Cirugía radioguiada: extirpación de metástasis de un carcinoma papilar de tiroides / Probe-guided surgery: metastases of a papillary thyroid carcinoma. Surgical Excision

RESUMEN

Paciente de sexo masculino operado de Carcinoma Papilar Tiroideo (variedad folicular) con recurrencia tumoral luego de tiroidectomía, linfadenectomía y Dosis Terapéutica de Iodo 131. Bajo tratamiento con hormonas tiroideas a dosis inhibitorias de TSH, persistencia de valores elevados de Tiroglobulina Plasmática e imágenes detectables en la Ecografía y Resonancia Magnética Nuclear ( RMN). Por la Dosis Terapéutica se sospechaba que las mismas concentrarían radioyodo. Se planificó por lo tanto cirugía radioguiada, según el protocolo del Instituto Gustave Roussy (modificado). Dosis Terapéutica de Iodo 131; al 4º día Rastreo Corporal Total en Cámara Gamma (RCT); al 5º día cirugía con sonda exploradora (gamma probe) y a las 48 hs. poscirugía nuevo RCT. El procedimiento fue exitoso, pudiendo extirparse adenopatías metastásicas con la desaparición en el RCT posquirúrgico de las imágenes que fijaban francamente radioyodo en el preoperatorio. Los vlores de Tiroglobulina plasmática descendieron francamente con terapia hormonal de reemplazo, a los sesenta y noventa días postratamiento.

ABSTRACT

A male patient with papillary thyroid cancer -folliculary variety- is chosen to be presented. After thyroidectomy, lymfhadenectomy and therapeutic dose of radioiodine treatments, cancer relapse was observed. After thyrotrophyn supressive therapy with l-thyroxine, a high serum thyroglobulin concentration was observed. The Ultrasonography ( US) and Magnetic Resonance (MR) images showed visible node structures in the neck. This node structures were probably going to concentrate I-131 as seen in the first whole body scan after therapeutic dose. Therefore a radio-guided surgery was planned as the best choice. (Institute Gustave Roussy protocol). A therapeutic dose of radioiodine (I-131) was given and up to the 4th day a whole body scan was performed. In the 5th day a gamma- probe-guided surgery was performed as well, and localized metastatic foci in the pretracheal region and under right recurrent laryngeal nerve. No other foci were identified with the probe at surgery. Forty eight hours after surgery a new whole-body scan was made again. The procedure was successful. The metastatic lessions were completely dissected. The last whole body scan showed that radioiodine concentration had disappeared at all. Forty five days and three months after surgery under levothyroxin treatment, the serum thyroglobulin level concentration decrease to very low values.