1. Scientists have always dissected lymph nodes nearby a cancerous tumor to see if the cancer has begun to spread to other areas of the body. The most obvious nearby lymph node is chosen. Scientists have discovered that in women with breast cancers that are 5 cm in diameter or smaller, nothing is gained by additional lymph node dissections in the axillary region (armpit) of the body. Dissecting the node nearest the tumor provides adequate information by itself.