• Clinical outcomes
• Clinical presentation
• Disc material
• Posterior epidural migration

• Humans
• Lumbar Vertebrae/surgery
• Epidural Space/surgery
• Thoracic Vertebrae/surgery
• Intervertebral Disc Displacement/surgery
• Middle Aged
• Female
• Male
• Intervertebral Disc/surgery
• Adult
• Treatment Outcome

• Disc Herniation
• MRI
• Sequestrated Disc Fragments

• Humans
• Intervertebral Disc Displacement/diagnostic imaging
• Intervertebral Disc Displacement/surgery
• Magnetic Resonance Imaging
• Diagnosis, Differential
• Adult
• Lumbar Vertebrae/diagnostic imaging
• Imaging, Three-Dimensional
• Male
• Female
• Spinal Neoplasms/diagnostic imaging
• Spinal Neoplasms/surgery

• magnetic resonance imaging
• mimicking tumor discs
• reliability
• schwannoma
• sensitivity

• Humans
• Female
• Adult
• Middle Aged
• Aged
• Diagnosis, Differential
• Retrospective Studies
• Water
• Reproducibility of Results
• Neoplasms
• Magnetic Resonance Imaging

• National Natural Science Foundation of China

Disc herniation refers to the displacement of disc material beyond its anatomical space. Disc sequestration is defined as migration of the herniated disc fragment into the epidural space, completely separating it from the parent disc. The fragment can move in upward, inferior, and lateral directions, which often causes low back pain and discomfort, abnormal sensation, and movement of lower limbs. The free disc fragments detached from the parent disc often mimic spinal tumors. Tumor like lumbar disc herniation can cause clinical symptoms similar to spinal tumors, such as lumbar soreness, pain, numbness and weakness of lower limbs, radiation pain of lower limbs, etc. It is usually necessary to diagnose the disease according to the doctor's clinical experience, and make preliminary diagnosis and differential diagnosis with the help of magnetic resonance imaging (MRI) and contrast-enhanced MRI. However, pathological examination is the gold standard that distinguishes tumoral from non-tumoral status. We report four cases of disc herniation mimicking a tumor, and all the pathological results were intervertebral disc tissue.

The first case was a 71-year-old man with low back pain accompanied by left lower extremity radiating pain for 1 year, with exacerbation over the last 2 wk. After admission, MRI revealed a circular T2-hypointense lesion in the spinal canal of the L4 vertebral segment, with enhancement on contrast-enhanced MRI suggesting neurilemmoma. The second case was a 74-year-old man with pain in both knees associated with movement limitation for 3 years, with exacerbation over the last 3 mo. MRI revealed an oval T2-hyperintense lesion in the spinal canal at the L4–5 level, with obvious peripheral enhancement on contrast-enhanced MRI. Thus, neurilemmoma was suspected. The third case was a 53-year-old man who presented with numbness and weakness of the lumbar spine and right lower extremity for 2 wk. MRI revealed a round T2-hyperintense lesion in the spinal canal at the L4–5 level, with obvious rim enhancement on contrast-enhanced MRI. Thus, a spinal tumor was suspected. The fourth case was a 75-year-old man with right lower extremity pain for 2 wk, with exacerbation over the last week. MRI revealed a round T1-isointense lesion in the spinal canal of the L3 vertebral segment and a T2-hyperintense signal from the lesion. There was no obvious enhancement on contrast-enhanced MRI, so a spinal tumor was suspected. All four patients underwent surgery and recovered to ASIA grade E on postoperative days 5, 8, 8, and 6, respectively. All patients had an uneventful postoperative course and fully recovered within 3 mo.

Disc herniation mimicking a tumor is a relatively rare clinical entity and can be easily misdiagnosed as a spinal tumor. Examinations and tests should be improved preoperatively. Patients should undergo comprehensive preoperative evaluations, and the lesions should be removed surgically and confirmed by pathological diagnosis.

• Disc herniation
• Disc sequestration
• Mimicking tumor
• Spinal tumor
• Surgery
• Case reports

Sequestered disc fragments do not have indistinctive features and often share the clinical and radiological presentation as spinal neoplasms making their diagnosis and treatment a clinical challenge.

We report a rare case of sequestered lumbar disc fragment at the level of L2-L3 in a 70-year-old male who presented to the ER complaining of six years' history of low back pain with acute onset lower extremities weakness for six days, associated with right foot drop. He was admitted for tumor workup as the MRI showed diffuse bone high signal intensity throughout the spine with a soft tissue epidural mass at L2/3, causing severe compression on the cauda equina nerve roots. The patient underwent L2-L3 decompression and fixation, mass excision, multiple open biopsies. Soft tissue biopsy of the mass revealed fibrocartilaginous tissue consistent with the intervertebral disc, while the bone biopsy was diagnostic of acute leukemia. The patient was observed postoperatively with unremarkable complications. He did well with physiotherapy, and there was a remarkable improvement of his right lower extremity power reaching 4/5.

Our case presented a rare phenomenon in which sequestered disc fragments manifested clinically and radiologically as a spinal neoplasm. Vigilant history taking and physical examination are paramount; a physician should be watchful for any red flags that may warrant further investigation such as in our case.

• herniated
• lumbar disc
• mimicking
• neoplasm
• sequestrated

Since disc sequestration that mimics a tumor is rare and sometimes presents with an atypical appearance upon magnetic resonance imaging (MRI), it is often confused with other more common epidural and intradural neoplasms, particularly neurinoma. Open surgery is necessary due to the difficult of achieving a definitive diagnosis using computed tomography, MRI, and gadolinium- enhanced MRI prior to operation. Herein, we describe the use of coronal MR images of 3D fast-field echo with water selective excitation in the diagnosis of disc sequestration mimicking a tumor.

Two patients were admitted to our hospital with back pain, radiating pain, and hypoesthesia in the right lower limb. MRI revealed tumor-like masses in the lateral recess of L3 and posterior to the body of L4. The initial diagnosis indicated disc sequestration mimicking a tumor and neurinoma. The coronal MR images of 3D fast-field echo with water selective excitation showed a clear boundary between the tumor-like mass and the nerve root. Moreover, the mass was also completely separated from the dura. Therefore, neurinoma was excluded as a possible diagnosis prior to operation. Surgical excision to perform removal of the gross mass was performed in one patient. The histopathological diagnosis was consistent with the 3D fast-field echo with water-selective excitation MRI. Another patient was successfully treated by minimally invasive endoscopic surgery.

Disc sequestration that mimics a tumor is difficult to diagnose preoperatively. As a non–invasive strategy, coronal MR images of 3D fast-field echo with water selective excitation is a helpful imaging tool for differentiating between diagnosis of disc sequestration that mimics a tumor and neurinoma prior to operation. If the disc fragment of mimicking tumor can be identified prior to operation, open surgery may not be necessary for all patients. Minimally invasive endoscopic surgery also is an alternative strategy.

• 3D fast-field echo with water selective excitation
• Disc sequestration
• Lumbar disc herniation
• Mimicking tumor