Prenatal diagnosis and postnatal management of congenital mesoblastic nephroma: A case report and literature review

Abstract

BackgroundCongenital mesoblastic nephroma (CMN) is a rare renal tumour in children, the most common kidney tumour in the neonatal period. It can be divided into three types, classical, cellular and mixed.Case presentationA 31-year-old Chinese woman had no apparent foetal abnormality in regular prenatal care during the first and second trimesters. At 33 weeks of gestation, a solid mass in the right kidney was noted with echoes similar to liver and hypervascularity. It grew larger during late pregnancy. The infant was transferred to have a radical nephrectomy on the 9th day after birth. The postoperative histopathological result indicated classical CMN.ConclusionCMN could be detected prenatally, mainly during late pregnancy. The postnatal outcome is good.

A massive primary congenital mesoblastic nephroma was successfully managed through open total nephrectomy: a case report

“…Polyhydramnios affects 15–36.4% of CMN patients and increases the risk of preterm delivery. Polyhydramnios can be caused by excessive blood perfusion in the kidney and constriction of the surrounding intestine 4 , 8 . In this case, an excessive amniotic fluid was discovered in the third trimester that led to premature labor.…”

“…The first definitive sign that a renal lesion is present is polyhydramnios, which causes preterm delivery 3 . Ultrasonography (US) can only identify 11–14% of cases 4 . This tumor may lead to major complications such as polyhydramnios, neonatal hypertension, preterm labor, and hydrops fetalis 2 .…”

Diagnostic magnetic resonance imaging characteristics of congenital mesoblastic nephroma: a retrospective multi-center International Society of Pediatric Oncology-Renal Tumor Study Group (SIOP-RTSG) radiology panel study

“…Histologically, three subtypes have been described [ 9 ]. The classic type consists of bland spindle cells, with few mitoses and no apparent hemorrhage and necrosis [ 2 , 7 , 21 – 23 ]. In contrast, the cellular type shows a high mitotic index and invasive growth pattern with areas of hemorrhage and necrosis [ 2 , 3 , 7 , 17 , 22 ].…”

“…The classic type consists of bland spindle cells, with few mitoses and no apparent hemorrhage and necrosis [ 2 , 7 , 21 – 23 ]. In contrast, the cellular type shows a high mitotic index and invasive growth pattern with areas of hemorrhage and necrosis [ 2 , 3 , 7 , 17 , 22 ]. In general, if both histological patterns are present, the lesion is classified as mixed type [ 2 , 23 , 24 ].…”

“…Based on previous case reports and small retrospective studies, congenital mesoblastic nephroma is typically described as homogeneous and isointense to normal renal parenchyma [ 4 , 7 , 12 , 14 , 33 ]. The cellular type seems to be more heterogeneous, making differentiation from malignant tumors more difficult [ 3 , 6 , 8 , 21 , 28 , 33 – 37 ].…”