Penetrating sclerokeratoplasty and autologous pinnal cartilage and conjunctival grafting to treat a large limbal melanoma in a dog

Current Therapeutics and Future Perspectives to Ocular Melanocytic Neoplasms in Dogs and Cats

Neoplasms of melanocytic origin are diseases relevant to dogs and cats' ophthalmic oncology due to their incidence, potential visual loss, and consequent decrease in life quality and expectancy. Despite its non-specific clinical presentation, melanocytic neoplasms can be histologically distinguished in melanocytomas, which present benign characteristics, and malignant melanomas. The diagnosis often occurs in advanced cases, limiting the therapeutic options. Surgery, cryotherapy, radiotherapy, photodynamic therapy (PDT), and laser are currently available therapeutic strategies. As no clinical guidelines are available, the treatment choice is primarily based on the clinician's preference, proficiency, and the owner's financial constraints. While surgery is curative in benign lesions, ocular melanomas present a variable response to treatments, besides the potential of tumour recurrences or metastatic disease. This review presents the currently available therapies for ocular melanocytic neoplasms in dogs and cats, describing the therapeutic, indications, and limitations. Additionally, new therapeutics being developed are presented and discussed, as they can improve the current treatment options.

Evaluation of eye melanoma treatments in rabbits: A systematic review

Melanomas are the most common cancer of the eye in canines, felines and humans. The treatment approaches vary, since no gold standard exists. Therefore, this systematic review aimed to compare the treatment modalities in ocular melanoma in rabbits. Medline/PubMed, Cochrane Library, Web of Science and Embase were searched for articles published until 21 April 2021 in English, Portuguese or Spanish, reporting animal studies evaluating photodynamic therapy (PDT), laser, radiotherapy or surgical excision. Twenty-seven articles were included for the qualitative synthesis, with publication dates from 1970 to 2018. Of the selected studies, 19 used PDT, six used radiotherapy and two used laser as treatment. No studies regarding surgical therapy that met the inclusion criteria were obtained. The tumour therapy results were evaluated in a heterogeneous manner for different periods and various methods, including microscopy, angiographic, histological examination, fundoscopy, ultrasound exam and electroretinogram. The treatment modalities analysed successfully treated the ocular melanoma, with tumour necrosis being commonly observed. Despite the therapeutic efficacy shown, side effects have been reported for all the therapies. The studies showed high heterogeneity, and therefore, in the future, new studies should be carried out to increase knowledge about ocular melanoma treatment. The analysed therapies can be used successfully in the treatment of ocular melanoma, with more conservative options such as PDT presenting great potential.

Deep lamellar keratectomy and penetrating scleroplasty using CO2 laser photoablation and bimodal grafting for the treatment of a limbal melanoma in a dog

A novel approach for en bloc resection of a limbal melanoma using a CO2 laser in a dog. Benefits of this advanced technique include excellent surgical precision, improved hemostasis, and the induction of coagulative necrosis of neoplastic cells.

The combined use of surgical debulking and diode laser photocoagulation for limbal melanoma treatment: a retrospective study of 21 dogs

OBJECTIVE

To evaluate effectiveness and safety of debulking and diode laser photocoagulation (DPC) for the treatment of limbal melanoma (LM).

PROCEDURE

Retrospective multi-institutional case series. Medical records of animals diagnosed with LM at the Centro Veterinario Specialistico (CVS) and at the Long Island Veterinary Specialists from 1994 to 2014 were retrieved. Signalment, location, extent of tumors, recurrence rate, and early and late complications were reported. Patient follow-up information was obtained from veterinary ophthalmologists, primary care veterinarians, and where appropriate, owners.

RESULTS

Twenty-one eyes of 21 dogs (13 females and 8 males) were included in this study. The dogs' average age was 6 years (range: 7 months-11 years). The follow-up period ranged from 1-108 months (median 48 months) after the last DPC procedure. Long-term follow-up was obtained by telephone interviews in 6 of 20 cases and by clinical re-evaluations in 14 of 20 cases. The most common early complications were a moderate anterior uveitis and peripheral corneal edema (21/21 eyes). Late complications included corneal fibrosis and/or pigmentation (20/21). In one case, a severe bullous keratopathy associated with extensive corneal fibrosis was observed (1/21). One case was blind due to concurrent Sudden Acquired Retinal Degeneration (SARD). However, after surgery 2 of 20 eyes lost vision and one of these was enucleated.

CONCLUSIONS

Debulking, in addition to diode laser photocoagulation, was technically straightforward to perform, minimally invasive, well tolerated, and highly successful in this case series.