title: Flow cytometric evaluation of peripheral blood and bone marrow and fine-needle aspirate samples from multiple sites in dogs with multicentric lymphoma.
abstract: OBJECTIVE
  To determine whether the extent of disease in dogs with lymphoma can be assessed via flow cytometry and to evaluate the suitability of fine-needle aspirates from the liver and spleen of dogs for flow cytometric examination.
  
  
  METHODS
  44 dogs with multicentric B-cell (n = 35) or T-cell lymphoma (9) and 5 healthy control dogs. Procedures-Peripheral blood and bone marrow samples and fine-needle aspirates of lymph node, liver, and spleen were examined via flow cytometry. Logarithmically transformed T-cell-to-B-cell percentage ratio (log[T:B]) values were calculated. Thresholds defined by use of log(T:B) values of samples from control dogs were used to determine extranodal lymphoma involvement in lymphoma-affected dogs; results were compared with cytologic findings.
  
  
  RESULTS
  12 of 245 (5%) samples (9 liver, 1 spleen, and 2 bone marrow) had insufficient cellularity for flow cytometric evaluation. Mean log(T:B) values of samples from dogs with B-cell lymphoma were significantly lower than those of samples from the same site in dogs with T-cell lymphoma and in control dogs. In dogs with T-cell lymphoma, the log(T:B) of lymph node, bone marrow, and spleen samples was significantly higher than in control dogs. Of 165 samples assessed for extranodal lymphoma involvement, 116 (70%) tested positive via flow cytometric analysis; results agreed with cytologic findings in 133 of 161 (83%) samples evaluated via both methods.
  
  
  CONCLUSIONS
  Results suggested that flow cytometry may aid in detection of extranodal lymphoma involvement in dogs, but further research is needed. Most fine-needle aspirates of liver and spleen were suitable for flow cytometric evaluation.
authors.affiliation: Small Animal Hospital, University of Veterinary Medicine Hannover, 30559 Hannover, Germany. alexa.joetzke@tiho-hannover.de
authors.forename: Alexa E
authors.initials: AE
authors.lastname: Joetzke
authors.forename: Nina
authors.initials: N
authors.lastname: Eberle
authors.forename: Ingo
authors.initials: I
authors.lastname: Nolte
authors.forename: Reinhard
authors.initials: R
authors.lastname: Mischke
authors.forename: Daniela
authors.initials: D
authors.lastname: Simon
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D044963:Biopsy, Fine-Needle / Q000379:methods / Q000662:veterinary*; D001853:Bone Marrow / Q000473:pathology*; D004283:Dog Diseases / Q000175:diagnosis*; D004285:Dogs; D005434:Flow Cytometry / Q000379:methods / Q000662:veterinary*; D008099:Liver / Q000473:pathology*; D008223:Lymphoma / Q000175:diagnosis / Q000662:veterinary*; D013154:Spleen / Q000473:pathology*; D018709:Statistics, Nonparametric