Clinicopathological features of cytokeratin 5‐positive pulmonary adenocarcinoma

• Published in: Histopathology 2023-02, Vol.82 (3), p.439-453
• Main Authors: Terada, K, Yoshizawa, A, Sumiyoshi, S, Rokutan‐Kurata, M, Nakajima, N, Hamaji, M, Sonobe, M, Menju, T, Date, H, Haga, H
• Format: Article
• Language: English
• Subjects: Adenocarcinoma; Adenocarcinoma - genetics; Adenocarcinoma of Lung; Biomarkers, Tumor - analysis; Cancer; Cytokeratin; cytokeratin 5; Female; high‐grade components; Humans; Immunohistochemistry; Keratin-5 - analysis; Lung carcinoma; Lung Neoplasms - pathology; Male; mucinous differentiation; Multivariate analysis; Physical characteristics; Prognosis; Protein-Tyrosine Kinases; Proto-Oncogene Proteins; pulmonary adenocarcinoma; Squamous cell carcinoma; Tumors
• ISSN: 0309-0167; 1365-2559
• DOI: 10.1111/his.14827

Cytokeratin 5 (CK5) is a marker for pulmonary squamous cell carcinoma; however, CK5 is sometimes present in pulmonary adenocarcinoma (ADC), and there is insufficient information regarding the clinicopathological features of CK5‐positive ADC. We aimed to explore the clinicopathological characteristics of CK5‐positive ADC using immunohistochemistry. We prepared the following two cohorts: a resected cohort containing 220 resected tumours for primarily studying the detailed morphological characteristics, and a tissue microarray (TMA) cohort containing 337 samples for investigating the associations of CK5 expression with other protein expressions, genetic and prognostic findings. CK5‐positive ADC was defined to have ≥ 10% tumour cells and presence of CK5‐positive tumour cells in the resected and TMA cohorts, respectively. CK5‐positive ADCs were identified in 91 (16.3%) patients in the combined cohort. CK5‐positive ADCs had male predominance (P = 0.012), smoking history (P = 0.001), higher stage (P