What are Hobnail cells ?

Hobnailing is seen in

1. Clear cell ovarian adenocarcinoma,
2. Papillary thyroid carcinoma
3. Collecting duct carcinoma
4. End-stage cirrhosis

Papillary thyroid carcinoma

• Characterized by predominance of cells with a hobnail appearance often arranged in micropapillary pattern
• Aggressive variant

Clear cell ovarian adenocarcinoma

• Mesonephroid primary ovarian adenocarcinoma – clear cell

• Clear cell (mesonephroid) tumors contain cells with abundant glycogen
• Most common cell types in clear cell carcinomas of the ovary are clear cells and hobnail cells

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Hobnail cells

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