Poor prognosis for mucin-producing Wilms' tumor.

This report describes two cousins with Wilms' tumor and mucin detected in the sera with rapidly fatal courses. A review of the literature reveals five additional reported cases of Wilms' tumor where mucin was observed in the sera. The patients in this report are similar to those previously reported in that all had metastatic disease at diagnosis, and four of five died within one year of diagnosis. Both the extent of disease at diagnosis at the poor response to therapy in these two cases, and those from the literature suggest that evidence of mucin production may indicate poor prognosis in Wilms' tumor. In addition, evidence is reviewed that mucin itself may contribute to a rapid tumor growth and metastases. The genetics of Wilms' tumor and familial nature of these cases is also discussed.