RESUMO
Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder that occurs once in 3,000 live births. Patients with NF1 are prone to develop malignancies, particularly neural tumors, that is, malignant schwannoma and glioma in adults. For non-neural tumors, the NF1 incidence is increased in rhabdomyosarcomas, leukemia, malignant melanomas, breast cancer, lung cancer, thyroid cancer, and other organ cancers. The NF1 gene seems to increase the risk for carcinogenesis. A case of NF1 associated with metachronous cancers, such as breast cancer (1991) and small-bowel leiomyosarcoma (1997), in the same patient is reported. Investigation of the patient's family revealed four further cases (offsprings) of multiple neurofibromatosis. The relevant literature on the subject is reviewed.