Unstimulated Serum Thyroglobulin Levels after Thyroidectomy and Radioiodine Therapy for Intermediate-Risk Thyroid Cancer Are Not Always a Reliable Marker of Lymph Node Recurrence: Case Report and a Lesson for Clinicians

Figure 5

Histology of lymph node metastasis (first recurrence detected during the fourth year of follow-up after surgery and radioactive 131I therapy) of tall-cell variant of papillary thyroid carcinoma: proliferation of cells with a large eosinophilic cytoplasm, “ground glass” nuclei, and evident nuclear grooves and pseudoinclusions (left side) and residual patrimonial lymphoid tissue (right side) (haematoxylin-eosin stain, 40X, (a)). The neoplastic thyroid cells showed scattered thyroglobulin cytoplasmatic staining of different intensity (40X, (b)) and diffuse strong cytoplasmatic CK19 staining (40X, (c)). Immunohistochemical staining was performed using specific antibodies by indirect biotin streptavidin 3, 3′-diaminobenzidine (DAB) system.

(a)

(b)

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