Breast cancer patients’ population

Thirty newly diagnosed breast cancer patients (ages 38–67) were recruited for participation in this research from the Department of Clinical Oncology, Kasr EL-Aini, Cairo University, from January 2022 to January 2023. Cairo University’s ethics committee approved the protocol of this research (code: N-70–2022) at 20 October 2022. The documented pathological proofs of breast cancer and the clinical data were available from the Department of Clinical Oncology’s database, and the demographic data are available in Table 1.

Table 1 Breast cancer patients’ demography

Inclusion criteria were as follows: (1) Early diagnosed female breast cancer patients (have not received any type of cancer therapy); (2) breast cancer stage (0, I, II, III); (3) age ranging from 25 to 70; and (3) written informed consent. Exclusion criteria were as follows: (1) Patients with a history of comorbid psychiatric disorders and (2) patients with diseases other than cancer that affect their immune status.

Coping self-efficacy

Coping self-efficacy, defined as a belief about the ability of an individual to perform specific coping behaviors, was measured by the Coping Self-efficacy Scale (CSES) [17]. The CSES consists of 26 items that ask the participant to rate their confidence in his or her ability to cope effectively with a number of challenges. For example, participants are asked, “When things aren’t going well for you, or when you’re having problems, how confident or certain are you that you can do the following….” Then responses for each item were on 11-point scale: (0, cannot do at all), (5, moderately certain can do), and (10, certain can do).

The total score of the CSES is created by summing up the item’s rating. A higher score indicates higher coping self-efficacy [17]. The CSES has been widely used in studying coping self-efficacy in a range of patient populations. The CSES has good reliability (r = 0.92).

The permission to use Coping Self-efficacy Scale was obtained from the original authors.

Patient Health Questionnaire (PHQ-9)

The Patient Health Questionnaire (PHQ-9) is a short self-report scale consisting of nine items to indicate the presence and symptoms severity of major depressive disorder [18]. PHQ-9 scale is the preferred screening tool, particularly in resource-limited settings, and it is recommended by the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders [19].

Participants are asked to assess nine depressive symptoms items experienced by them over the last 14 days preceding the interview. The items share a common set of response options: (0, not at all), (1, several days), (2, more than half days), and (3, nearly every day). The total scores of the PHQ-9 scale range from zero to 27. Higher scores mean more severe depression [20].

The translation of the two scales was done by a rigorous translation approach; this involves three people who are highly familiar with Arabic and the English language.

Biological measurements

A 3-cm peripheral venous blood sample was collected from all patients between 9 am and 12 pm after the two psychological scales were filled to control for diurnal variation. A total of 1.5 cm of blood sample kept in a plain tube was spun at 3000 g for 10 min at 4–8 °C. Separated serum was stored at − 80 °C until assay for DHEA concentration. A total of 1.5 cm of the blood sample was dispensed in ethylenediaminetetraacetic acid (EDTA) tubes and was used to assay patients’ immunity by flow cytometry. All blood specimens were de-identified and coded using study identification numbers.

Serum dehydroepiandrosterone (DHEA)

Diametra ELISA kit (Boldn, UK) was used for immunoenzymatic determinations of serum DHEA on the TECAN analyzer (Switzerland) following the manufacturer’s specifications.

Each sample was measured in duplicate. The investigating lab has broad experience in performing these assays.

Breast cancer patients’ cellular immunity

The immunity tests evaluated B cells: cluster of differentiation CD 20 + , total T cells: CD3 + , T-helper cells: CD4 + , CD3 + CD4 + , and cytotoxic T cells: CD8 + , CD3 + CD8 + by using CytoFLEX-flow cytometry instrument from Beckman Coulter (Brea, CA, USA). The immunophenotyping was performed on lymphocytes derived from viable white blood cells and CD45 gating. The antibodies used were CD3-PC5.5, CD4-FTC, CD8-PE, CD20-FITC, and CD45-PC7. Reagents were from Beckman Coulter. The staining of the cells by the antibody was made according to the manufacturer’s specifications.

Statistical analysis

Quantitative variables were presented as range, mean, and standard deviation (SD). Qualitative variables were presented as frequency and percentage (%).

Pearson’s correlation coefficient was done to estimate the degree of correlation between two quantitative variables. Mediation model was conducted to estimate the effect of an independent variable on a dependent variable through a third explanatory one, known as a mediator variable.

Statistical analysis was done by SPSS v28 (IBM Inc., Chicago, IL, USA).