Intralesional Marginal Resection for Osteoblastoma in the Mobile Spine: Experience From a Single Center

Abstract

Osteoblastoma (OB) is a benign bone tumor with aggressive behavior and a tendency for local recurrence. The appropriate surgical strategy for spinal OB remains unclear. This retrospective study aimed to verify the clinical efficacy and safety of intralesional marginal resection of OB in the mobile spine. We enrolled 50 consecutive patients with spinal OB between January 2009 and December 2019. The tumors were staged based on the Enneking system, with 21 and 29 lesions being determined as stage 2 (St.2) and stage 3 (St.3), respectively. Among them, 42 patients underwent intralesional marginal resection, five underwent extensive curettage, and three underwent en bloc resection successfully since their lesions were limited to the posterior element in a single vertebra. We analyzed clinical characteristics, perioperative and follow-up images, surgical details, and follow-up data. Within a median follow-up duration of 50 (range: 24-160) months, six (12.0%) patients had local recurrence. The recurrence rates among patients who underwent intralesional marginal resection, curettage, en bloc resection were 7.1%(3/42), 60.0%(3/5), and 0%(0/3), respectively. The recurrence rate of intralesional marginal resection of St.3 lesions was slightly higher than that of St.2 lesions (7.7%[2/26] vs. 6.3%[1/16]). There were 16(38.1%), 3(60.0%), and 0 patients with surgical complications among those who underwent intralesional marginal resection, curettage, and en bloc resection, respectively. Local recurrence was observed in five (5/14, 35.7%) patients who had vertebral artery extension and in none who did not have vertebral artery extension (p = 0.02). Our findings suggest that intralesional marginal resection could be an appropriate treatment choice for patients with spinal OB, both St.2 and St.3 lesions, with an acceptable local recurrence rate and a low risk of complications. Vertebral artery extension could be a strong risk factor for local recurrence in patients with spinal OB.

Keywords: enneking system; osteoblastoma; resection; spine; treatment.

Figure 1

Case 4. A 28-year-old female patient with low back pain for 6 months, with rapid symptom progression to paralysis of the lower extremities within 2 weeks. An osteolytic lesion was located in the T11 vertebral body, right pedicle, transverse process, and lamina. She underwent an intralesional vertebrectomy; however, computed tomography (CT) and isotope bone scans at 20 months postoperative revealed a local recurrence. She underwent radiotherapy but refused advanced surgery. The recurrent lesion was stable and gradually ossified, as seen at the 16-month follow-up after radiotherapy. (A) Preoperative posteroanterior radiography. (B,C) Preoperative axial and coronal CT scans. (D) T2-weighted magnetic resonance imaging (MRI) scan. (E) Preoperative positron emission tomography-CT (PET-CT). (F) Posteroanterior radiography 1 week postoperatively. (G) Isotope bone scan 20 months postoperatively. (H) Axial CT scan 20 months postoperatively. (I) T2-weighted MRI scan 20 months postoperatively. (J) Axial CT scan 16 months after radiotherapy. (K) Isotope bone scan 16 months after radiotherapy.

Figure 2

Case 5. A 15-year-old male patient with local neck and night pain for 6 months. An osteolytic lesion was located in the C7 vertebral body, left pedicle, transverse process, and lateral mass, with left vertebral artery extension. He underwent intralesional marginal resection; however, positron emission tomography-computed tomography (PET-CT) 7 months postoperatively showed local recurrence. The patient underwent a second surgery through a posterior approach. There was no further recurrence at a 5-year follow up after the second surgery. (A) Preoperative posteroanterior radiography. (B,C) Preoperative axial and coronal computed tomography (CT) scans. (D): T2-weighted magnetic resonance imaging (MRI) scan. (E) Posteroanterior radiography 1 week after the first surgery. (F). Axial CT scan 1 week after surgery. (G,H) Axial CT scan 7 months after surgery. (I) T2-weighted MRI scan 7 months after surgery. (J) Isotope bone scan 7 months after surgery. (K) Isotope bone scan 3 years after the second surgery. (L) T2-weighted MRI scan 5 years after the second surgery.

Figure 3

Case 6. A 10-year-old female patient with a history of neck pain over 6 months. An irregular and heterogeneous lesion was located in the C5 right pedicel and transverse process, vertebral body, and lamina, with right vertebral artery extension. She initially underwent radiofrequency ablation; however, computed tomography (CT) examination at the 5-month follow-up revealed lesion enlargement. Subsequently, the patient underwent intralesional marginal resection through a posterior approach. Local recurrence was identified by CT at the 12-month follow-up. She underwent a C5 vertebrectomy through an anterior approach. No recurrence was observed at the 21-month follow up after the second surgery. (A) Posteroanterior radiography before radiofrequency ablation. (B,C) Preoperative axial and coronal CT scans before radiofrequency ablation. (D) T2-weighted magnetic resonance imaging (MRI) scan at 5 months after radiofrequency ablation. (E,F) Axial and coronary CT scan at 5 months after radiofrequency ablation. (G) Posteroanterior radiography 1 week postoperatively. (H) Axial CT scan 1 week postoperatively. (I) Axial CT scan 12 months postoperatively. (J) T2-weighted MRI scan 12 months postoperatively. (K) Posteroanterior radiography 1 week after the second surgery. (L) T2-weighted MRI CT scan 21 months after the second surgery.