El tumor de células gigantes (TCG) es una neoplasia ósea considerada benigna generalmente, aunque localmente agresiva y puede presentar recidivas. Se origina en la epífisis/metáfisis de los huesos largos, su presentación en un arco costal es rara y de ocurrir generalmente se sitúa en la porción posterior, existiendo pocos casos reportados en la porción anterior. Se presenta el caso de una paciente femenina de 40 años de edad con gran masa en el hemi-tórax derecho. Clínicamente aparentaba un tumor profundo de la mama con invasión local de la pared torácica. La detallada evaluación radiográfica reveló una lesión costal con invasión de tejidos blandos. El examen histológico mostró células gigantes. El tumor se extirpó junto con la costilla, el defecto fue reconstruido y la paciente se recuperó sin incidentes. Se concluye que el TCG de las costillas es un caso raro, pero el diagnóstico diferencial de una masa de la pared torácica anterior debe incluirlo.
Giant cell tumor (GCT) is a bone tumor usually considered benign, although locally aggressive and may recur. It originates in the epiphysis / metaphysis of the long bones. Its presentation in a costal arch is rare and if it occurs it is usually located in the posterior portion. There are very few cases reported in the anterior portion of the costal arches. The case of a 40-year-old female patient is presented with large mass in the right hemi-thorax. Clinically it appeared a deep tumor of the breast with local invasion of the thoracic wall. The detailed radiographic evaluation revealed that the mass was a costal lesion with soft tissue invasion. Histological examination of the biopsy sample showed giant cells. The tumor was removed along with the rib. The defect was reconstructed and the patient recovered without incident. It is concluded that it is a case of GCT originating in the anterior arch of a rib with dimensions between the two largest reported in the specialized literature. It is a rare case, but the differential diagnosis of a mass of the anterior chest wall should include GCT of the ribs.