Extracranial schwannomas of peripheral nervous system: An aesthetic challenge - A comprehensive analysis of 38 cases

Schwannomas are benign, slow-growing tumours that arise from Schwann cells. Extracranial schwannomas are less common than those occurring at the intracranial vestibulocochlear and cerebellopontine angles. Because extracranial schwannomas are uncommon, it is difficult to make an accurate clinical diagnosis. Therefore, histopathological examination is the gold standard.

In this study, we aim to describe the incidence, presenting clinical features, anatomical location, size, and initial (presumption) diagnosis of thirty-eight cases that were histopathologically diagnosed as extracranial schwannomas, along with a literature review. A retrospective, cross-sectional observational study was conducted at the Department of Pathology and Laboratory Medicine, All India Institute of Medical Science, Rishikesh, India, from January 2018 to June 2024. Data and histopathological slides were retrieved and analysed.

Thirty-eight patients were documented, with an age range of 11-75 years and a mean age of 37 years, and a male predominance (M:F, 2.8:1) was noted. Tumour size ranged from 0.3 to 13cm. Thirteen cases of schwannomas occurred in the head and neck (34.21%), eleven in the spine (29%), six in the upper extremities (15.79%), three each in the lower extremities (7.88%) and the upper trunk (7.88%) and two in the lower trunk/visceral region (5.24%). Most patients presented with painless swellings. The study indicates that schwannomas were most commonly found in the head and neck region, followed by the spine. Within the extremities, they were more frequent in the upper extremities, while in the trunk, they were found in the chest wall, ribs, posterior mediastinum (part of the chest cavity), adrenal gland, and pararenal area.

The study indicates that schwannomas are most commonly found in the head and neck region, followed by the spine. Within the extremities, they occur more frequently in the upper extremities, while in the trunk they were found in the chest wall, ribs, posterior mediastinum (part of the chest cavity), adrenal gland, and pararenal area. The radioresistant nature of schwannomas alerts both clinicians and pathologists to the importance of early diagnosis and to be familiar with their uncommon anatomical locations.