CT and pathologic predictive features of residual mass histologic findings after chemotherapy for nonseminomatous germ cell tumors: can residual malignancy or teratoma be excluded?

Forty-eight patients with disseminated nonseminomatous germ cell tumors were studied retrospectively to determine whether initial pathologic features and pre- and post-chemotherapy computed tomographic (CT) features could be used to exclude malignancy or teratoma in residual masses that were excised after chemotherapy. Neither CT findings (residual mass size, attenuation, and degree of shrinkage during chemotherapy) nor type of primary testicular tumor cell was significantly correlated with malignancy or teratoma versus necrosis in residual masses. No significant correlation was demonstrated between the combined features of (a) the absence of teratoma in a histologic specimen of the primary testicular tumor and (b) greater than 90% shrinkage of masses during chemotherapy and the absence of malignancy or teratoma in residual masses as suggested in the literature. Of nine patients with both of these findings, two had malignancy and two had teratoma. Radiographic and pathologic features cannot be used to reliably exclude malignancy or teratoma in residual abdominal masses after chemotherapy for nonseminomatous testicular cancer.