Tumour cell trapping in rat mesenteric lymph nodes

We describe a new experimental model of mesenteric lymph node metastasis in the rat, involving afferent mesenteric lymphatic inoculation of tumour cell suspensions via glass microcannulae. This model has been used to perform a series of experiments to investigate whether the rat mesenteric lymph node trapped tumour cells. Afferent mesenteric lymphatic inoculation of suspensions of transplantable sarcoma cells in inbred hooded Lister rats resulted in tumour growth in the inoculated lymph node in 100% of rats, with no tumour growth at any other site. The same procedure performed on rats which had previously undergone mesenteric lymphadenectomy resulted in growth of tumour in the lungs. Using 125Iododeoxyuridine (IDUR) labelled sarcoma cells we have shown that although radioactivity decreased significantly in the mesenteric lymph node up to 24 h following afferent lymphatic inoculation, there was no evidence that tumour cells reached thoracic duct lymph. We conclude that the rat mesenteric lymph node trapped sarcoma cells.