HER2n

HER2n is a term used in the field of oncology to describe a specific subtype of breast cancer. HER2n refers to breast cancers that are HER2-negative and have a high level of expression of the human epidermal growth factor receptor 2 (HER2) protein. This subtype is distinct from HER2-positive breast cancer, which is characterized by an amplification or overexpression of the HER2 gene.

HER2n breast cancer is a rare subtype, accounting for approximately 1-2% of all breast cancers. It is often diagnosed in younger women and is associated with a more aggressive clinical course compared to other subtypes of breast cancer. The prognosis for HER2n breast cancer can vary, but it tends to be poorer than that of HER2-positive breast cancer, which responds well to targeted therapies like trastuzumab.

The molecular characteristics of HER2n breast cancer include HER2 overexpression without gene amplification, which can be detected using immunohistochemistry. The exact mechanisms underlying HER2n breast cancer are not fully understood, but it is believed to involve alternative pathways of HER2 signaling and activation.

Treatment for HER2n breast cancer typically involves a combination of systemic therapies, such as chemotherapy and targeted agents, along with surgical and radiation therapies as needed. The choice of treatment may depend on factors such as the patient's age, overall health, and the specific characteristics of the tumor. Ongoing research aims to better understand the molecular mechanisms of HER2n breast cancer and to develop more effective targeted therapies for this subtype.