Open AccessCanine Mast Cell Tumors: Correlation of Apoptosis and Proliferation Markers with Prognosis
Author(s) -
Scase Timothy J.,
Edwards David,
Miller Jodi,
Henley William,
Smith Ken,
Blunden Anthony,
Murphy Sue
Publication year - 2006
Publication title -
journal of veterinary internal medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.356
H-Index - 103
eISSN - 1939-1676
pISSN - 0891-6640
DOI - 10.1111/j.1939-1676.2006.tb02835.x
Subject(s) - medicine , ki 67 , survivin , proliferating cell nuclear antigen , hazard ratio , grading (engineering) , proportional hazards model , immunohistochemistry , pathology , gastroenterology , survival analysis , oncology , cancer , confidence interval , biology , ecology
The Patnaik histologic grading system is commonly used to predict the behavior of cutaneous mast cell tumors (MCTs) in dogs, but it is less useful for grade 2 MCTs because they exhibit considerable variation in biological behavior. In this retrospective study, immunohistochemical staining for Ki‐67, proliferating cell nuclear antigen (PCNA), and survivin and a standardized argyrophilic staining of nucleolar organizer regions (AgNOR) protocol were performed on 121 archived paraffin‐embedded specimens of canine cutaneous MCTs, for which clinical follow‐up data were available. Cox regression models indicated that the Ki‐67 score (hazard ratio, 1.92; P <.001) and mean AgNOR score (hazard ratio, 2.57; P < .001) were significantly associated with Patnaik grade and survival time. A binary Ki‐67 variable (cutoff point Ki‐67 score = 1.8) was a significant predictor of survival for dogs with grade 2 MCTs. The estimated 1‐, 2‐, and 3‐year survival probabilities for dogs with grade 2 MCTs and Ki‐67 scores less than 1.8 were 0.92, 0.86, and 0.77, respectively (SEs, 0.08, 0.14, and 0.23, respectively; median not estimable). The corresponding survival probabilities for dogs with grade 2 MCTs and Ki‐67 scores higher than 1.8 were 0.43, 0.21, and 0.21, respectively (SEs, 0.19, 0.18, and 0.18, respectively; median survival time, 395 days). No significant association was identified between survival and survivin score or PCNA score. This study shows that both mean AgNOR score and Ki‐67 score are prognostic markers for canine MCTs. The Ki‐67 score can be used to divide Patnaik grade 2 MCTs into 2 groups with markedly different expected survival times.