Cisto hepático benigno simulando metástase de carcinoma diferenciado de tireoide

Abstract

ResumoIntrodução: Pesquisa de corpo inteiro após dose terapêutica de (¹³¹I) NaI (PCI) associada à tireoglobulina (Tg) sérica, anticorpo antitireoglobulina (anti-Tg) e ultrassom (US) cervical representam os métodos de referência para detecção de carcinoma diferenciado de tireoide (CDT) residual ou metastático. Algumas causas de PCI falsos-positivas, como processos inflamatórios, alguns tumores não tireoidianos e até mesmo cistos renais e sebáceos, são bem conhecidas. Métodos: Neste trabalho, descreveu-se um caso de cisto hepático benigno simulando metásta-se de carcinoma de tireoide em PCI após dose terapêutica de (¹³¹I) NaI. Resultados: Ressalta-se a importância do reconhecimento dos cistos hepáticos benignos como fator complicador do seguimento dos pacientes com câncer de tireoide. Conclusões: Para minimizar erros de diagnós-tico e, consequentemente, na condução dos casos de CDT, é necessário conhecer as possíveis causas de PCI falsos-negativas e positivas. Arq Bras Endocrinol Metab. 2009;53(6):777-82 Descritores Cisto hepático; pesquisa de corpo inteiro após (¹³¹I) NaI; carcinoma tireoidiano AbstRAct Introduction: The follow-up of differentiated thyroid carcinoma (DTC) for detecting persistent or recurrent disease is based on iodine whole body scan (WBS), the evaluation of the tumor marker thyroglobulin (Tg), the anti-thyroglobulin antibody (anti-Tg) and neck ultrasonography (US). Well known false-positive causes of WBS include inflammatory processes, some non-thyroid tumors, kidney or even sebaceous cysts . Methods: We reported a case of falsepositive WBS, after therapeutic dose of ( 131 I) NaI. Results: We enphasize the importance of recognizing benign liver cysts mimicking DTC metastasis. Conclusions: False-positive and negative results may occur with WBS and must be recognized to avoid mismanagement. Arq

Incidentally polycystic kidney disease identified by SPECT/CT with post-therapy radioiodine scintigraphy in a patient with differentiated thyroid carcinoma

“…Although the exact mechanism of this phenomenon is unclear, it may be similar to that of renal cysts. [ 10 ] One possible reason is that there is a communication between the renal cyst and the collecting systems of kidney. [ 11 – 13 ] Another is due to NIS, which promotes iodine transport in the thyroid, has recently been found in renal tissue.…”

“…It is true that the diagnosis of PKD is mainly made by CT or ultrasound and the renal cysts sometimes accumulate I-131. However, the literature was published in 1988, [ 10 ] when there was no SPECT/CT in the world, which led to the fact that the association between the accumulation of I-131 and the renal cyst was not precise and immediate. In this paper, the relationship of PKD and the accumulation of I-131 could be established definitely on the images of SPECT/CT.…”