Intraplacental smooth muscle tumor. A case report.

BACKGROUND

Chorioangioma is the leading diagnosis for circumscribed placental lesion noted on ultrasound. Other rare intraplacental tumors may have a significant clinical impact on the mother and fetus.

CASE: An intraplacental, hypoechoic area consistent with chorioangioma was noted on ultrasound examination at 17 weeks' gestation. The lesion remained stable in size throughout gestation, with no evidence of fetal hydrops or polyhydramnios. At term, a live-born male infant was delivered vaginally, followed by spontaneous expulsion of the placenta. Histologic examination of the placenta revealed an intraplacental, potentially malignant smooth muscle tumor. Six weeks postpartum, total abdominal hysterectomy and pelvic node sampling were performed. No residual disease was found on the final histologic examination.

CONCLUSION

Although ultrasound differentiation is difficult, rare nontrophoblastic tumors should be considered in the differential diagnosis of placental masses. To our knowledge, this is the first report of such a lesion in the placenta.