Utility of Immunohistochemistry in the Diagnosis of Pleuropulmonary and Mediastinal Cancers: A Review and Update

Abstract

Context.-Immunohistochemistry has become an indispensable ancillary tool for the accurate classification of pleuropulmonary and mediastinal neoplasms necessary for therapeutic decisions and predicting prognostic outcome in the era of personalized medicine. Diagnostic accuracy has significantly improved because of the continuous discoveries of tumor-associated biomarkers and the development of effective immunohistochemical panels.Objective.-To increase the accuracy of diagnosis and classify pleuropulmonary neoplasms through immunohistochemistry.Data Sources.-Literature review, authors' research data, and personal practice experience.Conclusions.-This review article has shown that appropriately selecting immunohistochemical panels enables pathologists to effectively diagnose most primary pleuropulmonary neoplasms and differentiate primary lung tumors from a variety of metastatic tumors to the lung. The discovery of new mutation-specific antibodies identifying a subset of specific gene-arranged lung tumors provides a promising alternative and cost-effective approach to molecular testing. Knowing the utilities and pitfalls of each tumor-associated biomarker is essential to avoiding potential diagnostic errors.

Primary lung sarcoma treated with stereotactic ablative radiotherapy: a case report

“…Immunohistochemical staining was positive for desmin and smooth muscle actin, and negative for ALK, Pan-CK, CAM5.2, HMB45, Melan-A, P40, and TTF-1. The pathology and immunohistochemistry findings were consistent with leiomyosarcoma 10. Whole-body 18 F-fluorodeoxyglucose positron emission tomography-CT did not detect any pathologically increased uptake, except above the mass, with a maximum standardized uptake value of 2.24.…”

Ribonucleic Acid In Situ Hybridization Is a More Sensitive Method Than Immunohistochemistry in Detection of Thyroid Transcription Factor 1 and Napsin A Expression in Lung Adenocarcinomas

“…[11][12][13] In contrast, p40 and cytokeratin (CK) 5/6 is a small panel of specific markers to render a diagnosis of SCC. 19 The reported diagnostic sensitivity for TTF-1 and napsin A varies in the literature but was approximately 75% to 80% for TTF-1 and 75% for napsin A. [11][12][13] The diagnostic sensitivity of these 2 markers is similar for both primary and metastatic lung ACAs in our unpublished data and experience.…”

A practical guide for ancillary studies in pulmonary cytologic specimens

“…Combinations of immunocytochemical markers, typically combining a nuclear staining antibody with a cytoplasmic staining antibody (eg, TTF1 and napsin A; P40 and CK5/6) can also be used to save material for molecular studies. 8,[11][12][13][14][15] Finally, some institutions can also opt to perform ancillary studies on all NSCLC, even when well-differentiated; however, such an approach is not desirable nor necessary in cost-conscious settings. 5 Of note, the phrasing of the diagnosis in the cytology report (as is for histologic reports) depends on the use (or not) of ancillary studies ( Fig.…”