Honeycomb appearance of fetal myofibromatosis.

Abstract

Infantile myofibromatosis (IM) is a benign neoplasm of infancy, with an incidence of 1:150 000, that presents in 90% of cases before 2 years of age and is rarely encountered in newborns. The mortality rate is 15%, and death is usually attributable to generalized visceral multicentric disease1-4. Prenatal diagnosis of IM gives the option of termination of pregnancy to parents in communities that accept such a choice. We present the case of a fetus with abnormal sonographic findings leading to postnatal diagnosis of congenital IM. To the best of our knowledge, this is the first case of IM with diffuse multiorgan involvement reported in the English medical literature. The proband was the firstborn of non-related parents of Jewish Ashkenazi and non-Jewish descent. The mother (a 23-year-old primigravida) was healthy and had unremarkable medical history. On the father's side (28 years old), the aunt reported ‘skin hemangiomas’ in infancy that had resolved spontaneously. Routine prenatal follow-up was unremarkable until 34 + 4 weeks of gestation, when an ultrasound examination showed masses of unknown origin over the fetal organs. A detailed ultrasound examination performed at our institution confirmed multiorgan involvement, with masses predominantly in the lower extremities (Figure 1), heart, abdominal cavity and neck. Normal Doppler studies were recorded in the major fetal arterial and venous circulations as well as normal amniotic fluid volume and unremarkable appearance of the placenta. The parents were offered genetic counseling and the option of pregnancy termination. They opted for delivery, which was performed by Cesarean section. The neonate weighed 2475 g (50th percentile). After birth, dysmorphic features were noted, including upslanting eyes, palpebral fissures, depressed nasal bridge, micrognathia and microcephalus. Generalized multiple subcutaneous lesions were palpated in the right side of the neck, back, thorax and right and left abdominal walls. The newborn underwent a comprehensive workup in the neonatal intensive care unit, including echocardiography and magnetic resonance imaging of the brain and neck, all of which supported the prenatal findings (Figure 2). A biopsy of a lesion on the right abdominal wall was consistent with IM. Eight days following delivery, the newborn developed late-onset sepsis. No surgical options were available due to the extent of the disease and, after a trial of treatment with tyrosine kinase inhibitors, the infant died from cardiac failure. The present case represents a developmental progressive disease with poor outcome that was diagnosed only in the third trimester. Due to the severity of IM, it is of high importance to make the diagnosis prenatally as early as possible. An early prenatal finding of soft tissue appearance resembling honeycomb may indicate IM. In such cases, physicians should recommend parents to undergo genetic consultation, discuss prognosis and treatment options in case of birth, or consider termination of pregnancy when relevant.