Ocular Oncology Surgeries

Intro to Ocular Oncology Surgery - Setting the Stage

• Focuses on surgical treatment of tumors affecting the eye, orbit, and adnexa.
• Primary Aims:
  • Life salvage (critical for malignant tumors).
  • Globe preservation.
  • Vision retention/restoration.
  • Acceptable cosmesis.
• Key Surgical Modalities: Biopsy, local excision, enucleation, exenteration, and reconstructive techniques.

⭐ Histopathological examination of excised tissue is crucial for diagnosis, staging, and guiding further treatment in ocular oncology.

Anterior Segment Tumor Surgeries - Surface & Lid Lesions

• Principles: Complete tumor excision with histologically clear margins; prioritize globe salvage, visual function, and cosmesis.
• Common Procedures:
  • Eyelid Lesions: Excisional biopsy (small/benign), Mohs Micrographic Surgery (MMS) for BCC/SCC (margin control), cryotherapy (e.g., trichiasis with tumor), complex reconstruction (flaps like Hughes, Cutler-Beard; grafts).
  • Ocular Surface Squamous Neoplasia (OSSN): Excisional biopsy ("no-touch" technique), adjunctive cryotherapy, topical chemotherapy (Mitomycin C, 5-Fluorouracil, Interferon α2b).

⭐ Mohs micrographic surgery (MMS) is gold standard for eyelid BCC, offering maximal tissue conservation and lowest recurrence rates (typically < 1-2% at 5 years).

Intraocular Tumor Surgeries: Uveal Melanoma - Dark Threats Within

Uveal melanoma: most common primary intraocular malignancy in adults. Goals: preserve vision, eye, prevent metastasis.

• Diagnosis: Ophthalmoscopy, USG (B-scan: acoustically hollow, choroidal excavation, collar-stud configuration), MRI.
• Treatment Modalities:
  • Radiotherapy: Brachytherapy (I-125, Ru-106 plaques), Proton Beam Therapy.
  • Local Resection: Transscleral iridocyclectomy, choroidectomy.
  • Enucleation: For large tumors (>10 mm apical height, >16 mm basal diameter), optic nerve invasion, painful blind eye.
  • Exenteration: Orbital extension.

⭐ The Collaborative Ocular Melanoma Study (COMS) showed no significant survival difference between I-125 brachytherapy versus enucleation for medium-sized melanomas.

Intraocular Tumor Surgeries: Retinoblastoma - Saving Sight & Life

• Goal: Primary aims are life preservation, then globe salvage, and finally vision retention.
• Key Surgical Options:
  • Enucleation: Standard for advanced intraocular disease (e.g., ICRB Group D/E, neovascular glaucoma, optic nerve invasion).
    • Orbital implant placed post-enucleation for cosmesis.
  • Globe-Salvage Therapies (for less advanced tumors):
    • Plaque Brachytherapy (Radioactive Iodine-125/Ruthenium-106): For selected solitary/multiple tumors.
    • Transpupillary Thermotherapy (TTT): Diode laser for small, posterior tumors; often adjuvant.
    • Cryotherapy: Double freeze-thaw for small, peripheral anterior tumors.
• Combined Modality Approach: Surgery often integrated with chemotherapy (systemic, intra-arterial, intravitreal).

⭐ Retinoblastoma is caused by mutations in the RB1 tumor suppressor gene on chromosome 13q14.

Orbital Tumor Surgeries & Exenteration - Deep Dive & Drastic Steps

• Orbital Tumor Surgery: Tailored for diagnosis & treatment.
  • Approaches: Anterior, Lateral (Kronlein), Transconjunctival, Transcranial, Endoscopic. Choice based on tumor location, size, depth.
  • Goals: Biopsy (incisional/excisional), cytoreduction (debulking), or complete tumor excision. Aim: preserve vision & globe.
• Exenteration: Radical removal of orbital contents, including globe.
  • Indications: Life-threatening malignancies (invasive SCC, melanoma, rhabdomyosarcoma) with diffuse orbital spread; aggressive fungal infections (mucormycosis).
  • Types: Total (all contents, periorbita, eyelids), Subtotal/Lid-sparing (eyelids preserved if uninvolved), Extended (involves adjacent sinuses/bone).
  • Reconstruction: Often delayed; granulation, skin grafts, local/regional flaps.

⭐ Exenteration: disfiguring, life-saving; for extensive malignancy or uncontrollable infection when globe salvage is impossible/unsafe.

High‑Yield Points - ⚡ Biggest Takeaways

• Retinoblastoma: Enucleation for large tumors; chemoreduction + focal therapy for smaller ones.
• Uveal Melanoma: Plaque brachytherapy for globe salvage; enucleation for large/extensive tumors.
• Conjunctival Melanoma: Wide excisional biopsy with cryotherapy; adjuvant topical chemotherapy (e.g., Mitomycin C).
• Conjunctival/Corneal SCC: Excisional biopsy ("no-touch"), cryotherapy; topical interferon alpha-2b is key.
• Eyelid Tumors (BCC/SCC): Mohs surgery for best cure & tissue preservation.
• Orbital Tumors: Orbitotomy approach varies by location; biopsy essential for diagnosis.