Osteoblastomas are primary bone tumors with an affinity for the spine. They typically involve the posterior elements, although extension through the pedicles into the vertebral body is not uncommon. Histologically, they are usually indistinguishable from osteoid osteomas. However, there are different variants of osteoblastomas, with the more aggressive type causing more pronounced bone destruction, soft-tissue infiltration, and epidural extension. A bone scan is the most sensitive radiographic examination used to evaluate osteoblastomas. These osseous neoplasms usually present in the 2nd decade of life with dull aching pain, which is difficult to localize. At times, they can present with a painful scoliosis, which usually resolves if the osteoblastoma is resected in a timely fashion. Neurological manifestations such as radiculopathy or myelopathy do occur as well, most commonly when there is mass effect on nerve roots or the spinal cord itself. The mainstay of treatment involves surgical intervention. Curettage has been a surgical option, although marginal excision or wide en bloc resection are preferred options. Adjuvant radiotherapy and chemotherapy are generally not undertaken, although some have advocated their use after less aggressive surgical maneuvers or with residual tumor. In this manuscript, the authors have aimed to systematically review the literature and to put forth an extensive, comprehensive overview of this rare osseous tumor.
Michael A. Galgano, Carlos R. Goulart, Hans Iwenofu, Lawrence S. Chin, William Lavelle, and Ehud Mendel
Zachary R. Visco, David D. Liu, Owen P. Leary, Adetokunbo A. Oyelese, Ziya L. Gokaslan, Joaquin Q. Camara-Quintana, and Michael A. Galgano
Ventrally situated thoracic intradural extramedullary tumors are surgically challenging and difficult to access, and they may be complicated by extensive adhesions and calcifications. Selecting an approach for adequate ventral access is key to complete resection and optimization of outcomes. The authors present a case series of patients who underwent resection of ventral thoracic intradural extramedullary tumors and discuss indications and considerations for this technique. Additionally, they describe the use of a posterolateral transpedicular approach for resection of ventral thoracic intradural extramedullary tumors compared with other techniques, and they summarize the literature supporting its application.
From May 2017 to August 2020, 5 patients with ventral thoracic intradural extramedullary tumors underwent resection at one of the two academic institutions.
Patient ages ranged from 47 to 75 (mean 63.4) years. All tumors were diagnosed as meningiomas or schwannomas by histological examination. Three of the 5 patients had evidence of partial or extensive tumor calcification. Four of the 5 patients underwent an initial posterolateral transpedicular approach for resection, with positive radiographic and clinical outcomes from surgery. One patient initially underwent an unsuccessful traditional direct posterior approach and required additional resection 2 years later after interval disease progression. There were no postoperative wound infections, CSF leaks, or other complications related to the transpedicular approach.
Posterolateral transpedicular tumor resection is a safe technique for the treatment of complex ventrally situated thoracic intradural extramedullary tumors compared with the direct posterior approach. Anecdotally, this approach appears to be particularly beneficial in patients with calcified tumors.