Total resection of sacral giant cell tumor with en bloc resection, sacral nerve reconstruction, and custom 3D-printed implant: a case report with long-term follow-up

Abstract

Introduction

Giant cell tumor (GCT) of the sacrum is a rare, locally aggressive bone tumor. Surgical resection is the primary treatment, but preserving sacral nerve function remains challenging. We present a case of sacral GCT treated with a novel nerve-preserving en bloc resection technique, resulting in long-term tumor control and functional recovery.

Case presentation

A 33-year-old male presented with progressive sacral pain and neurological symptoms. Imaging revealed a sacral GCT involving the S1 vertebral body and nerve root canal. The patient underwent en bloc resection with sacral nerve preservation and reconstruction, along with custom 3D-printed prosthesis implantation. Postoperative recovery was uncomplicated, with preserved bowel, bladder, and lower limb function. There was no evidence of recurrence during the 8-year follow-up period.

Clinical discussion

Sacral GCTs present substantial surgical challenges due to their proximity to critical neurovascular structures. While en bloc resection effectively reduces recurrence rates, it often compromises sacral nerve function. Our technique successfully preserved key sacral nerve roots, leading to superior postoperative functional outcomes compared to conventional approaches. A review of relevant literature supports the advantages of nerve-sparing strategies in sacral tumor surgery.

Conclusion

This case highlights the feasibility and benefits of sacral nerve-preserving en bloc resection for GCT. The long-term follow-up confirms durable tumor control and robust functional recovery, suggesting its potential as a preferred surgical approach for carefully select cases.

Highlights

• •Novel Surgical Approach: Presents a novel technique for total sacral GCTB resection with intraoperative nerve dissection, transection, and anastomosis.
• •Nerve Preservation & Reconstruction: Prioritized sacral nerve preservation and reconstruction to minimize postoperative neurological deficits.
• •Favorable Long-Term Outcome: Excellent long-term outcome: independent ambulation, no recurrence at 8-year follow-up.
• •Clinical Implications: Valuable insights for balancing tumor resection and neurological function preservation in surgical strategies.

1. Introduction

The management of spinal giant cell tumor of bone (GCTB), particularly when located in the sacrum, presents a complex surgical challenge due to the tumor's locally aggressive nature and the associated risk of recurrence [1,2]. Complete surgical resection remains the preferred treatment when feasible [3]. GCTB is a benign but locally aggressive tumor with a high potential for recurrence and significant morbidity. Its progression can lead to severe bone destruction and neurological deficits, especially when located in the sacrum. Current surgical strategies for sacral GCTB management include intralesional curettage and total sacrectomy. Curettage is technically simpler but carries a high recurrence rate, while total sacrectomy offers better oncological control but is associated with significant functional impairment, including lower limb paralysis, bowel and bladder dysfunction, and sexual dysfunction.

We present a case in which complete tumor resection was accomplished while preserving sacral nerve function through en bloc resection and meticulous nerve reconstruction. Additionally, a custom 3D-printed prosthesis was employed to restore spinal stability. Long-term follow-up demonstrated excellent outcomes, with no recurrence and sustained neurological function.

2. Case report

Our work has been reported in line with the SCARE Guidelines 2023 criteria [4].

A 33-year-old male presented with a one-year history of persistent low back pain, which progressed to right lower limb pain one month prior to presentation. Physical examination revealed diminished sensation in the lateral and medial aspects of the right lower leg, a reduced right ankle reflex compared to the left, and a positive straight leg raise test with reinforcement on the right side. Imaging studies (Fig. 1) identified a lesion within the S1 vertebral body exhibiting features suggestive of malignancy. MRI, performed using a 1.5 T scanner with T1-weighted, T2-weighted, and contrast-enhanced sequences, demonstrated a lytic lesion in the S1 vertebral body. CT scans confirmed lytic bone destruction with high metabolic activity, raising suspicion for GCTB or multiple myeloma. A CT-guided biopsy yielded histopathological findings consistent with GCTB.

Fig. 1.

Preoperative Imaging of the Lumbosacral Spine. (A-C) Preoperative sagittal, coronal, and axial CT scans of the lumbosacral spine, respectively, demonstrating a lytic lesion within the S1 vertebra, characterized by cortical destruction and extension into the spinal canal, with encroachment upon the right S1 nerve root. (D—F) Corresponding sagittal, coronal, and axial preoperative MRI scans, confirming the expansile growth of the tumor extending into the spinal canal and involving the right S1 nerve root, without significant surrounding soft tissue invasion.

Preoperative planning involved defining osteotomy margins and designing a custom 3D-printed titanium alloy prosthesis (Fig. 2 A-C). To minimize intraoperative blood loss, the patient underwent preoperative vascular embolization. The surgical procedure, lasting 14 h, was executed in three stages via a combined anterior-posterior approach (Fig. 2 D-G). Initially, an anterior retroperitoneal approach was utilized to protect abdominal viscera and major blood vessels, facilitating precise anterior osteotomy planning. The resection plane extended from the L5-S1 disc superiorly to the upper edge of the S2 vertebra inferiorly, and laterally to the sacroiliac joints, ensuring en bloc tumor removal and minimizing recurrence risk. Subsequently, a posterior approach was employed for L3-L5 and iliac screw fixation, providing spinal stability. The posterior elements uninvolved by the tumor were resected en bloc, with the osteotomy plane carefully aligned with the anterior resection level to achieve complete tumor removal. In the final stage, the anterior approach was reestablished to perform en bloc resection of the affected S1 vertebral body, including the encased segment of the right S1 nerve root. Instead of intra-tumoral nerve dissection, the right S1 nerve root was transected at the tumor's proximal and distal margins and reconstructed using microsurgical techniques after tumor removal. Finally, the custom 3D-printed prosthesis was implanted and secured with screws. Histopathological examination confirmed the diagnosis of giant cell tumor of bone, revealing typical features including mononuclear stromal cells and osteoclast-like giant cells (Fig. 2H).

Fig. 2.

Surgical Planning and Intraoperative Findings. (A, B) Preoperative osteotomy planning and 3D model illustrating the positioning and fit of the custom-designed 3D-printed metal prosthesis. (C) The patient-specific 3D-printed porous titanium alloy prosthesis. (D) Intraoperative posterior approach view following spinal canal decompression and posterior fixation system placement. (E) Intraoperative anterior approach view showing the implanted custom prosthesis in situ. (F) Intraoperative image of the anastomosed right S1 nerve root post-tumor resection. (G) En bloc resected S1 vertebral body, demonstrating complete tumor removal. (H) The histopathological examination revealing typical features of GCTB, including mononuclear stromal cells and osteoclast-like giant cells.

Postoperatively, the patient exhibited satisfactory neurological recovery. At three weeks, he experienced mild back extension weakness and residual numbness in the right S1 dermatome but maintained independent standing ability with intact bowel and bladder function. By six months, muscle strength and sensory function had improved, enabling independent ambulation. The S1 dermatome numbness gradually resolved over six months. Muscle strength in the S1 nerve-innervated muscles improved from 3/4 at three weeks to 4/5 at six months. At 18 months, there was no evidence of recurrence, with stable internal fixation and full mobility. At three years, revision surgery was performed due to rod breakage, involving four-rod fixation and iliac bone graft fusion (Fig. 3). At the latest follow-up, eight years postoperatively, the patient remained recurrence-free, with stable internal fixation, full mobility, and normal sphincter control.

Fig. 3.

Postoperative and Follow-Up Radiographs. (A, B) Coronal and sagittal radiographs one week postoperatively, demonstrating the implanted prosthesis and stable fixation. (C, D) Coronal and sagittal radiographs 38 months postoperatively, revealing rod breakage. (E, F) Post-revision fixation with four-rod reinforcement following internal fixation failure, demonstrating improved stability.

3. Discussion

The unique anatomical location of sacral tumors poses significant surgical challenges. Anteriorly, the sacrum's proximity to vital structures, including major blood vessels and visceral organs, complicates surgical access. Laterally, the iliac bones further impede surgical approaches. Moreover, the tumor's location within the pelvic cavity often allows for substantial growth before the onset of clinical apparent symptoms.

Surgical management of sacral GCTB typically involves intralesional curettage, marginal or wide resection, and en bloc resection, each with distinct oncological and functional implications. Intralesional curettage, while less invasive and associated with reduced morbidity, is linked to a significantly elevated recurrence rate, reported to a range from 50 to 60 % in sacral lesions [5,6]. The average time to recurrence following curettage has been documented as approximately 12–24 months [7,8]. To mitigate recurrence risk, some studies advocate for curettage combined with adjuvant therapies, such as cryotherapy, phenol application, or cement augmentation; however, these methods do not entirely eliminate the potential for tumor recurrence [[9], [10], [11]].

En bloc resection has demonstrated substantially lower recurrence rates in sacral GCTs. A meta-analysis by Li et al. [12] confirmed that en bloc resection significantly reduces recurrence compared to other surgical modalities. Studies have also reported no recurrence during follow-up periods ranging from 31 to 203 months in patients undergoing en bloc resection for sacral GCTs [13]. Nevertheless, this approach is technically demanding, particularly in the sacral region where achieving negative margins is challenging due to proximity of critical neurovascular structures. The potential for functional deficits, such as sacral nerve dysfunction, further complicate surgical decision-making. In this case, we employed a combined approach to ensure safe and effective en bloc tumor removal while preserving critical structures.

Regarding sacral nerve reconstruction, several studies have investigated the impact of such procedures on patient limb function. Zheng et al. [14] reported on five cases of sacral nerve root anastomosis following en bloc resection of sacral tumors, with only two patients experiencing functional improvements. This suggests that while sacral nerve reconstruction is promising, its efficacy may vary. Similarly, Li et al. [15] evaluated hemisacrectomy outcomes contralateral sacral nerve preservation in sacral malignancy patients, finding that nerve preservation contributed to improved postoperative function. Furthermore, a systematic review by Garg et al. [16] examined functional outcomes following nerve reconstruction in extremity soft tissue sarcomas, highlighting the importance of nerve reconstruction for restoring sensation and function in limb salvage procedures. However, the success of these interventions is influenced by factors such as the extent of nerve involvement and surgical techniques.

Collectively, these studies underscore the potential of sacral nerve reconstruction for enhancing postoperative limb function. However, the variability in outcomes emphasizes the critical role of patient selection, surgical expertise, and specific surgical techniques. Our case supports this evidence by demonstrating that meticulous surgical planning and execution can lead to favorable long-term functional outcomes following sacral nerve reconstruction. Notably, our patient exhibited no recurrence over an eight years without adjuvant therapies, highlighting the effectiveness of en bloc resection combined with sacral nerve reconstruction for achieving oncological control and functional preservation.

Limitations of our approach include the need for advanced microsurgical expertise and resources, which may not be universally available. Additionally, further research is needed to establish standardized protocols and assess the generalizability of long-term outcomes following sacral nerve reconstruction.

4. Conclusion

In conclusion, while en bloc resection with sacral nerve preservation offers promising functional outcomes and recurrence rates, careful consideration of surgical challenges and the need for specialized care is essential. Further studies are warranted to validate this approach and explore the integration of surgical and adjuvant therapies in sacral GCTB management.

Consent

Written informed consent was obtained from the patient for publication and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal on request.

Ethical approval

The data used in this case report has been obtained with the informed consent of the patient and their family. It was exempt from ethical approval by the Ethics Committee of our hospital.

Funding

None of the enlisted authors received any kind of financial assistance from any source.

Author contribution

Dong Hu collected medical records and drafted this paper. Songhua Xiao and Fei Song did the operation and revised this paper.

Guarantor

Songhua Xiao.

Declaration of competing interest

All authors declare that there is no conflict of interest that exists.