Five questions to help diagnose depression in the cancer patient

Diagnosing depression in cancer patients is difficult. In response to the rigors of chemotherapy and other treatments, such patients suffer physical difficulties that may also be associated with depression, including sleep disorders, loss of appetite, and decreased libido.

If you see a cancer patient in whom you suspect depression, you can help rule out cancer treatment-related symptoms if you ask the oncologist the following five questions:

1. Has the patient been depressed for most of the past 2 weeks? Most patients who are depressed for 2 or more weeks will usually meet the other DSM-IV criteria for depression.
2. What is the stage and location of the cancer? Research shows that the incidence of depression increases proportionately with the cancer’s progression.² Some studies suggest that patients with pancreatic cancer, more advanced cancer, or numerous cancerous tumors are more likely than other cancer patients to become depressed because of the increased level of cytokines (proteins that help fight cancer) in their systems. Patients with brain metastases are also susceptible to depression.
3. Which anti-cancer treatments are being administered? This is critical, since anti-cancer drugs may trigger depression. Higher rates of depression have been reported in patients taking interferon and interleukin for kidney cancer and melanoma, and dexamethasone for brain metastasis, because these drugs increase cytokine levels.³ Use of steroids to treat cancer has also been associated with depression.
4. Is the patient experiencing medical complications? For example, if a patient is about to undergo surgery or is vomiting because of chemotherapy, antidepressants with a long half-life have an advantage. Conversely, shorter-term antidepressants prevent toxicity and do not interact adversely with other drugs.
5. What is the patient’s life expectancy? A clinically depressed patient who is expected to die soon may benefit from psychostimulants, which quickly counterattack depression and the negative effects of chemotherapy. Though psychostimulants are not often used to treat depression in physically healthy patients, they can help depressed cancer patients who feel sluggish and fatigued or who are taking an opioid.