293 - L’incremento della concentrazione sierica della proteina S-100 è un marcatore di metastasi nel melanoma maligno? Quattro anni di esperienza

M. Governa, R.M. Dorizzi, A.Tambuscioa, C. Monesea, A. Ferrari, P. Rizzotti, D.Barisoni. Background. The incidence of malignant melanoma greatly increased in the recent years and the follow up of disease is plagued by many relapses. S-100 protein is found in several cells of neuroectodermal origin. Serum S-100 concentration has been proposed as biochemical marker in malignant melanoma since it is related with the progression of the diasese. Methods. From October 1999 to October 2003, S- 100 serum concentration was measured in 880 blood samples obtained from 178 consecutive patients admitted for histologically confirmed malignant melanoma S-100 serum concentration was measured by an assay based on three monoclonal antibodies against bovine S-100 protein B-subunit, using an automated chemiluminescence analyzer (Liaison, Diasorin, Saluggia, Italy). This method is much faster (requiring less than an hour) compared to the previously available technology which has been employed in most of previous studies in this field Results. Seventeen out of 178 patients (9.55%) had local or distant metastasis. In 14 of them (82.35%), S-100 levels were higher then 250 ng/L (decision level) when disease progression was detected. Furthermore, five patients showed that a renewed rise of S-100 concentration reflected a new tumour recurrence. Conclusions. The present study hints, as previously reported, the rise of S-100 B protein in serum patients with malignant melanoma. The modern chemiluminescence analyser employed in our study is reliable and fast, allowing to shorten the assay time.