Napsin A (aspartic protease) immunostain in respiratory cytology is a cytoplasmic marker for lung adenocarcinoma, showing granular cytoplasmic staining. It is used to: 1) Confirm pulmonary origin of adenocarcinoma (positive in 80-90% of lung adenocarcinomas), 2) Distinguish lung adenocarcinoma from squamous cell carcinoma (negative) and mesothelioma (negative), 3) Support diagnosis of adenocarcinoma when TTF-1 is negative or equivocal, and 4) Identify primary lung adenocarcinoma versus metastasis (most extrapulmonary adenocarcinomas are napsin A negative, except some renal and thyroid). Napsin A is often used with TTF-1 for increased sensitivity and specificity. It is performed on cell blocks or liquid-based preparations.

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Zambia

• Joseph Soko – 101 pts

• Visual Pathway Lesions
• Positive and Negative Symptoms
• Hallucinations and Delusions
• Antipsychotic Medications
• Emergency: Environmental Emergencies