Introduction Fetal suprarenal masses are diagnosed incidentally on antenatal ultrasound. Differential diagnosis includes adrenal haemorrhage, neuroblastoma of the adrenal medulla, adrenocortical adenoma and pulmonary sequestration. Post-natal follow-up and characterisation is necessary to determine appropriate management.1,2

Method Cases were identified from the fetal medicine and obstetric databases. Neonatal unit discharge summaries were reviewed for outcome data.

Results 11 cases of fetal suprarenal mass are presented. Five right sided and six left sided masses were diagnosed. In three cases multiple fetal abnormalities were concurrently diagnosed, for two of these the parents chose to obtain fetal karyotype which was normal. Fetal MRI was carried out in 3 cases, allowing characterisation of an hepatic cyst, an adrenal mass and a multiloculated cyst in the base of the left lung.

One fetocide was performed where the fetus also had severe ascites. There were 10 live births, with one neonatal death from tricuspid atresia. Postnatal imaging was available for seven of the livebirths, one mother refused further imaging.

One case of left adrenal haemorrhage, one of isolated pulmonary cyst and two of neuroblastoma were confirmed postnatally, with resolution of the masses in the other three cases (possibly indicating resolved areas of haemorrhage). Follow-up data was not obtainable in the remaining cases.

Discussion The differential diagnosis for fetal suprarenal masses include adrenal lesions, hepatic or pulmonary masses and unusual renal abnormalities. The most important condition to exclude is neuroblastoma. The use of fetal MRI and high resolution ultrasound allows characterisation of the masses prenatally.