A group of patients with cardiac
myxoma who have a heritable syndrome involving skin
myxomas, endocrine
tumors, and
lentiginosis--the complex of
myxomas, spotty pigmentation, and endocrine overactivity--has been described previously. Patients with the complex had cardiac
myxomas at an early age (average, 26 years) with frequent multiple
myxomas (53%) and recurrent cardiac
myxomas (22%); however, no histologic differences were noted when these
tumors were compared with sporadic cardiac
myxomas. In the present study,
deoxyribonucleic acid flow cytometric analyses of 35 cardiac
myxoma specimens were correlated with clinical findings (mean duration of follow-up, 13 years). Among 30 patients with sporadic (nonfamilial) cardiac
myxoma, 24 (80%) had a normal (
deoxyribonucleic acid diploid) ploidy pattern, and six (20%) had an abnormal (
deoxyribonucleic acid tetraploid) pattern. Specimens from each of the five patients with the complex had abnormal
deoxyribonucleic acid tetraploid patterns (p = 0.002 compared with the sporadic
myxoma group). Further, all four patients who had recurrent cardiac
myxoma had an abnormal
deoxyribonucleic acid ploidy pattern (p = 0.007 compared with patients with nonrecurrent
myxomas). Unlike conventional histologic examination, the ploidy pattern of cardiac
myxomas seems to be sensitive for detecting biologically unusual
tumors, and a
deoxyribonucleic acid tetraploid pattern suggests a high risk of recurrence.