Retroperitoneum.

1. Retroperitoneum.

3. Retroperitoneal fibrosis

4. Background: The French urologist Albarran first described retroperitoneal fibrosis (RPF) in 1905, but with Ormond's publication in 1948, the disease became an established clinical entity. Ormond’s disease

5. In most patients (approx. 68%), no etiologic factor is found. Therefore, the term idiopathic RFP is used. Recent evidence suggests that RPF is an autoimmune response to an insoluble lipid called ceroid that has leaked through a thinned arterial wall from atheromatous plaques. Other implicated causes include drugs, abdominal aortic aneurysm, ureteric renal injury, infection, retroperitoneal malignancy, postirradiation therapy, and chemotherapy. No genetic predominance is seen in malignant retroperitoneal fibrosis.

6. RPF can be diagnosed on the basis of the history and the radiologic observations. At times, the diagnosis is not established firmly until surgical exploration. The use of steroids in RPF remains controversial; however, some authors believe that steroids can be used as an adjuvant to surgical ureterolysis. More recently, immunosuppressive drugs, such as azathioprine, cyclophosphamide, and tamoxifen, have been used to treat RPF.

7. RPF is relatively uncommon, with an incidence of 1 case per 200,000 population. The age range of patients is 7-85 years, with predominance in patients aged 40-60 years.

8. Clinical Details: Most patients present with nonspecific symptoms of less than 12-months' duration. Children may present with hip or gluteal pain. • In the early stage, signs and symptoms originate from the disease process; in the advanced stage, clinical features represent the effects of obstructive uropathy and renal failure. • The most common presentation is: • pain (92%) occurring in the flank (42%), the back (32%), the scrotum (8%), or the lower abdomen (28%). • Other presentations include: • fever, • weight loss (38%), • nausea and vomiting (32%), • malaise (18%), • polyuria (18%), • polydipsia (18%), • anorexia (15%), • nocturia (13%), • oliguria (10%), • urinary frequency (8%), • and hematuria (2%).

9. Hypertension is a common clinical feature. The disease has been reported to manifest as constipation and large-bowel and duodenal obstruction. Fibrotic processes can also cause compression of the great vessels, resulting in thrombophlebitis and arterial insufficiency. RPF has been documented to present as jaundice resulting from involvement of the common bile duct and exophthalmos resulting from retro-orbital disease. RPF can appear at a later stage as a complication of fibrosis. The patient may present with renal failure resulting from ureteric involvement. Venous and lymphatic obstruction may present as lower-limb edema. Claudication may result secondary to arterial insufficiency. Invasion of the duodenum and colon and the common bile duct has been documented as causing bowel obstruction and jaundice, respectively. Neurologic presentation secondary to spinal epidural extension has been reported. The diagnosis of RPF often is delayed because of its nonspecific presentation.

10. Laboratory findings: • Anemia • increased erythrocyte sedimentation rate (ESR). • Elevated white cell counts and pyuria can occur.

11. Retroperitoneal fibrosis. Plain abdominal radiograph of a patient with biopsy-proven retroperitoneal fibrosis shows a calcified mass in the retroperitoneum (to the right of the mid lumbar spine).

12. Retroperitoneal fibrosis. Excretory 5-minute urographic image demonstrates medial deviation of the right ureter at the L3-L4 vertebral level, which is suggestive of retroperitoneal fibrosis. Note the delayed excretion of the hydronephrotic left kidney. Retroperitoneal fibrosis. Excretory 15-minute urographic image (same patient as in Image 2 and obtained 1 year later) shows progression in the severity of hydronephrosis. Smooth tapering of the medially deviated ureters is noted.

13. Retroperitoneal fibrosis. CT scan in a 62-year-old man shows a soft-tissue-attenuating mass encircling the abdominal aorta. Note the extension of the soft-tissue mass around the left kidney. A right-sided nephrostomy and a left ureteric stent are seen. Retroperitoneal fibrosis. CT scan in a 62-year-old man (same patient as in first Image) shows a soft-tissue-attenuating mass encircling the common iliac arteries.

14. Retroperitoneal fibrosis. Aortic and common iliac arterial graft in a patient with severe arterial insufficiency secondary to retroperitoneal fibrosis. Note a nephrostomy catheter in the right renal collecting system and the fragmented left ureteric stent.

15. Plain radiographic findings in RPF are nonspecific, and most findings are related to the late complications of fibrosis, such as bowel obstruction and pulmonary edema secondary to renal failure. Contrast-enhanced studies, such as barium follow-through and barium enema examinations, can show the level of bowel obstruction. The diagnosis of RPF has often been suggested on the basis of the excretory urographic findings due to extensive changes in the urinary tract. Retrograde pyelography is used in patients with severely impaired renal function. Aortography, venography, and lymphangiography help in assessing the level and extent of occlusion; however, findings from these examinations can be normal in advanced disease. Ultrasonography can be used as a noninvasive technique. Sonograms may or may not help in identifying the retroperitoneal mass, but they can readily demonstrate the degree of obstruction to the ureters and kidneys. Attempts have been made to differentiate benign RPF from malignant RPF by using color Doppler imaging. Computed tomography (CT) and magnetic resonance imaging (MRI) provide superior delineation of the extent of the masses of RPF. Isotope renography is useful in the serial assessment of renal function. Gallium scintigraphy may demonstrate increased uptake, depending on the activity of inflammation. The use of 2-[fluorine 18]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) in differentiating benign from malignant RPF is promising.

16. Other Problems to be Considered: RPF must be differentiated from other conditions that can cause ureteric obstruction and renal failure, such as retroperitoneal abscess, infections, inflammation, pelvic surgery, and radiation therapy. Unusual causes that can cause ureteric obstruction include barium granuloma after colon perforation, use of sclerosing agents for treatment of inguinal hernia and hemorrhoids, and methyl methacrylate cement used for joint replacement.Imaging appearances similar to those of RPF can be demonstrated by abdominal aortic aneurysm; tumors inducing desmoplastic response, such as lymphomas, sarcomas, and pancreatic carcinomas; and metastatic malignancies from the breast, lung, stomach, colon, kidney, bladder, prostate, and cervix. Other conditions that may simulate RPF include periaortic hematoma and amyloidosis.

17. Intervention: Biopsy can be performed under CT guidance to differentiate benign masses from malignant retroperitoneal masses. Drainage of the upper urinary tract can be performed as a temporary measure. Percutaneous nephrostomy and the insertion of a double-J stent helps restore renal function and allows time to improve fluid, electrolyte, and acid-base balance prior to surgery. Treatment: The use of steroids in RPF remains controversial; however, some authors believe that steroids can be used as an adjuvant to surgical ureterolysis. More recently, immunosuppressive drugs, such as azathioprine, cyclophosphamide, and tamoxifen, have been used to treat RPF. In drug-related RPF, cessation of the drug therapy can result in restitution of the urinary tract and disappearance of the symptoms.

18. Retroperitoneal tumors

19. Primary tumors of the retroperitoneum develop independently from cells distinct from the major retroperitoneal organs such as the: pancreas, kidney, adrenal gland, major blood vessels.

20. The cause is unclear. Rarely, a history of therapeutic radiation usually more than 10 years before onset. The incidence of reported sarcomas after therapeutic radiation is low, ranging from 0.03 to 0.3 percent, with the most common type being malignant fibrous histiocytoma. Exposure to vinyl chloride, thorium dioxide, and other agents is associated with sarcomas. Several familial disorders such as Gardner's syndrome, familial retinoblastoma, neurofibromatosis, and Li- Fraumani syndrome are associated with benign and malignant soft tissue tumors. Germ-line mutations of the p53 tumor suppressor gene on chromosome 17 is present in some of these familial disorders. Retroperitoneal sarcomas are relatively rare mesenchymal and neurogenic tumors often occurring in the fifth or sixth decade of life. Despite their rarity, they should be considered in the differential diagnosis of an unknown abdominal mass.

21. The most common RP malignancies are: • sarcomas, • lymphomas, • extragonadal germ cell tumors, • and carcinomas

22. Approximately 6000 soft tissue sarcomas annually (USA), nearly 1000 of these occur in the retroperitoneum

23. Retroperitoneal tumors generally arise from mesodermal or neuroectodermal tissues or remnants of the embryonal urogenital apparatus. • Tumors may arise from: • fat, • aerolar tissue, • vascular or nervous tissue, • muscle, • fascia, • lymphatics, • nodal tissues. • Tumors of smooth muscle origin, germ cell tumors, teratomas, and other complex lesions also may occur.

24. Lymphomas and retroperitoneal sarcomas are the most common malignant lesions of the retroperitoneum

25. Define: margins, size, and histologic grade to obtain prognosis

26. The American Joint Commission on Cancer criteria distinguish three grades and tumor sizes 5 cm and less or more than 5 cm to provide prognostic criteria, but other systems use only two grades. A low grade is assigned to myxoid and well- differentiated liposarcoma and high grade to rhabdomyosarcoma, synovial sarcoma, and alveolar soft part sarcoma If metastasis occur, it typically spreads hematogenously to liver and lung. Lymph node metastases are rare ( < 5% )

27. Symptoms are produced by compression or obstruction of adjacent tissues. • an enlarging mass in the abdomen, • a vague abdominal discomfort, • a sense of fullness or heaviness. • Pain may become severe if compression of adjacent nerves or nerve plexuses occur. • Gastrointestinal stromal cell tumors (leiomyosarcomas) may result in nausea, vomiting, intestinal obstruction, and gastrointestinal bleeding. • Occasionally, fever, weakness, weight loss, and genitourinary symptoms can occur depending on the size and location of the neoplasm. • Pelvic tumors give rise to urinary frequency or rarely anuria. They also may compress pelvic veins resulting in lower extremity swelling and varicosities.

28. Lab. studies : • serum a-fetoprotein • β -human chorionic gonadotropin • should be obtained to exclude retroperitoneal germ cell tumors.

29. CT scan. Use of fast, helical CT scanners allows excellent definition of the extent of the mass, the potential involvement of vital organs or major vascular structures with the primary tumor, and the involvement of the liver, lungs, or peritoneal cavity with metastases. MRI is an excellent diagnostic tool permitting sagittal and coronal views and providing a three-dimensional image to define tumor extent and resectability. Use of contrast enhancement with gallium may be helpful to improve specificity and sensitivity of the examination. These studies can determine tumor size and whether the lesion is solid or cystic. They also are useful for planning the operative approach using abdominal, flank, or thoracoabdominal incisions. Ultrasound, gastrointestinal barium studies, and angiography (aortography) are rarely indicated except when gastrointestinal stromal tumors are suspected. If lymphoma is suspected as the cause of a retroperitoneal mass, a CT- directed needle biopsy often can be done. Fine-needle aspirates are used, but most pathologists require analysis of cells and stroma for diagnostic accuracy, requiring a percutaneous needle biopsy. The exact location of the retroperitoneal mass, its appearance, and the presence or absence of adenopathy and lymphoma (B) symptoms of fever, weight loss, and night sweats dictate whether a biopsy should be performed. Preoperative tissue diagnosis is useful only if a lesion treated nonsurgically could be determined.

30. Despite their rarity, they should be considered in the differential diagnosis of an unknown abdominal mass.

31. EUS-guided FNA smears confirmed the diagnosis of malignancy and showed clumps of atypical cells.

32. Patient diagnosed by transabdominal ultrasound with a large retroperitoneal tumor in contact with the left liver lobe. EUS allowed the visualization of the tumor from the stomach with absent power Doppler signals inside.

33. EUS-guided FNA (fine needle biopsy) smears confirmed the diagnosis of malignancy and showed clumps of atypical cells.

34. Laparoscopic ultrasound.

35. Laparoscopic ultrasound. 1: Liver 2: Delineated tumor at 3 cm. ( Leiomyoma )

36. Case report I

37. A 50-year old woman was admitted to our surgical department because of recurring, intermittent pain in the right upper quadrant of two month duration. 6 days before admission her symptoms did aggravate. On physical examination the patient showed abdominal distention. The liver was enlarged and its edge was palpable 11 cm under the costal margin in the right midclavicular line. Cardiopulmonary examinations was unremarkable. Her family and past histories were not contributory. Laboratory tests and tumour markers were within the normal limits.

38. The chest radiograph showed elevation of the right hemidiaphragm. Initial US scan showed liver enlargement and the right lobe was nearly completely filled with tumor mass. A CT scan revealed a a bulky mass 20x16x17 cm in the right lobe of the liver, inhomogeneously enhancing in the late phase. CT cannot rule out infiltrating the inferior vena cava from the diaphragm level till the renal arteries. The spleen was enlarged, but without any other changes. The right kidney was pushed down and enlarged with signs of urine retention. The left kidney was normal.