Understandably, mood disorders, including depression and anxiety, are the second most common side effect of cancer and its treatment. The symptoms of depression range from mild to severe, and they may interfere with your quality of life, including relationships and day-to-day living. Some symptoms are:
- Mood-related emotions, such as feeling sad, hopeless, irritable, numb or worthless.
- Behavioural changes, such as loss of interest in activities that you previously enjoyed, frequent crying, withdrawal from friends or family, and loss of motivation.
- Cognitive changes, including lack of concentration, difficulty making decisions, memory loss or negative thoughts. At its most extreme, these feelings or changes may include thoughts that life is not worth living, or thoughts of hurting yourself.
There are risks that may predispose you to developing depression, such as a previous diagnosis of depression or anxiety, a family history of depression, a lack of support from family and friends and financial problems.
If you experience severe depression, you should get help, which might involve both medication and psychological treatment. If you experience mild symptoms of depression, simply talking to a mental health professional might be enough.
Anxiety is described as having feelings of nervousness, being on edge or worried. Cancer anxiety is normal, and it might be related to fears that you have about the treatment and its side effects, or about recurrence and death. The uncertainty that a cancer diagnosis produces is enough to trigger anxiety, and your symptoms can be acute or chronic.
Acute symptoms include:
- Feelings of intense fear or dread.
- Feelings of detachment from reality.
- Rapid heartbeat or tachycardia.
- Increase in blood pressure.
- Chest pain.
- Shortness of breath.
- Feeling lightheaded.
- Nausea, diarrhea, heartburn, or a change in appetite.
- Abdominal pain.
Chronic symptoms can be:
- Excessive worrying.
- Muscle tension.
- Difficulty falling asleep.
- Difficulty concentrating.
- Trouble making decisions.
Treatment for anxiety is similar to that for other mood disorders. However, relaxation techniques are very helpful. These can include deep breathing, progressive muscle relaxation, guided imagery, meditation, hypnosis, biofeedback and yoga.
 Julie K. Silver MD, Jennifer Baima MD, R. Samuel Mayer MD. Impairment-driven cancer rehabilitation: An essential component of quality care and survivorship. CA: A Cancer Journal for Clinicians, July 2013.