Primary nonlymphoid gastrointestinal neoplasms in dogs in Rio Grande do Sul

Slaviero, Mônica; Argenta, Fernando F.; Ehlers, Luiza P.; Lorenzo, Cíntia De; Pavarini, Saulo P.; Driemeier, David; Sonne, Luciana

doi:10.1590/1678-5150-PVB-6408

ABSTRACT:

Gastrointestinal neoplasms (GIN) are uncommon in dogs, but they mainly show malignant behavior and poor prognosis. The types of GIN in dogs and their frequency, as well as their epidemiological and histopathological characteristics were analyzed through a retrospective study of biopsies from 24.711 dogs from 2005 to 2017. Additionally, histological sections of neoplasms were subjected to immunohistochemistry (IHC) using antibodies against pancytokeratin, vimentin, smooth muscle actin, c-Kit, S-100, CD31, CD79αcy, and neuron-specific enolase. Of the total samples from dogs analyzed, 88 corresponded to GIN. Neoplasms occurred more frequently in purebred dogs (64.8%, 57/88), males (53.4%, 47/88), with a median age of 10 years. The intestine was affected by 84.1% (74/88) of the cases. Of these, the large intestine was the most affected (67.6%, 50/74). Most of the neoplasms had malignant behavior (88.6%, 78/88). Regarding the classification of neoplasms, 46.6% (41/88) of the diagnoses corresponded to epithelial, 46.6% (41/88) were mesenchymal, 5.7% (5/88) were hematopoietic, and 1.1% (1/88) was neuroendocrine. The most frequently diagnosed neoplasms were papillary adenocarcinoma (19.3%, 17/88), leiomyosarcoma (17.0%, 15/88), gastrointestinal stromal tumors (GISTs) (12.5%, 11/88), and leiomyoma (5.0%, 8/88). Adenocarcinomas were located mainly in the rectum, whereas leiomyosarcomas and GISTs developed mainly in the cecum. Epithelial neoplasms showed a greater potential for lymphatic invasion whereas mesenchymal neoplasms appeared to be more expansive with intratumoral necrosis and hemorrhage. Immunohistochemistry was found to be an important diagnostic technique for the identification of infiltrating cells in carcinomas and an indispensable technique for the definitive diagnosis of sarcomas.

INDEX TERMS:
Primary nonlymphoid; gastrointestinal neoplasms; dogs; Rio Grande do Sul; Brazil; canine; gastric neoplasm; intestinal neoplasm; histopathology; immunohistochemistry

[1] *Corresponding author: lusonne@yahoo.com.br

Antibody/code	Clone	Antigenic recovery	Diluition	Detection system	Chromogen
Alpha smooth muscle actin^a (M0851)	Monoclonal (1A4)	20 min/120^oC, plus Tris-EDTA pH 9.0	1:50	MACH4^b	AEC^a
CD31^a (A0082)	Monoclonal (JC70A)	3 min/125^oC, plus citrate, pH 6.0	1:800	MACH4^b	AEC^a
CD79αcy^a (M7051)	Monoclonal (HM57)	20 min/96^oC, plus Tris-EDTA pH 9.0	1:50	MACH4^b	AEC^a
CD117 (c-Kit)^a (A04502)	Polyclonal	40 min/96^oC, plus citrate pH 6.0	1:300	MACH4^b	AEC^a
Neuron-Specific Enolase^a (M0873)	Monoclonal (BBS/NC/VI-H14))	40 min/96^oC, plus citrate, pH 6.0	1:200	MACH4^b	AEC^a
Pancytokeratin^a (M3515)	Monoclonal (AE1/AE3)	3 min/125^oC, plus citrate, pH 6.0	1:80	MACH4^b	AEC^a
S-100^a (Z0311)	Polyclonal	20 min/96^oC, plus citrate, pH 6.0	1:50	MACH4^b	AEC^a
Vimentin^c (18-002)^c	Monoclonal (V9)	3 min/125^oC, plus citrate, pH 6.0	1:200	MACH4^b	AEC^a

Diagnoses	Location			Total	% Total
Diagnoses	Stomach	SI	LI	Total	% Total
Epithelial
Papillary adenocarcinoma	0	2	15	17	19.3%
Acinar/tubular adenocarcinoma	2	4	4	10	11.4%
Mucinous adenocarcinoma	1	3	2	6	6.8%
Undifferentiated adenocarcinoma	2	1	2	5	5.7%
Signet-ring cell adenocarcinoma	2	0	0	2	2.3%
Tubular adenoma	1	0	0	1	1.1%
Mesenchymal
Leiomyosarcoma	1	4	9	15*	17.0%
Gastrointestinal stromal tumors (GIST)	0	3	7	11*	12.5%
Leyomioma	4	1	3	8	9.2%
Non-GIST/non-leiomyosarcoma	0	3	2	5	5.7%
Hemangiosarcoma	0	0	1	1	1.1%
Fibroma	0	0	1	1	1.1%
Hematopoietic
Mast cell tumor	0	1	2	3	3.4%
Plasma cell tumor	0	0	2	2	2.3%
Neuroendocrine
Neuroendocrine carcinoma (carcinoid)	1	0	0	1	1.1%
TOTAL	14	22	50	88*	100%

Brasil

Brasil

Primary nonlymphoid gastrointestinal neoplasms in dogs in Rio Grande do Sul

Neoplasmas gastrointestinais primários não linfoides em cães no Rio Grande do Sul

ABSTRACT: