Two young patients with similar radiographic manifestations of massive opacification of left hemithorax with scattered calcification highly suggestive of mediastinal teratocarcinoma are reported. By biopsy, one patient was proved to have teratocarcinoma and the other patient was proved to have Hodgkin's disease. Retrospective review indicates that spontaneous neoplastic calcification in Hodgkin's disease, though rare, can occur prior to therapy. Computed tomography is useful in distinguishing such cases of Hodgkin's disease from teratocarcinoma by demonstrating the involvement of the posterior mediastinum and homogeneous density. © 1985.
