ABSTRACT
Exponemos el caso de una mujer de 55 años, con antecedentes de melanoma en cara interna de pierna izquierda, años atrás. Tras golpe en dicha zona, aparece nodulación que se biopsia e identifica como metástasis de melanoma. Para valorar la extensión de la enfermedad, se realiza PET-FDG, donde se identifican tres hallazgos patológicos; dos de ellos sugestivos de malignidad y un tercero de posible origen osteoarticular. Para su exacta localización y complementar imágenes PET-FDG, se realiza RNM de cuerpo completo. Sus hallazgos son coincidentes con los del estudio PET, permitiéndonos determinar que el foco hipermetabólico PET, probablemente osteoarticular, no se corresponde con alteración articular alguna, sino en porción inferior del tejido infra-rotuliano. Resaltamos la importancia de complementar la PET-FDG con RNM de cuerpo completo frente a complementar con TAC, cuando las localizaciones de focos patológicos PET se sitúen en zonas donde la RNM presente mayor sensibilidad que la TAC.
We present a case of 55 years old woman with antecedents of left leg melanoma, several years ago. After a strike in that area, a node appeared; this one was biopsed and identified as melanoma metastasis. To value the bodily extension of the disease, a PET-FDG was performed. There were three pathologic findings; two were suggestive of malignancy and the third one had a possible ostheoarticular origin. In order to have an exact localization of the lesions and to complement PET-FDG images, a whole body MRI was performed. Its findings coincide with PET findings, allowing determine that the hypermetabolic focus from PET, probably ostheoarticular, doesn´t correspond with articular alteration, but it was in lower infrapatellar tissue. We emphasize the importance of PET-FDG complement with whole-body MRI in front of to complement with CT, when the pathologic focus localizations in PET are in areas where MRI presents upper sensibility than CT.