Highly cellular samples (eg, tonsil, lymph node) can be very concerning. Remember that lymphocytes have little cytoplasm and there is not nearly the cellular material between cells as with other tissues. For this reason, the hematoxylin does not have to compete with the eosin. The compact nature of the cells also concentrates the DNA, giving these highly cellular tissues the appearance of being overstained, when in reality, they may simply need to be sectioned thinner.
Note the difference between the gross staining intensity of the lymph node and the kidney. The high cellularity of the lymph node gives the appearance of an overstained slide.
