Peer-reviewed veterinary case report
Predicting survival in dogs with adrenal gland tumors using tissue
By van den Berg, Marit F et al.·Published in Veterinary and comparative oncology·2026·Department Clinical Sciences, Netherlands·View original on PubMed →
PetCaseFinder translated the abstract of this peer-reviewed paper into plain English so pet owners can read it. We do not publish original research — every detail traces back to the citation above. How we work →
Original publication title: Prognostic Value of a Histopathological Scoring System and the Ki67 Proliferation Index in Dogs With Phaeochromocytoma.
- Species:
- dog
Plain-English summary
A group of dogs with a type of adrenal tumor called phaeochromocytoma (PCC) underwent surgery to remove the tumor. After surgery, the researchers looked at different factors in the tumor samples to see which ones could help predict how well the dogs would do in the long term. They found that a specific measurement called the Ki67 proliferation index (which indicates how fast the tumor cells are growing) was very reliable. Dogs with a high Ki67 score had a poorer survival rate, while those that survived the immediate postoperative period had a good prognosis, living an average of over 6.5 years after surgery.
People also search for: dog adrenal tumor prognosis · phaeochromocytoma treatment in dogs · Ki67 index in dogs
Abstract
Canine phaeochromocytomas (PCCs) are neuroendocrine tumours with malignant potential. Metastatic disease remains the sole definitive evidence of malignancy. Histopathological criteria to predict long-term survival have not been established in dogs. This study evaluated the reproducibility and prognostic value of histopathological parameters derived from human scoring systems, along with the Ki67 proliferation index (PI), in dogs after adrenalectomy for PCC. Tumour samples from 41 dogs were assessed by a veterinary pathologist and pathology resident. Of 10 histopathological parameters examined, only necrosis, tumour cell spindling, and extension into adipose tissue achieved sufficient inter- and intra-observer agreement (≥ 0.40) for inclusion in survival analyses, while Ki67 PI demonstrated excellent reproducibility (≥ 0.95). A composite histopathological score was generated by summing these three parameters and a dichotomised Ki67 PI (optimal cutoff 18%), as determined by ROC analysis. Among the 41 dogs, eight died within 2 weeks postoperatively, leaving 33 long-term survivors with four tumour-related events. Kaplan-Meier analysis showed significantly poorer survival (p < 0.001) in dogs with a high Ki67 PI (≥ 18%), whereas the composite score showed a borderline significant association with outcome in Cox regression (p = 0.056; hazard ratio 2.80). Overall, dogs surviving the immediate postoperative period demonstrated a favourable prognosis (mean overall survival of 2456 days). These findings suggest that, in this cohort with few tumour-related events, the dichotomised Ki67 PI alone may serve as a clinically applicable prognosticator for canine PCC. However, further research in larger populations is needed to determine whether a composite score adds prognostic value and guides postoperative management.
Find similar cases for your pet
PetCaseFinder finds other peer-reviewed reports of pets with the same symptoms, plus a plain-English summary of what was tried across them.
Search related cases →Original publication on PubMed: https://pubmed.ncbi.nlm.nih.gov/40898874/