A case of a giant thoracic schwannoma.

Background: Giant solitary schwannomas are rare, benign, and typically slow-growing tumors reaching up to 20 cm in size. Case Description: A 43-year-old male presented with shortness of breath and chest pain. The thoracic MRI showed a giant mass 15 cm in diameter filling the left chest cavity. The lesion was resected utilizing intrathoracic approach and required a multilevel approach. Vertebrectomy with instrumented fusion was performed. The pathological diagnosis was benign schwannoma without nuclear atypia. Postoperatively, the patient fully recovered without sequelae.
Conclusion: A 43-year-old male presented with a 15 cm diameter chest mass that proved to be a schwannoma that was resected without long-term sequelae. Copyright:

INTRODUCTION

Spinal schwannomas are slow-growing benign tumors.[4] Although often completely intradural, 30% extend through the dural root sleeve exhibiting both intradural and extradural features. Giant invasive spinal schwannomas are typically described as involving more than 2 vertebral levels with extraspinal extension of more than 2.5 cm. Other features may include vertebral body erosion and posterior and lateral extension into myofascial planes. Notably, for lesions more than 5 cm in diameter, heterogeneity and indistinct margins without a pseudo-capsule may indicate malignant transformation.[7] Here, we report a 43-year-old male who presented with a benign 15 cm diameter left chest schwannoma that was readily resected, resulting in no long-term sequelae.

CASE REPORT

A 43-year-old male presented with shortness of breath, bilateral upper limb tingling, and chest pain. The chest x-ray [Figure 1] and thoracic MR scan showed a massive left-sided tumor at the T6 that extended through the T6/T7 foramen and ballooned in the chest cavity measuring 10 cm × 15 cm × 12 cm in diameter [Figure 2]. There was a concern that the tumor was malignant due to its large size and variegated appearance. Surgery included a combined spinal (vertebrectomy)/intrathoracic resection of a giant thoracic schwannoma plus an instrumented fusion performed. Of interest, the patient required massive blood transfusion due to highly vascular tumor capsule and adhesions to the lung. The patient developed infective collection (empyema) after surgery and was admitted to intensive care for 1 week. The histopathology confirmed that the lesion was a benign schwannoma with some degenerative nuclear atypia but no frank malignant features. The postoperative MRI documented gross total resection of the prior intrathoracic/left T6-T7 foraminal/spinal tumor mass [Figure 3]. When the patient developed a left-sided empyema, drained under ultrasound guidance, IV antibiotics were appropriately administered and adequately managed.

Figure 1:

(a) Preoperative chest X-ray a 16 cm soft-tissue mass within the left lung and (b) postoperative chest X-ray AP view.

Figure 2:

Preoperative MRI a massive left-sided chest tumor which measures approximately 10 × 15 × 12 cm in diameter with solid and metacystic appearance, there is an intraspinal component of this tumor which enters the spinal canal at the T6-7 level. (a) Coronal section T2, (b) sagittal section T2, and (c) axial section T2.

Figure 3:

Postoperative MRI, there is no definable residual tumor with normal spinal canal (a) sagittal section, (b) axial section, and (c) coronal section.

DISCUSSION

Rare giant solitary schwannomas

Giant solitary schwannomas are rare benign tumors that typically involve more than 2 vertebral levels and can range from a few millimeters to more than 20 cm.[6]

In a study of 303 benign solitary schwannomas, Das Gupta et al. found 10 patients with lesions between 10 and 15 cm in maximum diameter; only two were over 20 cm in diameter [Table 1].[2]

Table 1:

Benign schwannoma variation in tumor size in a study of 303 cases, Das Gupta et al.

Intraspinal schwannoma with foraminal extension into the chest typically arises from the intercostal and sympathetic nerves, but only rarely presents as predominantly intrapulmonary masses.[3,6]

CT and MR studies of thoracic schwannomas

Studies of large/giant schwannomas have typical features on CT and MR studies [Table 2]. On CT, these lesions are usually low density and show modest enhancement with punctate calcification. On MR, they are hypodense lesions on T1- and hyperdense lesions on in T2-weighted images that markedly enhance with contrast. Although huge schwannomas raise concerns about malignancy, they are usually benign. However, they often warrant surgical intervention due to their mass effect.[1] Our case illustrates that even these kinds of massive tumors (supergiant schwannomas, more than 10 cm in size) can be benign and if faced with a similar case again, we probably would not choose to remove the vertebra and instrument.

Table 2:

Summary of giant schwannoma cases reported.

CONCLUSION

Here, we reported a 15 cm diameter left-sided spinal T6-t7 foraminal/intrathoracic schwannoma that was totally excised utilizing a combined intraspinal/intrathoracic approach without further long-term sequelae.