Molecular Epidemiology of Breast Cancer in Iran: A Review Article

Breast cancer (BC) was the most common cancer in Iran, accounting for 12.9% of all incident cancer, and was the 5th leading cause of cancer death in 2020. The latest age standardized incidence rate (ASIR) of breast cancer was 35.8 in Iran and is expected to increase to more than 70 per 100,000 by the end of 2030. Incidence of breast cancer had a clustering pattern in Iran, while central provinces had the highest ASIR (72 per 100,000 population), and South East provinces had the lowest ASIR (5-11 per 100,000 population). Numerous studies have shown that the peak incidence of breast cancer was occurred in the age group of 40-49 years in Iran. There has also been reported a rapid increase in the incidence in young women from different regions of the country. Known molecular and cellular processes involved in the development of breast cancer in Iranian BCs have been reported from various studies in recent decades, and the most well-known and prominent genes susceptible to breast cancer were BRCA1 and BRCA2.  They acted as tumor suppressor genes and inherited mutations leading to chromosomal instability. However, non-coding RNAs, epigenetic alterations, signaling pathways, immune responses, and antioxidant-related genes are the main molecular processes associated with the progression of breast cancer among Iranian patients. While we are facing a significant increase in the incidence of breast cancer, with a lower survival rate, breast cancer is currently considered as one of the major health problems in Iran, which emphasizes the importance of providing and designing prevention and early detection program of breast cancer.