Current status and future prospects for adjuvant therapy of melanoma

Advances in the treatment of melanoma have resulted mainly from improved surgical management of the primary tumour assisted by a greater appreciation of major prognostic factors in the natural history of the disease. Further improvement in the treatment of melanoma will depend largely on introduction of methods to prevent recurrence of the disease. The present review discusses criteria for selection of patients with a high risk of recurrent disease and the adjuvant treatment that has been used in past studies to prevent recurrences. With few exceptions various regimens of chemotherapy, non-specific immunotherapy with bacterial products or combinations of these treatments have not increased disease free or survival periods. Immunotherapy with various sources of melanoma antigens or with viral lysates of melanoma cells have produced encouraging results in uncontrolled studies and require further evaluation. Several advances appear to provide scope for new initiatives in immunotherapy. These include an appreciation of the role of suppressor cells in regulation of immune responses against tumour cells and possible methods to inhibit their activity. A second is the definition of various lymphokines involved in generation of immune responses (particularly interleukin 2) and development of in vitro methods for large scale production of these factors. Thirdly, methods are becoming available to define the heterogeneity of tumour cells in terms of cell surface antigens or their release of soluble factors which may help select treatments appropriate to each patient.