Sir,

Neuroblastoma is a rare malignant tumour of neural crest cells, which can metastasize to the orbit and present as proptosis and periorbital ecchymosis (‘raccoon eyes’). This is deemed stage 4 disease.1 It is associated with an unfavourable prognosis, and management of this stage is with chemotherapy (followed by local excision and radiotherapy of the primary). Chemotherapy constitutes an induction phase followed by myeloablative conditioning with haematopoietic stem cell reconstitution and treatment for minimal residual disease.2 The diagnosis of orbital cellulitis in these patients may be difficult to establish, in the setting of pre-existing proptosis from the metastasis and febrile neutropenia from immunosuppression. Such a case is presented here.

Case report

A 4-year-old girl was referred with headaches, right subconjunctival haemorrhage, and proptosis. An immediate CT scan revealed a right superolateral orbital mass (Figure 1a). A biopsy of the orbital mass by an ophthalmic surgeon confirmed neuroblastoma. The primary lesion was localized to the left adrenal gland with abdominal ultrasound and CT. Eighty days of the neuroblastoma high-risk 1 protocol comprising IV vincristine, carboplatin, and etoposide was commenced. During chemotherapy, recurrent episodes of febrile neutropenia developed. During an episode of febrile neutropenia she was noted to have deteriorating proptosis and development of periorbital erythema on day 70 of chemotherapy. The doubt was whether this represented treatment failure with deterioration of the orbital tumour or an orbital infection. A CT scan revealed a right pansinusitis, and right medial rectus enlargement indicating extension into the extraconal compartment. The original orbital mass showed no radiological deterioration and orbital cellulitis was deemed by the probable pathology. She was placed on intravenous teicoplanin, meropenem, and amphoterocin. A sinus washout was performed, which revealed a fungus. Thoracic CT demonstrated multiple areas of lung consolidation. Lung biopsy confirmed the organism to be Aspergillus flavus. Voricanozole was added to maximize antifungal therapy. Intravenous metronidazole and ciprofloxacin were added for concurrent urinary infection. A week later the preseptal inflammation improved but visual acuity decreased to light perception only and an RAPD developed. An urgent CT showed the right medial rectus compressing the optic nerve (Figure 1b). Urgent antral washout with ethmoidectomy and medial wall decompression was performed (Figure 1c). Within days there was marked systemic improvement, reduction of the proptosis and preseptal inflammation. The visual acuity stabilized at 2/60 with a residual pale optic disc secondary to optic nerve compression.

Figure 1
figure 1

(a) the right lateral orbital tumour; (b) the right medial rectus compressing the optic nerve; (c) the appearance following orbital decompression and completion of chemotherapy.

Full size image

Comment

The clinical dilemma here was to ascertain treatment failure or orbital cellulitis, as the symptoms and signs of orbital cellulitis in this situation became of questionable value. The normal signs of orbital cellulitis are fever, proptosis, and periorbital erythema. All of these signs could be attributed to the primary disease or to the complications of treatment. A CT scan was invaluable as it demonstrated pansinusitis and extraconal orbital involvement with no unfavourable change in characteristics of the original tumour.

Between 10 and 20% of cases3 of neuroblastoma have orbital involvement all of whom undergo chemotherapy. As orbital neuroblastoma and orbital cellulitis have very similar features during chemotherapy, a high index of suspicion is imperative in order not to miss a diagnosis of orbital cellulitis in this situation. Russo et al4 have reported a case of orbital cellulitis in a patient with neuroblastoma without orbital metastasis. To the best of our knowledge, no presentation of orbital cellulitis in a case of metastatic orbital neuroblastoma has been hitherto reported.