The purpose of this study was to evaluate the effect of mindfulness-based meditation and yoga on stress, self-esteem, body image and sexual adjustment in breast cancer patients.

The study was conducted in a single-center, prospective (pretest-posttest-2. month follow-up), two-arm (1:1), randomized controlled experimental design.

In this study, the effects of an 8-week structured mindfulness-based meditation and yoga program on stress, self-esteem, body image and sexual adjustment will be evaluated in women undergoing modified radical mastectomy. The 8-week interventions were conducted by the researcher. The researcher who performed these applications has a certificate of mindfulness meditation, yoga, breathing and movement trainer. Due to the nature of the research, the researcher is involved in the implementation of the mindfulness-based meditation and yoga program, data collection and data entry into the system. At the same time, the women in the experimental group had to be informed about the research. Therefore, researcher and participant blinding could not be performed. However, randomization was performed to prevent selection bias (1:1). The randomization process was performed by a statistical expert other than the researcher and communicated to the researcher. The participants included in the study were numbered from 1 to 41, preserving their random order in the list received from the hospital. The groups were divided into Group 1 and Group 2 by the statistician and the first group was determined as the experimental group and the second group as the control group by lottery method. The randomization table was created by making use of "http://calculatorsoup.com". Before the 8-week process started, 3 measurements were made to the participants: pre-test, post-test at the end of 8 weeks and follow-up measurement 2 months after the application.

Inclusion Criteria:

• Able to read and write Turkish,
• Who have undergone modified radical mastectomy surgery,
• Female patients between the ages of 30-55,
• Premenopausal patients,
• At least 3 months have passed since the mastectomy operation and all available treatments (chemotherapy and/or radiotherapy treatments),
• No condition that constitutes an obstacle for active sexual life (for sexual compatibility assessment),
• Those who have not undergone plastic and reconstructive surgery for the breast after modified radical mastectomy,
• Those who have no previous meditation and/or yoga experience,
• Those who do not have a diagnosis of a mental disorder of organic origin,
• Those who do not have substance and/or alcohol addiction,
• Those who do not have severe depression accompanying the disease,
• Those who do not have a physical disability that would prevent participation in the study,
• Those who agree to participate in the study will be included in the sample.

Exclusion Criteria:

• Patients who received neoadjuvant chemotherapy in the preoperative period,
• Patients under the age of 30 and over the age of 55,
• Patients who have undergone oncoplastic, breast-conserving surgery,
• Patients with previous experience of mindfulness, meditation or yoga will not be included in the study.

Due to the nature of the research, the researcher is involved in the implementation of the mindfulness-based meditation and yoga program, data collection and data entry into the system. At the same time, the women in the experimental group had to be informed about the research. Therefore, researcher and participant blinding could not be performed. The data obtained from the research were coded as Group 1 and Group 2 by the researcher and transferred to the analysis program. The statistical expert who performed the analysis had no knowledge about the groups. Thus, it was aimed to control statistical bias, control bias and detection bias.