Case 27a

by Professor Chua & Dr. Ngo

A 12 month-old baby girl was referred by a private paediatrician because of a left proptosis and right subconjunctival haemorrhage (Figure 1a and b). The CT scan in the private hospital revealed a retroorbital mass (Figure 2a, b, c and d). The girl has been unwell for a few weeks with loss of appetite. She had normal right reflexes with a non-reducible left proptosis. Fundal examination was normal and there was no relative afferent pupillary defect.

Figure 1a and b. Left proptosis with right subconjunctival haemorrhage and some eyelid bruising.

Figure 2a, b, c and d. CT scan showing a retro-orbital mass arising from the lateral orbital wall.

The abdominal examination revealed abdominal mass and the patient was referred to the hospital paediatrician for further work-up. The abdominal ultrasound (Figure 3a and b) revealed a suprarenal mass and the CT scans (Figure 4a and b) showed extensive paravertebral mass extending from the level of left atrium into abdomen with chunky calcification noted within the mass. There was an abdominal mass extending retroperitoneally and across midline till level of bifurcation of common iliac vein. The liver and spleen were not enlarged.

Figure 3a and b. The ultrasound shows a large suprarenal mass. CT scan shows paravertebral mass.

Figure 4a and b. CT scans of the thorax and abdomen show large mass extending from the thorax

into the abdomen along the paravertebral region and into the retroperitoneal space.

a. What is the most diagnosis?

Neuroblastoma. It is a tumour of the sympathetic nervous system.

 

The presence of orbital mass with abdominal and/or thoracic mass is strongly suggestive of neuroblastoma. Neuroblastoma is second only to rhabdomyosarcoma as the most common malignant tumour of the orbit in children. In this patient, this was confirmed histologically by obtaining tissue from the abdomen which is more accessible than the retrobulbar mass and avoids trauma to important structures.

 

Neuroblastoma affects about 9 per million children and is responsible for 8-10% of all pediatric malignancies but accounts for 15% of deaths from cancer in the pediatric population. 90% of the cases occur before the age of 5¹.

 

About 2/3 of the patients present with distant metastases (orbital metastases occur in 10-20% of all cases of neuroblastoma) and 50% of neuroblastoma patients have a palpable abdominal mass. The most common orbital presentation of neuroblastoma is a rapidly expanding proptosis with eyelid ecchymoses².

b. What other eye signs may occur with this condition?

Ecchymoses of the eyelids (raccoon eyes) and/or subconjunctival haemorrhage with proptosis are the most common findings in patients with orbital neuroblastoma. These  may be mistaken for non-accidental injury. There are several possible mechanisms including stretching of the blood vessels from a rapidly expanding tumour causing vessel ruptures and thrombocytopaenia as a result of tumour infiltration of the bone marrow.

 

Horner syndrome may occur in the presence of cervical and thoracic neuroblastomas. Paraneoplastic syndrome in the form of opsoclonus and cerebellar ataxia has been reported in about 2% of patients with neuroblastoma².

This patient has stage IV neuroblastoma and is currently undergoing chemotherapy.

Reference:

1. Albert DM & Jacobiec FA. Principles and Practice of Ophthalmology. Clinical Ophthalmology: Chapter 245: Metastatic and Secondary Orbital Tumors. 2nd edition. W.B. Saunders Company.

2. Brodeur GM, Castleberry RP. Neuroblastoma. In: Pizzo PA, Poplack DG, eds. Principles and practice of pediatric oncology. 3d ed. Philadelphia: Lippincott-Raven, 1977:761-7.