Proliferation Activity in Canine Gastrointestinal Lymphoma

Area of Science:

• Veterinary Pathology
• Canine Oncology
• Immunohistochemistry

Background:

• Gastrointestinal lymphomas in dogs are rare, with limited understanding of their subtypes and proliferation rates.
• Accurate characterization is crucial for diagnosis and treatment of canine lymphoid neoplasms.

Purpose of the Study:

• To classify canine gastrointestinal lymphoma samples using the WHO classification.
• To determine the Ki67 proliferation index using manual counting, digital image analysis, and visual estimation.
• To correlate the Ki67 index with lymphoma subtype, immunophenotype, mitotic index, grade, and tumor location.

Main Methods:

• Classification of 33 canine gastrointestinal lymphoma samples.
• Ki67 proliferation index assessment via manual counting, digital image analysis, and visual estimation.
• Correlation analysis between Ki67 index and clinicopathological features.

Main Results:

• The mitotic index positively correlated with the Ki67 index.
• Enteropathy-associated T-cell lymphoma type I and diffuse large B-cell lymphoma exhibited higher Ki67 indices than enteropathy-associated T-cell lymphoma type II.
• Significant differences in Ki67 indices were observed between grade 1 and grade 2 lymphomas.
• Strong agreement was found between manual counting and digital image analysis for Ki67 index determination.

Conclusions:

• Digital image analysis offers a reliable and user-friendly method for determining the Ki67 index in canine lymphoid neoplasms.
• Ki67 index variations correlate with specific canine gastrointestinal lymphoma subtypes and grades.
• This stratification aids in understanding canine gastrointestinal lymphoma biology and prognosis.