Immunophenotyping of tumor-infiltrating lymphocytes in the second regression phase revealed significantly more cytotoxic (CD4−/CD8+) T-lymphocytes compared to peripheral blood, whereas percentages of the T-helper (CD4+/CD8−) lymphocytes and double-positive (DP) CD4+/CD8+ T-lymphocytes were reduced. Here, CD4 is linked to neoplasm.