The authors report the first results concerning the systematic use of "immunological monitoring" in patients suffering from well-developed laryngeal cancer. The authors have also studied, in 50 cases in different stages of development, the activity of T-cells using the cutaneous tests (BCG, PPD, PHA and SK-SD), the E-rosette test and the PHA-induced lymphocytic blastization test (it is well known that the T-cells are responsible for a cytotoxic effect against neoplastic cells). The authors have also studied the activity of B-lymphocytes by means of the EA and EAC rosette test and of IgG, IgA, IgM and complement serum titles. They have observed a progressive depression of the T-cell activity after surgical intervention, whereas the B-cell activity in several cases tends to increase. The authors discuss these immunological results and the possibility that these findings may represent the basis for a complementary immunotherapy following the surgical treatment and/or radiotherapy or chemotherapy. Finally, the authors discuss the possibilities and the limitations of these immunological methods from the point of view of clinical application.