CT CT Fine Needle Aspiration Cytology 2 — Questions and Answers
Question 1: FNA of a salivary gland mass yields clusters of cells with abundant granular cytoplasm, well-defined cell borders, round nuclei with prominent nucleoli, and background mucoid stroma. What is the most likely diagnosis?
- Warthin tumor
- Pleomorphic adenoma (Correct answer)
- Mucoepidermoid carcinoma
- Adenoid cystic carcinoma
Correct answer: Pleomorphic adenoma
Pleomorphic adenoma (mixed tumor) is characterized by epithelial cells embedded in magenta-colored chondromyxoid stroma, a combination pathognomonic for this diagnosis.
Question 2: On FNA of a lymph node, the finding of a monotonous population of small lymphoid cells with scant cytoplasm, round nuclei, and clumped chromatin is most suspicious for which condition?
- Reactive hyperplasia
- Small lymphocytic lymphoma/CLL (Correct answer)
- Hodgkin lymphoma
- Metastatic carcinoma
Correct answer: Small lymphocytic lymphoma/CLL
A monomorphic small lymphocyte population without the mixed spectrum of reactive lymph nodes suggests small lymphocytic lymphoma or CLL, requiring flow cytometry confirmation.
Question 3: Which cytomorphologic feature in a pancreatic FNA best distinguishes adenocarcinoma from chronic pancreatitis?
- Mucin production
- Drunken honeycomb pattern with nuclear enlargement, irregular spacing, and anisonucleosis (Correct answer)
- Inflammatory background
- Acinar cell clusters
Correct answer: Drunken honeycomb pattern with nuclear enlargement, irregular spacing, and anisonucleosis
Pancreatic adenocarcinoma shows a 'drunken honeycomb' pattern with irregular nuclear spacing, size variation, and membrane irregularity, contrasting with the orderly arrangement of benign ductal cells.
Question 4: FNA of a lung mass in a 65-year-old smoker shows single cells with abundant dense cytoplasm, intercellular bridges, and keratinization. What is the most likely cytologic diagnosis?
- Adenocarcinoma
- Small cell carcinoma
- Squamous cell carcinoma (Correct answer)
- Large cell carcinoma
Correct answer: Squamous cell carcinoma
Squamous cell carcinoma of the lung shows keratinization, intercellular bridges, dense orangeophilic cytoplasm, and single malignant squamous cells with irregular hyperchromatic nuclei.
Question 5: Which characteristic feature distinguishes small cell carcinoma of the lung from lymphoma on FNA cytology?
- Small cell size
- Nuclear molding and crush artifact with Azzopardi effect (DNA encrustation) (Correct answer)
- Single dispersed cells
- High N:C ratio
Correct answer: Nuclear molding and crush artifact with Azzopardi effect (DNA encrustation)
Small cell carcinoma shows nuclear molding (cells conforming to each other's shapes), crush artifact, and the Azzopardi effect (DNA streaking along vessel walls), features absent in lymphoma.
Question 6: Which ancillary test is the most important to order following FNA of a mediastinal mass yielding large atypical lymphoid cells to ensure proper classification?
- Mucicarmine special stain
- Flow cytometry immunophenotyping (Correct answer)
- Oil red O stain
- Periodic acid-Schiff (PAS) stain
Correct answer: Flow cytometry immunophenotyping
Flow cytometry allows definitive immunophenotyping of lymphoma subtypes, which is essential for treatment planning and cannot be accomplished on morphology alone.
CT CT Fine Needle Aspiration Cytology 2
FNA of a salivary gland mass yields clusters of cells with abundant granular cytoplasm, well-defined cell borders, round nuclei with prominent nucleoli, and background mucoid stroma.
What is the most likely diagnosis?