Which statement is true regarding risk factors for pulmonary embolism?

Pulmonary embolism (PE) is a serious condition that arises when a blood clot obstructs a pulmonary artery in the lungs, often originating from deep vein thrombosis (DVT). Risk factors for PE are quite diverse and can include various medical conditions and situations. The statement that recent surgery and immobilization increase the risk is accurate because both factors significantly contribute to venous stasis and the formation of clots.

Surgery, especially orthopedic procedures or those involving the pelvis and abdomen, can lead to periods of reduced mobility, making blood flow slower and more prone to clotting. Similarly, prolonged immobilization, such as long flights or bed rest, can contribute to venous stasis. Therefore, individuals who have undergone recent surgery or who are immobilized for other reasons are certainly at a greater risk for developing DVT, which can subsequently lead to PE.

The other choices incorrectly limit the understanding of risk factors for PE. For example, pulmonary embolism can and does occur in individuals without previous lung diseases, and many patients at risk for PE do not have a history of DVT or cancer as their only risk factors.