Histological Classification and Immunohistochemical Study of Feline Colorectal Epithelial Tumors

Abstract

Among 113 feline gastrointestinal epithelial tumors diagnosed between 2006 and 2019, 78 (69%) were detected in the colorectum. Fifty colorectal tumors were selected for further pathological evaluations, of which 9 (18%) were histopathologically diagnosed as adenomas and 41 (82%) as carcinoma. The carcinomas included 33 tubular adenocarcinomas (TAC), 5 tubulovillous adenocarcinomas (TVAC), 2 mucinous adenocarcinomas, and 1 undifferentiated carcinoma. Histopathologically, TAC frequently showed vascular invasion (17/33 cases, 52%). In TAC cases, serosal infiltration (13/15 cases, 87%) and lymph node metastasis (8/9 cases, 89%) were common in bowel resection and lymphadenectomy samples, respectively. Immunohistochemically, the tumor cells of most cases were positive for cytokeratin (CK) 20 (50/50 cases, 100%) and CDX2 (48/50 cases, 96%). Focal immunopositivity for CD10 (11/50 cases, 22%) and CK7 (15/50 cases, 30%) was observed irrespective of the histological subtype. Only a few cases showed diffuse nuclear accumulation of β-catenin (2/50 cases, 4%) and p53 (5/50 cases, 10%). A lack of tubule formation, female sex, and low CDX2 labeling were statistically associated with carcinoma compared to adenoma (ρ = 0.615, P < .001; ρ = 0.279, P = .050; and ρ = −0.265, P = .063, respectively). Other features, including mucin profiles, Ki67 labeling index, and accumulation of β-catenin and p53, were not associated with malignancy. A sequence analysis revealed KRAS mutations in 3/7 TAC cases. These results suggest that KRAS mutations—rather than excessive Wnt/β-catenin signaling and the inactivation of TP53—contribute to the tumorigenesis of feline colorectal carcinoma.

Bridging the Species Gap: Morphological and Molecular Comparison of Feline and Human Intestinal Carcinomas

“…Beta-catenin immunoreactivity, in terms of a nuclear translocation of β-catenin, was scored semiquantitatively: 0 (negative; <5% positive cells); 1 (5–25% positive cells); 2 (26–50% positive cells); and 3 (>50% positive cells) (modified score from Uneyama et al) [ 12 ] ( Figure 2 ).…”

“…Mutations, which stabilize the CTNNB1 gene encoding for β-catenin and thus activate the canonical WNT/β-catenin signaling pathway, play a pivotal role in the pathogenesis of human [ 20 , 21 ] and canine [ 22 ] intestinal cancer. Based on previous immunohistochemical findings of other authors, showing that dysregulated and nuclear translocated β-catenin was present in spontaneous feline intestinal carcinomas [ 12 ], we shed light on the mutational status of feline CTNNB1 by performing Sanger sequencing of feline CTNNB1 exon 2 for the first time.…”

“…Feline intestinal carcinomas are more prevalent than canine ones [ 11 ] and occur in both the large and small intestine. The available literature provides contradictory statements regarding the most commonly affected site in cats [ 8 , 9 , 11 , 12 , 13 , 14 ]. Feline intestinal carcinomas are more frequent in older animals with increasing risk starting from the age of seven [ 8 , 9 ] and either a breed predisposition of Siamese cats [ 9 , 11 , 13 ] or no breed predisposition [ 8 , 12 ] has been reported.…”

“…The available literature provides contradictory statements regarding the most commonly affected site in cats [ 8 , 9 , 11 , 12 , 13 , 14 ]. Feline intestinal carcinomas are more frequent in older animals with increasing risk starting from the age of seven [ 8 , 9 ] and either a breed predisposition of Siamese cats [ 9 , 11 , 13 ] or no breed predisposition [ 8 , 12 ] has been reported. Tumors metastasize frequently, rapidly, and most often within the peritoneum or to local lymph nodes, but also to distant sites (lung, liver, spleen) [ 8 , 11 , 13 , 15 ].…”

A Novel Approach to Supply the Water Reservoir Demand Based on a Hybrid Whale Optimization Algorithm

“…Multicriteria decision-making problems have been commonly solved in numerous fields using this technique. According to Yoon and Huang, the following algorithm is presented for TOPSIS [42]. e first stage is building R as the normalized decision matrix:…”