Evaluation of Platelet Indices and Complete Blood Count in Canine Mammary Tumors

Abstract

Background: Malignant mammary tumors in humans and bitches cause hematological disorders such as anemia, erythrocytosis, thrombocytosis, hyperproteinemia, and leucopenia. Novel studies have been conducted on the predictive and prognostic values of platelet (PLT) indices in human breast cancer (HBC). However, there is little information about the alterations in hematological parameters in canine mammary tumors (CMTs). The aims of this study were to evaluate the platelet indices and complete blood count (CBC) parameters in bitches with and without mammary tumor and to assess the above mentioned parameters with regard to histological tumor types and grades.Materials, Methods & Results: A total of 71 bitches were enrolled in this study. The bitches in the study group were divided into 2 groups which consisted of malignant epithelial mammary tumors (group EMT; n = 43) and malignant mixed mammary tumors (group MMT; n = 12). Control group (group C) consisted of clinically and gynaecologically healthy 16 bitches. Blood samples were obtained to perform the CBC and PLT indices analysis. Histopathological examinations were carried out under a light microscope. Histological tumor types and malignancy grades were classified. The bitches with mammary tumor showed significantly increased PLT values and decreased hematocrit (HCT), hemoglobin (HGB) and mean corpuscular hemoglobin (MCH) values versus the healthy ones, regardless of the tumor type. However, in comparisons with the group C, mean platelet volume (MPV) and mean corpuscular hemoglobin concentration (MCHC) values were different only in the group MMT, while plateletcrit (PCT) and mean corpuscular volume (MCV) values were different only in the group EMT. Also white blood cell (WBC), PLT and PCT values were higher than the referenced laboratory ranges in grade 3 tumors. In the presented study, MPV was considerably correlated with PLT, platelet distribution width (PDW) and PCT. Also, PCT and PLT had high sensitivity and specificity to distinct EMT and MMT from the healthy bitches.Discussion: Microcytic and hypochromic anemia occurs due to the decrease in the amount of HGB. Levels of MCV, MCH, and MCHC in the HBC group were reported to be significantly lower than in humans without breast cancer. Although anemia did not occur in EMT and MMT groups, obtained significances in the HCT, HGB, MCV, MCH, and MCHC levels between the bitches with and without mammary tumor were in line with the previous reports. In this study, WBC levels in grade 3 tumors were significantly higher than grade1 tumors (P < 0.05). Whereas levels of WBC in grade 1 and grade 2 tumors were in referenced laboratory ranges, it was higher in grade 3. Increased level of WBC in grade 3 was supposed to be due to the rise in malignancy as previously reported. Thrombocytosis was detected in 48.83% and 41.66% of the bitches in EMT and MMT groups, respectively. The higher percentage of CMTs with thrombocytosis in this study might be due to the difference in referenced upper limit of PLT in previous studies. The elapsed time between tumor formation and clinical presentation could be another influencing factor. Although PLT and PCT values were not significant according to the histological grading in this study, both parameters were found to be higher in grade 3 than the normal reference values. Further studies conducted with higher populations may lead the differences in these parameters to significance. With the support of further studies, alterations in the above mentioned parameters in bitches may contribute in the diagnosis process, management of treatment and may constitute an easy way to have an idea about the prognosis of mammary tumors.