J Vet Sci.  2018 Nov;19(6):827-834. 10.4142/jvs.2018.19.6.827.

Presurgical assessment of splenic tumors in dogs: a retrospective study of 57 cases (2012–2017)

• Lee M
• Park J
• Choi H
• Lee H
• Jeong SM

• KMID: 2427031
• DOI: http://doi.org/10.4142/jvs.2018.19.6.827

Abstract

The purpose of this study was to evaluate the clinical and imaging characteristics of canine splenic tumors and to establish guidelines for the presurgical assessment of splenic tumors in dogs. Fifty-seven dogs that underwent total splenectomy for the treatment of splenic tumors were evaluated by examining medical records, hematologic results, diagnostic imaging results, and histopathologic results. The maximum lesion size from ultrasonography was significantly different between malignant and benign tumors (p = 0.002). There was a correlation between tumor margination and type of splenic tumors (p = 0.045). Precontrast lesion attenuation on computed tomography was significantly different between splenic malignant and benign tumors (p = 0.001). The mean ± SD precontrast lesion attenuation of malignant tumors was 40.3 ± 5.9 Hounsfield units (HU), and for benign tumors, it was 52.8 ± 6.8 HU. In conclusion, some variables of the imaging examination could be used to distinguish the type of splenic tumor. Based on the study results, using a diagnostic flowchart would be effective in increasing the survival rate of patients with splenic malignant tumors. In addition, fine needle aspiration or magnetic resonance imaging prior to surgical exploration and histopathologic examination may be useful in achieving a more accurate diagnosis.

Keyword

dogs; flowchart; malignancy; spleen; tumors

MeSH Terms

Animals
Biopsy, Fine-Needle
Diagnosis
Diagnostic Imaging
Dogs*
Humans
Magnetic Resonance Imaging
Medical Records
Retrospective Studies*
Software Design
Spleen
Splenectomy
Survival Rate
Ultrasonography

Figure

• 

  Fig. 1 Representative ultrasonography images of splenic tumors. (A) The maximal diameter of the tumor was measured on the longest axis of the mass (bidirectional arrow). (B) The lesion number was one; i.e., a solitary tumor. Heterogeneity was evaluated as homogeneous (C) or heterogeneous (D). Echogenicity was evaluated as hyperechoic (E) or hypoechoic (F). Margination was evaluated as regular (G) or irregular (*) (H).

• 

  Fig. 2 Box-and-whisker plots of ages in dogs with benign or malignant splenic tumors. The boxes indicate the interquartile range, the horizontal lines within the boxes indicate the median value, and the whiskers indicate the range.

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  Fig. 3 Kaplan-Meier survival curves for dogs after splenectomy for malignant or benign splenic tumors. The 2-year survival rate for benign tumors was 77.9%, and the 15-week survival rates for other malignant tumors was 40% and was 0% for hemangiosarcoma.

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  Fig. 4 Relationship between tumor size of malignant splenic tumors and survival time. There was no significant correlation between malignant tumor size and survival time in dogs (p = 0.739).

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  Fig. 5 Proposed flowchart for presurgical assessment of splenic tumors in dogs. U/S, ultrasonography; CT, computed tomography; HU, Hounsfield units; FNA, fine needle aspiration.

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