A coincidence of HLA-B27 negative spondyloarthritis and paravertebral non-Hodgkin's lymphoma--a lesson to be learnt from the past experience.

We reported a case of a 71-year-old woman with progressive low back pain and neurologic symptoms of lower extremities, who in the background had the coexistence of spondyloarthritis (SpA) and non Hodgkin's lymphoma of the paravertebral location. This example describes a situation where SpA with minimal sacroiliac joints affection has nevertheless led to the overt axial SpA. This situation included undifferentiated or reactive SpA, as well as unusual disease context, presented with late-life disease onset, older age, female gender and no obvious hereditary predisposition. This combination of comorbid factors could allow environmental and disease-specific factors to accumulate over time and to, by modifying the primary, low-penetrant genetic background, lead to the development of lymphoma. By achieving better understanding of disease pathophysiology dynamic, we will be able to improve our capabilities to navigate biologic therapy in the future, in order to prevent the development of both, overt SpA and lymphoproliferative disease.