NCIt definition : A general term that refers to a TNM finding of cancer metastases in several regional
lymph nodes. The definition of N2a TNM finding depends on the specific type of cancer
that it refers to; for example, for breast cancer it refers to metastases in 4 to
9 axillary lymph nodes (at least 1 tumor deposit greater than 2.0 mm); for cutaneous
melanoma it refers to micrometastases in 2-3 regional lymph nodes; for colorectal
cancer it refers to metastases in 4-6 regional lymph nodes.;
Currated CISMeF NLP mapping