Brett S. Carver, MD
BASICS
DESCRIPTION
• Chylous ascites is characterized by the accumulation of chyle in the peritoneal cavity.
• Results from the obstruction or injury of the thoracic duct or cisterna chyli of the lymphatic system.
• Lymphatic leakage from the lymph vessels draining the intestines.
• Characterized as a milky fluid due to the high triglyceride component.
• This section focuses primarily on chylous ascites associated with retroperitoneal lymph node dissection (RPLND) for testicular cancer
EPIDEMIOLOGY
Incidence
Chylous ascites is reported to occur in ∼1% of patients undergoing a primary RPLND for testicular cancer and 3% of postchemotherapy RPLNDs.
Prevalence
N/A
RISK FACTORS
• Predisposing factors for chylous ascites associated with RPLND:
– Surgical resection of the vena cava.
– Suprahilar dissection.
– Simultaneous hepatic resection.
– In addition, patients undergoing reoperative RPLND are at an increased risk.
Genetics
N/A
PATHOPHYSIOLOGY (1)
• Chylous ascites is caused by injury or obstruction of the thoracic duct or cisterna chyli.
• Surgical injury, ligation of the thoracic duct.
• Retroperitoneal tumor associated with obstruction of the thoracic duct.
• Leakage of fat containing lymphatic fluid into the peritoneum.
ASSOCIATED CONDITIONS
• Testicular cancer
• Peritonitis
• Ileus or small-bowel obstruction
• Failure to thrive
GENERAL PREVENTION
• Appropriate ligation of lymphatic vessels during surgery to minimize lymphatic leak.
• Preservation of the thoracic duct.
• Oral diet with low lipid, high medium-chain triglyceride content.
DIAGNOSIS
HISTORY
• Patients often present following RPLND with symptoms of abdominal distention and pain, decreased appetite, nausea, and vomiting.
• Shortness of breath may also be present associated with increased abdominal pressures.
• Secondary infection associated with peritonitis with symptoms of fever, chills, abdominal pain, and lethargy.
PHYSICAL EXAM
The most common finding on physical exam is distension of the abdomen with flank bulging. The abdomen is dull to percussion and may demonstrate a fluid wave upon palpation.
DIAGNOSTIC TESTS & INTERPRETATION
Lab
• Serum tumor markers (AFP, HCG, LDH) should be obtained to rule out recurrence.
• Aspiration of the abdominal fluid reveals a milky white fluid, which should be sent for triglyceride testing and culture to rule out a secondary infection.
– A fluid triglyceride level >110 mg/dL is diagnostic.
Imaging
• CT scan of the abdomen and pelvis is the imaging modality of choice to evaluate for the presence of ascites and rule out retroperitoneal recurrent disease.
• Abdominal ultrasonography may be used to document ascites and guide aspiration.
Diagnostic Procedures/Surgery
Abdominal paracentesis is performed to aspirate the ascites for diagnostic testing.
Pathologic Findings
Chylous ascites is grossly defined as a milky white fluid. Lab testing will reveal elevated triglyceride content.
DIFFERENTIAL DIAGNOSIS
• Chylous ascites can be caused by other conditions beyond RPLND for testicular cancer:
– Postoperative
Abdominal aneurysm repair
Peritoneal dialysis catheter placement
– Infectious/inflammatory
Pancreatitis
Retroperitoneal radiation
Pericarditis
Celiac disease
Retroperitoneal fibrosis
Sarcoid
TB
Filariasis
Mycobacterium avium-intracellulare (AIDS related)
– Neoplasm
Lymphoma
Kaposi sarcoma
Other solid tumors
– Other causes
Cirrhosis
Carcinoid
Nephrotic syndrome
Trauma
Right-sided heart failure
Dilated cardiomyopathy
Idiopathic
Congenital causes (defects of lacteal formation)
TREATMENT
GENERAL MEASURES
• All patients with abdominal distention following an RPLND should be evaluated for:
– Ascites (nonchylous)
– Ileus
– Small-bowel obstruction
– Recurrent disease in the abdomen or retroperitoneum.
• The majority of chylous effusions will heal spontaneously. Abdominal paracentesis is diagnostic and often therapeutic in relieving symptoms associated with increased abdominal pressures.
MEDICATION
First Line
• Low lipid, high medium chain triglyceride oral diet.
– MCT oil supplement
1 tablespoon (15 mL) 3–4 times/d
Mix with juices or otherwise incorporated into low-fat diet
Do not use in patients with advanced cirrhosis: Risk of narcosis and coma
• Somatostatin analogs have been demonstrated to be effective in reducing lymphorrhagia.
– Octreotide 100 mcg administered subcutaneously 3 times per day
Second Line
• Total parental nutrition is to be utilized in patients who fail oral diet modifications.
– Bowel rest may enhance recovery if conservative approaches are not successful
SURGERY/OTHER PROCEDURES
• Abdominal paracentesis, repeated as necessary.
– Primarily for pain control and dyspnea
• Surgical exploration with direct ligation of lymphatic vessels for persistent chylous ascites (2).
• Peritoneal venous shunts for refractory chylous ascites.
• Direct lymphatic vessel ligation or embolization of large leaking vessels using interventional radiologic techniques.
ADDITIONAL TREATMENT
Radiation Therapy
N/A
Additional Therapies
N/A
Complementary & Alternative Therapies
Orlistat (Xenical) has been used successfully in a nontesticular cancer case of chylous ascites (3)
ONGOING CARE
PROGNOSIS
The prognosis is excellent for the vast majority of cases as most will respond to conservative management.
COMPLICATIONS
• The complications of chylous ascites related to increased abdominal pressure:
– Renal failure
– Venous thrombosis
– Pulmonary embolism
– Atelectasis
– Pneumonia
• The gastrointestinal complications of chylous ascites include ileus and small-bowel obstruction.
– Malnourishment and failure to thrive may also occur due to protein-losing enteropathy with chronic diarrhea (steatorrhea), malabsorption, and malnutrition
FOLLOW-UP
Patient Monitoring
• Follow-up protocols should be followed according to guidelines established by the National Comprehensive Cancer Network for testicular cancer patients.
• After initial treatment of chylous ascites, patients should be seen in follow-up to monitor for recurrent ascites.
Patient Resources
N/A
REFERENCES
1. Carver BS, Sheinfeld J. Germ cell tumors of the testis. Ann Surg Oncol. 2005;12(11):871–880.
2. Castillo OA, Litvak JP, Kerkebe M, et al. Case report: laparoscopic management of massive chylous ascites after salvage laparoscopic retroperitoneal lymph-node dissection. J Endourol. 2006;20(6):394–396.
3. Chen J, Lin RK, Hassanein T. Use of orlistat (xenical) to treat chylous ascites. J Clin Gastroenterol. 2005;39(9):831–833.
ADDITIONAL READING
• Bosl GJ, Feldman DR, Bajorin DF, et al. Cancer of the testis. In: DeVita VT, Hellman S, Rosenberg SA, eds. Cancer: Principles and Practice of Oncology. 9th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2011:1280–1301.
• Evans JG, Spiess PE, Kamat AM, et al. Chylous ascites after post-chemotherapy retroperitoneal lymph node dissection: Review of the M. D. Anderson experience. J Urol. 2006;176(4 Pt 1):1463–1467.
• Link RE, Amin N, Kavoussi LR. Chylous ascites following retroperitoneal lymphadenectomy for testes cancer. Nat Clin Pract Urol. 2006;3(4):226–232.
See Also (Topic, Algorithm, Media)
• Chylous Ascites Image 
• Lymphatic Ascites
• Testis Cancer, Adult General Considerations
CODES
ICD9
• 125.9 Unspecified filariasis
• 457.8 Other noninfectious disorders of lymphatic channels
ICD10
• B74.9 Filariasis, unspecified
• I89.8 Oth noninfective disorders of lymphatic vessels and nodes
CLINICAL/SURGICAL PEARLS
• Chylous ascites occurs in ∼1–3% of patients undergoing a RPLND.
• Risk factors include vena cava resection, suprahilar dissections, and concomitant hepatic surgery.
• Initial management includes paracentesis for symptom of pain or pulmonary compromise and low lipid, high medium-chain triglyceride oral diet.