Breast Cancer Molecular Subtypes and Receptor-Related Risk Factor Associations: A Cross-Sectional Study

Area of Science:

• Oncology
• Molecular Biology
• Epidemiology

Background:

• Breast cancer is a leading global cancer in women.
• Understanding molecular subtypes is crucial for effective treatment strategies.
• This study focuses on the Qazvin region of Iran.

Purpose of the Study:

• To determine the frequency of breast cancer molecular subtypes.
• To investigate associations between Estrogen Receptor (ER), Progesterone Receptor (PR), and HER2 status with demographic, reproductive, hormonal, and cancer stage.
• To provide insights into breast cancer characteristics in the Iranian population.

Main Methods:

• Cross-sectional study of 333 women with primary breast cancer.
• Data collected via medical records and interviews.
• Immunohistochemistry used for ER, PR, HER2, and Ki67 assessment; statistical analyses included chi-squared, t-tests, and multinomial logistic regression.

Main Results:

• Luminal A was the predominant subtype (47%).
• ER, PR, and HER2 positivity rates were 68.5%, 62.5%, and 32.7%, respectively.
• ER- and PR- tumors were more frequently diagnosed at advanced stages (III). HER2+ tumors were associated with higher stage at diagnosis and absence of family history.

Conclusions:

• Luminal A is the most common breast cancer subtype in this cohort.
• Hormone receptor and HER2 status correlate with advanced tumor stage.
• Molecular profiling is essential for understanding breast cancer in this population and guiding treatment.