espanolRESUMEN: Los carcinomas mamarios son relativamente comunes en hembras caninas con edades de alrededor 10 anos y representan un importante factor de morbilidad para estas hembras; la tecnica de citoinclusion es frecuentemente empleada en medicina humana como un metodo de diagnostico que permite proveer informacion rapida para la determinacion de una conducta terapeutica correcta, sin embargo, la efectividad de esta tecnica permanece poco estudiada en medicina veterinaria. El objetivo del estudio fue evaluar el grado de correlacion entre marcadores inmunohistoquimicos para citokeratina 5 (CK5), receptores de estrogenos y progesterona (RE y RP) entre la tecnica de citoinclusion y la tecnica histopatologica en carcinoma mamario. Veinticinco muestras de carcinoma mamario para la tecnica de citoinclusion e histopatologica fueron sometidas a procesamiento histologico, laminas fueron confeccionadas para la tincion mediante hematoxilina y eosina (HE), y la tecnica de inmunohistoquimica para identificar la expresion de RE, RP y CK5. Mediante la tincion de la HE fue encontrado una proporcion de concordancia del 100% entre el analisis de citoinclusion e histopatologico de carcinoma mamario. El analisis inmunohistoquimico evidencio una sensibilidad del 85,71%, 95,45% y 100% y un indice kappa de Cohen de 0,78, 0,84 y 0,95 para RE, RP y CK5, respectivamente, asi como 100% de especificidad P EnglishABSTRACT: Mammary carcinomas are relatively common ailments among female canines aged around 10 years old, presenting an important morbidity with an average survival of five years. The cytoinclusion technique is frequently employed in human medicine as the investigative method of choice as it quickly provides resources for the determination of the correct therapeutic response, however, the effectiveness of the technique in canines remains understudied in veterinary medicine. This study aims at evaluating the degree of correlation with immunohistochemical marking for cytokeratin 5 (CK5), oestrogen and progesterone receptors (ER and PR) between the cytoinclusion and the histopathology technique in mammary carcinomas. Twenty-five samples of mammary carcinoma, both for the cytoinclusion and histopathological techniques were submitted for histological processing; microscope slides were created for hematoxylin-eosin (HE) staining and the immunohistochemical technique (IHC) was assessed for the ER, PR and CK5 receptors. Through the HE staining, we reached a concordance rate of 100% between the cytoinclusion and the histopathological analysis in the diagnosis of carcinomas. The immunohistochemical assay presented sensitivity of 85.71%, 95.45% and 100% and Cohen’s kappa of 0.78, 0.84 and 0.95 for ER, PR and CK5, respectively, as well as 100% specificity and P