by the Pointer-WL test was compared to the d80%-center vector, according to the three patient's directions (Left-Right or LR; Anterior-Posterior or AP; and Superior-Inferior or SI). RESULTS: The deviations (mean ± SD) found for the Dose-WL tests (LR: 0.5 ± 0.4 mm; AP: 0.5 ± 0.4 mm; SI: 0.6 ± 0.2 mm) were in most cases less than 1 mm, and they were significantly smaller (all p < 0.05) than the maximum deviations reported by the Pointer-WL tests (LR: 1.3 ± 0.3 mm; AP: 1.2 ± 0.4 mm; SI: 1.1 ± 0.3 mm). CONCLUSIONS: The Dose-WL test described in this study allows estimating the spatial accuracy of the prescription isodose line.
RESUMEN
PURPOSE: We retrospectively reviewed our Institution's database to investigate the outcome and impact of combined radiochemotherapy (RT/CT; concomitant or in sequence) in localised small-cell lung cancer (L-SCLC). MATERIAL AND METHODS: Between January 1995 to November 1999, 79 patients with L-SCLC received combined RT/CT at our Institution. RT was delivered concurrently or sequentially following the CT. Patients with treatment response received additional prophylactic cranial irradiation (PCI). RESULTS: Of the patients treated, 54% had received concurrent CT/RT compared to 46% receiving RT following the CT. PCI was administered to 80% of the patients. Complete response was observed in 66% of patients. With a median follow up of 30 months, median overall survival was 15.9 months; 14.3 months for patients who received RT following CT and 21.6 months for those receiving concurrent CT/RT. The type of schedule of combined radiochemotherapy was an independent prognostic factor for survival free of local recurrence, as was additional PCI for distant metastasis-free survival. CONCLUSIONS: Our results are similar to those reported previously in the literature. The main point of interest is that our patients were non-selected. We strongly support the use of concurrent CT/RT so as to achieve results comparable to the best in the literature.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Pequeñas/terapia , Neoplasias Pulmonares/terapia , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Células Pequeñas/tratamiento farmacológico , Carcinoma de Células Pequeñas/radioterapia , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Terapia Combinada , Irradiación Craneana , Supervivencia sin Enfermedad , Esofagitis/etiología , Etopósido/administración & dosificación , Etopósido/efectos adversos , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/radioterapia , Masculino , Persona de Mediana Edad , Neutropenia/etiología , Neumonitis por Radiación/etiología , Radioterapia/efectos adversos , Inducción de Remisión , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del TratamientoRESUMEN
Purpose. We retrospectively reviewed our Institution's database to investigate the outcome and impact of combined radiochemotherapy (RT/CT; concomitant or in sequence) in localised small-cell lung cancer (L-SCLC). Material and methods. Between January 1995 to November 1999, 79 patients with L-SCLC received combined RT/CT at our Institution. RT was delivered concurrently or sequentially following the CT. Patients with treatment response received additional prophylactic cranial irradiation (PCI). Results. Of the patients treated, 54% had received concurrent CT/RT compared to 46% receiving RT following the CT. PCI was administered to 80% of the patients. Complete response was observed in 66% of patients. With a median follow up of 30 months, median overall survival was 15.9 months; 14.3 months for patients who received RT following CT and 21.6 months for those receiving concurrent CT/RT. The type of schedule of combined radiochemotherapy was an independent prognostic factor for survival free of local recurrence, as was additional PCI for distant metastasis-free survival. Conclusions. Our results are similar to those reported previously in the literature. The main point of interest is that our patients were non-selected. We strongly support the use of concurrent CT/RT so as to achieve results comparable to the best in the literature
Purpose. We retrospectively reviewed our Institution's database to investigate the outcome and impact of combined radiochemotherapy (RT/CT; concomitant or in sequence) in localised small-cell lung cancer (L-SCLC). Material and methods. Between January 1995 to November 1999, 79 patients with L-SCLC received combined RT/CT at our Institution. RT was delivered concurrently or sequentially following the CT. Patients with treatment response received additional prophylactic cranial irradiation (PCI). Results. Of the patients treated, 54% had received concurrent CT/RT compared to 46% receiving RT following the CT. PCI was administered to 80% of the patients. Complete response was observed in 66% of patients. With a median follow up of 30 months, median overall survival was 15.9 months; 14.3 months for patients who received RT following CT and 21.6 months for those receiving concurrent CT/RT. The type of schedule of combined radiochemotherapy was an independent prognostic factor for survival free of local recurrence, as was additional PCI for distant metastasis-free survival. Conclusions. Our results are similar to those reported previously in the literature. The main point of interest is that our patients were non-selected. We strongly support the use of concurrent CT/RT so as to achieve results comparable to the best in the literature