Inflammatory myofibroblastic tumour of the spleen: A diagnostic challenge

Inflammatory myofibroblastic tumour (IMT) is a rare mesenchymal neoplasm with intermediate biological behavior. Splenic IMT, first described in 1980, is an exceptionally uncommon presentation, with approximately 120 cases reported in the literature by 2021.

A 52-year-old female presented to the gastroenterology department with complaints of left hypochondrial pain. Physical examination revealed slight tenderness in the left hypochondrium. Abdominal ultrasonography showed a well-defined, heterogeneous mass measuring 42 × 58 mm. Abdominal MRI confirmed the presence of a splenic, non-encapsulated solid mass with regular contours. The patient underwent a laparoscopic-assisted splenectomy, and the microscopic examination confirmed the diagnosis of IMT.

With the available literature, there are very few splenic IMTs, and the causes for this condition are yet to be determined. There have been suggestions connecting them to Epstein-Barr virus (EBV) infection. Imaging studies are non-specific and are not helpful to differentiate between IMTs and other splenic lesions, this necessitates a pathological examination to be established as the gold standard. The treatment that is considered most effective is total surgical removal, which is often curative. Though the literature shows a good prognosis, long-term follow-up is advisable to monitor for recurrence and the possibility of reaching metastasis.

IMT of the spleen is an extremely rare tumour that often poses a diagnostic challenge. Pathological examination is the gold standard for diagnosing these lesions. This case report is intended to inform pathologists, radiologists, and clinicians about the mentioned entity's targeted characteristics to enable timely identification of the lesion.