The aim of the study is to examine cases of oral squamous cell carcinoma in cats based on clinical and morphological data and analysis of current literature. Objectives: to systematize information on risk factors and molecular drivers of FOSCC; to substantiate algorithms for staging and locoregional monitoring of FOSCC; to characterize cytomorphological features of oral squamous cell carcinoma and regional lymph nodes in cats. A series of five clinical cases of FOSCC were analyzed in combination with a narrative review of the literature to characterize clinical, macro- and microscopic and cytological features, staging algorithms and treatment options with outcome assessment. All patients underwent clinical examination, imaging, bilateral fine-needle aspiration of mandibular lymph nodes and histological verification of the diagnosis using H&E stains (with decalcification when necessary). Main outcomes: overall survival (OS), mitotic index (MI), regional node status and the presence of bone invasion. Descriptive statistics, the Mann–Whitney test, Cliff's δ, and the Kaplan–Meier estimate were used. Ulcerative-infiltrative gingival lesions predominated. Significant bone invasion was detected in 80 % of cases (T4 according to the veterinary modification of TNM staging), while no bone invasion was detected in 20 % of cases (T3 according to the overall assessment). Keratinization in tumor complexes was absent or minimal (nonkeratinizing spectrum), which is consistent with the aggressive local course of this nosology in cats. Intercellular bridges and focal signs of desmoplasia were observed in all preparations. Mitotic activity ranged from 2 to 5 mitoses per 10 fields of view at standard magnification, with a median of 3/10 fields of view (Q1-Q3: 2–4), which corresponds to a low-moderate level of proliferation for squamous cell carcinomas in this location. The findings highlight the osteoinvasive nature of FOSCC, the clinically significant incidence of regional node involvement, and the need for standardized staging (bilateral node aspiration and chest imaging) with a multidisciplinary focus on local control and quality of life.
Dem'yancev et al. (Fri,) studied this question.