Edit concept Question Editor Create issue ticket

Retroperitoneal Neoplasm

Retroperitoneal neoplasms include benign and malignant tumors that emerge within the retroperitoneum. These are rarely encountered in the clinical practice. Lymphoma is by far the most important malignant retroperitoneal neoplasm, followed by liposarcoma, leiomyosarcoma and malignant fibrous histiocytoma, whereas a number of benign lesions are described in the literature. Symptoms in the form of abdominal pain, a palpable abdominal mass and distension, usually appear when the tumor is very large. Computed tomography (CT) and magnetic resonance imaging (MRI) are used to make the diagnosis.


Retroperitoneal neoplasms encompass tumors of different origins and nature (benign or malignant) that arise within this anatomical structure, but outside of the organs situated in the retroperitoneum [1] [2] [3] [4]. Some of the most important retroperitoneal neoplasms are [5] [6]:

The clinical course of a retroperitoneal neoplasm is predominantly described as insidious, mainly because the tumor needs to grow considerably in size before producing symptoms [2] [4] [5]. Main complaints, when present, are abdominal pain, distension, and a palpable abdominal mass, while early satiety, abdominal swelling, and gastrointestinal/urinary symptoms, which were thought to be rare, are seen in up to 40-50% of cases [2] [3] [4] [5].

Soft Tissue Mass
  • Rarely, thrombosis of an anomalous retroperitoneal vein may resemble a soft tissue mass. Awareness of this fact helps preventing unnecessary interventions.[ncbi.nlm.nih.gov]
  • The neoplasm must be considered in the differential diagnosis of pelvic and retroperitoneal soft tissue mass despite its relative rarity as compared with other retroperitoneal masses of mesenchymal origin (liposarcoma, malignant fibrous histocytioma or[ijri.org]
  • No discrete soft tissue mass is evident. Contrast-enhanced CT reveals no enhancement in pelvic lipomatosis. Magnetic Resonance Imaging Pelvic lipomatosis manifests with signal intensity of fat on T1- and T2-weighted images.[radiologykey.com]
  • MR imaging of soft-tissue masses of the extraperitoneal spaces. RadioGraphics 2001 ; 21:1141-1154. Link , Google Scholar 11 Otal P, Mezghani S, Hassissene S, et al. Imaging of retroperitoneal ganglioneuroma. Eur Radiol 2001 ; 11:940-945.[pubs.rsna.org]
  • For this reason, the physician plays a crucial role when obtaining a detailed patient history and performing a thorough clinical examination.[symptoma.com]
  • The need of strict bed rest is assessed by a physician based on the risk of increased neurological deficits and the degree of pain.[oncolex.org]
  • Rest during the day by relaxing in a good chair, but try not to fall asleep. Speak to your doctor about lasting sleep disturbances. Nutrition Having a reduced appetite or intake of food can also result in a lack of strength and energy.[oncolex.org]
Acute Abdomen
  • abdomen and new material on CT and MR angiography, lung cancer screening, pulmonary embolism, coronary artery calcium screening, and interventional CT techniques including radiofrequency ablation and CT fluoroscopy.[books.google.com]
  • Anomalies of the inferior vena cava (IVC) have been recognized as one of the predisposing factors for deep vein thrombosis. Rarely, thrombosis of an anomalous retroperitoneal vein may resemble a soft tissue mass.[ncbi.nlm.nih.gov]
  • Patients at high risk of venous thrombosis should also have subcutaneous thrombosis prophylaxis with low molecular weight heparin.[oncolex.org]
  • -29: 0.0 % 30-39: 0.0 % 40-49: 0.0 % 50-59: 0.0 % 60 : 100 % Top other side effects for these people *: Prostatitis (inflammation of the prostate gland): 2 people, 100.00% Pancreatitis Acute (sudden inflammation of pancreas): 2 people, 100.00% Gouty Arthritis[ehealthme.com]
  • […] from atherosclerotic plaques § Leads to a vasculitis o Also found in association with other fibrosing diseases suggesting auto-immune mechanism § Primary biliary cirrhosis § Fibrosing mediastinitis § Glomerulonephritis § Panhypopituitarism § Rheumatoid arthritis[learningradiology.com]


Because of a rather nonspecific (or even absent) clinical presentation, the diagnosis of a retroperitoneal neoplasm may be difficult to make. For this reason, the physician plays a crucial role when obtaining a detailed patient history and performing a thorough clinical examination. To identify the exact location of the tumor and determine its subtype, however, imaging studies need to be carried out. CT and MRI are the two main exams used in the assessment of the retroperitoneum [1] [3] [4] [5] [6]. Several findings that point to a retroperitoneal neoplasm are embedded organ sign (compression of the adjacent organ into a crescent shape), prominent feeding artery sign (hypervascularization of the presenting mass), and the presence of dull edges of the organ adjacent to the tumor [1]. Tumor types may be further discriminated by their distinguishing features:

  • Liposarcoma - High signal intensity on T1-weighted studies, intermediate T2-weighted signal, and complete loss of fat signal intensity on MR images that suppress the fatty tissue [3].
  • Leiomyosarcoma - Intermediate-to-low signal intensity on T1 and intermediate-to-high on T2 is typical, depending on the extent of necrosis [3].
  • Malignant fibrous histiocytoma - A large-infiltrating and heterogeneous necrotic and hemorrhagic mass [3].
  • Lymphoma - A well-defined homogeneous lump that mechanically compresses the major blood vessels [3].
  • Schwannomas - Well-defined cystic masses with smooth margins [5].
Ovarian Mass
  • Huge primary retroperitoneal mucinous cystadenoma of borderline malignancy mimicking an ovarian mass: case report and review. Anticancer Res 2008;28:2309-15. [ PubMed ] Behr C, Hesketh A, Soffer S, et al.[jgo.amegroups.com]


  • Treatment and prognosis Prognosis depends on the histological type of a tumor and the potential for resection.[radiopaedia.org]
  • A literature review using PubMed is also presented, discussing several issues concerning clinicopathologic features, treatment options, and long-term outcome of PRMCN.[ingentaconnect.com]
  • Chemotherapy is often one of the treatment modalities for metastatic testicular germ cell tumors.[jgo.amegroups.com]
  • DISCLAIMER: All material available on eHealthMe.com is for informational purposes only, and is not a substitute for medical advice, diagnosis, or treatment provided by a qualified healthcare provider.[ehealthme.com]
  • They will support you throughout your treatment to ensure you get the right treatment as and when you need it. Types of treatment The treatment for retroperitoneal sarcoma is highly individualised and depends on the size and location of your tumour.[sarcoma.org.uk]


  • Treatment and prognosis Prognosis depends on the histological type of a tumor and the potential for resection.[radiopaedia.org]
  • Long-term follow-up is lacking, although it is important to better define the prognosis of PRMCN. No Reference information available - sign in for access. No Citation information available - sign in for access. No Supplementary Data.[ingentaconnect.com]
  • Prognosis is affected by age and site. Those under two years and those with pelvic tumors have a better prognosis. Overall prognosis is poor. 2.[urologyweb.com]
  • Among liposarcomas, the presence of features of the dedifferentiated variant strongly portends a worse prognosis.[wjso.biomedcentral.com]
  • Peritoneal Cancer Prognosis: What to Expect Primary peritoneal cancer prognosis is best if all cancer is removed and a gynecologic surgeon and oncologist treat you. These doctors have special knowledge of gynecologic cancers.[webmd.com]


  • […] neoplasms arise from outside the major organs, and are divided according to histological types: mesenchymal origin : skeletal muscle, fat, peripheral nerve, vessels, fibrous tissue extragonadal germ cell tumors primary retroperitoneal adenocarcinoma Etiology[radiopaedia.org]
  • In most patients (approximately 68%), no etiologic factor is found. Therefore, the term idiopathic RFP is used.[emedicine.medscape.com]
  • Haworth Medical Press General According to etiology, there are two general classifications of lymphedema primary and secondary lymphedema. Primary lymphedema is caused by deficient or faulty development of the lymph system.[oncolex.org]


  • […] of Surgical Oncology, Mount Sinai Hospital and Princess Margaret Cancer Center, Department of Surgery, University of Toronto, Toronto, Canada. 2 Department of Surgery, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy. 3 Unit of Clinical Epidemiology[ncbi.nlm.nih.gov]
  • Definition / general Smooth muscle tumor with atypia plus either mitotic activity, tumor cell necrosis or size 10 cm 10% of adult soft tissue sarcomas Variants are described separately above Epidemiology Skin / subcutis: see cutaneous variants above;[pathologyoutlines.com]
  • Soft tissue sarcoma across the age spectrum: a population-based study from the Surveillance Epidemiology and End Results database. Pediatr Blood Cancer. 2011 Dec;57(6):943–9. Karadayi K, Yildiz C, Karakus S, Kurt A, Bozkurt B, Soylu S et al.[karger.com]
Sex distribution
Age distribution


  • Awareness of this fact helps preventing unnecessary interventions. We report a case of thrombosis of retroaortic left renal vein and interrupted IVC that mimicked a retroperitoneal neoplasm.[ncbi.nlm.nih.gov]
  • Click here to view the NCCN Guidelines Panel Members individual disclosures NCCN Guidelines for Treatment of Cancer by Site NCCN Guidelines for Detection, Prevention, & Risk Reduction NCCN Guidelines for Supportive Care NCCN Guidelines for Age Related[nccn.org]
  • NIH: National Cancer Institute Cancer (Medical Encyclopedia) Cancer and lymph nodes (Medical Encyclopedia) Cancer treatment -- early menopause (Medical Encyclopedia) Cancer treatment: preventing infection (Medical Encyclopedia) Cancer treatments (Medical[icdlist.com]
  • Goal Prevention and treatment of nausea and vomiting.[oncolex.org]



  1. Nishino M, Hayakawa K, Minami M, Yamamoto A, Ueda H, Takasu K. Primary retroperitoneal neoplasms: CT and MR imaging findings with anatomic and pathologic diagnostic clues. Radiographics. 2003;23(1):45-57.
  2. Brennan C, Kajal D, Khalili K, Ghai S. Solid malignant retroperitoneal masses—a pictorial review. Insights into Imaging. 2014;5(1):53-65.
  3. Rajiah P, Sinha R, Cuevas C, Dubinsky TJ, Bush WH Jr, Kolokythas O. Imaging of uncommon retroperitoneal masses. Radiographics. 2011;31:949–976.
  4. Strauss DC, Hayes AJ, Thomas JM. Retroperitoneal tumours: review of management. Ann R Coll Surg Engl. 2011;93(4):275-280.
  5. Wee-Stekly W-W, Mueller MD. Retroperitoneal Tumors in the Pelvis: A Diagnostic Challenge in Gynecology. Front Surg. 2014;1:49.
  6. Gemici K, Buldu İ, Acar T, et al. Management of patients with retroperitoneal tumors and a review of the literature. World J Surg Oncol. 2015;13:143.

Ask Question

5000 Characters left Format the text using: # Heading, **bold**, _italic_. HTML code is not allowed.
By publishing this question you agree to the TOS and Privacy policy.
• Use a precise title for your question.
• Ask a specific question and provide age, sex, symptoms, type and duration of treatment.
• Respect your own and other people's privacy, never post full names or contact information.
• Inappropriate questions will be deleted.
• In urgent cases contact a physician, visit a hospital or call an emergency service!
Last updated: 2019-06-28 10:22