Inflammatory low back pain-associated malignancies mimicking spondylarthritis.

Malignancy-related low back pain differs from SpA patients with a more severe clinical picture, higher acute phase reactants levels, and higher LDH values. Malignancies must be kept in mind in the differential diagnosis, and in order to validate our findings, the results of larger case series are needed, especially in terms of causative malignancies. Key Points • In malignancy-related inflammatory low back pain, the hematologic/solid ratio was similar, the interval between symptom and diagnosis was shorter, and acute phase reactant levels and LDH levels were significantly higher. • Malignancy-related inflammatory low back pain differs from axial SpA patients with a more severe clinical picture, higher acute phase reactants levels, and higher LDH values. • Malignancies must be kept in mind in the differential diagnosis of axial SpA.