Abstract: IP is a rare benign proliferative lesion characterized by fibrous tissue proliferation and chronic inflammatory cell infiltration.Named for its resemblance to an aggressive malignancy in clinical presentation,imaging,and histology,its etiology is unclear and may be related to infection,immune abnormalities,or trauma.Surgical resection is the only treatment.This article reports on a 78year-old male patient with low back pain,fever and malaise as the main symptoms and a past history of tuberculosis.Surgical resection was performed after ineffective anti-inflammatory treatment.The preoperative histologic examination of the perforated mass showed inflammatory lesions,and the postoperative pathology confirmed retroperitoneal IP.The patient was followed up for the first month and the CT examination revealed recurrence of the mass at the original surgical site,and the mass was found to have become slightly smaller in the second month,and the patient is currently being followed up for the next few months.Pathology is the gold standard for diagnosis,radical surgical resection is the primary treatment,and cure can be achieved by surgical resection in the case of recurrence.

Key words: inflammatory pseudotumor, benign proliferative lesion, recurrence, surgical resection