Endocrine Abstracts

Introduction: Differenziated thyroid carcinomas (DTC), particularly papillary thyroid carcinomas (PTCs), usually have an indolent behavior, howewer 10-20% of the patients develop recurrences, following surgery. There are several histological features associated with more frequent recurrences as the hystopathological variants of PTCs, the presence of vascular invasion or lymph node metastases and the presence of extrathyroidal extension (ETE). Case history: a 56yrs old male patient prevously treated for PTC, with excellent response to the first treatment, presented twelve years after a gradual increase of thyroglobulin (Tg) (from 0.3 to 0.76 ng/ml in 6 months) and a neck lump in the left cervical region at ultrasound imaging. Fine needle aspiration cytology of the mass and Tg measurement in the wash out liquid of the needle was 472 mg/l. Cytology revealed polymorphous epithelial cells with atypical nuclei suggesting metastasis of PTC. Surgery was then performed and pathology showed a massive metastasis in the local adipose tissue and striated muscles of the neck. Genetic analysis of the primary tumor and metastatic tissue revelead a BRAF p. V600E in both primary tumor and in metastatic tissue (37% and 48% respectively). Conclusions: Our patient’s history suggests the need of a continuous and prolonged follow-up in patients with multiple features that increase the recurrence risk (minimal ETE, size >2 cm, BRAF V600E mutation as in our case).

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