case_images: PMC3307468_01
case_images: (a) Cytological smears from thyroid show neoplastic epithelial cells (yellow arrow) scattered along with thyroid epithelial clusters (red arrow) (Giemsa, x200). (b) Smears reveal neoplastic epithelial cells with signet ring morphology containing intracellular mucin (Giemsa, x200); inset (Giemsa, x400). (c) Biopsy from lung mass showing neoplastic cells with signet ring morphology (H and E, x200). (d) Tumor cells expressing strong nuclear positivity for Thyroid transcription factor -1 (DAB, x200)
case_images: JCytol-29-92-g001.jpg
case_images: PMC3307468_01_JCytol-29-92-g001.jpg
case_images: F1
case_images: The patient underwent an ultrasonogram-guided fine needle aspiration cytology (FNAC) subsequently, which showed a cellular aspirate comprising predominantly of cohesive clusters of atypical epithelial cells having hyperchromatic eccentric nucleus and moderate to abundant amount of vacuolated cytoplasm with occasional scattered thyroid follicular epithelial cell clusters with absence of colloid [Figure 1a]. Intracellular mucin was readily evident imparting signet ring cell appearance [Figure 1b]. Bronchoscopic-guided biopsy was done, which revealed histopathological features of mucinous adenocarcinoma [Figure 1c]. On immunohistochemistry (IHC), the tumor cells showed immunoreactivity for cytokeratin 7 and thyroid transcription factor-1, [Figure 1d] whereas it was negative for thyroglobulin.