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Updated: Apr 27, 2026
Author Spotlight: Anterior HR-OCT as a Non-Invasive Tool for Characterizing Ocular Surface Squamous Neoplasia
Published on: August 9, 2024
Management of diffuse ocular surface squamous neoplasia: efficacy and complications of topical chemotherapy
Adam K Rudkin1, Lucy Dempster, James S Muecke
1South Australian Institute of Ophthalmology, Adelaide, South Australia, Australia; Discipline of Ophthalmology & Visual Sciences, University of Adelaide, North Terrace, South Australia, Australia.
Background:
Ocular surface squamous neoplasia (OSSN) characterized by diffuse conjunctival or corneal spread is much less common than localized conjunctival disease. However, it is an important subcategory of the disease because of the difficulty it poses to treatment. It is rarely amenable to simple excision, and a purely surgical approach usually necessitates ocular surface reconstruction. Primary treatment with topical chemotherapy is an alternative, but its efficacy for these lesions is not well understood.
Design:
Retrospective case series.
Participants:
Thirty-eight eyes treated for diffuse OSSN, defined as a lesion extending over five or more limbal clock hours or by extensive central or paracentral corneal spread.
Methods:
Treatment utilized either topical 5-FU 1% or mitomycin-C (MMC) 0.04%.
Main Outcome Measures:
(i) Disease remission; (ii) complications.
Results:
Thirty-two patients were treated for a primary diffuse OSSN. Ten patients (31%) required further treatment for disease persistence or recurrence. Thirteen patients had previously undergone a single unsuccessful treatment course for diffuse OSSN. Administration of a second treatment course (whether MMC or 5FU) was successful in 46% (six) of patients. 5-FU 1% resulted in drug-related complications in seven of 12 cases, and included a single case of focal paracentral corneal stromal melt. MMC 0.04% resulted in transient drug related complications in 23 of 39 cases.
Conclusion:
Diffuse OSSN is often recalcitrant to initial treatment with either 5-FU 1% or MMC 0.04%, and a pragmatic and vigilant approach to this heterogenous disease is required. Compared to localized disease, diffuse disease often requires multiple treatment efforts.
Insights
Diffuse ocular surface squamous neoplasia (OSSN) often requires multiple treatments. Topical chemotherapy with 5-FU 1% or mitomycin-C (MMC) 0.04% can be effective but may lead to complications and recurrence.
Area of Science:
- Ophthalmology
- Oncology
Background:
- Diffuse ocular surface squamous neoplasia (OSSN) is a rare but challenging subcategory of OSSN.
- Unlike localized disease, diffuse OSSN requires complex treatment strategies, often involving ocular surface reconstruction.
- The efficacy of topical chemotherapy for diffuse OSSN remains incompletely understood.
Purpose of the Study:
- To evaluate the efficacy and complications of topical 5-fluorouracil (5-FU) 1% and mitomycin-C (MMC) 0.04% for treating diffuse ocular surface squamous neoplasia (OSSN).
- To assess the need for repeat treatment courses in patients with diffuse OSSN.
Main Methods:
- Retrospective case series of 38 eyes with diffuse OSSN.
- Diffuse OSSN defined by lesions spanning ≥5 limbal clock hours or extensive corneal involvement.
- Treatment involved topical 5-FU 1% or MMC 0.04%.
Main Results:
- 31% of primary diffuse OSSN cases required further treatment.
- 46% of patients receiving a second treatment course achieved remission.
- 5-FU 1% caused complications in 58% of cases, including corneal melt; MMC 0.04% caused transient complications in 59% of cases.
Conclusions:
- Diffuse OSSN is frequently resistant to initial topical chemotherapy with 5-FU 1% or MMC 0.04%.
- Multiple treatment interventions are often necessary for diffuse OSSN.
- A pragmatic and vigilant approach is essential for managing this heterogeneous condition.
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