THE MANNER OF EXTENSION OF CANCER

If we stop to consider the actual rate at which lymph must travel in the finer lymphatics, it becomes at once evident that the velocity must be far too low to permit it to have much effect in washing cancer cells or similar objects from one place to another. Furthermore, the very fact that in cancer the lymphatics are extensively blocked by cancer growth must make the rate of lymph flow rather less than normal. Nevertheless the assumption and the teaching until quite recently have been almost universal that cancer cells were washed from the primary growth to the regional glands by the lymph stream. By his demonstrations of the continuity of cancer growth from the primary tumor into the regional lymphatic channels, spreading centrifugally by direct extension and largely independently of any washing away of cells, Handley did a great service to surgical pathology and surgical practice, for he