Beyond Individual Acute Phase Protein Assessments: Introducing the Acute Phase Index (API) as a Prognostic Indicator...

Area of Science:

• Veterinary Medicine
• Immunology
• Oncology

Background:

• Acute phase proteins (APPs) are key components of the innate immune response during inflammation.
• An Acute Phase Index (API) integrates multiple APPs for enhanced outcome monitoring, proving valuable in human and veterinary medicine.
• Previous studies have explored APIs in livestock and dogs with Leishmaniasis, but their prognostic utility in canine neoplasia remains underexplored.

Purpose of the Study:

• To calculate an API for cancer-bearing dogs.
• To evaluate the prognostic significance of this API in relation to survival times and tumor types.
• To assess the role of specific APPs, including C-Reactive Protein (CRP), haptoglobin, albumin, and Paraoxonase-1 (PON-1), in canine cancer.

Main Methods:

• Sera were collected from 55 dogs with various neoplastic conditions.
• Dogs were categorized by tumor type and survival (less than or greater than 30 and 90 days).
• APIs were calculated using positive APPs (CRP, haptoglobin) and negative APPs (albumin, PON-1), with an alternative API excluding PON-1.

Main Results:

• Lower PON-1 levels were observed in round-cell tumors, indicating potential oxidative stress.
• APIs increased and PON-1 activity decreased in the terminal samples of dogs that did not survive the study.
• Elevated APIs and CRP levels were associated with shorter survival times in dogs with cancer.
• Specific API thresholds at first sampling predicted a significantly higher probability of death.

Conclusions:

• The calculated API shows potential as a prognostic biomarker in dogs with cancer.
• API values, particularly when combined with CRP levels, may aid in predicting survival outcomes.
• Further research into APIs could refine prognostic assessments and guide treatment strategies for canine neoplasia.