RESUMEN
BACKGROUND: To achieve a more specific method to estimate the real size of breast cancer, we have developed a method to fuse magnetic resonance imaging (MRI) and scintimammography (SM) images. The aim of this study was to assess the feasibility of this method and to evaluate its accuracy to measure the size of breast cancer compared with MRI alone, mammography, and clinical examination, employing pathologic size as the gold standard. METHODS: Twenty consecutive breast cancer women at stages IIA-IIIA, scheduled for mastectomies, underwent SM with (99m)Tc-sestamibi and MRI with gadolinium 2-10 days before surgery. All patients had had recent mammographies and were examined clinically. Software was developed in visual language to perform the fusion between MRI and SM images and tumor measurements (MRI/SM). The tumor size, in 3 diameters (anteroposterior, longitudinal, and transverse), for each examination was correlated with pathological measurements using linear regression. RESULTS: The MRI/SM technique was successfully performed in all patients, and the principal tumor was measured by this method. The MRI/SM cancer measurements correlated better with pathology than MRI, mammography, and clinical exam in all diameters analyzed (r = 0.88, 0.81, 0.81; SE = 0.11, 0.14, 0.11 in anteroposterior, longitudinal, and transverse diameters, respectively). CONCLUSIONS: The MRI/SM is a feasible technique and appears to be more accurate than other examinations (MRI alone, mammography, and clinical exam) to measure breast cancer size.
Asunto(s)
Neoplasias de la Mama/diagnóstico , Carcinoma Ductal de Mama/diagnóstico , Aumento de la Imagen/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Mamografía/métodos , Cintigrafía/métodos , Adulto , Anciano , Mama/patología , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/patología , Carcinoma Ductal de Mama/cirugía , Estudios de Factibilidad , Femenino , Humanos , Mastectomía , Persona de Mediana Edad , Estadificación de Neoplasias , Proyectos Piloto , Sensibilidad y Especificidad , Programas Informáticos , Tecnecio Tc 99m SestamibiRESUMEN
The purpose of this study was to evaluate the feasibility of surgery radioguided with intravenous (99m)Tc sestamibi associated with magnetic resonance imaging (MRI) of the breast to detect tumor extent and guide complete tumor resection. A descriptive experimental study was developed with 10 breast cancer patients (stage IIA-IIB) who underwent mastectomy. From 2 to 10 days before surgery, the patients underwent breast MRI with 0.1 mmol/kg of gadolinium and scintimammography with a 740 MBq of (99m)Tc sestamibi. A region of interest was drawn around the tumor image and an uptake curve as a function of time was plotted to calculate the optimal time to perform radioguided surgery. In the perioperative period, the same dose of (99m)Tc sestamibi was intravenously injected into the patients. Tumor resection was performed under the guidance of a gamma probe. MRI was used to evaluate the skin and deep fascia involvement and to detect occult tumor foci which were also excised. Subsequently a modified radical mastectomy was performed. Tumor and residual breast were histopathologically examined. In a series of 10 women, all demonstrated (99m)Tc sestamibi uptake in tumor cells. Eight patients showed no disease in the residual breast, one presented with one foci of invasive ductal carcinoma measuring 0.5 cm in diameter located 5 cm from the tumor bed, and one presented with one foci of ductal carcinoma in situ measuring 0.8 cm at the resection margin. The mean tumor size in the histopathologic assessment was 3.3 cm and in MRI was 5.0 cm. Radioguided surgery using (99m)Tc sestamibi associated with MRI is a feasible technique that can be employed in tumor resection.
