Akciğer Kanserinde ERCC1 Protein Varlığının PET-BT'de 18F-FDG Tutulumu ile Olan İlişkisi ve Prognostik Önemi

Abstract

Lung cancer is the most frequently diagnosed cancer and the leading cause of death from malignancy. It causes worldwide mortality of about 1.3 million people annually. Approximately 85% of lung cancer is non small cell lung cancer (NSCLC). With early diagnosis effective treatment can be provided. Surgery is the most effective treatment modality. Surgery, chemotherapy, radiotherapy and combined therapies may be preferred to stage. Smoking is shown as the main cause of it. PETCT (Positron Emission Tomography-Computed Tomography) in diagnosis and staging of NSCLC is an important non-invasive method. Chemotherapy resistance is a clinical treat for NSCLC, EGFR (Epidermal Growth Factor Receptor), p53 and ERCC1 (Excision Repair Cross-Complementing Group-1 ) is just as important biomarkers have been shown to correlate well with. ERCC1 is one of the key enzymes in the nucleotide excision repair pathway. ERCC1 is involved in the removal of Platinum-DNA (Deoxyribonucleic Acid) waste. High ERCC1 expression in NSCLC is an important prognostic factor, but at the same time is a predictive parameter of showing drug resistance to chemotherapy. There is limited number of studies showing the relationship between PET-CT and chemotherapy resistance tumor markers are available. In this study, the relationship between the expression of ERCC1 and the 18F-FDG uptake in the tumor (SUVmax value- Maximum Standart Uptake Value) in PET-CT for staging was examined and was aimed to evaluate as the prognostic factor. In our clinic, between 2008 and 2013, 71 patients with lung cancer, with complete resection due to lung cancer were included in the study. Patient data were obtained retrospectively from Hacettepe University Hospitals archive files and from the automation system, pathological specimens including paraffin blocks of patients after resection were obtained from Hacettepe University Faculty of Medicine Department of Pathology archives. The slides prepared from paraffin blocks of patients were stained immunohistochemically with ERCC1 antibody. Nuclear staining was considered positive, then slides were evaluated with the semiquantitative scoring made out of staining intensity and extent of the preparations. Statistically significant relationship (P <0.05) between SUVmax and tumor size, stage, to take or not adjuvant chemotherapy, survival and longer than 1 year of follow-up was found. The difference between average SUVmax value of Stage IA and IIB was statistically significant (P = 0.020). Consistent with the literature, ERCC1 (+) and survival rates in the same direction was found to be a statistically significant relationship (P = 0.016). In NSCLC, ERCC1 been found to be an independent prognostic factor although the relationship with SUVmax could not be shown as a single value. From the patients whose SUVmax value of 2.5 and / or higher, 57.4% of those who alive are ERCC1 (+), while 29.4% of those who died are ERCC1 (+) was detected. The difference was statistically significant (P = 0.048). Clear and common results can be obtained with quantitative scoring systems created for ERCC1 in future studies.