Rationale: Approximately one in three cancer patients and survivors experience significant psychological distress. Previous research has shown that mindfulness-based interventions such as mindfulness-based cognitive therapy (MBCT) can help reduce distress among cancer patients. However, MBCT typically takes place in face-to-face group sessions, which are not easily accessible to many cancer patients. Blended therapist-assisted (combination of group sessions and individual online sessions) and unguided online MBCT interventions may address this problem, however, research on effectiveness of these interventions is missing.

Objective: This three-armed, randomized controlled trial (RCT) evaluates the effectiveness and cost-effectiveness of blended therapist-assisted (blended MBCT) and unguided individual internet-based MBCT (online MBCT) compared to treatment-as-usual (TAU) for cancer patients. Secondly, consolidation of treatment effects is studied up to nine months post-treatment. Thirdly, possible working mechanisms and effect moderators are studied.

Study design: The current study is a RCT with three arms (blended MBCT, online MBCT and TAU) with assessments at baseline (T0), mid-treatment, post-treatment (T1) and 3 months follow-up (T2). At 3 months follow-up (T2), patients in the TAU arm will be crossed over to blended MBCT or online MBCT (random allocation). Uncontrolled follow-up assessments will be conducted at 6 (T3) and 9 months (T4) follow-up.

Study population: 254 adults (>18 years) who have or have had a cancer diagnosis (any stage/any type) will be randomized.

Intervention: Patients will be randomly assigned with a 1:1:1 ratio to one of three groups: (1) blended MBCT: patients will be invited to a blended therapist-assisted MBCT program, consisting of 8 weekly sessions (4 online group meetings, 4 online sessions with therapist assistance, and an online silent day), in addition to TAU; (2) online MBCT: patients will be invited to an individual internet-based MBCT program without assistance from a therapist, that consists of 8 weekly sessions and a silent day, in addition to TAU; (3) TAU: patients receive usual care, which can be medical, psychological or paramedical care, except mindfulness interventions.

Main study parameters/endpoints: Primary outcome is the difference in Hospital Anxiety and Depression Scale (HADS) total scores between patients in the blended MCBT and TAU arms and between the online MCBT and TAU arms post-treatment (T1).

About one in three cancer patients experience significant levels of psychological distress, requiring intervention from a health professional. Unfortunately, however, many cancer patients experiencing psychological symptoms do not receive treatment.

Effective psychological treatments for cancer patients are available. Evidence for the effectiveness of mindfulness-based interventions (MBIs) such as Mindfulness-based Stress Reduction (MBSR) and Mindfulness-Based Cognitive Therapy (MBCT) in oncology has rapidly increased. MBIs have beneficial effects on depression symptoms, anxiety, fear of cancer recurrence and fatigue. Also, preliminary results indicate that MBIs are cost-effective in cancer care.

However, there are known patient-reported barriers to engaging in face-to-face psychological interventions, such as investment of time, stigma, reluctance to return to the hospital, and indirect costs. In contrast, internet-based interventions are easily accessible and save travelling time. Evidence of over 100 trials suggests that internet-based treatments can be as effective as face-to-face treatments for psychiatric and somatic conditions. MBIs are also being delivered via Internet, but research on internet-based MBIs (eMBIs) has been mostly conducted in the general population.

Studies on the effectiveness of eMBIs in cancer patients are scarce. Our team conducted the first RCT comparing group MBCT and individual internet-based MBCT with TAU in patients with cancer. Therapist-assisted individual internet-based MBCT was similar to group MBCT in terms of treatment protocol, but took place individually and was guided one-on-one by a therapist on a weekly basis. Results indicated that both group MBCT and individual internet-based MBCT were significantly effective in reducing psychological distress in cancer patients compared to TAU. Moreover, both interventions significantly increased secondary quality-of-life outcomes with small to moderate effect sizes. Patients further improved over the course of the 9 months post-treatment, with patients who were less conscientious and less mindful at baseline benefitting more from therapist-assisted individual internet-based MBCT than group MBCT. Cost-effectiveness analyses demonstrated dominance of both interventions compared to TAU, indicating both higher quality of life and lower societal costs. In short, individual internet-based MBCT rendered MBCT much more accessible for cancer patients without compromising intervention efficacy or societal costs.

However, the proportion of patients receiving a lower dosage of MBCT than intended was substantially higher in individual internet-based MBCT than in group MBCT and although cost-effective, the individual internet-based MBCT proved to be resource intensive in terms of therapist assistance. Moreover, patients mentioned lack of peer support and the asynchronous communication with their therapist as important disadvantages of individual internet-based MBCT. Consequently, there is room to improve individual internet-based MBCT prior to implementation to ensure adherence and scalability.

To improve adherence and scalability, the investigators have developed two new versions of the effective online MBCT program with therapist assistance in a co-creation process together with relevant stakeholders. To improve adherence, a blended therapist-assisted MBCT (blended MBCT) was developed, combining four online group sessions with a therapist with four individual therapist-assisted online sessions. Furthermore, to improve scalability, unguided individual internet-based MBCT (online MBCT), which is similar to the previously studied individual internet-based MBCT protocol but without therapist guidance was also developed. As adherence to unguided interventions often is lower than intended, persuasive technology known to improve adherence was included, such as reminders and virtual coaches.

The current study primarily aims to investigate the effectiveness and cost-effectiveness of blended MBCT and online MBCT in comparison to treatment-as-usual (TAU) in a randomized controlled trial (RCT). Secondly, the aim is to test the consolidation of treatment effects up to nine months post-treatment. Thirdly, the investigators want to investigate working mechanisms and treatment effect moderators, to address how these programs work, and for whom.

The aim is to include 254 patients who were diagnosed with cancer (any stage, any tumor). After baseline assessment, patients will be randomized to the blended MBCT, unguided online MBCT or TAU (1:1:1 ratio). Outcome assessment for the RCT will occur at baseline (T0), immediately post-treatment (T1; primary endpoint) and three months follow-up (T2). Patients participating will also receive follow-up questionnaires at 6 months (T3) and 9 months (T4) post-treatment. At week 5 of both interventions (and at the same time during TAU), patients will be invited to complete a mid-treatment assessment, to look at working mechanisms. At 3 months follow-up (T2), patients in TAU will be randomized to the blended MBCT or unguided online MBCT.

Inclusion Criteria:

1. A cancer diagnosis, any tumor or stage
2. Computer literacy and internet access
3. Good command of the Dutch language
4. Willingness to participate in either MBCT intervention

Exclusion Criteria:

1. Previous participation in MBSR or MBCT (>4 sessions)
2. Severe psychiatric comorbidity that warrants acute treatment (psychosis, mania, severe personality disorders, suicidal thoughts)
3. Alcohol or drug dependence
4. Severe cognitive impairments

Upon request

12 months after the collection of the primary outcome

Approval of proposed purpose for data access