RESUMEN
PURPOSE: Radiosurgery (SRS) is an effective treatment option for brain metastases (BMs). Long-term results of the first worldwide experience with a mono-isocentric, non-coplanar, linac-based stereotactic technique in the treatment of multiple BMs are reported. METHODS: patients with multiple BMs, life expectancy > 3 months, and good performance status (≤ 2) were treated with simultaneous SRS with volumetric modulated arc technique. Data were retrospectively evaluated. RESULTS: 172 patients accounting for 1079 BMs were treated at our institution from 2017 to 2020. The median number of treated metastases was 4 (range 2-22). Primary tumor histology was: lung (44.8%), breast (32%), and melanoma (9.4%). The 2-year LPFS was 71.6%, respectively. A biological effective dose (BED) ≥ 51.3 Gy10 correlated with higher local control. Uncontrolled systemic disease and melanoma histology were independent prognostic factors correlated with decreased iPFS. Patients with > 10 BMs had a trend towards shorter iPFS (p = 0.055). 31 patients received multiple SRS courses (2-7) in case of intracranial progression. The median iOS was 22.4 months. Brainstem metastases and total PTV > 7.1 cc correlated with shorter iOS. The 1- and 2-year WBRT-free survival was 83.2% and 61.1%, respectively. CONCLUSION: Long-term results in a large patient population treated with a mono-isocentric, dedicated technique demonstrated its effectiveness and safety also in the case of multiple courses. The shortened treatment time and the possibility to safely spare healthy brain tissue allows the safe treatment of patients with a large number of metastases and to deliver multiple courses of SRS. In selected cases, the administration of WBRT can be delayed.
Asunto(s)
Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundario , Irradiación Craneana/métodos , Radiocirugia/métodos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/mortalidad , Neoplasias de la Mama/patología , Estudios de Cohortes , Irradiación Craneana/efectos adversos , Irradiación Craneana/instrumentación , Femenino , Humanos , Estimación de Kaplan-Meier , Neoplasias Pulmonares/patología , Masculino , Melanoma/radioterapia , Melanoma/secundario , Persona de Mediana Edad , Recurrencia Local de Neoplasia/radioterapia , Órganos en Riesgo/efectos de la radiación , Supervivencia sin Progresión , Traumatismos por Radiación/prevención & control , Radiocirugia/efectos adversos , Radiocirugia/instrumentación , Dosificación Radioterapéutica , Efectividad Biológica Relativa , Estudios Retrospectivos , Factores de Tiempo , Resultado del TratamientoRESUMEN
PURPOSE: To analyze clinical-dosimetric predictors of genitourinary (GU) toxicity in a cohort of prostate cancer (PC) patients treated with moderate hypofractionation and simultaneous integrated boost (SIB) using volumetric modulated arc therapy (VMAT) technique. MATERIALS AND METHODS: 60 patients were selected. Patients were stratified into low (43 %), intermediate (30 %) and high-risk (27 %) groups. Low-risk patients received 73.5 Gy to PTV1; intermediate-risk received 73.5 Gy to PTV1 and 60 Gy to PTV2; high-risk received 73.5 Gy to PTV1, 60 Gy to PTV2, and 54 Gy to PTV3. All patients were treated in 30 fractions. Androgen deprivation therapy (ADT) was prescribed upfront in intermediate and high-risk categories. Toxicity was scored according to Common Terminology Criteria for Adverse Events v4.0 scoring system. RESULTS: Median follow-up was 30 months (range 16-36 months). GU acute toxicity was recorded as followS: G0 = 16/60 (27 %), G1 = 18/60 (30 %); G2 = 26/60 (43 %). GU late toxicity was recorded as follows: G0 = 20/60 (34 %); G1 = 29/60 (48 %); G2 = 11/56 (18 %). The risk of acute G2 GU toxicity was three times higher for prostate volume ≥80 cc. In 60 % of the patients with a prostate volume ≥80 cc, the first 3 weeks are at particular risk for toxicity onset. In the late setting, no statistical significance was found between GU toxicity and prostate gland dimension. CONCLUSION: Prostate volume ≥80 cc resulted a predictive factor of acute G2 GU toxicity, in moderate hypofractionation and volumetric modulated arc radiation therapy for definitive PC.
Asunto(s)
Adenocarcinoma/radioterapia , Órganos en Riesgo/efectos de la radiación , Próstata , Neoplasias de la Próstata/radioterapia , Radioterapia de Intensidad Modulada/efectos adversos , Sistema Urogenital/efectos de la radiación , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Humanos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Hipofraccionamiento de la Dosis de Radiación , Traumatismos por Radiación/etiología , Dosificación RadioterapéuticaRESUMEN
The three-dimensional architecture of the vascular network of the nasal septum of the gerbil rat was studied using the corrosive resin cast technique. The angioarchitecture of the nasal septum observed with scanning electron microscopy (SEM) showed that a vascular network is disposed in the lamina propria. The capillaries, arterioles, venules and arteries were closely observed in different areas of the nasal septum mucosa.