PERINODULAR INJECTION OF THYMOPENTINE (TP5) IN CUTANEOUS AND SUBCUTANEOUS METASTASES OF MELANOMA

The potential therapeutic efficacy of TPS in patients with cutaneous a nd subcutaneous metastases of melanoma was tested in a double-blind st udy comparing the drug and placebo injected perinodularly. Of the 47 n odules present in the 16 patients treated with TPS, 24 showed a measur able response, whereas only one out of 15 nodules in patients treated with a placebo showed a minor response (P = 0.02). In two patients tre ated with TPS a response of two nodules not perinodularly injected was . also observed. Sclerosis, CD45RO(+) cells and MIB 1(-) cells were mo re frequently observed in nodules treated with TPS than with placebo. (P = 8 x 10(-4); 0.03 and 0.01, respectively). Evaluating the trends o f these findings in nodules treated with placebo; with TPS-treated, no nresponding nodules; or with TPS-treated, responding, a positive trend was observed for sclerosis and CD45RO(+) cells (P = 5 x 10(-4) and 2 x 10(-5), respectively) and a negative one for MIB 1 cells (P = 2 x 10 (-3)). These preliminary data suggest that lymphoid cells associated w ith nodules regression are activated large lymphocytes (CD4SRO(+) and CD3(-)). Sclerosis might be interpreted as the final morphologic event , and reduction of proliferative activity (MIB 1(-) cells) as the cons eqence of cytolytic action.