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