What does the "M" in TNM staging stand for?

In TNM staging, the "M" specifically refers to the presence of metastasis. This is a critical component of cancer staging that indicates whether cancer cells have spread from the primary tumor to other parts of the body. Accurate assessment of metastasis helps healthcare providers determine the extent of the disease, which is crucial for developing appropriate treatment plans and predicting prognosis. Understanding the status of metastasis provides vital information about how advanced the cancer is, influencing decisions related to surgical options, chemotherapy, and other therapeutic approaches.

The other options focus on aspects such as tumor margins, management plans, and morphological characteristics, but they do not capture the specific role of "M" in the context of TNM staging, which is focused exclusively on the spread of cancer beyond its original site.