Chinese medicine has some history of treating conditions that are similar to, or may be, lymphedema. Lymph nodes were indirectly recognized, even in ancient times, as areas that easily become lumpy, but lymph was not known in the same sense that it is recognized in modern medicine. The condition of lymphedema fits the traditional category of phlegm-damp accumulation. The fluid swelling would, by itself, lead one to classify the disease as a dampness accumulation (corresponding directly to the Western term edema). The phlegm aspect of the condition is related to the thickness of the fluids involved. As we know from modern research, lymph is a somewhat milky fluid that replenishes the blood with chyle (emulsified fat), erythrocytes (red blood cells), and leukocytes (white blood cells); it also carries protein debris. A more watery accumulation based on a less-dense fluid, as occurs in cases of pitting edema, would be considered a moisture accumulation but not a phlegm-damp accumulation.
By Abdullah Sarhan (Own work) [CC BY-SA 4.0 (http://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons