Real-world EGFR testing practices for non-small-cell lung cancer by thoracic pathology laboratories across Europe.

BACKGROUND: Testing for epidermal growth factor receptor (EGFR) mutations is an essential recommendation in guidelines for metastatic non-squamous non-small-cell lung cancer, and is considered mandatory in European countries. However, in practice, challenges are often faced when carrying out routine biomarker testing, including access to testing, inadequate tissue samples and long turnaround times (TATs). MATERIALS AND METHODS: To evaluate the real-world EGFR testing practices of European pathology laboratories, an online survey was set up and validated by the Pulmonary Pathology Working Group of the European Society of Pathology and distributed to 64 expert testing laboratories. The retrospective survey focussed on laboratory organisation and daily EGFR testing practice of pathologists and molecular biologists between 2018 and 2021. RESULTS: TATs varied greatly both between and within countries. These discrepancies may be partly due to reflex testing practices, as 20.8% of laboratories carried out EGFR testing only at the request of the clinician. Many laboratories across Europe still favour single-test sequencing as a primary method of EGFR mutation identification; 32.7% indicated that they only used targeted techniques and 45.1% used single-gene testing followed by next-generation sequencing (NGS), depending on the case. Reported testing rates were consistent over time with no significant decrease in the number of EGFR tests carried out in 2020, despite the increased pressure faced by testing facilities during the COVID-19 pandemic. ISO 15189 accreditation was reported by 42.0% of molecular biology laboratories for single-test sequencing, and by 42.3% for NGS. 92.5% of laboratories indicated they regularly participate in an external quality assessment scheme. CONCLUSIONS: These results highlight the strong heterogeneity of EGFR testing that still occurs within thoracic pathology and molecular biology laboratories across Europe. Even among expert testing facilities there is variability in testing capabilities, TAT, reflex testing practice and laboratory accreditation, stressing the need to harmonise reimbursement technologies and decision-making algorithms in Europe.

Serum tumor marker CYFRA 21-1 in the diagnostics of NSCLC lung cancer.

Cytokeratins are epithelial markers whose expression is not lost during malignant transformation. The level of soluble cytokeratin fragment 19 was measured with an enzyme immunoassay method developed by Boehringer Mannheim (Enzymum-test CYFRA 21-1) in the serum of 200 male and 50 female patients with NSCLC (Non Small Cell Lung Cancer) lung cancer (120 planocellulare and 80 adenocarcinoma in males; 22 planocellulare and 28 adenocarcinoma in females). The comparative group comprised 50 young healthy males and 50 females without any clinical proof for malignancy or any other lung disease. The aim of this investigation was to find out if any possible statistical difference exists in the serum level of CYFRA 21-1 between patients with lung cancer and healthy controls, and also between different types of lung cancers. The mean value of serum CYFRA 21-1 in NSCLC (6.25 ng/ml) was significantly higher than in healthy controls (1.26 ng/ml) (p < 0.001). Sensitivity for CYFRA 21-1 (using 3.3 ng/ml, a cut-off value corresponding to a 98% specificity for healthy controls) in NSCLC was 60.5%. Positive CYFRA 21-1 levels were significantly higher in patient with carcinoma planocellulare (66.2%) than in adenocarcinoma (52.1%). CYFRA 21-1 levels were significantly different between squamous cell carcinoma (6.52 ng/ml) and adenocarcinoma (5.86 ng/ml) (p < 0.05). Our results indicate that CYFRA 21-1 may be a useful tumor marker in NSCLC, especially in carcinoma planocellulare. CYFRA 21-1 may also be useful in identification of the preoperative stages of diseases and the postoperative monitoring of NSCLC.