Marginal resection and infracyanine green‐mediated photodynamic therapy in the management of feline eyelid squamous cell carcinoma: Two cases

Abstract

ObjectiveDescribe the presenting features, surgical procedure, and clinical outcomes of two cats managed with marginal resection and photodynamic therapy (PDT) for eyelid squamous cell carcinoma (SCC).Animals StudiedA 12‐year‐old female spayed domestic shorthair cat (case 1) and a 10‐year‐old female spayed domestic shorthair cat (case 2).ProceduresFollowing marginal resection of the eyelid neoplasm, hemostasis was achieved using a handheld cautery unit then 1 mL of infracyanine green was injected into the surgical wound bed. Photodynamic therapy was performed using an 810 nm diode laser in two consecutive steps: (i) six cycles at 500 mW for 30 s per cycle, using a rapid movement; then (ii) one (case 1) or two cycles (case 2) of 30 s at 2000 mW, using a slow deliberate movement to effect (charred surface).ResultsHistopathology was consistent with SCC resected with incomplete margins in both cats. Follow‐up duration was 416 and 161 days in case 1 and case 2, respectively. Consecutive exams and photo‐documentation (in clinic or by owners) showed appropriate healing of the lower eyelid, with a smooth lid margin, and no evidence of tumor regrowth or ocular irritation. Subtle trichiasis was noted in case 1 on day 185, but not at the last follow‐up.Conclusions and Clinical RelevanceMarginal resection followed by PDT may be a valid alternative to complete surgical resection of periocular SCC in cats. The procedure was easy to perform, post‐operative recovery was uncomplicated, and neither cat developed recurrent disease during the follow‐up period.