Fig. 2

Cytological and histological illustrations of case 2. a Cytological preparation from the thyroid lesion at × 600 magnification depicting thyrocytes with large, irregular nuclei with suggestive nuclear marginalization in subsets of cells. The vast majority of cells were without this phenomenon, and no evident signet-ring cell phenotype was observed. b H&E staining of the thyroid tumor at × 400 magnification, showing thyrocytes with signet ring cell morphology in subsets (30–50%) of tumor cells. c Central parts of the lesion displayed a dense fibrous meshwork with focal hemorrhages and only sparsely found tumor cells. d One of several areas with capsular invasion, × 100 magnification. e-g Immunohistochemical analyses at × 400 magnification; Cytokeratin MNF116 cytoplasmic stain (e), thyroglobulin cytoplasmic stain, including subsets of vacuoles (f) and PTEN nuclear and cytoplasmic staining (g). h: Chromatogram displaying the c.209 + 11 T > G PTEN mutation in leukocyte DNA. The red line represents the wildtype thymine (T) and the black line represent the mutant guanine (g) at position c. 209 + 11