[In situ analysis of distribution of immunocompetent cells in tumor's local draining lymph nodes].

Aim: To observe the distribution of immunocompetent cells (ICCs) in tumor's local draining lymph nodes (LDLN) at different stages of disease including non-metastasis, micro-metastasis and late metastasis.

Methods: 71 LDLN from 22 breast cancer, 28 LDLN from 7 gastric carcinoma were analysed by using catalyzed signal amplification (CSA) immunohistochemical staining. Monoclonal antibodies (mAbs) to perforin, granzyme B, CD8, CD56, CD68, S-100, CD134 and CD25 were used to detect the amount and functional change of ICCs.

Results: Paracortical hyperplasia and sinus histocytosis was mainly observed in tumor's LDLN. As it was reported, the density of S100(+) dendritic cells (DCs) was decreased as the draining lymph nodes became tumor-containing from the status of tumor free (P<0.05), and the morphology of DCs turned to be inactivated. As the lymph nodes were invaded by tumors, the densities of CD134(+) lymphocytes and CD25(+) cells were significantly increased (P<0.01). Furthermore, there was a significant trend of decreasing in the number of activated cytotoxic T lymphocytes (granzyme B(+) cells) in LDLN as tumor progressed from non/micro-metastasis, early metastasis to advanced stage metastasis (P<0.01). There was no obvious difference in distribution of ICC between non/micro-metastasis sentinel lymph nodes and non-sentinel lymph nodes.

Conclusion: The dynamic change of the ICCs in LDLN implied that immune response of tumor bearing host tends to be inhibited with the progress of tumors.