Introduction

Metastatic breast cancer continues to pose significant clinical challenges despite advances in targeted therapies and supportive care, which have extended survival and transformed the disease into a chronic, relapsing condition for many patients [1]. With increased survivorship comes greater complexity in care, as patients must manage not only ongoing oncologic treatment but also the long-term effects of metastasis, therapy-related side effects, and comorbidities that collectively impact daily function and quality of life [1].

Cancer recurrence does not always present with classic oncologic warning signs [2]. Instead, relapse may manifest subtly or atypically, often mimicking common musculoskeletal complaints such as back pain or sciatica, especially in patients who consider their cancer to be well controlled [3]. This diagnostic challenge is particularly pronounced in individuals with a history of bone metastases, who are at increased risk for skeletal complications yet may attribute new symptoms to benign musculoskeletal causes or routine physical activity.

Given that the incidence of breast cancer is projected to increase in regions like Hong Kong, non-oncology primary care providers, including chiropractors, must maintain a heightened index of suspicion when encountering new-onset musculoskeletal complaints in this demographic [4]. Epidemiological screening data demonstrate that a history of cancer is more predictive of current spinal malignancy in patients presenting with low back pain than any other patient-reported clinical sign, carrying a substantial positive likelihood ratio (+LR) of 7.3 [5]. Clinicians are positioned to detect early warning signs of disease recurrence, especially when symptoms are disproportionate to typical musculoskeletal findings or are accompanied by neurological changes [5]. However, there is limited literature on the role of chiropractors in the detection and management of metastatic disease, and guidance for safe, integrative care in this population remains sparse [6, 7]. We previously reported three cases of breast cancer presenting as chiropractic complaints [4-6]. This case report describes two patients: a 62-year-old female breast cancer survivor who presented with presumed sciatica and a 44-year-old female with constant lumbar pain and no known prior oncologic history, both of whom were found to have metastatic spinal disease. These cases illustrate the pivotal role of musculoskeletal clinicians in unmasking cancer recurrence, the complexity of survivorship, and the need for interdisciplinary collaboration to optimize patient outcomes.