Prognostic markers

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For which tumors exist prognostic markers?

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Canine melanomas

In oral melanomas, histomorphological parameters such as the cellular morphology, the grade of pigmentation, and the mitotic count provide already information about biological behaviour and prognosis. The determination of the Ki67 index may increase the predictive value of the histomorphological parameters (Bergin et al., 2011).

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In cutaneous melanomas, the Ki67 index may also be employed to better predict the prognosis (Laprie et al., 2001).

 

Canine mast cell tumors

Cutaneous mast cell tumors are graded according to the 3-tier system of Patnaik and the 2-tier system of Kiupel. However, none of the two systems is 100% able to predict the prognosis in terms of relapse and metastases. For mast cell tumors of Patnaik grade 2 and Kiupel low grade the evaluation of the Ki67 index may give additional information about the biological behaviour. In addition, the evaluation of the KIT expression pattern may increase the information about the risk of relapse and metastases (Kiupel et al., 2004).

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For subcutaneous mast cell tumors, there is no established grading system available. The mitotic count has been proposed as prognostic factor. In addtion, the Ki67 index and the KIT expression pattern can be employed to increase the predictive value of the mitotic count (Thompson et al., 2011).

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Canine lymphomas

In canine lymphomas the histopathological grade of malignancy is determined by the mitotic count per hpf (high power field 400x) (Valli et al., 2011). For some lymphoma subtypes the evaluation of the Ki67 index may provide additional information about the biological behaviour (Sierra Matiz et al., 2018).