p40 (ΔNp63): A Highly Sensitive and Specific Immunohistochemical (IHC) Marker for Diagnosing Pulmonary Squamous Cell Carcinomas (SQCC) in Fine Needle Aspirates
Adam P Vogt, Cynthia Cohen, Momin T Siddiqui. Emory University School of Medicine, Atlanta, GA
Background: The treatment of pulmonary non-small cell carcinoma has become sharply divided between the therapeutic options now devoted to squamous cell carcinoma (SQCC) and those of adenocarcinoma (ADC). Due to the increasing ability to make a diagnosis on minimal tissue, ancillary techniques such as immunohistochemistry (IHC) are needed and must be highly sensitive and specific. The popular squamous cell IHC marker p63 has demonstrated cross-reactivity with a subset of pulmonary adenocarcinomas and lymphomas, causing it to be less specific than originally thought. The IHC marker p40 (ΔNp63) is a truncated isoform of p63 that is a promising IHC marker for SQCC. In this study we have studied and compared its utility with p63 and cytokeratin 5 on fine needle aspiration (FNA) cell blocks (CB).
Design: Thirty cases of pulmonary SQCC and thirty cases of pulmonary ADC with CB were selected. IHC for p40 (ΔNp63), p63, and cytokeratin 5 were performed on all paraffin-embedded CB serial sections.
|Squamous cell carcinoma||Adenocarcinoma|
|Marker||Positive||Negative||Percent Positive||Marker||Positive||Negative||Percent Positive|