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

Melanoma of the dog and cat: consensus and guidelines

Melanoma of the dog and cat poses a clinical challenge to veterinary practitioners across the globe. As knowledge evolves, so too do clinical practices. However, there remain uncertainties and controversies. There is value for the veterinary community at large in the generation of a contemporary wide-ranging guideline document. The aim of this project was therefore to assimilate the available published knowledge into a single accessible referenced resource and to provide expert clinical guidance to support professional colleagues as they navigate current melanoma challenges and controversies. Melanocytic tumors are common in dogs but rare in cats. The history and clinical signs relate to the anatomic site of the melanoma. Oral and subungual malignant melanomas are the most common malignant types in dogs. While many melanocytic tumors are heavily pigmented, making diagnosis relatively straightforward, melanin pigmentation is variable. A validated clinical stage scheme has been defined for canine oral melanoma. For all other locations and for feline melanoma, TNM-based staging applies. Certain histological characteristics have been shown to bear prognostic significance and can thus prove instructive in clinical decision making. Surgical resection using wide margins is currently the mainstay of therapy for the local control of melanomas, regardless of primary location. Radiotherapy forms an integral part of the management of canine oral melanomas, both as a primary and an adjuvant therapy. Adjuvant immunotherapy or chemotherapy is offered to patients at high risk of developing distant metastasis. Location is the major prognostic factor, although it is not completely predictive of local invasiveness and metastatic potential. There are no specific guidelines regarding referral considerations for dogs with melanoma, as this is likely based on a multitude of factors. The ultimate goal is to provide the best options for patients to extend quality of life and survival, either within the primary care or referral hospital setting.

Outcomes of Treatment of Eyelids and Third Eyelid Tumours in Dogs Using High-Frequency Radiowave Surgery

In human ophthalmology, the benefits of using high-frequency radiowave (HFR) electrocautery for surgical procedures were demonstrated and include effective haemostasis, shorter surgery times, and rapid recovery. In canine eyelid surgery, intraoperative bleeding is a common feature that may obscure the surgical field view and lead to the increased swelling of adjacent tissues, bruising, and pain. To evaluate the efficacy and benefits of HFR electrocautery in canine eyelid and third eyelid surgery, the medical records of 48 surgical excisions of eyelid tumours (involving up to one-third of the eyelid length) and 4 third eyelid excisions were reviewed. The information was collected including the breed, age, clinical signs, HFR power setting and mode of the surgical unit, electrode used for the surgery, intraoperative complications, histopathological diagnosis, and postoperative outcomes. Surgical techniques were performed using the Surgitron Dual 3.8 MHz Frequency RF device (Ellman International, Oceanside, NY, USA). Intraoperative bleeding was recorded as absent or very mild, and the surgical procedures were very fast. No complications occurred during the procedures. Healing within 10 days was observed in all the dogs. No tumour recurrences were recorded at the 12-month follow-up. HFR electrosurgery proved to be a safe, effective, and easy-to-perform technique for the removal of eyelid and third eyelid tumours in dogs.

Accuracy of data in abstracts of veterinary ophthalmology research articles published in peer-reviewed journals

OBJECTIVE

Assess the accuracy of abstracts in published veterinary ophthalmology articles.

PROCEDURES

Abstracts and contents of 204 original research articles in veterinary ophthalmology published in seven peer-reviewed journals between 2016-2020 were reviewed. Abstracts were considered inconsistent if they contained data that were either missing from or inconsistent with corresponding data in the article's body. Each abstract was graded between 0 (inaccurate) to 3 (accurate), and each inconsistency was subjectively classified as minor or major. The influence of selected variables was assessed: journal, impact factor, year of publication, number of words in abstract, study type (prospective/retrospective), and characteristics of the corresponding author [institution (academia/private practice), country of domicile (native/non-native English), number of publications].

RESULTS

Most abstracts were accurate, with 1%, 4%, 9% and 86% receiving a score of 0, 1, 2 and 3, respectively. When detected, most inconsistencies were considered minor (77%). Although not statistically significant (p ≥ .130), the proportion of articles with a perfect score (=3) was higher in prospective (88%) vs. retrospective (81%) studies, academia (88%) vs. private practice (78%), and studies from corresponding authors domiciled in English (89%) vs. non-English (83%) speaking countries. A significant but very weak (r = -0.15 to -0.19; p ≤ .034) negative correlation was found between accuracy score and number of words, as well as 1-year and 5-year impact factors.

CONCLUSIONS

Although relatively uncommon, data in abstracts that are inconsistent or missing from the article's body do occur in veterinary ophthalmology articles, and could adversely influence a reader's interpretation of study findings.

Diagnosing Corneal Pigmentation in Small Animals

The transparency of the cornea is critical to its role in transmitting light. Loss of corneal transparency results in visual impairment. Corneal pigmentation results from melanin accumulation in the epithelial cells of the cornea. Differential diagnosis for corneal pigmentation include corneal sequestrum, corneal foreign body, limbal melanocytoma, iris prolapse, and dermoid. These conditions must be excluded to reach a diagnosis of corneal pigmentation. A myriad of ocular surface conditions are associated with corneal pigmentation, including qualitative and quantitative tear film deficiency, adnexal disease, corneal ulceration, and breed-related corneal pigmentation syndromes. Accurate etiologic diagnosis is critical to determining effective treatment.

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.

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.