Thoracic dumbbell spinal metastasis secondary to neuroendocrine tumor of unknown origin: Case report and literature review

Abstract

Background: Dumbbell tumors are typically benign schwannomas, neurofibromas, and meningiomas and only rarely there are malignant variants of these lesions or other malignant histotypes. Here, a 34-year-old male presented with a thoracic spinal dumbbell metastatic neuroendocrine carcinoma of unknown primary origin. Case Description: A 34-year-old male presented with 2 months of thoracic pain and progressive mid thoracic sensory loss. A post contrast thoracic MRI showed a dumbbell tumor localized between the T7 and T9 levels with extension laterally into the T7-T8 and T8-T9 foramina. The patient underwent a laminectomy for tumor resection following which his pain and gait improved. Histopathologically, the tumor demonstrated multiple rounded small cells with a Ki67 level around 30%, suggesting a malignant metastatic neuroendocrine tumor of unknown etiology. Conclusion: We successfully treated a 34-year-old male with a T7-T9 malignant spinal dumbbell neuroendocrine tumor of unknown etiology utilizing a decompressive laminectomy.