Lung cancer biopsy: Can diagnosis be changed after immunohistochemistry when the H&E-Based morphology corresponds to a specific tumor subtype?

Abstract

OBJECTIVES:Advancements in non-small cell lung cancer treatment based on targeted therapies have made the differentiation between adenocarcinoma and squamous cell carcinoma increasingly important. Pathologists are challenged to make the correct diagnosis in small specimens. We studied the accuracy of an immunohistochemical panel in subclassifying non-small cell lung cancer in routine small biopsies and compared the results with the diagnosis from resected lung specimens, autopsy samples or biopsied/resected metastases.METHODS:In total, 340 lung cancer biopsies were investigated for the expression of CK5, TTF1, p63 and surfactant.RESULTS:We characterized 166 adenocarcinomas and 124 squamous cell carcinomas. Overall, 85% of cases displayed binary staining (TTF1 positive/p63 negative, and vice versa). The diagnoses of ten cases with a morphology that indicated a specific tumor subtype were changed after immunohistochemistry (IHC). A second specimen was available for 71 patients, and the first diagnosis at biopsy was confirmed in 95% of these cases. Most non-small cell lung cancer cases present a binary immunohistochemical profile in small biopsies, contributing to good diagnostic accuracy with routine markers. In a small proportion of cases, the diagnosis can be changed after IHC even when the morphological aspects indicate one specific tumor subtype.CONCLUSIONS:We recommend that routine small biopsies of lung cancer without classic morphology should be subjected to a minimum immunohistochemical panel to differentiate adenocarcinoma from squamous cell carcinoma.

Use of dual-marker staining to differentiate between lung squamous cell carcinoma and adenocarcinoma

“…Although well-differentiated SqCC can be easily distinguished from well-differentiated ADC, the classification of poorly differentiated cancers based on H&E sections is challenging. 21 IHC is routinely used to classify various types of cancers, with approximately one-third of NSCLC cases requiring IHC for accurate differentiation. 22 – 24 The 2015 World Health Organization Classification Guidelines recommend the use of IHC with at least one SCC marker and one ADC marker.…”

Cell Membrane Coated pH-Responsive Intelligent Bionic Delivery Nanoplatform for Active Targeting in Photothermal Therapy

“…Firstly, the changes in body weight showed no statistically significant difference among the ICG-PEI@HM+Laser, Control, and ICG-PEI@HM groups ( Figure 8E ) suggesting no effect on mice growth. Furthermore, compared with the Normal group (without tumor), pathological analysis (H&E staining) showed no pathological enlargement in the alveolar cavity or congestion in the alveolar interstitial vessels 28 in the ICG-PEI@HM+Laser group. Also, no significant damages were noticed in other major organs including the heart, liver, spleen, and kidney ( Supplementary Figure 9 ).…”