Purpose <p>Sleep disturbances are prevalent in breast cancer patients, worsening during treatment and impacting outcomes and quality of life. This study examines the interplay between hormones such as cortisol and melatonin, inflammation, sleep issues, and changes in circadian rhythm in breast cancer, highlighting the necessity of integrated treatment strategies.</p> Method <p>The review summarizes the results of current research on the physiological processes that underlie sleep disorders in patients with breast cancer. It looks into how hormone imbalances and disturbances in circadian rhythms affect tumour growth, metastasis, and resistance to treatment. It also assesses the potential of serum indicators and inflammatory markers as predictors and treatment targets. Additionally covered are the oncostatic qualities of cortisol and melatonin as well as their function in controlling circadian rhythms.</p> Results <p>Chemotherapy alters the circadian rhythms, immunological function, and metabolism of breast cancer patients. These disturbances induce chronic sleep difficulties in roughly 60% of individuals. These alterations activate inflammatory pathways, which increase tumour development and resistance to treatment. Melatonin counteracts these effects by lowering estrogen levels, decreasing tumour cell proliferation, and increasing cell adhesion. Despite their significant incidence, existing therapies for sleep disorders are ineffective.</p> Conclusion <p>The urgent necessity for all-encompassing treatment plans that incorporate chronotherapy and sleep control into the treatment of breast cancer is highlighted by this review. Targeted therapies that address sleep disorders may improve patient outcomes, increase the effectiveness of treatment, and improve the quality of life for patients with breast cancer.</p>