Higher incidence of malignant neoplasms after heart transplantation for treatment of chronic Chagas' heart disease.

BACKGROUND

Heart transplantation is a new therapeutic procedure to treat heart failure resulting from Chagas' disease. Experimental studies have demonstrated neoplastic effects of benznidazole, which is used for treatment of Trypanosoma cruzi infection. We compared the incidence and characteristics of neoplasia after heart transplantation for treatment of chronic Chagas' disease with those of other diseases.

METHODS

Sixteen patients with Chagas' disease and 75 patients with other diseases underwent heart transplantation. Benznidazole was administered to 14 patients with Chagas's disease either for prophylaxis (4 patients) or for treatment of Chagas' disease reactivation (10 patients).

RESULTS

The survival rate of patients in the nonchagasic group was 90% at 1 year and 82.4% at 2 years, and the survival rate in the chagasic group was 63% at 1 year and 57% at 2 years. Six of 16 patients (37.5%) with Chagas' disease had malignant tumors after a mean follow-up time of 25.3+/-2.1 months in contrast to 2 of 75 patients (2.7%) in the nonchagasic group after 34.6+/-3.6 months of follow-up. In the chagasic group, lymphoproliferative disorder was diagnosed in three patients, Kaposi's sarcoma in two, and squamous cell carcinoma in one patient. Reactivation of T. cruzi infection was diagnosed in all patients who had lymphoproliferative disorder. One patient without Chagas' disease had lymphoproliferative disorder in the lung, and another had malignant schwannoma affecting the skin.

CONCLUSIONS

We found a higher incidence of malignant neoplasia after heart transplantation for treatment of chronic Chagas' disease. It is likely that the neoplasia is the result of chronic infection with an immunomodulator protozoan, immunosuppression, reactivation of the T. cruzi infection, or the toxicity of therapeutic intervention with benznidazole.