Anthracycline induced myocardial damage. An analysis of 16 autopsy cases.

The hearts of 16 autopsy cases with a past history of administration of anthracycline antitumor drugs (DNR, ADR and ACM) and a sign of cardiac failure were investigated morphologically. In macroscopic observation, both ventricles were more or less dilated with thinning of the ventricular wall. Mural thrombi were recognized in the left ventricle of 2 cases. Histologically, the myocardial lesions could be roughly classified into two groups, a) myocardial changes in cases with rapidly developed cardiac failure (acute form), and b) myocardial changes in cases with relatively slowly developed cardiac failure. In acute form, myocardial cells showed marked swelling with dilatation of central sarcoplasmic core, marked reduction of myofibrils, vacuolization of cytoplasm and enlargement of nucleus accompanied by distinct large nucleolus. Necrotic myocardial cells were scattered among these degenerative cells. These degenerative and necrotic cells were distributed diffusely in both ventricular walls, but were more frequent in the left ventricular wall than in the right one. Inflammatory cell infiltration was also recognized not only in the myocardium, but also in the endocardium and epicardium. In chronic form, on the other hand, atrophy and attenuation of myocardial cells with a hypereosinophilic change of the cytoplasm and an increase in number of brown pigments, and marked reduction of myocardial cells were most common findings. These changes of chronic form, however, could not be identified as the specific changes of anthracycline cardiotoxicity. Fibrosis was hardly seen in the myocardium of both acute and chronic forms.