In the TNM staging system, what does 'T' represent?

In the TNM staging system, 'T' specifically represents the size and extent of the primary tumor. This system is used globally to classify the severity of cancer, helping healthcare providers make informed decisions about treatment and prognosis. The 'T' category can include designations such as T0, indicating no evidence of a primary tumor, or T1-T4, which detail increasing size and depth of invasion into surrounding tissues. Accurately determining the size of the tumor is crucial because it plays a significant role in staging and directly influences treatment planning and patient management strategies. The classification focuses on how large the tumor has become and whether it has grown into nearby tissues, making it an essential factor in understanding the progression of the disease.