Spondylolisthesis and tumors: a treatment algorithm

Pars defect and spondylolisthesis are frequent conditions, while bone tumors-particularly the primaries-are rare. The contemporary occurrence can delay the diagnosis of the tumor, if symptoms are considered related to spondylolisthesis, or can make reconstruction more demanding. To our knowledge, only two case reports of this contemporary occurrence have been published in the literature. Being such rare, guidelines on surgical treatment have not been proposed yet.A retrospective review of patients treated for spine bone tumors by the senior author from 1990 to 2017 was performed to find cases of contemporary occurrence of spondylolisthesis and/or pars defect and spine bone tumors. General health data, radiological imaging, histological tumor diagnosis, treatment, and follow-up were analyzed and discussed.Among the 1870 patients treated for spinal tumors between 1990 and 2017 by the senior author, 14 cases of association between tumors and spondylolysis/spondylolisthesis were observed. The cohort includes five males (35.7%) and nine females (64.3%), aged 14-72. Mean age of patients at surgery time was 47.Interactions between spondylolisthesis and bone tumors of the spine are episodic. These two conditions rarely occur in the same patient. No treatment strategy has been described until now. The target of this paper is to propose an algorithm to surgically treat patients with concomitant bone tumor and spondylolisthesis. This classification identifies a treatment-oriented algorithm based on two major categories: type A, bone tumor arising on the same vertebra or to an adjacent level; type B, bone tumor arising at least one unit far from the spondylolisthesis. This algorithm can help the surgeon facing this rare combination of diseases in the appropriate preoperative planning.