心理的介入はがん再発の恐怖を軽減する(Abstract LBS10000)

About 50% of all cancer survivors and 70% of young breast cancer survivors report moderate to high fear of recurrence. The fear can be so distressing that it negatively affects medical follow-up behavior, mood, relationships, work, goal setting, and quality of life. Yet, interventions to alleviate this fear are lacking. 

In a phase II randomized clinical trial, a psychological intervention called Conquer Fear substantially lowered fear of recurrence immediately after the intervention, and three and six months later. General anxiety, cancer-specific distress, and quality of life were better in the psychological intervention group immediately after therapy.

The study was featured at the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting.

 "The reduction in fear of recurrence in the psychological intervention group was large enough to improve survivors' psychological and emotional wellbeing," said lead study author Jane Beith, MD, PhD, a Medical Oncologist at the University of Sydney in Australia, who developed the Conquer Fear intervention with colleagues, including psycho-oncologist Phyllis Butow, BA(Hons)Dip Ed, MClinPsych, MPH, PhD. "The majority of participants were young women with breast cancer, but we expect the intervention may be appropriate for other patients who have moderate to high fear of recurrence."

The Conquer Fear psychology intervention is based on a novel theoretical framework developed by the authors (the intervention was developed for research and is not yet used in clinical practice). Trained study therapists delivered the intervention in five 60- to 90-minute individual, face-to-face sessions over 10 weeks. Conquer Fear focuses on:

• Accepting the inherent uncertainty of whether the cancer would come back
• Teaching strategies to control worry
• Giving survivors more control over where they place their attention
• Helping them focus on what they want to get out of life
• Choosing a sensible level of cancer screening and sticking to it

Researchers randomly assigned 222 survivors of stage I-III breast cancer, colorectal cancer, or melanoma who reported high fear of recurrence to either the Conquer Fear intervention or relaxation training (control group). All survivors had completed cancer treatment two months to five years before enrolling in this study and were cancer free at the time.

Survivors in the control group received five 60-minute, individual, face-to-face relaxation sessions. The sessions were delivered over 10 weeks by trained study therapists and incorporated muscle relaxation, meditative relaxation, and visualization and quick relaxation techniques. Both groups received instructions for home-based practice.

To measure change in fear of cancer recurrence, researchers used total scores from a validated 42-item questionnaire called Fear of Cancer Recurrence Inventory or FCRI. The scores range from 0 to 168, with higher scores indicating worse fear of recurrence. Survivors completed the questionnaire at enrollment, immediately after the intervention, and three and six months later.

The average FCRI score at baseline was 82.7 in the intervention arm and 85.7 in the control arm. The primary outcome of the study, total fear-of-cancer-recurrence score, was reduced significantly more in the intervention group (by 18.1 points on average) than in the control group (by 7.6 points on average), immediately after the intervention. This represents a standardized effect size of 0.44, within the range considered clinically important.

FCRI scores continued to decrease over time, with significant difference between groups at 6 months, decreasing by 27.2 points on average in the intervention group and 17.8 points on average in the control group.

The researchers also explored other patient outcomes, including cancer-specific distress (how much someone is plagued with thoughts about cancer), general distress (anxiety, depression, and stress), and quality of life (covers independent living, physical pain, mental health, happiness, coping, relationships, and self-worth). The psychological intervention had a greater positive effect on these outcomes than relaxation training.

"The number of people surviving cancer is higher than ever before, but many survivors fear that the cancer will return even long after they have finished treatment. The hope is that the positive results of this fear-reducing intervention will pave the way for making it more widely available to patients," said Don S. Dizon, MD, FACP, ASCO Expert.

The authors note that while Conquer Fear is effective in a face-to-face format, it is a time- and resource-intensive intervention. Other formats, such as delivery via internet, in a group, or by phone, may be possible. A stepped care approach could also be considered, with only those with severe fear of recurrence receiving face-to-face intervention.

"In this study, the interventions were delivered by experienced psycho-oncologists. It is possible that community psychologists or other professionals who have basic training in cognitive therapy could deliver the interventions, given appropriate training and supervision," said Dr. Beith.

This study was funded by Cancer Australia, beyond blue and National Breast Cancer Foundation.