Two cases of tongue cancer treated with intra- and peri-tumoral injection of recombinant interleukin-2 alone: immunohistochemistochemical considerations to clinical tumor response.

SUBJECTS AND METHODS: Two cases with stage II tongue cancer who exhibited different responses to intra- and peri-tumoral administration of rIL-2 alone are presented. Special consideration is given to the relationship between tumor responses to rIL-2 and clinicopathological and immunohistopathological findings.

RESULTS: The patient who responded completely to treatment showed an exophytic tumor growth pattern, low-grade cancer invasion, and predominant infiltration of CD8+ lymphocytes over CD4+ lymphocytes in cancer cell nests. The non-responder showed endophytic tumor growth, high-grade cancer invasion, and uniform distribution of both CD4+ and CD8+ lymphocytes in cancer cell nests.

CONCLUSIONS: Distribution of adequate amounts of T lymphocytes subsets may be necessary in order for good tumor response to biotherapy with rIL-2; other clinical and histopathological variables predicting the effect for cancer chemotherapy remain to be identified.