Histopathological and Immunohistochemical Patterns of Malignant Peripheral Nerve Sheath Tumours in a Tertiary Institution of Northern Nigeria.

Background: Malignant peripheral nerve sheath tumours (MPNSTs)are uncommon, aggressive sarcomas arising from a peripheral nerve or extra neural soft tissue and show evidence of nerve sheath differentiation. These tumours exhibit variability in grade and can either occur as familial or sporadic tumours. Immunohistochemistry is a paramount tool in the evaluation of these tumours. This study aimed at analyzing the histopathological and immunohistochemical patterns of these tumours and determining the frequency, demographic and anatomical site distribution. Methodology: This was a 10-year retrospective hospital-based study. Formalin fixed paraffin embedded tissue blocks were sectioned and the slides werereviewed and interpreted. Morphological features were noted and immunohistochemical analysis was performed using four primary antibodies. Descriptive statistical analysis was used to collate and analyse data, and statistical test was used where necessary. The results were presented on statistical charts and tables. Result: In this series, 20 cases of MPNSTs were seen with a male predilection. The 3 Conclusion: Malignant peripheral nerve sheath tumours are uncommon and tend to be sporadic in our region. Most of these tumours are borderline/intermediate grade tumours (Grade 2) showing low immunoexpression to antibodies employed with varying intensities.