p40 (ΔNp63) immunostain in respiratory cytology is a specific marker for squamous differentiation, showing nuclear staining. It is used to: 1) Distinguish squamous cell carcinoma (positive) from adenocarcinoma (negative), 2) Confirm squamous differentiation in poorly differentiated tumors, 3) Identify squamous metaplasia, and 4) Differentiate squamous cell carcinoma from other neoplasms (e.g., small cell carcinoma, lymphoma). p40 is more specific than p63 for squamous lineage. It is often used in combination with TTF-1 (for adenocarcinoma) and neuroendocrine markers. The stain is performed on cell blocks or liquid-based cytology and is crucial for accurate classification of non-small cell lung carcinoma.

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Zambia

• Joseph Soko – 101 pts

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