Three years after replacement of the left first metatarsophalangeal joint with a silicone prosthesis, a patient noted enlargement of a left femoral lymph node. Fine needle aspiration of the node revealed a foreign body giant cell reaction to particulates morphologically compatible with silicone elastomer. This finding suggests the potential utility of fine needle aspiration in the evaluation of patients' responses to a variety of foreign materials used in prosthetic devices and as pharmaceuticals.