Endocrine Abstracts

Introduction: Papillary thyroid carcinoma (PTC) distant metastases without regional lymph node metastases are quite rare. Spinal cord teratomas are rare tumors mostly seen in children. To the best of our knowledge, the development of papillary carcinoma in intradural teratomas is theoretically possible, but has not been reported in literature.

Case report: A 36-year-old female patient admitted with the complaint of drop foot. On MRI, 20x11x20.5 mm lesion was observed at the T5 level and caused significant compression on the spinal cord. Surgical excision was performed due to drop foot. During surgery, a mass was detected on both sides of the spinal cord, the same color as the neural tissue and adherent to the cord, with a firmer consistency. Histopathological and immunohistochemical findings primarily suggested PTC metastasis. However, the presence of adipose tissue observed in the glial tissue neighborhood and the different degrees of immunoreactivity of the described glandular structures in different areas also consistent with a PTC on the basis of teratoma. With S100, glial tissue and adipocytes were positive. PAX8 and CK19 were positive in large areas. TTFI, HBME1, Galectin3, Gata3, ER, PR and EMA were positive in varying degrees and localizations. Thyroglobulin was positive in the secretions of the gland lumens. CEA, GCDP 15 and NapsinA were focal positive. In the thyroid gland no lesion or pathological FDG uptake could be detected via PET-CT. No pathological FDG uptake was observed in the neck. Also, 17x11 mm sized lesion at the lateral of the left ovary and anterior of psoas muscle had 3.5 SUVmax was reported. However this lesion was not seen in MRI evaluation. AntiTPO and antiTg were positive. In the thyroid ultrasonography, the parenchyma was heterogeneous and contained pseudonodular areas. A 4x4x6 mm well-circumscribed isoechoic solid nodule and a 6x7x8 mm isoechoic mixed solid nodule with cystic areas was observed in the left lobe. Thyroid FNAB performed from the index nodüle. The result was reported as atypia of undetermined significance. Total thyroidectomy followed by RAI ablation was planned as the treatment protocol to facilitate long-term follow up.

Conclusion: Clarification of the diagnosis of the neoplasms is imperative. Because treatment and follow-up protocols are shaped according to diagnosis. However, in some cases, the etiologic diagnosis of a neoplasm can be a real challenge for clinicians. As in our case, in unusual localized neoplasms, follow-up and treatment should be arranged by using additional diagnostic methods.