CP-179 Patients exceeding doxorubicin recommended cumulative dose

Abstract

BackgroundCardiotoxicity is a known risk of anthracycline treatment. The probability of developing impaired myocardial function is estimated to be 1–2% at a total cumulative dose of 300 mg/m2 of doxorubicin, whereas the risk dramatically increases (5–20%) when the doxorubicin cumulative dose (DCD) exceeds 450–500 mg/m2 . Although cardiotoxicity may also occur at lower doses, depending on age and pre-existing heart disease, this is considered to be the threshold above which the use of doxorubicin is contraindicated. Although this is a general concern when giving doxorubicin treatment, the likelihood of a patient reaching such a threshold might not be as high as expected.PurposeTo asses, in a clinical setting, the incidence of patients exceeding 450–500 mg/m2 DCD and to describe which protocols and tumour types are involved.Material and methodsPatients treated with doxorubicin from January 2004 to March 2015 were included.DCD was calculated for these patients and, for those exceeding 450 mg/m2 , treatment protocols and tumour types were recorded.Results961 patients were identified, 61% being solid tumour patients.The vast majority (98%) had not reached the maximum threshold of DCD recommended. Among those who did, 42.1% were haematological patients.Altogether, among those haematological patients treated with doxorubicin, only 2.1% surpassed it, all of whom were lymphoma patients. In the same way, solid tumour patients exceeding DCD were 1.9%, mostly sarcoma and breast cancer patients.Among patients diagnosed with sarcoma and treated with doxorubicin, 22.6% exceeded DCD, whereas only 0.6% of breast cancer patients treated with doxorubicin did so.When evaluating the 36 chemotherapy protocols that contained doxorubicin, only 7 were given to patients who surpassed DCD. Thus 20.6% of patients treated with a doxorubicin alone protocol and 3.3% of those who received a CHOP protocol reached DCD. As for the remaining 5 protocols, only 1 patient reached DCD.ConclusionThe risk of surpassing DCD was extremely low. Only in sarcoma patients might this be a concern.No conflict of interest.