Patients with retroperitoneal sarcoma can present to a variety of clinicians with non-specific symptoms and retroperitoneal sarcomas can be incidental findings. Failure to recognize retroperitoneal sarcomas on imaging can lead to inappropriate management in non-specialist centers. Therefore it is critical that the possibility of retroperitoneal sarcoma should be considered with prompt referral ...

Congenital teratomas occur in extragonadal locations, the commonest site being the sacrococcygeal region. This report describes a rare case of antenatally detected, large, immature retroperitoneal teratoma. The diagnostic and therapeutic challenges of dealing with such a case have been discussed and the relevant literature reviewed. The recurrence of the tumor after gross surgical removal indic...

The first report in the world literature of the condition which is now generally known as idiopathic retroperitoneal fibrosis was that of Albarran (1905), but the first report in the English language did not appear until that of Ormond (1948). Since then many further case reports have been published, but the aetiology of the condition remains obscure. The disease usually presents as a urologica...

Extrarenal angiomyolipomas (ERAMLs) are rare tumors that present as incidentalomas upon imaging for other conditions. Retroperitoneal ERAMLs present a unique challenge from a diagnostic and treatment standpoint as they can mimic other benign and malignant retroperitoneal tumors. We present a case of a 39-year-old female with a 19.3 cm × 13.5 cm × 10.7 cm left extrarenal retroperitoneal mass. Hi...

Soft tissue sarcomas represent less than 1% of all human neoplasms. One-third of malignant tumors that arise in the retroperitoneum are sarcomas and liposarcoma is the most common retroperitoneal sarcoma. More often than not, patients report late to the hospital due to the slow progress and few late symptoms. Thus, the tumor is known to grow to enormous sizes. Here, we report a case of giant re...

Perivascular epithelioid cell tumor (PEComa) is an extremely rare neoplasm that appears to arise most commonly at visceral (especially gastrointestinal and uterine), retroperitoneal, and abdominopelvic sites. Malignant PEComas exist but are very rare. These tumors represent a family of mesenchymal neoplasms, mechanistically linked through activation of the mTOR signaling pathway. Metastatic PEC...

We report a rare case of Erdheim-Chester Disease, a non-Langerhans cell histiocytosis. A 60-year old female presented with a seven-month history of vague abdominal symptoms. A large retroperitoneal mass was detected on computed tomography (CT), but multiple CT-guided biopsy samples were inconclusive. Laparoscopy revealed a mass in the distal ileum, which was resected. Histology and immuno-histo...

Retroperitoneal fibrosis in a 12-year-old boy is reported. This was associated with a fibrotic mass in the neck which resolved spontaneously. Right-sided ureteric obstruction responded to treatment with steroids.

Primary mesenteric liposarcoma is a rare malignant tumour of mesenchymal origin. Under the MeSH classification, mesenteric liposarcoma appears to be classified with retroperitoneal neoplasms. Two synchronous mesenteric liposarcomas must be very unusual. We report a rare case of double mesenteric liposarcoma in a 66-year-old female patient. She was treated with wide surgical resection alone with...

Renal replacement lipomatosis is a condition characterized by varying degrees of renal parenchymal atrophy and perirenal fibrofatty proliferation secondary to chronic inflammation such as xanthogranulomatous pyelonephritis. In severe cases, imaging findings can be misdiagnosed as retroperitoneal liposarcoma.