Schwannoma of the Upper Limb: Retrospective Study of a Rare Tumor with Uncommon Locations

Abstract

Background: Although schwannoma (neurilemmoma) is the most common tumor of the peripheral nerve, its low incidence, slow growth and vague symptoms often lead to misdiagnosis or delayed diagnosis. The aim of the study is to present a series with a large number of schwannomas in the upper limbs, some with very rare occurrence. Methods: We report 17 patients with a mean age of 58.5 years and upper limb schwannomas, located on the median, ulnar and radial nerves, but also on the posterior interosseous nerve and digital collateral nerves. The diagnosis was made by clinical examination and imaging tests, and in no case was a preoperative biopsy performed. Surgical treatment was established based on symptoms or aesthetic concerns. In all cases, a diagnosis of schwannoma was confirmed through histopathological and immunohistochemical examinations. Results: For all patients, a complete tumor enucleation was performed under a surgical microscope. No recurrence was recorded at 2 years after surgery. Patient satisfaction was good, with complete socio-professional integration in all cases. Conclusions: Although more frequently present on the main nerve trunks, schwannoma may be present on the collateral digital nerves in rare cases. A correct technique with complete tumor excision offers excellent postoperative outcomes and avoids recurrences.

Recurrent schwannoma of digital nerve on both hands: A very rare case report

“…There is no gender preference and this lesion was reported within the age range of 30–60 years old. In our case, the patient is a 52-year-old man which is supported by the evidence of mean age reported by Pertea et al [7] (58.5 years), Majumder et al [11] (48 years), and Hirai et al [12] (56 years). This finding suggested that the older age group might have a higher risk of schwannoma occurrence.…”

“…Moreover, the presence of major neurological signs such as pain, paresthesia, and tingling sensation suggests an unfavorable post-operative outcome. In our patient, despite the history of recurrence and a long onset of growth, there were no neurological problems and the Tinel sign was negative [1] , [7] . Thus, a good prognosis can be expected.…”

“…In the T2-weighted image, schwannoma appears bright with a heterogeneous hyperintensity. A lower intensity signal at the core of the mass (bull's eye or target sign) may also be observed in schwannoma and in another peripheral nerve sheath tumor, neurofibroma [2] , [7] , [10] . In our case, the MRI findings strongly supported a peripheral nerve sheath tumor diagnosis.…”

“…In the case of the upper extremity schwannoma, the ulnar nerve is the most common nerve involved, and the median nerve is the second most commonly involved. The occurrence of this lesion on the digital nerve is extremely rare and only reported in several literatures: Troy et al [6] , Pertea et al [7] , Han KJ et al [8] , Aleksić et al [9] , and Nicolescu et al [10] .…”

“…The etiology of schwannoma is poorly understood and appears to have a chromosomal pathology that causes mutations in SMARCBI and LZTR1 which are tumor suppressors genes for Schwan cell proliferation [7] , [10] . There is no gender preference and this lesion was reported within the age range of 30–60 years old.…”