Topical mitomycin C for the treatment of conjunctival and corneal epithelial dysplasia and neoplasia

Local chemotherapeutic agents for the treatment of ocular malignancies

We critically analyze available peer-reviewed literature, including clinical trials and case reports, on local ocular cancer treatments. Recent innovations in many areas of ocular oncology have introduced promising new therapies, but, for the most part, the optimal treatment of ocular malignancies remains elusive.

Topical interferon or surgical excision for the management of primary ocular surface squamous neoplasia

OBJECTIVE

To describe the successful treatment and long-term outcomes of primary ocular surface squamous neoplasia (OSSN) with topical interferon alfa-2b or surgical excision.

DESIGN

Retrospective, comparative, interventional case series.

PARTICIPANTS

Twenty-nine consecutive patients with OSSN never before treated.

INTERVENTION

Patients with primary OSSN chose topical interferon alfa-2b or excision with wide surgical margins, with crossover to surgery in those interferon-treated patients whose OSSN failed to regress within 2 months after beginning therapy.

MAIN OUTCOME MEASURES

Successful resolution of clinical disease at 2 months after topical interferon treatment and time to recurrence after either topical interferon or surgical excision.

RESULTS

Of 29 patients with primary OSSN, 15 elected topical interferon and 14 chose surgical excision. Two patients in the interferon group subsequently underwent surgical excision for apparent lack of response to interferon. No patient in either group developed a recurrence during the study period (disease-free follow-up: interferon group, mean, 35.6 months [95% confidence interval, 21.9-49.3]; surgery group, mean, 35.6 months [22.9-48.3]).

CONCLUSIONS

Both topical interferon alfa-2b and aggressive surgical excision appear to be effective for primary OSSN.

Randomized Controlled Trial of Topical Mitomycin C for Ocular Surface Squamous Neoplasia

OBJECTIVE

To assess the efficacy and safety of mitomycin C in the treatment of ocular surface squamous neoplasia.

DESIGN

Prospective, randomized, controlled, masked, single-center trial.

PARTICIPANTS

Forty-eight consecutive patients with biopsy-proven noninvasive ocular surface squamous neoplasia.

INTERVENTION

Mitomycin C (0.4 mg/ml) or a placebo was administered as 1 drop 4 times a day for 3 weeks, with crossover of drops if there was no regression within 6 weeks.

MAIN OUTCOME MEASURES

Successful treatment was measured as complete resolution of the neoplasia by slit-lamp examination within 6 to 8 weeks of treatment, with a secondary end point of histological resolution by 6 weeks.

RESULTS

None of 20 in the placebo group resolved clinically, whereas 24 of 26 in the mitomycin group resolved, giving a relative resolution rate of mitomycin versus placebo of 40.87 (95% confidence interval [CI], 1.01-1656.8). There were no complications. There was no statistical treatment effect on histological resolution, with a resolution rate of mitomycin versus placebo of 1.37 (95% CI, 0.34-5.42).

CONCLUSIONS

Mitomycin C (0.4 mg/ml) eyedrops used 4 times a day for 3 weeks is an effective agent to cause early clinical resolution of noninvasive ocular surface squamous neoplasia.

Topical mitomycin-C for pagetoid invasion of the conjunctiva by eyelid sebaceous gland carcinoma

PURPOSE

To evaluate the efficacy of topical mitomycin-C for pagetoid invasion of the conjunctiva by sebaceous gland carcinoma.

DESIGN

Prospective noncomparative consecutive interventional case series.

INTERVENTION

All patients received topical 0.04% mitomycin-C four times daily for 1 week followed by 1 week off medication. The treatment cycles were repeated until resolution of the conjunctival malignancy was clinically evident.

PARTICIPANTS

Four patients with histopathologically proven intraepithelial (pagetoid) invasion of the conjunctiva by sebaceous gland carcinoma were managed with this regimen.

RESULTS

The mean patient age was 78 years. Before treatment, the main tumor site included the upper eyelid in two cases and the lower eyelid in two cases. Previous resection of the tumor had been performed elsewhere in three cases over the prior 6 years. At the time of our examination, map biopsies confirmed pagetoid invasion involving 25% to 90% of the conjunctival surface, with bulbar, forniceal, and tarsal conjunctival involvement in all four cases and corneal extension in one case. There was no evidence of deep tumor within the conjunctival stroma or tarsus in any case. After treatment, medication intolerance and early discontinuation occurred in one patient, and continued tumor progression was documented. Of the remaining three patients, chemotherapy was used for a mean of four cycles with complete resolution of the pagetoid invasion, confirmed histopathologically in two cases, and without recurrence in all three cases over 12 months (mean) follow-up. The medication caused moderate temporary local irritation but no serious intraocular or extraocular complications.

CONCLUSIONS

Preliminary evidence suggests that topical mitomycin-C is effective treatment for pagetoid invasion of the conjunctiva by sebaceous gland carcinoma. Longer follow-up is necessary to assess the duration of tumor control.

Effects of topical mitomycin on inner ear: a light and electron microscopic study

Providing maintenance of myringotomy patency without use of ventilation tubes in the treatment of secretory otitis media has been one of the important study areas. For this reason, laser and Mitomycin C (MMC) are used together in experimental studies. But there has been no ultrastructural studies concerning whether leakage of MMC to middle ear during application of this procedure has an ototoxic effect or not and if so, to what extent. In this study, we searched the ultrastructural changes which occurred in the middle ear by direct applications of MMC to the middle ear for different time durations. The study was carried out over thirty adult guinea pigs without ear diseases. Bilateral myringotomy was performed and MMC was applied only to the right middle ear of each guinea pig. The first group received MMC once for 10 minutes, the second group received it once for 20 minutes, and the third group took it each day for 10 minutes during a one week period. The left ears of the samples were accepted as the control group. On the 8th day, sacrification was carried out. After electron and light microscopy examination, significant changes in the inner ear were observed in the third group though no significant change was observed for the first and the second groups. As a result it was concluded that the application of MMC to the middle ear once for a short duration causes no toxic effect on the inner ear.

Topical mitomycin C for extensive, recurrent conjunctival-corneal squamous cell carcinoma

PURPOSE

To evaluate the efficacy of topical mitomycin C for extensive recurrent conjunctival and corneal squamous cell carcinoma (SCC).

DESIGN

Interventional case series.

METHODS

A prospective study was conducted in a single institution. Ten patients (ten eyes) with extensive recurrent conjunctival and corneal SCC were studied. The patients received topical mitomycin C 0.04% one drop four times daily in the eye with SCC. Treatment cycles were defined as 1 week using medication followed by 1 week without medication. Such treatment cycles were repeated until resolution of the conjunctival malignancy was clinically evident. The main outcome measures were tumor response and medication-related complications.

RESULTS

Of the ten patients, the median age was 66 years (range 33-77 years). Before referral, the patients had undergone a median of two previous conjunctival tumor resections revealing the diagnosis of in situ SCC in three cases and locally invasive SCC in six cases. At presentation, the tumor involved the limbus and cornea in all ten eyes, forniceal conjunctiva in three eyes, and tarsal conjunctiva in one eye. The extensive tumor affected a median of 10 clock hours of limbal conjunctiva and 10 clock hours of cornea, with corneal epithelial invasion for a median of 50% (range 20%-100%) of its surface. Mitomycin C 0.04% four times daily was applied for a median of three cycles (range 1-4 cycles). Complete tumor regression was documented in all ten cases (100%). There was no recurrence over a mean follow up of 22 months (range 6-50 months). Mitomycin C caused moderate temporary local irritation and conjunctival erythema and chemosis, but no long-term intraocular or extraocular complications.

CONCLUSIONS

Based on this small series, topical mitomycin C 0.04% appears to be a safe and effective therapy for conjunctival or corneal SCC, even when there is extensive recurrent tumor.