Study sharpens picture of ocular metastasis from feline lung cancer

A new retrospective case series in Veterinary Pathology helps fill in a diagnostic blind spot for feline ocular oncology: how intraocular metastatic carcinomas of presumed pulmonary origin look under the microscope, and how often they show supportive immunohistochemical features. Investigators reviewed 11 feline ocular biopsy cases submitted to the Comparative Ocular Pathology Laboratory of Wisconsin between 2019 and 2025 from cats with intraocular metastatic carcinoma and a history of a pulmonary mass. In the earlier conference abstract describing much of this cohort, the most common clinical presentations were uveitis, glaucoma, and an ocular mass; most tumors involved the uvea, especially the anterior uvea, and many showed “carpeting” growth along ocular structures. Alcian blue identified goblet cells in some cases, while thyroid transcription factor-1, or TTF-1, was positive in only a minority, underscoring that presumed pulmonary origin may still be difficult to confirm on IHC alone. (acvp.org)

Why it matters: For veterinary professionals, the paper adds practical morphologic detail to a rare but clinically important manifestation of feline pulmonary carcinoma. Prior literature has shown that pulmonary carcinoma is among the most common non-lymphoid metastatic tumors affecting feline eyes, and ocular signs can be an initial clue to otherwise occult systemic disease. The case series also reinforces the poor outlook once ocular metastasis is identified: in the conference abstract version, average survival after enucleation was 34 days. (pubmed.ncbi.nlm.nih.gov)

What to watch: Watch for how pathologists and ophthalmologists incorporate the paper’s histologic and IHC patterns into differentials for feline uveitis, glaucoma, and intraocular masses, especially when thoracic imaging shows even a presumptive lung lesion. (acvp.org)