Oversized primary intrapulmonary schwannoma: A case report and a review of the literature

Abstract

Background: Schwannomas, also known as neurilemommas, are benign, well-circumscribed encapsulated peripheral nerve sheath tumors with rather indolent evolution. Made up of cells closely related to normal myelinating Schwann cells, these neoplasms may arise from the peripheral nervous system as well as from spinal or cranial nerves. They are mostly found in the base of the skull, neck, chest wall, posterior mediastinum, posterior spinal roots, cerebellopontine angle, retroperitoneum, and flexor surfaces of the extremities. The incidence rate of spinal schwannoma is 0.3-0.5/100,000 cases per year with an average age of 50 at diagnosis. We report a case of intrapulmonary schwannoma, adding a review of the literature. Case Description: A 20-year-old female patient with no significant medical history, presented with pleuritic chest pain, shortness of breath, right upper limb weakness, and numbness. A computed tomography of the chest and magnetic resonance imaging showed a 7.2 × 10.5 × 8.3 cm mass in the posterior segment of the right upper lobe, arising from the right T5-6 neural foramen; a concurrent 16 mm thick right pleural effusion was also noticed yet without evidence of nodular enhancement. The findings suggested the presence of a neurofibroma or a schwannoma. Complete resection of the tumor was achieved through posterolateral thoracotomy; the ensuing histopathological and immunohistochemical examinations confirmed the presence of a schwannoma. Conclusion: We believe this rare case of pulmonary invasive schwannoma illustrates the complex dynamics of this extremely rare entity; in this particular case, complete surgical excision proved to be crucial in terms of subacute management and local tumor control, at least at short and middle term. The patient is currently asymptomatic (6 months postsurgery) and remains on follow-up.