This proof-of-concept pilot study examined the demographics, Clinicopathological features, depressive symptom scores, and gut microbiome changes in breast cancer patients pre- and post-surgery. Among the 20 participants, the average age was 53.5 ± 5.7 years. The majority were married (60%) and postmenopausal (65%), with varied occupational backgrounds. Clinically, 70% of patients could palpate their mass, and 45% had lumps larger than 2 cm. Histological grading showed a distribution of 30% grade 1, 40% grade 2, and 30% grade 3, with 50% presenting with lymph node metastases. Molecular subtypes included 25% Luminal A, 35% Luminal B, 20% HER2-enriched, and 20% Triple-negative breast cancer.
Pre- and post-surgery assessments using GAD-7 and PHQ-9 scales revealed significant increases in anxiety and depressive symptoms, with a higher proportion of patients experiencing moderate to severe symptoms post-surgery. Higher education levels, palpable lumps, certain molecular subtypes (Luminal B and Triple-negative), lymph node metastases, and larger lump sizes (> 2 cm) were significantly associated with elevated post-surgery depressive symptoms scores.
Gut microbiota analysis showed substantial changes in beta diversity pre- and post-surgery. Post-surgery samples had higher beta diversity across all measures, with strong correlations between beta diversity indices and depressive symptom scores. These correlations were more pronounced post-surgery.
Our findings align with existing literature, indicating that breast cancer and its treatment can significantly alter gut microbiota composition. Similar alterations in gut microbiota among breast cancer patients both pre- and post-surgery have been observed, highlighting the potential impact of surgical treatment on gut microbial composition [19]. In prior study, diet quality has been suggested to influence mental health outcomes through microbiota-dependent and independent pathways, supporting the link between gut microbiota and depressive symptoms [20]. Additionally, Little et al identified lifestyle factors, such as reduced physical activity and changes in body composition post-diagnosis, as contributors to persistent gut microbiota alterations [21]. These emphasize the role of lifestyle modifications in maintaining gut health and mental well-being in breast cancer patients. Additionally, systemic effects of gut microbial dysbiosis have been linked to both breast cancer occurrence and bone metastasis [22].
Dieleman et al proposed using breast microbiota as a biomarker for breast cancer and therapeutic response, showing that higher gut microbiota diversity correlates with increased tumor-infiltrating lymphocyte expression in breast tissue [23]. This suggests a potential link between gut microbial diversity and immune responses, which may influence cancer progression and mental health outcomes. Mastectomy has been found to significantly alter gut microbiota composition and metabolites, indicating a shift towards a less favorable microbial profile post-surgery, potentially impacting overall health and well-being. [24]. Unique shifts in mammary and gut microbiomes in breast cancer patients, suggesting these changes could serve as early biomarkers for tumor development [25]. This underscores the interconnectedness of microbial communities within the body and their potential role in cancer pathogenesis. Additionally, correlations between gut microbiota composition, cardiorespiratory fitness, and psychosocial outcomes among breast cancer survivors suggest significant links between gut health, physical fitness, and mental well-being [26].
In conclusion, this study provides valuable insights into the demographic and Clinicopathological characteristics, depressive symptom scores, and gut microbiota changes in breast cancer patients undergoing surgery. The findings underscore the importance of considering multiple factors in understanding the holistic impact of surgery on patients' well-being and physiological changes. Further research in larger cohorts is warranted to validate these preliminary findings and explore potential interventions to support breast cancer patients throughout their treatment journey.