Clear cell lesions of the head and neck: The spectrum of histological features

Abstract

Objective: Estrogen receptor (ER) positive breast cancer (BC) can havean insidious course with disease-relapse decades after primary surgery.New analysis performed on archived formalin-fixed paraffin-embedded(FFPE) tissue are important for disease-management in late BC-relapseand an important tool in BC-research. However, although loss of immunoreactivityin tissue slides after sectioning has been shown, little isknown of the preservation of biomarker-expression in FFPE tumourblocks.We aim to investigate the quality of immunohistochemical(IHC) ER-evaluation in FFPE-tissue over time (1978–2000).Method: Tissue-microarrays from a Swedish multicenter cohort of 728patients with contralateral BC was used for ER IHC-evaluation. BC wasstudied in three periods (1958–1985, 1986–1993, 1994–2000), and retrospectiveER IHC-data was correlated to corresponding prospective ERcytosol-analysis performed on fresh BC-tissue.Results: The concordance between the original ER cytosol-analysis andthe new IHC was substantial (1978–1985: 82 %, (117/142), Kappa 0.52.1986–1993: 91 %, (194/213), Kappa 0.72. 1994–2000: 86 %, (187/218),Kappa 0.61). Discrepancies were mostly found for tumours with ERvaluesclose to cutoff for one or both of the methods.Conclusion: FFPE BC-tissue from the late 70s to millennium showspreserved ER-antigenicity up to 35 years later