Deep vein thromboses (DVTs) are significantly more common in the lower extremities, however up to 10% of all DVTs are located in the upper extremities.1,2
In addition to being less common, upper extremity DVTs (UE-DVTs) are also associated with less symptomatic pulmonary embolism and 12 month recurrence when compared with lower extremity DVTs2.
UE-DVTs are associated, however, with a slightly higher overall 3 month mortality (11%) when compared to lower extremity DVTs (7%)2.
With this in mind, UE-DVTs represent an important clinical identity that clinicians should be familiar with when treating patients with cancer.
UE-DVTs are located within the brachial, axillary, and/or subclavian veins, while the cephalic and basilic veins are considered superficial veins. UE-DVTs can be classified as either primary or secondary.1
Primary UE-DVTs have no obvious underlying cause or are secondary to a patient’s anatomy and compose up to 30% of all UE-DVTs.1
Secondary UE-DVTs occur in patients with conditions lending to a prothrombotic state such as malignancy or the presence of an indwelling central venous catheter (CVC). Approximately 50% of all UE-DVTs are secondary to the use of venous catheters.1
In addition to their underlying malignancy, patients with cancer may have multiple risk factors for developing UE-DVTs including relative immobility, risk of infections, chemotherapy, multiple surgical procedures, CVCs (including chest ports), prior DVTs, chemotherapy, history of chest radiation, and parenteral nutrition.1,2
Patients with lung adenocarcinoma or ovarian cancer may have a slightly higher risk for UE-DVT than other malignancies.2 Cancer is an underlying cause of UE-DVTs in approximately one-third of UE-DVTs.1
Therefore, when a presumably cancer-free patient is diagnosed with a “primary” UE-DVT, the patient’s case should be thoroughly evaluated to assess the risk for a potentially undiagnosed malignancy as a contributing factor to developing the UE-DVT.