What is depression? What may contribute to depression?

What is depression?

Depression is a treatable mood disorder that causes a persistent feeling of sadness and loss of interest.1Mayo Clinic. Depression (major depressive disorder). Viewed July 15, 2021. About one in four people with cancer experience severe depression.2National Cancer Institute. Depression PDQ: Health Professional Version. June 10, 2021. Viewed July 15, 2021. Some people may already have been depressed before learning they have cancer, and having cancer may affect their depression. 

Prolonged or severe depression can interfere with your functioning. “Depression may make it harder to cope with cancer treatment. It may also interfere with your ability to make choices about your care. As a result, identifying and managing depression are important parts of cancer treatment.”3Cancer.Net. Depression. American Society of Clinical Oncology. April 2016. Viewed July 15, 2021. 

Severe depression, called major depressive disorder or major depression, affects relationships and day-to-day life and makes functioning difficult.4Cancer.Net. Depression. American Society of Clinical Oncology. April 2016. Viewed July 15, 2021; American Cancer Society. Depression. February 1, 2020. Viewed July 15, 2021. 

What are the signs or symptoms of depression?

Suicidal thoughts

If you have suicidal thoughts, inform your physician or mental health provider as soon as possible. If you consider acting on suicidal thoughts, seek medical help immediately.

National Suicide Prevention Lifeline ›

In the US, this lifeline is open 24 hours a day, seven days a week, at 800-273-8255.

The International Association for Suicide Prevention ›

This site provides information on crisis centers and helplines around the world.

If you are a caregiver or loved one to someone you suspect or who openly tells you they’re having suicidal thoughts, you can help. 

If Someone Tells You They’re Thinking About Suicide: A #RealConvo Guide from AFSP ›

An excellent guide for what you can do if a loved one indicates they are having suicidal thoughts.

Guidance from AFSP if your loved one is in immediate danger:

  • Stay with them
  • Help them remove lethal means
  • In the US, call the National Suicide Prevention Lifeline: 988
  • Text TALK to 741741 to text with a trained crisis counselor from the Crisis Text Line free of cost, 24/7
  • Encourage them to seek help or to contact their doctor or therapist

Other signs and symptoms of depression

People experiencing depression may show physical, behavioral, and cognitive (thinking, analyzing, or problem-solving) symptoms. Symptoms of depression may appear right after a cancer diagnosis or any time during or after treatment. Symptoms range from mild to severe. 

Tell your care providers if you experience these, especially if you experience several and/or they last two weeks or longer.5Cancer.Net. Depression. American Society of Clinical Oncology. April 2016. Viewed July 15, 2021.

Mood-related symptoms
  • Feeling down
  • Feeling sad
  • Feeling hopeless
  • Feeling irritable
  • Feeling numb
  • Feeling worthless
  • Feeling anxious
Cognitive symptoms
  • Trouble focusing
  • Difficulty making decisions
  • Memory problems
  • Negative thoughts. In extreme situations, these may include thoughts that life is not worth living or thoughts of hurting yourself.
Behavioral symptoms
  • Loss of interest in activities that you used to enjoy
  • Frequent crying, or crying without provocation
  • Withdrawal from friends or family
  • Loss of motivation to do daily activities
Physical symptoms
  • Fatigue
  • Appetite loss
  • Inability to fall asleep or stay asleep (insomnia)
  • Feeling very sleepy most of the time (hypersomnia)
  • Excessive sleeping during the day
  • Sexual problems, such as lower sexual desire

Because cognitive and physical symptoms may be side effects of your cancer or cancer treatment, doctors place more emphasis on mood-related and behavioral symptoms when diagnosing depression with cancer.6Cancer.Net. Depression. American Society of Clinical Oncology. April 2016. Viewed July 15, 2021.

What may contribute to depression?

According to the National Cancer Institute, “Sadness and grief are normal reactions to the crises faced during cancer. All people will experience these reactions periodically. Normally, a patient’s initial emotional response to a diagnosis of cancer is brief, extending over several days to weeks, and may include feelings of disbelief, denial, or despair.”7National Cancer Institute. Depression PDQ: Health Professional Version. June 10, 2021. Viewed July 15, 2021.

Medical conditions


Depression can be triggered by an anxiety disorder, and many people have a diagnosis of both anxiety and depression.8Sawchuk CN. Depression and anxiety: Can I have both? Mayo Clinic. June 2, 2017. Viewed July 19, 2021. See Anxiety ›


A large waist-to-hip ratio is linked to depression among middle-aged women (not specific to cancer).9Wing RR, Matthews KA, Kuller LH, Meilahn EN, Plantinga P. Waist to hip ratio in middle-aged women. Associations with behavioral and psychosocial factors and with changes in cardiovascular risk factors. Arteriosclerosis and Thrombosis. 1991 Sep-Oct;11(5):1250-7. See Body Weight ›


Pain,10Tarrasch J, England P, Hurst VT, McDonald D, O’Keefe R, Cipriano C. Patients with metastatic disease are at highest risk for anxiety and depression in an orthopedic oncology patient population. JCO Oncology Practice. 2022 Jun 1:OP2100905. poor functional status,11Chen ML, Chang HK, Yeh CH. Anxiety and depression in Taiwanese cancer patients with and without pain. Journal of Advanced Nursing. 2000 Oct;32(4):944-51. and catastrophizing12Fischer DJ, Villines D, Kim YO, Epstein JB, Wilkie DJ. Anxiety, depression, and pain: differences by primary cancer. Supportive Care in Cancer. 2010 Jul;18(7):801-10. are each linked to higher risk of depression.

Pain may worsen depression, and depression may worsen pain.13Charalambous A, Giannakopoulou M, Bozas E, Paikousis L. Parallel and serial mediation analysis between pain, anxiety, depression, fatigue and nausea, vomiting and retching within a randomised controlled trial in patients with breast and prostate cancer. BMJ Open. 2019 Jan 24;9(1):e026809; Joyce C, Roseen EJ et al. Can yoga or physical therapy for chronic low back pain improve depression and anxiety among adults from a racially diverse, low-income community? A secondary analysis of a randomized controlled trial. Archives of Physical Medicine and Rehabilitation. 2021 Jun;102(6):1049-1058; Ciaramella A, Poli P. Assessment of depression among cancer patients: the role of pain, cancer type and treatment. Psycho-oncology. 2001 Mar-Apr;10(2):156-65. Alleviating either depression or pain to interrupt the feedback loop between them may provide relief from both symptoms.
See Pain ›

Diabetes and high blood sugar

Diabetes and high blood sugar are also linked to depression. See High Blood Sugar and Insulin Resistance ›


A cancer diagnosis, ongoing treatment, and adverse effects of treatment, such as sexual difficulties, can all increase risk of depression.14Hein I. Sexual distress, depression after prostate cancer treatment. Medscape. May 20, 2020. Viewed June 23, 2023; Tsao PA, Ross RD, Bohnert ASB, Mukherjee B, Caram MEV. Depression, anxiety, and patterns of mental health care among men with prostate cancer receiving androgen deprivation therapy. Oncologist. 2022 Apr 5;27(4):314-322; Dinh KT, Reznor G et al. Association of androgen deprivation therapy with depression in localized prostate cancer. Journal of Clinical Oncology. 2016 Jun 1;34(16):1905-12; Polacek LC, Nelson CJ. Androgen deprivation therapy and depression in men with prostate cancer treated with definitive radiation therapy: a psychological perspective. Cancer. 2019 Apr 1;125(7):1027-1029.


Some medications may contribute to depression, including these and many more.15National Cancer Institute. Depression PDQ: Health Professional Version. June 10, 2021. Viewed July 15, 2021.

  • Steroids
  • Propranolol
  • Interleukin-2a biological response modifier used as immunotherapy to boost the immune system in cancer therapy; also called IL-2 (IL-2)
  • Barbiturates
  • Some antibiotics
  • Some chemotherapy drugs

Risk factors for depression

You are more likely to experience depression if you have these risk factors.16Cancer.Net. Depression. American Society of Clinical Oncology. April 2016. Viewed July 15, 2021; Hammen C. Risk factors for depression: an autobiographical review. Annual Review of Clinical Psychology. 2018 May 7;14:1-28; Torquati L, Mielke GI, Brown WJ, Burton NW, Kolbe-Alexander TL. Shift work and poor mental health: a meta-analysis of longitudinal studies. American Journal of Public Health. 2019 Nov;109(11):e13-e20; Roman M, Irwin MR. Novel neuroimmunologic therapeutics in depression: a clinical perspective on what we know so far.Brain, Behavior, and Immunity. 2019 Sep 21. pii: S0889-1591(19)30536-7; Iguacel I, Huybrechts I, Moreno LA, Michels N. Vegetarianism and veganism compared with mental health and cognitive outcomes: a systematic review and meta-analysis. Nutrition Reviews. 2021 Mar 9;79(4):361-381; Okuyama M, Takaishi O et al. Associations among gastroesophageal reflux disease, psychological stress, and sleep disturbances in Japanese adults. Scandinavian Journal of Gastroenterology. 2017 Jan;52(1):44-49.

  • Stressful life events and circumstances, including financial burdens
  • Family history of depression or anxiety
  • Previous diagnosis of depression or anxiety
  • Interpersonal dysfunction
  • Lack of support from friends and family
  • Being female
  • Shift work
  • Inflammation
  • Vegan/vegetarian diet, possibly due to a deficiency of some B vitamins17Hall-Flavin DK. Vitamin B-12 and depression: Are they related? Mayo Clinic. June 1, 2018. Viewed May 20, 2022.
  • Gastroesophageal reflux disease (GERD)

Helpful link


Laura Pole, MSN, RN, OCNS

Senior Clinical Consultant
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Laura Pole is senior clinical consultant for CancerChoices. Laura is an oncology clinical nurse specialist who has been providing integrative oncology clinical care, navigation, consultation, and education services for over 40 years. She is the co-creator and co-coordinator of the Integrative Oncology Navigation Training at Smith Center for Healing and the Arts in Washington, DC. Laura also manages the “Media Watch Cancer News That You Can Use” listserv for Smith Center/Commonweal. In her role as a palliative care educator and consultant, Laura has served as statewide Respecting Choices Faculty for the Virginia POST (Physician Orders for Scope of Treatment) Collaborative as well as provided statewide professional education on palliative and end-of-life care for the Virginia Association for Hospices and Palliative Care.

For CancerChoices, Laura curates content and research, networks with clinical and organizational partners, brings awareness and education of integrative oncology at professional and patient conferences and programs, and translates research into information relevant to the patient experience as well as clinical practice.

Laura sees her work with CancerChoices as a perfect alignment of all her passions, knowledge and skills in integrative oncology care. She is honored to serve you.

Laura Pole, MSN, RN, OCNS Senior Clinical Consultant

Nancy Hepp, MS

Lead Researcher
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Ms. Hepp is a researcher and communicator who has been writing and editing educational content on varied health topics for more than 20 years. She serves as lead researcher and writer for CancerChoices and also served as the first program manager. Her graduate work in research and cognitive psychology, her master’s degree in instructional design, and her certificate in web design have all guided her in writing and presenting information for a wide variety of audiences and uses. Nancy’s service as faculty development coordinator in the Department of Family Medicine at Wright State University also provided experience in medical research, plus insights into medical education and medical care from the professional’s perspective.

Nancy Hepp, MS Lead Researcher

Maria Williams

Research and Communications Consultant
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Maria Williams is a research and communications consultant who brings over 15 years’ experience in research, consumer education, and science communication to CancerChoices. She has worked primarily in public health and environmental health.

Maria Williams Research and Communications Consultant

Last update: April 16, 2024

Last full literature review: November 2021

CancerChoices provides information about integrative in cancer care, a patient-centered approach combining the best of conventional care, self care and evidence-informed complementary care in an integrated plan cancer care. We review complementaryin cancer care, complementary care involves the use of therapies intended to enhance or add to standard conventional treatments; examples include supplements, mind-body approaches such as yoga or psychosocial therapy, and acupuncture therapies and self-care lifestyle actions and behaviors that may impact cancer outcomes; examples include eating health-promoting foods, limiting alcohol, increasing physical activity, and managing stress practices to help patients and professionals explore and integrate the best combination of conventionalthe cancer care offered by conventionally trained physicians and most hospitals; examples are chemotherapy, surgery, and radiotherapy and complementary therapies and practices for each person.

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