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OP2.7-8 | Orbital Tumours: Classification, Presentation, Workup and Referral — SDL Guide (Part 3)

Management of Orbital Tumours

Management decisions for orbital tumours are made at the intersection of tumour biology, tumour location, and the patient's visual status. There is no single treatment protocol that applies across all orbital tumours — a capillary haemangioma of infancy resolves without intervention (observation only), whereas a rhabdomyosarcoma requires emergency surgical biopsy followed by chemotherapy and radiotherapy within days. What unifies the management of all orbital tumours is a set of principles that must be applied regardless of the specific tumour type: protecting the cornea from exposure keratopathy while proptosis is present, and monitoring the optic nerve with colour vision testing at every review visit. Failure to apply these two universal principles results in preventable morbidity even when the definitive tumour treatment is correct.

Management of orbital tumours requires two universal principles applied across all tumour types, plus tumour-specific treatment protocols.

Universal principles:
1. Corneal protection at every stage: Any proptosis causing incomplete lid closure must be managed with preservative-free lubricants (daytime), ointment (night), and moisture chamber until the orbital mass is treated. A corneal ulcer from exposure keratopathy is preventable and represents a management failure.
2. Optic nerve monitoring: Colour vision and visual acuity at every review visit. Colour desaturation = emergency — do not wait for visual acuity to drop before acting.

Tumour-specific management:

Capillary haemangioma: If no functional threat (no amblyopia, no corneal exposure) — observation, as the majority involute by age 7–10 years. If vision-threatening (anisometropic amblyopia from large lesion, deprivation amblyopia from visual axis obstruction): oral propranolol 1–3 mg/kg/day is now first-line (β-blockade causes vasoconstriction + reduced VEGF in the haemangioma endothelium, producing rapid shrinkage). Alternative for superficial lesions: topical timolol gel. Surgery for residual or non-responding disease.

Dermoid cyst: Elective surgical excision before rupture occurs. If ruptured, urgent surgery to remove all cyst contents and initiate steroid treatment for the granulomatous inflammatory response.

Rhabdomyosarcoma: Oncological emergency. Treatment protocol: (1) Urgent biopsy under GA for histological diagnosis and IRS grouping; (2) Chemotherapy — VAC protocol (vincristine, actinomycin D, cyclophosphamide); (3) Radiotherapy for all but the most localised (Group I) disease. Orbital exenteration is NOT required — rhabdomyosarcoma is radiosensitive and chemo-sensitive. 5-year survival >90% for localised orbital disease.

Cavernous haemangioma: Observation is appropriate if proptosis is mild and vision is preserved. Intervention (surgical excision via lateral orbitotomy) is indicated for progressive proptosis, threatened vision, or unacceptable cosmetic deformity. The lesion's well-defined pseudocapsule facilitates complete excision. Stereotactic radiosurgery (Gamma Knife) is an alternative for surgically inaccessible lesions.

Optic nerve glioma: In children with stable vision — observation with serial MRI and visual field testing. Treatment if progressive: chemotherapy (carboplatin + vincristine for children under 5 years, where radiotherapy is avoided due to neurodevelopmental toxicity); radiotherapy for older children and adults with progressive disease. Surgical resection is rarely indicated and risks visual loss.

Lacrimal gland pleomorphic adenoma: Total en bloc excision with intact capsule via lateral orbitotomy. No biopsy before excision. Cure rate approaches 100% with clean margins. If capsule is breached at surgery, risk of recurrence and malignant transformation rises significantly.

Lacrimal gland adenoid cystic carcinoma: Surgery (orbital exenteration or globe-sparing resection depending on extent) + adjuvant radiotherapy. Prognosis is poor — 5-year survival approximately 21% — due to perineural spread to the cavernous sinus and skull base. Palliative chemotherapy may be offered for metastatic disease.

Orbital lymphoma: Low-grade MALT (isolated orbital): external beam radiotherapy (approximately 30 Gy) — 95%+ local control rate. Systemic B-cell lymphoma: combination chemotherapy with R-CHOP (rituximab + cyclophosphamide, doxorubicin, vincristine, prednisolone) ± orbital radiotherapy. Systemic staging mandatory before treatment allocation.

Orbital metastases: Palliative intent for most patients. Orbital radiotherapy for pain relief and visual preservation. Systemic oncological management per the primary tumour's protocol. Surgical debulking rarely indicated except for vision-threatening cases.

Indications for Referral and Red Flag Signs

Recognising the red flag features of orbital tumours and knowing the appropriate referral pathway is as important as knowing the management of each tumour individually. A delay in referral for a malignant orbital tumour can be the difference between cure and disseminated disease. Primary care physicians, general practitioners, and non-specialist ophthalmologists are frequently the first clinicians to see a patient with an orbital tumour, and the decision to refer urgently versus routinely determines the window for curative treatment. Rhabdomyosarcoma has a 10% mortality at five years when treated early; this rises sharply with delay. Adenoid cystic carcinoma of the lacrimal gland has a 50% mortality at ten years even with radical surgery; perineural spread and intracranial extension that develops during a delayed diagnosis makes resection impossible. Knowing the red flags allows the generalist to trigger the right pathway immediately.

Red flag signs requiring urgent (same-day or next-day) specialist referral:

1. Rapid onset proptosis in a child (days to weeks): Rhabdomyosarcoma until proved otherwise. Referral to a paediatric ophthalmologist and paediatric oncologist on the same day. CT orbit urgent.
2. Pain associated with an orbital mass: Points to malignancy (adenoid cystic carcinoma, metastasis), acute inflammation, or rhabdomyosarcoma. Pain in a lacrimal gland lesion = adenoid cystic carcinoma until proved otherwise.
3. Visual loss or colour desaturation in the context of proptosis: Compressive optic neuropathy — same-day emergency referral to orbital specialist. Do not send to outpatient clinic.
4. Afferent pupillary defect (RAPD) with proptosis: Indicates optic nerve compression or infiltration — emergency assessment required.
5. Bone erosion on CT: Indicates aggressive/malignant behaviour — urgent specialist review.
6. Bilateral periorbital bruising in a child ('panda eyes'): Neuroblastoma with orbital metastases — urgent paediatric oncology referral.
7. Rapid increase in the size of a known orbital lesion: Even a previously benign-appearing lesion that grows rapidly over weeks requires urgent review.

Referral pathways:

Clinical situation	Refer to
Rhabdomyosarcoma	Paediatric ophthalmologist + paediatric oncology (same day)
Orbital lymphoma	Medical oncology/haematology + ophthalmology
Orbital metastasis	Medical oncology + ophthalmology
Optic nerve glioma with progression	Neuro-ophthalmology + neuro-oncology
Optic nerve sheath meningioma	Neuro-ophthalmology + neurosurgery
Lacrimal gland tumour (any)	Orbital surgeon (oculoplastics)
Cavernous haemangioma with visual threat	Orbital surgeon

When observation is appropriate (no urgent referral):
- Small capillary haemangioma in infancy with no visual threat — paediatric ophthalmology monitoring.
- Dermoid cyst, stable, not at risk of rupture — elective surgical referral.
- Small cavernous haemangioma with normal vision — orbital specialist non-urgent review.

Self-Assessment

Review the following questions to consolidate your understanding of orbital tumours. These represent the level expected in NMC professional assessments and postgraduate viva examinations.

1. Enumerate the major causes of orbital tumours in children and classify them as benign or malignant.

2. A 45-year-old woman presents with a 2-year history of S-shaped ptosis, inferomedial proptosis, and a superolateral orbital mass. CT shows a well-defined mass with bony remodelling. A junior colleague proposes 'incisional biopsy for diagnosis'. Explain why this is contraindicated and what the correct management is.

3. What is the pathognomonic fundoscopic finding in optic nerve sheath meningioma, and what is its mechanism?

4. What CT finding distinguishes a benign slow-growing orbital tumour from a malignant one at the level of bone changes?

5. A 5-year-old boy presents with bilateral periorbital bruising. What orbital tumour diagnosis must be excluded immediately, and from where does it arise?

Answers:

1. Childhood orbital tumours:
- Benign: Capillary haemangioma (infancy), dermoid cyst (suture lines), optic nerve glioma (pilocytic astrocytoma — benign histologically), lymphangioma, orbital varix.
- Malignant: Rhabdomyosarcoma (commonest primary orbital malignancy in children), neuroblastoma metastasis (adrenal primary), optic nerve sheath involvement by intracranial malignancy.

2. Incisional biopsy of a suspected lacrimal gland pleomorphic adenoma is contraindicated because it seeds tumour cells along the biopsy track and within the orbit, converting a fully curable disease (100% cure rate with en bloc excision) into a locally recurrent and eventually malignant lesion (carcinoma ex pleomorphic adenoma). The correct management is total en bloc excision through a lateral orbitotomy, without capsule disruption.

3. Optociliary shunt vessels (also called retinociliary collateral veins) — abnormal vessels visible at the disc margin connecting the retinal venous circulation to the ciliary/choroidal venous system. They develop in response to chronic obstruction of the central retinal vein by the surrounding meningioma, providing collateral venous drainage. They are pathognomonic of chronic optic nerve sheath compression.

4. Bony remodelling (smooth expansion of the bony orbit with preservation of cortical integrity) = benign slow-growing tumour (cavernous haemangioma, mucocele, pleomorphic adenoma). Bony erosion (cortical destruction, irregular moth-eaten appearance) = malignant tumour (rhabdomyosarcoma, adenoid cystic carcinoma, metastasis).

5. Neuroblastoma with orbital metastases — the bilateral periorbital bruising ('panda eyes' or 'raccoon eyes') is caused by haemorrhagic metastases in the orbital walls and periorbita. Neuroblastoma arises from the adrenal medulla (or, less commonly, other sympathetic ganglia). Immediate paediatric oncology referral is required.