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What is A 67 yr male with history of chronic smoking hemoptysis with cough. Bronchoscopic biopsy from centrally located mass shows undifferentiated tumor histopathologically. Most useful I.H.C. (immunohistochemical) marker to make a proper diagnosis would be and explain in detail?
• The presence of chronic smoking, cough and hemoptysis in old man is a pointer towards a diagnosis of bronchogenic cancer. The central location suggests the possibility of a squamous cell cancer.
• Robbins writes “Histologically, this tumor is characterized by the presence of keratinization and/or intercellular bridges”.
Other options: HMB (melanoma), Hep par1 (liver cancer) and parvalbumin (schizophrenia).