Expression of IL4 Induced Gene 1 in Patients With Cutaneous Melanoma: Value in Prognosis and/or in Predictive Response to Immune Checkpoint Inhibitors

The incidence of cutaneous melanoma is increasing, but the current prognostic parameters mainly based on histological data are insufficient to identify patients with high risk of recidive. In addition, current immunotherapies using PD-1 and/or CTLA-4 antibodies have long-lasting tumor control in a substantial fraction of patients but identify new markers of treatment resistance need further investigations. Clinical data highlight enzymes involved in amino acid catabolism as new potential prognostic markers in human melanoma. Among those, the IL4I1 phenylalanine oxidase may be a new relevant marker and may represent an easily targetable molecule for cancer immunotherapy. The current retrospective study is designed to evaluate whether a high proportion of IL4I1 positive cells within the primary tumor and/or sentinel lymph nodes allows to predict the risk of cancer recurrence from the clinical diagnosis. Immunofluorescence and immunohistochemistry will be performed. The longitudinal study of IL4I1 positive cells in the blood and cutaneous metastasis od patients will start before and after (three months and 1 year (or before in case of treatment resistance) the treatment with targeted therapy and/or immunotherapy as a first line. Treatment will be administered on an outpatient basis. No investigational or commercial cancer directed agents or therapies other than those described below may be administered. It is designed to evaluate whether patients that resist to treatments exhibit a high proportion of IL4I1 positive cells and how is regulated the enzyme in the course of the treatment.