RESUMEN
BACKGROUND: As stereotactic body radiotherapy (SBRT) is a highly dose-dense radiotherapy, adverse events of neighboring normal tissues are a major concern. This study thus aimed to clarify the frequency and degree of clinical symptoms in patients with rib fractures after SBRT for primary lung cancer and to reveal risk factors for rib fracture. Appropriate α/ß ratios for discriminating between fracture and non-fracture groups were also investigated. METHODS: Between November 2001 and April 2009, 177 patients who had undergone SBRT were evaluated for clinical symptoms and underwent follow-up thin-section computed tomography (CT). The time of rib fracture appearance was also assessed. Cox proportional hazard modeling was performed to identify risk factors for rib fracture, using independent variables of age, sex, maximum tumor diameter, radiotherapeutic method and tumor-chest wall distance. Dosimetric details were analyzed for 26 patients with and 22 randomly-sampled patients without rib fracture. Biologically effective dose (BED) was calculated with a range of α/ß ratios (1-10 Gy). Receiver operating characteristics analysis was used to define the most appropriate α/ß ratio. RESULTS: Rib fracture was found on follow-up thin-section CT in 41 patients. The frequency of chest wall pain in patients with rib fracture was 34.1% (14/41), and was classified as Grade 1 or 2. Significant risk factors for rib fracture were smaller tumor-chest wall distance and female sex. Area under the curve was maximal for BED at an α/ß ratio of 8 Gy. CONCLUSIONS: Rib fracture is frequently seen on CT after SBRT for lung cancer. Small tumor-chest wall distance and female sex are risk factors for rib fracture. However, clinical symptoms are infrequent and generally mild. When using BED analysis, an α/ß ratio of 8 Gy appears most effective for discriminating between fracture and non-fracture patients.
Asunto(s)
Adenocarcinoma/cirugía , Neoplasias Pulmonares/cirugía , Traumatismos por Radiación/epidemiología , Radiocirugia/efectos adversos , Fracturas de las Costillas/epidemiología , Adenocarcinoma del Pulmón , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Dolor en el Pecho/epidemiología , Edema/epidemiología , Femenino , Humanos , Japón/epidemiología , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Proyectos Piloto , Valor Predictivo de las Pruebas , Prevalencia , Modelos de Riesgos Proporcionales , Curva ROC , Dosis de Radiación , Traumatismos por Radiación/diagnóstico por imagen , Fracturas de las Costillas/diagnóstico por imagen , Factores de Riesgo , Factores Sexuales , Factores de Tiempo , Tomografía Computarizada por Rayos XRESUMEN
PURPOSE: To investigate prognostic and risk factors for recurrence after stereotactic body radiation therapy (SBRT) in patients with stage I non-small cell lung carcinoma (NSCLC), focusing on dual time point [18]F-fluorodeoxyglucose positron emission tomography (FDG PET). MATERIALS AND METHODS: We prospectively evaluated 57 patients with stage I NSCLC (45 T1N0M0 and 12 T2N0M0) who had undergone pretreatment FDG-PET/CT and were subsequently treated with SBRT. All patients received a whole-body PET/CT scan at 60 min and a whole-lung at 120 min after the injection. The maximum standardized uptake value (SUV) and retention index (RI) of the lesions were calculated. Local recurrence, regional lymph node metastasis, distant metastasis, and the recurrence pattern were evaluated. Cox proportional hazard regression analyses were performed to evaluate prognostic factors or risk factors of recurrence. RESULTS: During the median follow-up period of 27 months, local recurrence, regional lymph node metastasis, and distant metastasis were seen in 17 (30%), 12 (21%), and 17 (30%) of the 57 patients, respectively. The 3-year overall survival rate was 63.4%. SUVmax did not affect any recurrence, DFS, OS, or CSS. RI significantly predicted higher distant metastasis (HR 47.546, p=0.026). In contrast, RI tended to predict lower local recurrence (HR 0.175, p=0.246) and regional lymph node metastasis (HR 0.109, p=0.115). CONCLUSIONS: SUVmax at staging FDG-PET does not predict any recurrence, DFS, OS or CSS. In contrast, higher RI predicts higher distant metastasis and tended to predict lower local or regional lymph node metastasis.
Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/cirugía , Imagen Multimodal/métodos , Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/prevención & control , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Adulto , Anciano , Femenino , Fluorodesoxiglucosa F18 , Humanos , Masculino , Persona de Mediana Edad , Radiofármacos , Radiocirugia , Reproducibilidad de los Resultados , Factores de Riesgo , Sensibilidad y Especificidad , Resultado del TratamientoRESUMEN
BACKGROUND: Chest wall injury after stereotactic radiotherapy (SRT) for primary lung cancer has recently been reported. However, its detailed imaging findings are not clarified. So this study aimed to fully characterize the findings on computed tomography (CT), appearance time and frequency of chest wall injury after stereotactic radiotherapy (SRT) for primary lung cancer MATERIALS AND METHODS: A total of 177 patients who had undergone SRT were prospectively evaluated for periodical follow-up thin-section CT with special attention to chest wall injury. The time at which CT findings of chest wall injury appeared was assessed. Related clinical symptoms were also evaluated. RESULTS: Rib fracture was identified on follow-up CT in 41 patients (23.2%). Rib fractures appeared at a mean of 21.2 months after the completion of SRT (range, 4-58 months). Chest wall edema, thinning of the cortex and osteosclerosis were findings frequently associated with, and tending to precede rib fractures. No patients with rib fracture showed tumors > 16 mm from the adjacent chest wall. Chest wall pain was seen in 18 of 177 patients (10.2%), of whom 14 patients developed rib fracture. No patients complained of Grade 3 or more symptoms. CONCLUSION: Rib fracture is frequently seen after SRT for lung cancer on CT, and is often associated with chest wall edema, thinning of the cortex and osteosclerosis. However, related chest wall pain is less frequent and is generally mild if present.
Asunto(s)
Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/radioterapia , Radiocirugia/métodos , Tomografía Computarizada por Rayos X/métodos , Anciano , Anciano de 80 o más Años , Dolor en el Pecho , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Osteosclerosis/etiología , Osteosclerosis/patología , Traumatismos por Radiación , Fracturas de las Costillas , Pared Torácica/efectos de la radiaciónRESUMEN
PURPOSE: The aim of this study was to determine a standard deviation (SD) that most reduces the radiation dose without sacrificing the diagnostic accuracy of thin-section computed tomography (CT) for clinical use. MATERIALS AND METHODS: A total of 120 patients were examined by multidetector CT. They were assigned to one of four SD groups: 8, 9, 11, and 12. Each SD group consisted of 30 patients. The CT images of the same patients with SD10 that had formerly been examined were used for comparison. Two radiologists independently evaluated the degrees of image noise and diagnostic acceptability of the pulmonary diseases using a point score grading system. We compared the scores between each SD and the SD10 group. RESULTS: Generally, image noise was significantly more prominent in the higher-SD groups. The mean score of diagnostic acceptability was significantly lower in the SD12 group (4.2 ± 1.6) than in the SD10 group (4.6 ± 1.1) group (P < 0.001), whereas no difference was present between the SD8 (4.9 ± 0.7), SD9 (4.8 ± 1.0), and SD11 (4.4 ± 1.5) groups and the SD10 group (4.7 ± 1.1, 4.6 ± 1.4, 4.6 ± 1.1, respectively). CONCLUSION: Thin-section CT with SD12 is not acceptable. SD11 seems to be the setting with the lowest radiation dose while providing acceptable imaging quality for pulmonary thin-section CT.
Asunto(s)
Enfermedades Pulmonares/diagnóstico por imagen , Dosis de Radiación , Protección Radiológica/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Femenino , Humanos , Yohexol , Masculino , Persona de Mediana Edad , Interpretación de Imagen Radiográfica Asistida por Computador , Estadísticas no ParamétricasRESUMEN
PURPOSE: The aim of this study was to evaluate thinsection computed tomography (CT) and fluorodeoxyglucose positron emission tomography (FDG-PET) findings of localized pulmonary mucinous bronchioloalveolar carcinomas (BACs). METHODS AND MATERIALS: From February 2000 to February 2009, there were seven patients with pulmonary localized mucinous BACs that were pathologically confirmed in the surgical specimens. Their CT findings were assessed regarding location, extent (percent) of groundglass opacity (GGO), margin characteristics, and the presence of air-containing spaces and contractive changes. We evaluated the presence of the "angiogram sign" in the patients who underwent enhanced CT. The maximum standardized uptake value (SUVmax) on FDG-PET was measured in four cases. RESULTS: All tumors were located in the lower lobes. The percentages of GGOs ranged from 0% to 70% (average 20%). The tumor margins were well defined in five cases and ill-defined in two cases. Air-containing spaces were seen in all cases. Evidence of contractive change was seen in two of the seven cases. The angiogram sign was identified in one of five patients who underwent enhanced CT. The SUVmax on FDG-PET ranged from 0.93 to 1.97 (mean 1.53). CONCLUSION: The imaging features of localized mucinous BACs include solid or partly solid attenuation, the presence of air-containing spaces, lack of contractive changes, and lower lobe predominance. Additionally, the SUVmax is markedly low on FDG-PET.