Congenital mesoblastic nephromas are rare renal tumours that are encountered in paediatric age group. A term female neonate at the end of first week of life presented with bilateral lower limb swelling. On radiological evaluation, ultrasonography revealed an intra-abdominal mass which was managed with radical nephroureterectomy. Histopathological examination confirmed a diagnosis of congenital mesoblastic nephroma of mixed subtype.
UNASSIGNED: case reports; congenital mesoblastic nephroma; kidney neoplasms; nephrectomy.

暂无摘要。

Congenital mesoblastic nephroma is a rare pediatric renal tumor and has been reported in patients presenting with palpable abdominal mass, arterial hypertension, hematuria, polyuria, or hypercalcemia. Here we present the case of a 1-month-old neonate with suspected parathyroid hormone (PTH)-related peptide (PTH-rp)-mediated severe hypercalcemia revealing congenital mesoblastic nephroma. Preoperatively, hypercalcemia was corrected with hydration, furosemide, pamidronate, and low-calcium infant formula. Unilateral nephrectomy led to the resolution of hypercalcemia, transient hyperparathyroidism, and transient vitamin D and mineral supplementation. We conclude that congenital mesoblastic nephroma can secrete PTH-rp that can cause severe hypercalcemia.

BACKGROUND: Fetal congenital mesoblastic nephroma (CMN) is a rare renal tumor, characterized by polyhydramnios, premature birth, and neonatal hypertension. In the prenatal stage, it is particularly difficult to diagnose CMN either by ultrasonography or magnetic resonance imaging (MRI). Thus, CMN is frequently detected in the third trimester in the clinical scenario.
UNASSIGNED: A 29-year-old G2P0 pregnant woman took routine prenatal examinations in our hospital. The fetal right kidney abnormality was not observed after 2 systematical ultrasonic examinations (at 24 and 31 weeks of gestation respectively), and only an increase was noticed in the amniotic fluid index (from 19.3 to 20.8 cm).
METHODS: CMN was detected by antenatal ultrasonography and MRI as a fetal right renal mass at 35 weeks of gestation in our hospital.
METHODS: The pregnant woman was admitted at a gestational age of 38 weeks and 5 days due to alterations in renal function. Further, the pregnant woman was administered with \"oxytocin\" to promote delivery, and the neonate underwent a right nephrectomy on the 9th day after birth.
RESULTS: The pathological examination confirmed a cellular type of right CMN. The neonate recovered well after operation without adjuvant treatment. During 6 months of follow-up, the neonate grew well and showed no signs of recurrence or metastasis.
CONCLUSIONS: Polyhydramnios detected during prenatal examination required attention due to the risk of malformation of fetal urinary system. Prenatal ultrasonography combined with MRI could not only clearly identify the origin of the tumor, but also distinguish the correlation between the tumor and adjacent structures, thereby leading to early diagnosis and favorable prognosis.

Congenital mesoblastic nephromais a rare tumour found in neonates, with a very small number of cases diagnosed prenatally. We report a case of a fetal renal tumour suspected at 28 weeks\' gestation on routine ultrasound. Prenatal follow-up revealed a severe polyhydramnios at 32 weeks\' gestation subsequent amniodrainage was undertaken. She delivered at 34+5 weeks\' gestation, after spontaneous premature rupture of membranes.

Although congenital infantile fibrosarcoma (cIFS) is a rare soft tissue sarcoma among children, it constitutes one of the most common soft tissue sarcomas during the first year of life. Congenital mesoblastic nephroma (CMN) is the most common benign renal tumor usually developing during the first 3 months of life. cIFS and cellular type CMN (cCMN) share not only similar histopathologic features but identical molecular genetic abnormality including the ETV6/NTRK3 fusion gene. Here, we report an unusual case of cIFS occurring with cCMN.
An 18-month-old girl presented with a 1-month history of abdominal distension and a few days\' history of a palpable abdominal mass. A large heterogenous mass sized 9.0×11.2×11.6 cm on the right side of the abdomen and an isolated heterogenous lesion sized 4×4.5 cm within the right kidney were noted from the imaging study. Pathologic findings were consistent with cIFS and cCMN of the right kidney. In addition, both pathologic specimens contained the ETV6/NTRK3 fusion gene.
Although cIFS and cCMN share similar histopathologic features and molecular genetic abnormality, simultaneous occurrence of these 2 types of tumor is exceedingly rare. To our knowledge, this is the first unusual case report of concurrent cIFS and cCMN.

Cystic nephroma is a rare and benign renal tumour of unknown origin, usually diagnosed in the first years of childhood or during adult life. To our knowledge, there are no records in the literature of this particular tumour being descried prenatally. We present a case of a fetus diagnosed with cystic nephroma on 16 weeks of gestation. The renal tumour was evaluated by prenatal ultrasound, post mortem with 7T magnetic resonance imaging, and conventional autopsy.

Congenital mesoblastic nephroma (CMN) is the most common renal tumor of infancy; however, it occurs infrequently with an incidence of 1 : 125,000. The cellular and classical variants are the most common subtypes of tumors, with a mixed variant occurring infrequently. We describe two cases of mixed variant CMN, which presented within days of each other differing in their clinical behavior. The first case followed a typical course, previously described in the literature, while the other deviated significantly. Traditionally, CMN presents as large abdominal mass in the neonatal period associated with a paraneoplastic syndrome, which can result in hypertension or hypercalcemia. Surgical resection is curative in most cases and long-term prognosis is excellent. Hypertension rarely persists after removal of the tumor, but remained in one of our two patients.

The most common nonencapsulated solid renal tumor in the neonatal period is congenital mesoblastic nephroma. Mesoblastic nephroma is a solid lesion originating within or extending from the renal parenchyma. These tumors proliferate rapidly, typically within 3-6 months after birth. Mesoblastic nephromas are stratified by classification as either classical (benign) or atypical (malignant); masses composed of both benign and malignant cells are also reported. The hallmark clinical manifestation of mesoblastic nephroma is a palpable abdominal mass, which may be accompanied by hypertension, hypercalcemia, hematuria, and polyuria. Differentiating between benign and malignant renal tumors is essential to invoke a timely, evidence-based management and treatment plan. With appropriate surgical intervention in a timely manner, prognosis is excellent and mesoblastic nephroma is considered curable. We present a case involving a premature infant with congenital mesoblastic nephroma with discussion of embryology, pathophysiology, diagnostic, management, and prognostic implications for the neonate and family.

Congenital mesoblastic nephroma (CMN) is the most frequent renal neoplasm of newborns and young infants. Four cases presenting with hemorrhagic manifestations have been reported in the English literature (Hu et al, 2006; Bolande et al, 1967). We report the unusual clinical and radiographic findings of a 2-day-old neonate with hematuria secondary to a CMN. The first ultrasound was equivocal. Repeat ultrasound followed by magnetic resonance imaging confirmed the diagnosis. He underwent a right nephroureterectomy with histopathology revealing a cellular variant of CMN without classical translocation (t12:15). Neonates presenting with hematuria require close follow-up and serial imaging to rule out occult renal tumors. Classical translocation may not be demonstrable in all the cases.