TNM staging is a crucial system used to assess the extent and severity of cancer, including breast cancer. Understanding TNM staging is vital for both patients and healthcare providers, as it helps determine the appropriate treatment and prognosis. Here’s a breakdown of TNM staging for breast cancer:

T – Tumor Size: The “T” in TNM represents the primary tumor’s size and extent within the breast. It is typically categorized into four stages:

TX: The primary tumor cannot be assessed.

T0: No evidence of a primary tumor.

T1: The tumor is small, usually less than 2 cm in size.

T2: The tumor is larger, between 2 cm and 5 cm.

T3: The tumor is larger than 5 cm.

T4: The tumor has grown into the chest wall or the skin of the breast.

N – Lymph Node Involvement: The “N” stage indicates whether cancer has spread to nearby lymph nodes. It includes:

NX: Lymph nodes cannot be assessed.

N0: No lymph node involvement.

N1: Cancer has spread to nearby lymph nodes, typically under the arm (axillary lymph nodes).

M – Metastasis: The “M” stage indicates whether cancer has metastasized or spread to distant organs. It includes:

MX: Distant metastasis cannot be assessed.

M0: No distant metastasis.

M1: Cancer has spread to distant organs, such as the lungs, liver, bones, or brain.

Combining the T, N, and M stages provides a comprehensive TNM stage, which guides treatment decisions and prognosis for breast cancer patients. Early detection and accurate staging are crucial for determining the most effective treatment plan and improving the chances of successful outcomes.