Molecular and immunohistochemical biomarkers in colorectal carcinoma - a single center study

Objective: Colorectal cancer is the third most common malignancy in the world and among the most frequent causes of cancer-related death. Our study aimed to
evaluate the molecular profile of the patients diagnosed
with colorectal carcinoma at Clinical Hospital AcibademSistina in Skopje.
Materials and methods: This study is retrospectiveprospective, conducted at the Department of histopathology and cytology, at Clinical Hospital Acibadem-Sistina in Skopje. Tissue samples from surgical material from 152patients diagnosed with CRC were processed for molecular and immunohistochemical analysis. KRAS and BRAF
mutations were analyzed, and MMR status was obtained.
In 90 metastatic cases, evaluation of HER2 and PDL-1
expression was performed on a tissue microarray.
Results: Among 152 analyzed patients diagnosed
with colorectal carcinoma, the majority were males (98,
64.47%) compared to females (54, 35.53%). The mean
age was 68.4±11.3 years; the median age was 70 years.
KRAS/NRAS mutations were detected in 47(31%) of patients, BRAF mutations in 11(7%) patients, and mismatch
repair gene deficiency (MMRd) was found in 15(10%) of
patients. HER2 positive expression was present in 36(40%)
of patients, and 17(19%) of patients showed PDL-1 expression. In the group of 17 PDL1-positive tumors, a cutoff of more than 1% positive tumor cells was detected in 10 cases, more than 10% tumor cells in 4 cases, and more than 50% tumor cells in 3 cases. From 36 HER2 positive cases,32(32,5%) were with score 2+, and 4(4,4%) with score 3+.Conclusions: Continued research into molecular
mechanisms and biomarkers holds the promise of further
improving CRC outcomes through personalized and effective interventions.