Thymic neuroendocrine tumors: a SEER database analysis of 160 patients

Thymic neuroendocrine tumors (NETs) are uncommon but malignant tumors of the thymus gland that are usually associated with systemic symptoms due to hypersecretion of biogenic amines from metastatic lesions. Due to the limited number of studies in the literature, very little is known about progress or trends made in the treatment and survival of patients with thymic NET.

We reviewed 160 patients diagnosed with thymic NET in the SEER database to evaluate patient demographics and their clinical course. Specifically, we evaluated the role of surgery and adjuvant radiation in the SEER cohort. We also performed univariable and multivariate Cox proportional hazard modeling of standard prognostic factors.

According to our results, thymic NETs afflict males and whites primarily. As expected, advanced stage correlates with poorer long-term survival (P = 0.009) and those patients who undergo surgery do better than their counterpart (P = 0.005). We did not observe any survival benefit for radiation delivered as a part of primary therapy. Univariable and multivariate analyses demonstrated that tumor stage (P = 0.009), grade (P = 0.002), surgical resection (P = 0.005), and tumor size (P = 0.02) correlated with overall survival.

Our study demonstrates that surgery continues to be the mainstay of treatment, and that there is a need to define a staging system for thymic NETs that can perhaps allow clinicians to formulate better therapeutic strategies for such patients.