Idiopathic benign retroperitoneal cyst: a case report
© Alzaraa et al; licensee BioMed Central Ltd. 2008
Received: 02 October 2007
Accepted: 08 February 2008
Published: 08 February 2008
Retroperitoneal cysts are uncommon, with an estimated incidence of 1/5750 to 1/250,000.
A male patient was admitted with an abdominal pain, jaundice and fever. Clinical examination and investigations confirmed an idiopathic benign retroperitoneal cyst. He underwent surgery and was discharged after making good recovery.
Retroperitoneal cysts are very rare, and most of the time they are discovered incidentally. Patients may be asymptomatic or present with abdominal pain, referred pain to the legs or weight loss. Imaging may help diagnose these lesions, but surgery is the keystone in confirming the diagnosis. This case is very rare and very educational as it highlights an unusual presentation of a benign retroperitoneal cyst. In our patient, the course of the disease was unique as the patient presented with jaundice.
Retroperitoneal cysts (RPCs) are uncommon with an estimated incidence of 1/5750 to 1/250,000 . Approximately one third of patients with retroperitoneal cysts are asymptomatic and the cyst is found incidentally. The cyst can grow to a considerable size before becoming symptomatic. CT scan might help in confirming the diagnosis, and surgery remains the best treatment option.
A 51 year-old man was admitted on the surgical ward in November 2003 for a right-sided abdominal pain which had been present for three days. Clinically, he was jaundiced with a high temperature. Blood tests showed white cell count (20.8 × 103/mm3), bilirubin (103 mg/dl) and ESR (75 mm/h). All other blood tests were normal. Ultrasound and CT scans of the abdomen revealed fluid collection/mass measuring 14 cm in the right hepato-renal space. The mass was separated from the liver, pancreas and the right kidney, but there was lack of definition of the right suprarenal gland. Because the patient was jaundiced, we thought that draining the cyst would relieve the pressure on the biliary system and resolve jaundice. About 150 ml brown-coloured fluid was aspirated from the mass under CT guidance and a sample was sent for histology. Cytological examination of the sample reported presence of amorphous material with occasional histiocytic cells. There was no evidence of malignancy. The patient was discharged in December 2003 after making good recovery.
Macroscopical examination of the specimen reported an open cyst measuring 190 mm × 110 mm × 0.5 mm. The outer surface was pale-dark brown with an irregular defect measuring 1.8 cm × 1.5 cm in one area. Another area showed an adrenal tissue measuring 3.0 cm × 1.0 cm × 0.5 cm with yellow areas on the surface of the cyst wall. The inner area of the cyst wall was wrinkled with an exudate-like substance coating it in places.
Differential diagnoses of retroperitoneal cysts.
There are no pathognomonic signs or symptoms for RPCs, and in approximately one third of patients, the cyst is found incidentally [3, 5]. Two thirds of patients present with an abdominal mass or chronic abdominal symptoms, most of them are omental in origin . Other symptoms include back pain, referred pain to the lower limbs, oedema of the lower limbs, weight loss or fever [6, 7]. The mass tend to be mobile in a transverse plane, or in all directions when the cyst is omental. More commonly, only a soft tissue mass with displacement of the bowel is seen .
CT is ideal for assessing RPCs because it provides discrete sectional images of the organs and retoperitoneal compartments, and in some case, familiarity with the most relevant radiologic features, in combination with clinical information, allows adequate lesion characterization . Mullerian cyst, for example, manifest as a unilocular or multilocular thin-walled cyst containing clear fluid, and clinical history may help differentiate it from other retroperitoneal masses as it is more common in obese patients with menstrual irregularities . A mature teratoma manifests as a complex mass containing a well-circumscribed fluid component, adipose tissue, and calcification. The presence of hypoattenuating fat within the cyst is considered highly suggestive of this cyst. The CT appearance of a retroperitoneal haematoma depends on the time elapsed between the traumatic event and imaging. Acute or subacute haematoma has a higher attenuation value than pure fluid due to clot formation. However, chronic haematoma has decreased attenuation because of the breakdown of blood products . Cystic lymphangioma typically appears as a large, thin-walled, multiseptate cystic mass. Its attenuation values vary from that of fluid to that of fat. An elongated shape and a crossing from one retroperitoneal compartment to an adjacent one are characteristic of the mass, and calcification of the wall is rare .
Symptomatic cysts should be enucleated or excised, while preserving the surrounding vital structures. At times, the cyst can be marsupialised or drained if surgical enucleation is difficult or the cyst is infected . However, draining the cyst usually result in a recurrence. In the analysis of the 162 patients who had mesenteric and RPCs, Kurtz R, et al  concluded that patients with RPCs were more likely to have incomplete excision of the cyst and therefore had a higher incidence of recurrence. They also required marsupialisation more often. Our patient should have had the cyst excised in the first place regardless of being jaundiced or not. Unfortunately, its pathogenesis was not known as the cyst did not have any epithelial lining.
Cysts arising within the retroperitoneum outside the major organs within that compartment are very rare. Approximately one third of patients with retroperitoneal cysts are asymptomatic and the cyst is found incidentally. CT may help diagnose these lesions, but surgery remains the keystone in determining the diagnosis.
- Guile M, Fagan M, Simopolous A, Ellerkman M: Retroperitoneal Cyst of Mullerian Origin: A case report and review of the literature. J of Pelvic Medicine and Surgery. 2007, 13 (3): 149-152. 10.1097/SPV.0b013e3180622272.View ArticleGoogle Scholar
- Handfield-Jones R: Retroperitoneal Cysts: Their Pathology, Diagnosis and Treatment. BJS. 1942, 119-134.Google Scholar
- Felix Edward, Wood Donald, Das Gupta Tapas: Tumours of the Retroperitoneun. Cancer. 1981, 6 (1): 1-47.Google Scholar
- Yang D, Jung D, Kim H, Kang H, Kim S, Kim J, Hwang H: Retroperitoneal cystic masses: CT, Clinical and Pathological Findings and Literature Review. RG. 2004, 25 (5): 1353-1365.View ArticleGoogle Scholar
- Kurtz R, Heimann T, Beck R, Holt J: Mesenteric and Retroperitoneal Cysts. Ann Surg. 1986, 203 (1): 109-112. 10.1097/00000658-198601000-00017.View ArticlePubMedPubMed CentralGoogle Scholar
- Haysaka Kazumasa, Yamada Tomonori, Saitoh Yasuhiro, Yoshikawa Daihei: CT Evaluation of Primary Benign Retropeitoneal Tumour. Diagnostic Radiology. 1994, 12 (3): 115-120.Google Scholar
- Konishi Eiichi, Nakashima Yasuaki, Iwasaki Takeki: Immunohistochemical analysis of Retroperitoneal Mullerian Cyst. Human Pathology. 2003, 34 (2): 194-198. 10.1053/hupa.2003.12.View ArticlePubMedGoogle Scholar
- Ravo B, Metwally N, Pai B, Ger R: Developmental retroperitoneal Cysts of the Pelvis; A Review. Dis Col & Rect. 1987, 30 (7): 559-564. 10.1007/BF02554791.View ArticleGoogle Scholar
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.