BackgroundPrechemotherapy absolute neutrophil count (ANC) cutoffs are arbitrary and vary across institutions and clinicians. Similarly, subjective guidelines are utilized for the administration of prophylactic antibiotics in neutropenic dogs.ObjectivesTo evaluate the impact of various ANC cutoffs on chemotherapy administration in dogs with lymphoma treated with CHOP chemotherapy and to determine whether an association between prechemotherapy ANC and subsequent toxicity exists. The secondary objective was to evaluate a currently used ANC cutoff to indicate prescription of prophylactic antibiotics.AnimalsDogs diagnosed with lymphoma treated with CHOP chemotherapy (n = 64).MethodsSix hundred and fifteen ANCs were stratified into 6 classes. The 3 ANC cutoffs 1.5 × 103/μL, 2.0 × 103/μL, and 2.5 × 103/μL were assessed. The presence of an association between prechemotherapy ANC class and toxicity was determined. Afebrile neutropenic dogs with ANC <1.5 × 103/μL but above the criteria for prophylactic antibiotics were evaluated.ResultsChemotherapy was not administered in 7% of visits with an ANC cutoff of 1.5 × 103/μL; chemotherapy would not have been administered in 10% and 16% of visits with an ANC cutoff of 2.0 × 103/μL or 2.5 × 103/μL, respectively. There was no association among the 3 lower prechemotherapy ANC classes and toxicity. All dogs with ANC 0.75–1.5 × 103/μL recovered spontaneously without medical intervention.Conclusion and Clinical ImportanceThe number of dose delays was minimized with a prechemotherapy ANC cutoff of 1.5 × 103/μL, and the prechemotherapy ANC class 1.5–1.99 × 103/μL was not associated with an increased toxicity. Further investigation of an ANC cutoff near 0.75 × 103/μL in which to prescribe prophylactic antibiotics is indicated.

A 6-year-old unilateral cryptorchid dog presented with episcleral haemorrhage and ecchymosis. The complete blood count was consistent with pancytopaenia. Abdominal imaging confirmed the presence of a caudal abdominal mass suspected to be a Sertoli cell tumour (SCT) with associated myelotoxicity. The presence of myelotoxicity induced thrombocytopaenia and the delay in obtaining serum oestradiol results could make it challenging to confirm hyperoestrogenism in suspected SCTs without overt feminisation. Preputial cytology was used as a rapid and simple way to diagnose hyperoestrogenism in a dog without overt signs of feminisation and where the risk of significant haemorrhage precluded abdominal mass sampling. This technique could potentially detect hyperoestrogenism before clinical signs of feminisation and can readily be carried out in first opinion practice. A postmortem examination following sudden deterioration confirmed the presence of an SCT in the retained testicle and intracranial haemorrhage secondary to thrombocytopaenia.