Cancer anxiety, also known as fear of cancer or carcinophobia, is a common and understandable concern for many people. Whether you are a cancer survivor, have a family history of cancer, or are simply worried about your health, cancer anxiety can be overwhelming and impact your quality of life. The constant fear of developing cancer or the cancer returning can lead to intrusive thoughts, avoidance behaviors, and physical symptoms such as sleep disturbances and fatigue.
Fortunately, there are numerous expert-backed techniques and strategies that can help you manage and reduce your cancer anxiety. In this article, we will explore a range of psychological, lifestyle, and medical approaches to alleviate cancer-related fears and improve your overall well-being. By implementing these evidence-based techniques and seeking support when needed, you can take control of your anxiety and live a more fulfilling life.
Understanding Cancer Anxiety
Defining cancer anxiety and its prevalence
Cancer anxiety is a persistent and irrational fear of developing cancer or the recurrence of cancer in those who have already been diagnosed and treated. It is estimated that up to 50% of cancer survivors experience some level of anxiety related to their diagnosis and the potential for recurrence[1]. Cancer anxiety can also affect individuals with a family history of cancer or those who have undergone genetic testing and discovered a predisposition to certain types of cancer.
Common causes of cancer anxiety
There are several factors that can contribute to the development of cancer anxiety. These include a personal or family history of cancer, exposure to carcinogenic substances, and a heightened awareness of cancer risk factors through media and public health campaigns. Additionally, certain personality traits such as perfectionism and a tendency towards health anxiety can make individuals more susceptible to cancer-related fears[2].
Recognizing symptoms of cancer anxiety
Cancer anxiety can manifest in various ways, both emotionally and physically. Common symptoms include persistent and intrusive thoughts about cancer, avoidance of cancer-related topics or medical appointments, and excessive self-monitoring for signs and symptoms of cancer. Physical symptoms may include sleep disturbances, fatigue, and gastrointestinal issues[3]. It is important to recognize these symptoms and seek help to manage cancer anxiety effectively.
Impact of cancer anxiety on quality of life
Cancer anxiety can have a significant impact on an individual’s quality of life. It can lead to social isolation, strained relationships, and difficulty functioning in daily life. The constant worry and fear can also take a toll on physical health, leading to a weakened immune system and an increased risk of other health problems. Addressing cancer anxiety is crucial for maintaining overall well-being and fostering resilience in the face of health challenges.
Psychological Techniques to Manage Cancer Anxiety
Cognitive Behavioral Therapy (CBT)
Cognitive Behavioral Therapy (CBT) is a well-established and effective treatment for various forms of anxiety, including cancer anxiety. CBT helps individuals identify and challenge negative thought patterns and beliefs related to cancer, replacing them with more balanced and realistic perspectives. Through CBT, patients learn coping strategies to manage their anxiety symptoms and improve their overall emotional well-being[4].
Mindfulness and meditation
Mindfulness and meditation practices have been shown to reduce stress, anxiety, and depression in cancer patients and survivors. These techniques involve focusing on the present moment, acknowledging thoughts and feelings without judgment, and cultivating a sense of calm and relaxation. Regular practice of mindfulness and meditation can help individuals better manage their cancer anxiety and improve their quality of life[5].
Cognitive Behavioral Therapy | Mindfulness and Meditation | |
---|---|---|
Focus | Changing negative thought patterns | Present moment awareness |
Duration | Typically short-term (6-12 weeks) | Ongoing practice for long-term benefits |
Effectiveness | Well-established for various anxiety disorders | Growing evidence for reducing anxiety in cancer patients |
Relaxation techniques
Relaxation techniques, such as deep breathing, progressive muscle relaxation, and guided imagery, can help reduce the physical symptoms of anxiety and promote a sense of calm. These techniques can be practiced independently or with the guidance of a mental health professional. Incorporating relaxation techniques into daily life can help individuals better cope with cancer anxiety and improve overall well-being.
Journaling and expressive writing
Journaling and expressive writing can be powerful tools for processing emotions related to cancer anxiety. Writing about fears, concerns, and experiences can help individuals gain clarity, identify coping strategies, and find meaning in their journey. Studies have shown that expressive writing can lead to improvements in both physical and emotional health outcomes for cancer patients and survivors[6].
Visualization and guided imagery
Visualization and guided imagery involve using mental images to promote relaxation and reduce anxiety. By imagining peaceful and comforting scenes, individuals can create a sense of safety and calm, even in the face of cancer-related fears. Guided imagery can be practiced independently or with the help of a therapist or recorded scripts, and has been shown to be an effective complementary therapy for managing cancer anxiety.
Lifestyle Changes to Reduce Cancer Anxiety
Regular exercise and physical activity
Engaging in regular exercise and physical activity has been shown to reduce stress, improve mood, and boost overall well-being. For individuals struggling with cancer anxiety, incorporating exercise into their daily routine can be an effective way to manage symptoms and improve quality of life. Aim for at least 150 minutes of moderate-intensity exercise per week, such as brisk walking, swimming, or cycling[7].
Healthy eating and nutrition
Adopting a healthy, balanced diet can help reduce cancer anxiety by promoting overall health and well-being. Focus on consuming a variety of fruits, vegetables, whole grains, lean proteins, and healthy fats. Limit processed foods, sugary drinks, and excessive alcohol consumption. Studies have shown that a diet rich in plant-based foods and low in red and processed meats may help reduce the risk of certain types of cancer[8].
Pros | Cons |
---|---|
Improved overall health and well-being | Requires commitment and effort |
Reduced stress and anxiety levels | Results may not be immediate |
Increased sense of control and empowerment | Lifestyle changes alone may not be sufficient for severe anxiety |
Stress management techniques
Incorporating stress management techniques into daily life can help reduce cancer anxiety and improve overall well-being. Some effective stress management strategies include:
- Deep breathing exercises
- Progressive muscle relaxation
- Time management and prioritization
- Engaging in hobbies and leisure activities
Sleep hygiene and adequate rest
Getting sufficient, quality sleep is essential for managing cancer anxiety and promoting overall health. Establish a consistent sleep schedule, create a relaxing bedtime routine, and ensure your sleep environment is comfortable and conducive to rest. Aim for 7-9 hours of sleep per night. If you struggle with insomnia or sleep disturbances, consider talking to your healthcare provider about potential solutions[9].
Social support and connection
Maintaining strong social connections and seeking support from loved ones, friends, or support groups can be incredibly helpful in managing cancer anxiety. Sharing your fears and concerns with others who understand can provide a sense of validation and comfort. Engaging in social activities and hobbies can also help distract from anxious thoughts and promote a sense of normalcy and enjoyment in life.
Building a Support System
Importance of social support in managing cancer anxiety
Social support plays a crucial role in managing cancer anxiety and improving overall well-being. Having a strong support system can provide a sense of connection, validation, and comfort during challenging times. Studies have shown that individuals with strong social support networks tend to have lower levels of anxiety and depression, and better overall health outcomes[10].
Family and friends
Family and friends are often the first line of support for individuals struggling with cancer anxiety. It is important to communicate openly and honestly with loved ones about your fears and concerns. Share your needs and preferences for support, whether it be emotional support, practical assistance, or simply a listening ear. Remember that your loved ones may also be affected by your cancer anxiety, so be open to their feelings and needs as well.
Support groups and online communities
Joining a support group or online community for individuals affected by cancer can be a valuable source of support and understanding. These groups provide a safe space to share experiences, fears, and coping strategies with others who can relate to your situation. Many hospitals, cancer centers, and organizations offer support groups for various types of cancer and stages of the cancer journey[11].
Pros | Cons |
---|---|
Sense of belonging and understanding | May be emotionally challenging at times |
Access to information and resources | Potential for comparing experiences and increased anxiety |
Opportunity to help others and give back | Time commitment and scheduling conflicts |
Healthcare providers and mental health professionals
Healthcare providers, such as oncologists, nurses, and social workers, can be valuable sources of support and information for managing cancer anxiety. They can provide guidance on coping strategies, treatment options, and referrals to mental health professionals when needed. Mental health professionals, such as psychologists or counselors specializing in oncology, can offer targeted interventions and support for cancer anxiety[12].
Workplace and school support
For individuals balancing cancer anxiety with work or school responsibilities, it is important to communicate with employers or academic advisors about your needs and any necessary accommodations. Many workplaces and schools have policies and resources in place to support individuals affected by cancer, such as flexible scheduling, remote work options, or academic accommodations.
Faith-based and spiritual support
For some individuals, faith-based or spiritual support can be a source of comfort and strength in managing cancer anxiety. Connecting with a faith community, spiritual leader, or engaging in practices such as prayer or meditation can provide a sense of peace and perspective. However, it is important to recognize that spiritual support may not resonate with everyone, and it is okay to seek support from other sources that align with your beliefs and values.
Medical Management of Cancer Anxiety
Discussing anxiety with your healthcare team
It is crucial to openly discuss your cancer anxiety with your healthcare team, including your oncologist, nurses, and mental health professionals. They can provide valuable guidance, support, and referrals to appropriate resources. Be honest about your symptoms, concerns, and the impact of anxiety on your daily life. Your healthcare team can help you develop a comprehensive plan to manage your anxiety alongside your cancer treatment[13].
Medication options for managing anxiety
In some cases, medication may be recommended to help manage cancer anxiety. Common types of medications used include:
- Selective serotonin reuptake inhibitors (SSRIs)
- Serotonin-norepinephrine reuptake inhibitors (SNRIs)
- Benzodiazepines (for short-term relief of acute anxiety)
Your healthcare provider will work with you to determine if medication is appropriate and to find the best option based on your individual needs and medical history. It is important to discuss potential side effects and to follow your provider’s instructions for taking medication as prescribed.
Collaborating with mental health professionals
Working with mental health professionals, such as psychologists, counselors, or psychiatrists, can be highly beneficial in managing cancer anxiety. These professionals can provide evidence-based interventions, such as cognitive-behavioral therapy (CBT), mindfulness-based stress reduction (MBSR), or supportive counseling. They can also help you develop coping strategies, process emotions, and address any underlying mental health concerns[14].
Ask for referrals from your oncologist or healthcare team |
Check with your insurance provider for covered services and providers |
Look for professionals with experience in oncology or working with cancer patients |
Consider telehealth or online therapy options for convenience and accessibility |
Integrative and complementary therapies
Integrative and complementary therapies can be used in conjunction with conventional medical treatment to help manage cancer anxiety. Some examples include:
- Acupuncture
- Massage therapy
- Music therapy
- Art therapy
- Yoga and tai chi
These therapies can help reduce stress, promote relaxation, and improve overall well-being. However, it is important to discuss any complementary therapies with your healthcare team to ensure they are safe and appropriate for your specific situation[15].
Coping Strategies for Specific Situations
Waiting for test results or diagnosis
The period of uncertainty while awaiting test results or a diagnosis can be incredibly stressful and anxiety-provoking. To cope during this time, try the following strategies:
- Practice deep breathing or mindfulness exercises to help calm your mind and body
- Engage in distracting activities, such as reading, watching movies, or spending time with loved ones
- Write down your thoughts and fears in a journal to help process your emotions
- Seek support from friends, family, or a therapist to discuss your concerns[16]
During treatment and recovery
Undergoing cancer treatment and recovery can be physically and emotionally challenging. To manage anxiety during this time:
- Communicate openly with your healthcare team about any side effects or concerns
- Set realistic goals and expectations for yourself, and be kind to yourself on difficult days
- Engage in gentle physical activity, such as walking or stretching, as tolerated
- Practice relaxation techniques, such as progressive muscle relaxation or guided imagery
- Join a support group for individuals undergoing similar treatments[17]
Prioritize rest and sleep |
Eat a balanced, nutritious diet |
Stay hydrated |
Engage in activities that bring joy and relaxation |
Dealing with fear of recurrence
Fear of cancer recurrence is a common and persistent concern for many cancer survivors. To cope with this fear:
- Discuss your concerns with your healthcare team and develop a follow-up care plan
- Focus on factors within your control, such as maintaining a healthy lifestyle and attending regular check-ups
- Practice thought reframing techniques to challenge anxious thoughts about recurrence
- Engage in enjoyable activities and hobbies that bring a sense of purpose and fulfillment
- Seek support from other cancer survivors who can relate to your experiences[18]
Managing anxiety in the context of relationships
Cancer can impact not only the individual diagnosed but also their loved ones and relationships. To manage anxiety in the context of relationships:
- Communicate openly and honestly with your partner or family members about your feelings and needs
- Set boundaries and prioritize self-care to avoid caregiver burnout
- Seek couples or family therapy to address any relationship challenges and strengthen communication
- Attend support groups or workshops specifically for couples or families affected by cancer
Coping with anxiety related to end-of-life concerns
For individuals facing advanced or terminal cancer, anxiety related to end-of-life concerns can be particularly challenging. To cope with this anxiety:
- Discuss your fears and concerns with your healthcare team, including palliative care specialists
- Consider engaging in advance care planning to express your wishes and preferences for end-of-life care
- Seek support from hospice or end-of-life care services, which can provide emotional and practical support
- Engage in legacy projects or activities that bring a sense of meaning and purpose
- Lean on your support system, including family, friends, and spiritual or religious communities, for comfort and guidance
Maintaining Emotional Well-being in the Long-term
Importance of ongoing self-care and stress management
Maintaining emotional well-being in the long-term is crucial for cancer survivors and those living with chronic cancer anxiety. Ongoing self-care and stress management practices are essential to prevent burnout, reduce anxiety, and improve overall quality of life. Prioritize activities that promote physical, emotional, and mental health, such as regular exercise, healthy eating, sufficient sleep, and engaging in hobbies or interests that bring joy and relaxation[19].
Continuing professional support
Even after active cancer treatment has ended, it is important to continue seeking professional support when needed. This may include ongoing therapy sessions with a mental health professional, regular check-ins with your healthcare team, or participation in cancer survivorship programs. These resources can provide ongoing guidance, support, and tools for managing any lingering anxiety or emotional challenges.
Access to the latest information and resources |
Opportunity to address any new or persistent concerns |
Continued skill-building and coping strategy development |
Sense of connection and validation from professionals who understand your experiences |
Staying connected with support networks
Maintaining connections with support networks, such as family, friends, and cancer support communities, is crucial for long-term emotional well-being. These relationships provide a sense of belonging, understanding, and encouragement. Consider participating in survivorship events, volunteering with cancer organizations, or staying active in online support forums to maintain these valuable connections.
Embracing post-traumatic growth and finding meaning
Many cancer survivors experience post-traumatic growth, a positive psychological change that can occur as a result of facing highly challenging life circumstances. Embracing this growth and finding meaning in your cancer experience can contribute to long-term emotional well-being. This may involve:
- Reflecting on personal strengths and resilience developed during your cancer journey
- Redefining priorities and values based on your experiences
- Cultivating a sense of gratitude and appreciation for life
- Pursuing new goals, interests, or passions that align with your values[20]
Celebrating milestones and survivorship
Acknowledging and celebrating cancer survivorship milestones, such as treatment completion anniversaries or annual check-ups, can be a powerful way to reinforce emotional well-being. These milestones serve as reminders of your strength, resilience, and progress. Consider marking these occasions with meaningful activities, such as:
- Sharing your story or writing about your experiences
- Engaging in a symbolic activity, like planting a tree or releasing lanterns
- Spending quality time with loved ones who have supported you
- Setting new goals or intentions for the future
Empowering Yourself and Others
Advocating for your physical and emotional needs
Advocating for your physical and emotional needs is a critical component of empowering yourself during your cancer journey. This involves communicating openly and assertively with your healthcare team, expressing your concerns, and asking questions about your care. Remember that you are an active participant in your treatment and recovery process, and your input matters. Don’t hesitate to seek second opinions, request additional support services, or voice any discomfort or preferences regarding your care plan[21].
Educating yourself and staying informed
Empowering yourself also means staying informed about your cancer diagnosis, treatment options, and available resources. Engage in self-education by:
- Reading reputable books, articles, and websites about your specific cancer type and emotional well-being
- Attending educational workshops, webinars, or conferences for cancer patients and survivors
- Discussing the latest research and treatment advancements with your healthcare team
- Connecting with patient advocacy organizations and accessing their informational materials
By expanding your knowledge base, you can make more informed decisions about your care, better understand your experiences, and feel more in control of your situation.
Sharing your story and experiences
Sharing your cancer story and experiences can be a powerful way to empower yourself and others. Consider:
- Joining online forums or social media groups to connect with others who have similar experiences
- Participating in support group meetings or mentorship programs to share your insights and learn from others
- Writing a blog, journal, or memoir about your cancer journey as a form of self-expression and to help others feel less alone
- Speaking at cancer-related events or workshops to inspire and educate others[22]
By sharing your story, you can help break down stigmas, raise awareness, and provide hope and validation to others facing cancer.
Supporting and empowering others in the cancer community
Empowering others in the cancer community can be a rewarding way to make a difference and find a sense of purpose beyond your own cancer experience. Consider:
- Volunteering with cancer organizations or support programs to provide peer support, practical assistance, or fundraising efforts
- Advocating for policies, legislation, or research initiatives that improve cancer care and support services
- Participating in cancer awareness campaigns or community events to raise public understanding and support
- Donating to cancer research foundations or patient assistance funds to help advance treatments and support others in need[23]
Celebrating your strength and resilience
Finally, empowering yourself means acknowledging and celebrating your own strength and resilience. Take time to reflect on how far you’ve come, the challenges you’ve overcome, and the growth you’ve experienced. Celebrate your victories, no matter how small, and practice self-compassion on difficult days. Remember that you are not defined by your cancer diagnosis, but rather by the courage, determination, and grace with which you navigate your journey.
Frequently Asked Questions
Anxiety is a very common emotional response among cancer patients, affecting up to 30-50% of individuals diagnosed with cancer. The prevalence of anxiety can vary depending on factors such as cancer type, stage, and individual coping mechanisms.
Common symptoms of cancer-related anxiety include excessive worry, restlessness, irritability, difficulty concentrating, sleep disturbances, and physical symptoms such as muscle tension, rapid heartbeat, and digestive issues. These symptoms can vary in intensity and duration among individuals.
Unmanaged anxiety can potentially affect cancer treatment outcomes by impacting treatment adherence, decision-making, and overall quality of life. Anxiety may lead to missed appointments, difficulty following treatment plans, or hesitancy in communicating concerns with healthcare providers. Addressing anxiety through various interventions can help improve treatment outcomes and emotional well-being.
Effective coping strategies for managing cancer anxiety include practicing relaxation techniques such as deep breathing, meditation, or progressive muscle relaxation; engaging in regular physical activity; seeking support from loved ones, support groups, or mental health professionals; and practicing cognitive reframing techniques to challenge anxious thoughts. A combination of strategies tailored to individual needs and preferences is often most beneficial.
Loved ones can support someone with cancer anxiety by actively listening and validating their feelings, offering practical assistance with daily tasks or treatment-related needs, encouraging open communication about fears and concerns, and helping them access professional support resources when needed. Maintaining a supportive and non-judgmental presence can be incredibly valuable.
Yes, it is common and normal to experience anxiety even after cancer treatment ends. Many cancer survivors face fears of recurrence, uncertainty about the future, and challenges in adjusting to life after cancer. Ongoing self-care, stress management, and professional support can help manage post-treatment anxiety and promote long-term emotional well-being.
It is advisable to seek professional help for cancer-related anxiety when symptoms persist, interfere with daily functioning, or cause significant distress. If anxiety is impacting your ability to engage in treatment, maintain relationships, or enjoy life, it is important to reach out to a mental health professional experienced in working with cancer patients. Early intervention can prevent anxiety from escalating and improve overall well-being.
In some cases, medication may be prescribed to help manage severe or persistent cancer anxiety. Anti-anxiety medications, such as benzodiazepines or selective serotonin reuptake inhibitors (SSRIs), can be effective in reducing anxiety symptoms. However, medication should be used under the guidance of a qualified healthcare provider and in conjunction with therapy and other non-pharmacological interventions for optimal results.
Reference list
- Mitchell AJ, Chan M, Bhatti H, et al. Prevalence of depression, anxiety, and adjustment disorder in oncological, haematological, and palliative-care settings: a meta-analysis of 94 interview-based studies. The Lancet Oncology. 2011;12(2):160-174.
- Pitman A, Suleman S, Hyde N, Hodgkiss A. Depression and anxiety in patients with cancer. BMJ. 2018;361:k1415.
- Greer JA, Traeger L, Bemis H, et al. A pilot randomized controlled trial of brief cognitive-behavioral therapy for anxiety in patients with terminal cancer. The Oncologist. 2012;17(10):1337-1345.
- Traeger L, Greer JA, Fernandez-Robles C, Temel JS, Pirl WF. Evidence-based treatment of anxiety in patients with cancer. Journal of Clinical Oncology. 2012;30(11):1197-1205.
- Andersen BL, DeRubeis RJ, Berman BS, et al. Screening, assessment, and care of anxiety and depressive symptoms in adults with cancer: an American Society of Clinical Oncology guideline adaptation. Journal of Clinical Oncology. 2014;32(15):1605-1619.
- Carlson LE, Bultz BD. Efficacy and medical cost offset of psychosocial interventions in cancer care: making the case for economic analyses. Psycho-Oncology. 2004;13(12):837-856.
- Faller H, Schuler M, Richard M, Heckl U, Weis J, Küffner R. Effects of psycho-oncologic interventions on emotional distress and quality of life in adult patients with cancer: systematic review and meta-analysis. Journal of Clinical Oncology. 2013;31(6):782-793.
- Sheard T, Maguire P. The effect of psychological interventions on anxiety and depression in cancer patients: results of two meta-analyses. British Journal of Cancer. 1999;80(11):1770-1780.
- Duijts SF, Faber MM, Oldenburg HS, van Beurden M, Aaronson NK. Effectiveness of behavioral techniques and physical exercise on psychosocial functioning and health-related quality of life in breast cancer patients and survivors—a meta-analysis. Psycho-Oncology. 2011;20(2):115-126.
- Gudenkauf LM, Ehlers SL. Psychosocial interventions in breast cancer survivorship care. The Breast. 2018;38:1-6.
- Tatrow K, Montgomery GH. Cognitive behavioral therapy techniques for distress and pain in breast cancer patients: a meta-analysis. Journal of Behavioral Medicine. 2006;29(1):17-27.
- Deckx L, van den Akker M, Buntinx F. Impact of chronic diseases on quality of life in an aging population. Journal of the American Geriatrics Society. 2014;62(7):1339-1344.
- Chambers SK, Foley E, Galt E, Ferguson M, Clutton S. Mindfulness groups for men with advanced prostate cancer: a pilot study to assess feasibility and effectiveness and the role of peer support. Supportive Care in Cancer. 2012;20(6):1183-1192.
- Linden W, Girgis A. Psychological treatment outcomes for cancer patients: what do meta-analyses tell us about distress reduction?. Psycho-Oncology. 2012;21(4):343-350.
- Zhou ES, Partridge AH, Recklitis CJ. A pilot trial of brief group cognitive-behavioral treatment for insomnia in an adult cancer survivorship program. Psycho-Oncology. 2017;26(6):843-848.
- Stagl JM, Bouchard LC, Lechner SC, et al. Long-term psychological benefits of cognitive-behavioral stress management for women with breast cancer: 11-year follow-up of a randomized controlled trial. Cancer. 2015;121(11):1873-1881.
- Bower JE. Cancer-related fatigue—mechanisms, risk factors, and treatments. Nature Reviews Clinical Oncology. 2014;11(10):597-609.
- Carlson LE, Tamagawa R, Stephen J, Doll R, Faris P, Dirkse D, Speca M. Tailoring mind-body therapies to individual needs: patients’ program preference and psychological traits as moderators of the effects of mindfulness-based cancer recovery and supportive-expressive therapy in distressed breast cancer survivors. Journal of the National Cancer Institute Monographs. 2014;2014(50):308-314.
- Howell D, Oliver TK, Keller-Olaman S, et al. A pan-Canadian practice guideline: prevention, screening, assessment, and treatment of sleep disturbances in adults with cancer. Supportive Care in Cancer. 2013;21(10):2695-2706.
- Rajandram RK, Ho SMY, Samman N, Chan N, McGrath C, Zwahlen RA. Interaction of hope and optimism with anxiety and depression in a specific group of cancer survivors: a preliminary study. BMC Research Notes. 2011;4(1):519.
- Przezdziecki A, Sherman KA, Baillie A, Taylor A, Foley E, Stalgis‐Bilinski K. My changed body: breast cancer, body image, distress and self‐compassion. Psycho-Oncology. 2013;22(8):1872-1879.
- Fardell JE, Thewes B, Turner J, et al. Fear of cancer recurrence: a theoretical review and novel cognitive processing formulation. Journal of Cancer Survivorship. 2016;10(4):663-673.
- Lisy K, Langdon L, Piper A, Jefford M. Identifying the most prevalent unmet needs of cancer survivors in Australia: A systematic review. Asia-Pacific Journal of Clinical Oncology. 2019;15(5):e68-e78.