Chapter 321 - Complications of Cancer Therapy Flashcards
When do neutrophil nadirs typically occur after administering cytotoxic drugs?
When do platelet nadirs typically occur?
Neutrophils - 5-10 days (typically ∼7 days)
Platelets - 7-14 days
Which drugs typically cause clinically significant neutropenia?
Carboplatin, doxorubicin, CCNU, mitoxantrone, vinblastine, and vinorelbine
Cyclophosphamide and vincristine are less myelosuppressive, but either can cause severe neutropenia with higher doses.
Which drug is considered more platelet sparing?
cyclophosphamide
When do neutrophil and platelet nadirs typically occur after carboplatin?
14-21 days in both dogs and cats
Lomustine CCNU can have variable nadirs in cats when do these typically occur
occurring 7-28 days after and persisting as long as 14 days, especially with higher doses
Dogs with which gene mutation have a higher risk of side effects from some cytotoxic drugs? (vinca alkaloids (vincristine, vinblastine, vinorelbine), doxorubicin, mitoxantrone, taxanes, and dactinomycin)
ABCB1-1delta (MDR-1)
Typical breeds: Collies, Australian Shepherds, McNabs, Silken Windhounds, Long-Haired Whippets, Shetland Sheepdogs, and German Shepherd Dogs
When is it recommended to check CBC when administering chemotherapy?
Typically 7 days ± 14 days) post-chemotherapy (for neutrophil nadir).
Prior to administering a pulse dose of any cytotoxic agent
What are the general thresholds for neutrophils and platelets for delaying treatment for 2-7d to allow BM recovery?
neutrophil counts <1500 to 2000 cells/mcL
platelet counts <75,000 to 100,000 cells/mcL
What are some of the risk factors for developing sepsis following chemotherapy in dogs?
lower body weight, diagnosis of lymphoma, administration of doxorubicin or vincristine
In a study of 70 dogs with chemotherapy-induced febrile neutropenia what was the hospital stay and mortality?
average hospital stay of 3 days and a mortality rate of 8.5%
Which drugs typically cause transient thrombocytopenia
carboplatin, CCNU, dacarbazine, melphalan, dactinomycin, cytosine arabinoside, and doxorubicin
Which drugs can cause cumulative and sometimes irreversible thrombocytopenia when given chronically
Certain alkylating agents (CCNU, chlorambucil, melphalan)