Low back pain as main symptom in Low-grade Appendiceal Mucinous Neoplasm (LAMN): A case report

Background: Low back pain is the leading cause of disability worldwide. It is also the main cause of the limitation of activities and absence from work in much of the world and a cause of great economic burden. The greatest percentage of low back pain is classified as nonspecific (i.e. not attributable to a defined pathology), while the others may concern specific pathologies of the lumbar region or suggest pathologies of non-musculoskeletal origin. Consequently, evaluating any signs and symptoms mimicking musculoskeletal conditions is crucial. Case description: This case report describes a 64-year-old female patient who first presented to the physiotherapist with two weeks of low back pain, complaining of a different clinical presentation than the previous episodes. The patient's pain started spontaneously and was located in the lumbar region over a diffuse area. Symptoms were constant throughout the day and did not change with movement. Based on the examination findings, the physiotherapist decided to make an urgent referral to the patient's General Practitioner. Outcomes: Following ultrasound examination and Computed Tomography scan, an 8.5 cm mass was confirmed in the abdominal region. It was surgically removed, and a histological diagnosis of Low-grade Appendiceal Mucinous Neoplasm (LAMN) was made. Conclusion: The physiotherapist's evaluation and decision-making process was fundamental in the patient's referral due to suspected pathology not within the scope of practice. This revealed a rare condition, which, according to the existing literature, is usually diagnosed in the event of collateral imaging findings or upon presentation of complex and/or emergency clinical pictures.