The Modulatory Role of Internet MBCT on Extracellular Vesicles and Distress in Cancer Patients - Study Protocol

Mindfulness-based interventions (MBIs), such as mindfulness-based stress reduction (MBSR), mindfulness-based cognitive therapy (MBCT), mindfulness-based cancer recovery (MBCR), have been showing promising results in different health-related and psychosocial outcomes in the context of cancer. More recently, the possibility of delivering MBIs using technological tools and resources, such as internet and applications, has been receiving much attention, also accompanied by promising findings. However, few randomized controlled studies have been conducted and published to date. Moreover, few studies have addressed the long-term stability and trajectory of gains across time. Also, even though prior evidence had suggested that face-to-face MBIs might modulate several biological markers (e.g., pro-inflammatory gene expression and inflammatory signaling; telomere length), as far as we know, no previous study addressed the impact of online MBIs on biological indices, especially on extracellular vesicles (EVs).

As primary objective, this study aims to investigate the effects of an internet-based MBCT intervention (vs. Treatment as Usual - TAU) on EVs (objective measure), as well as on psychological distress (subjective measure), considering a sample of distressed people with history of breast, prostate, and colorectal cancer.

As secondary objective, this study aims to investigate the effects of this same intervention on psychosocial outcomes, including quality of life, fear of cancer recurrence, emotion suppression, mindfulness, sleep quality, posttraumatic growth, health-related behaviours (physical activity; smoking habits), and perceived social support. The biological secondary outcomes studied will be: inflammatory response genes interleukins (ILs, IL-1, IL-6, IL-8, IL-10), interferon gamma (IFN-γ), tumour necrosis factor (TNF), and c-reactive protein (CRP); telomerase activity; antigens related to cancer (cancer antigen - CA 15-3; prostate-specific antigen - PSA; carcinoembryonic antigen - CEA); other health-related markers (adrenocorticotropic hormone - ACTH; erythrocytes number; hemoglobin glycosylated).


Eligibility Criteria:
Inclusion Criteria:

* Diagnosis of breast, prostate, or colorectal cancer;
* Cancer stage I - III;
* Primary cancer treatments completed between 3 months and 5 years (participants with ongoing adjuvant hormonal therapies will be included);
* Age between 18 and 65 years;
* Experiencing significant distress on the Distress Thermometer (DT ≥ 4)
* Willingness to accept randomization to one of the two study conditions and to attend the study for its duration;
* Ability to speak, read, and write in Portuguese and literacy to complete autonomously the self-report measures;
* Sufficient digital literacy with access to a device (e.g., smartphone; tablet; computer) with camera, microphone, and internet.

Exclusion Criteria:

* Concurrent diagnosis of severe psychiatric condition(s) (e.g., psychosis; substance abuse; bipolar disorder; suicidal ideation);
* Concurrent diagnosis of autoimmune disorder;
* Current use of antipsychotics;
* Current use of anti-inflammatory medication (corticotherapy);
* Undergoing trastuzumab therapy;
* Participation in a structured mindfulness program (e.g., MBCT; MBSR; Mindfulness-Based Cancer Recovery - MBCR) program in the past five years;
* Currently attending psychological consultation;
* Being pregnant or breastfeeding.