96th DOG Annual Meeting, 1998


Postoperative treatment of malignant melanoma of the conjunctiva with Mitomycin C eye drops under cytological and cytometrical control

A. Kersten1, R. Sundmacher1, B. Nadjari2, A. Böcking2

Background: Malignant melanomas of the conjunctiva (MM) which arise from primary acquired melanosis (PAM) have a specially high rate of recurrences. Postoperative radiation is of equivocal efficiency, and therapeutic alternatives are therefore urgently needed. Our aim was to investigate the efficiency and safety of postoperative chemotherapy with mitomycin C eye drops (MMC) under cytological and DNA-cytometrical control.

Methods: Conjunctival smears were examined cytologically and DNA- cytometrically. Its results were correlated to histology following excision. Over 6 cycles of 1 week MMC eye drops 0,04% 4 times daily were given. We performed cytological and DNA-cytometrical controls monthly.

Results: In 2 of 5 eyes PAM-MM was the primary diagnosis and in 3 of 5 eyes we had to treat recurrences after multiple surgery plus full radiation. In 3 eyes (1 primary, 2 recurrences) therapy with MMC was up to now successful (follow-up 7,9 month). Pigmentation disappeared and cytologically no suspicious cells were seen. 2 eyes exhibited recurrences confirmed by cytology. DNA-cytometry showed an aneuploidy respectively an euploidic polyploidy. In the latter case the melanoma cells could unequivocally be marked by melanoma-specific- HMB45-antibodies.

Conclusions: Cytology and DNA-cytometry, with the addition of HMB45 antibody staining if necessary, are safe noninvasive proceedings to control the efficiency topical cytostatic therapy of malignant melanomas. Our current experiences indicate that Mitomycin C may be a promising topical chemotherapeutical agent for alternative or additive therapy and prophylaxis of conjunctival melanomas, especially PAM- melanomas.

1 Eye Hospital, 2 Institute of Cytopathology, Heinrich-Heine-University, Moorenstrasse 5, 40225 Duesseldorf