Two cases of tongue cancer treated with intra‐ and peri‐tumoral injection of recombinant interleukin‐2 alone: immunohistochemical 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 rlL‐2 alone are presented. Special consideration is given to the relationship between tumor responses to rlL‐2 and clinicopatholog‐ical 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 rlL‐2; other clinical and histopathological variables predicting the effect for cancer chemotherapy remain to be identified.