Question

The risk of cardiotoxicity is generally proportional to the cumulative exposure of doxorubicin. The probability of developing cardiotoxicity is estimated to be 1 to 2% at a total cumulative dose of 300 mg/m2 of doxorubicin, 3 to 5% at a dose of 400 mg/m2, 5 to 8% at a dose of 450 mg/m2, and 6 to 20% at a dose of 500 mg/m2, when doxorubicin is administered every 3 weeks. There is an additive or potentially synergistic increase in the risk of cardiotoxicity in patients who have received radiotherapy to the mediastinum or concomitant therapy with other known cardiotoxic agents such as cyclophosphamide, taxanes, and trastuzumab. Cardiotoxicity can occur at lower doses in patients who have received mediastinal radiation or those that have underlying heart disease. Coadministration of coenzyme Q10 has actually shown potential benefit in decreasing cardiotoxicity.

Which of the following offers the highest risk for developing cardiotoxicity?
a) A cumulative dose of 300 mg/m2 of doxorubicin
b) A cumulative dose of 400 mg/m2 of doxorubicin
c) A cumulative dose of 450 mg/m2 of doxorubicin
d) A cumulative dose of 500 mg/m2 of doxorubicin

Answer 1

The highest risk for developing cardiotoxicity is at a cumulative dose of 500 mg/m2 of doxorubicin.

Step-by-step explanation:

The risk of developing cardiotoxicity from doxorubicin is generally proportional to the cumulative exposure of the drug. Based on the information provided, the highest risk of developing cardiotoxicity would be at a cumulative dose of 500 mg/m2 of doxorubicin. At this dose, the estimated probability of developing cardiotoxicity is 6 to 20% when doxorubicin is administered every 3 weeks. It is important to note that the risk of cardiotoxicity is further increased in patients who have received radiotherapy to the mediastinum or concomitant therapy with other known cardiotoxic agents.