Case presentation: We report a male term newborn with a congenital macrocephaly, 3.5 standard deviation
above median noted at birth. The antenatal history, including ultrasonography was
reported to be normal. The head circumference was measured between 10th and 50th percentile
at 21 weeks 3/ 7 and 30 weeks 5/ 7, respectively. Postnatal adaptation was complicated
by poor respiratory effort and the baby had to be intubated at 8 minutes of age.
On clinical examination at admission to our unit we noted: A wide and tense anterior
fontanel, splayed sutures without external bruising or swelling, a normal inspection
of the spine and a provocable gag reflex, bilaterally 3mm wide and isoreactive pupils
and general hypotonia with all extremities spontaneously and symmetrically moved were
described.
Initial imaging investigation was performed with a head ultrasound. There was a large
intra- parenchymal mass in the right cerebral hemisphere with a compressed right lateral
ventricle and a massively dilated right lateral temporal horn, as well as an enlarged
and laterally displaced right frontal horn. All ventricles showed signs of ventriculitis.
These findings were investigated further with a CT scan and a MRI. The initial differential
diagnosis included teratoma and neuroblastoma with a communicating hydrocephaly. A
decompression had to be performed and the histology showed the findings of a Primitive
Neuro Ectodermal Tumor (PNET) or neuroblastoma. The cytogenetic analysis showed a
previously reported abnormal clone with structural rearrangement involving chromosomes
1 and 15 and tetraploidy with unstable number of chromosomes (ISCN Nomenclature: 92,
XXYY,? t (1;15) (p36; q24)/ 46, XY/ 92, XXYY), a mutation previously described.
Discussion and review of the literature: The reported incidence of neonatal brain tumors is between 1.4 and 3.6 per 100,000
live births. The most commonly reported findings in a review of 250 cases of previously
published congenital brain tumors were macrocephaly (28.7%), hydrocephalus (17.3%),
detection by imaging pre- or postnatally (12.2%) and stillbirth (10.4%). Classically
reported signs of intracranial hypertension reported in older children are very rarely
present. In a previous review of 230 cases, 23 patients had an associated dysmorphic
feature of various and nonspecific type.
Conclusion: Congenital macrocephaly should be investigated carefully. The most frequent pathologies
found, include hydrocephaly and intra- or extracranial hemorrhage. An initial head
ultrasound seems to be adequate as a screening method. Should there remain some uncertainty
after a CT scan, better imaging results are obtained with a MRI and when a tumour
is found, the definite diagnosis will be secured by histopathology.
Key words: macrocephaly, hydrocephalus, neuroblastoma, PNET
