Natural history and clinical features of metastatic differentiated thyroid carcinoma
Marta Dieguez, Edelmiro Menendez, Cecilia Sanchez, Javier Aller, Elias Delgado, Pedro Boix, Antonio Lavilla, Joaquin Pertierra & Antonio Rabal
Aim: To analyze clinical features in a group of 65 patients with differentiated thyroid carcinoma and distant metastases.
Methods: Retrospective review of 65 patients with Metastatic Differentiated Thyroid Carcinoma (MDTC) identified from the database of a tertiary hospital between 1975 and 2008.
Results: Sixty five patients were identified (21 males, 44 females) with a mean age of 58,9 years. The median follow-up after discovery of the metastases was 90 months (range 3328) Histologically, there were 18 (28%) Papillary Carcinoma (PC), 33 (51%) Follicular Carcinoma (FC) and 14 (21%) Hürthle Carcinoma (HC).
Metastasis were initially present in 49% of patients and were diagnosed later in 51% (15.3% <1 years, 15.3% 15 years, 8.2% 510 yr and 12.2% >10 years after thyroidectomy).
We observed lung metastases (LM) in 63% of patients, bone metastases (BM) in 32% and other metastases in 5% of patients. Only 3 patients presented with multisystemic metastases extension.
LM represented 83% of metastases in PC and 79% in CH. Among FC 52% were LM and 48% BM. Most LM (93%), but only 50% of BM were multiple. 34% of metastases were non-iodine-avid.
Conclusions: Our series is characterized by the high rate of FC and HC which could be explained by the historical regional iodine deficiency.
Distant metastases are often observed at initial presentation of DTC but later diagnosis in the follow-up is about as common.
Iodine-avid lung metastases are the commonest between all histological subtypes with a high rate of BM in FC patients.