Malignancy risk in patient with neurofibromatosis and autosomal dominant polycystic kidney disease.

Cancer appearance in some inherited diseases depends on the interactions with other genes. Lung cancer is rare in neurofibromatosis and has not been reported in Caucasian population. In this paper, we present the case of lung adenocarcinoma in a patient with neurofibromatosis, pseudoarthrosis of tibia, and autosomal dominant polycystic kidney disease. Cytogenetic analysis of the pleural effusion showed chaotic cleavage and constitutional inversion of chromosome 9, transmitted from the mother. Family investigation revealed two autosomal dominant diseases, neurofibromatosis and polycystic kidney disease in the same family. These findings suggest that the second autosomal dominant disease in the family and inversion of chromosome 9 contributed to the severity of neurofibromatosis and patient's risk to malignancies.