Question 283

Question:

A 47 year old woman presents to the ED complaining of a swollen left leg. The swelling began two days ago and occasionally causes pain. The patient has a history of breast cancer that is currently being treated with doxorubicin and paclitaxel. She recalls no significant family history. On exam the left leg is edematous below the knee with mild erythema; the right leg is normal. A venous cord is palpated just superior to the medial malleolus. Upon dorsiflexion of the left ankle, the patient winces in pain. Which of the following is a risk factor for the most likely cause of this patient’s symptoms?

Correct Answer: C. Breast cancer

This patient likely has a deep vein thrombosis (DVT). Whenever you see DVT, think Virchow’s triad. Virchow’s triad describes the most common causes of thrombosis – endothelial injury, stasis, and thrombophilia.

Cancer is a proinflammatory state that strongly predisposes towards thrombosis, and is an established major risk factor for DVT.

Female gender is not by itself a risk factor for DVT. However, estrogen therapy (whether OCPs or estrogen replacement) can be a risk factor in women.

Paclitaxel is an antineoplastic drug that targets microtubules, but does not predispose to thrombosis.

Knee arthritis does not predispose to DVT, unless it was so incapacitating as to lead to immobility.

Age of 47 is not a risk factor. Older age (>60) is a minor risk factor for DVT. Any unprovoked DVT in a younger person is an indication for a thrombosis workup.