Lectin histochemistry of classic and spermatocytic seminoma.

Six spermatocytic and 13 classic seminomas were studied histochemically with fluorescein isothiocyanate-labeled lectins. Wheat-germ lectin and succinyl concanavalin A reacted with all 19 tumors, whereas other lectins bound to some, but never to all, tumors in either group. Soybean lectin reacted with seven of 13 classic seminomas but with none of the spermatocytic seminomas. On the other hand, Maclura pomifera lectin reacted with two of six spermatocytic and with none of the classic seminomas. Our data thus illustrate some differences between classic and spermatocytic seminomas, but no diagnostic or pathognomonic pattern of lectin binding could be discerned. Neither classic nor spermatocytic seminomas (with a single exception) reacted with the lectins that do not react with normal spermatogenic cells. Spermatocytic seminomas did not react with eight lectins typically recognizing spermatids and spermatozoa. Thus, our data do not support the earlier contentions that spermatocytic seminomas contain malignant equivalents of cells in advanced stages of spermatogenesis.