del(6)(q12q15) as the sole cytogenetic anomaly in a case of solitary infantile myofibromatosis

We describe a case of light microscopically typical solitary, infantile myo fibromatosis in a 6-month old boy. The myofibroblastic differentiation of t he tumor was supported by immunohistochemical and ultrastructural analyses. Cytogenetic and FISH analyses revealed a pseudodiploid karyotype with an i nterstitial deletion of the long arm of one chromosome 6, del(6)(q12q15), a s the sole anomaly. The results demonstrate the usefulness of cytogenetics and FISH in distinguishing this type of lesion from infantile fibrosarcoma. To the best of our knowledge this is the first cytogenetic analysis of sol itary infantile myofibromatosis.