Chyloperitoneum in Advanced Ovarian Cancer

Clinical History

66-year-old female patient with advanced ovarian cancer and extensive lymphadenopathy in the thoracic, abdominal and pelvic region. Now incidental finding of loculated ascites with fat-fluid level on CT, eight months after hysterectomy, bilateral salpingoopherectomy, omentectomy, and right nephrectomy.

Imaging Findings

Unenhanced axial CT shows an encapsulated lesion in the mesentery of the duodeno-jejunal junction with an internal fat-fluid level. Abdominal adenopathy is seen. Subsequent contrast enhanced CT again showed ascitic collections with fat-fluid levels.

Discussion

Background:
Chyloperitoneum, a rare form of ascites, is associated with disruption of lymphatic drainage.

Clinical perspective:

Chyloperitoneum is usually asymptomatic, or can present with nonspecific symptoms like abdominal distension, nausea, weight loss, or fever. A rare presentation is chylous peritonitis, thought to be due to sudden accumulation of chyle in the right paracolic gutter causing right iliac fossa pain and thus can mimic acute appendicitis. [1]

Definitive diagnosis of chyloperitoneum is made with paracentesis; aspirated fluid has a characteristic milky, cloudy appearance. Biochemical confirmation of triglycerides can be performed.

Imaging perspective:

CT appearance of chyloperitoneum is nonspecific, with Hounsfield values indistinguishable from simple ascites. The rare finding of internal fat-fluid level is pathognomonic for chyloperitoneum, hypothesized to be due to (1) increased amount of lipid in the fluid collection and (2) if the level obstruction occurs at the level of the proximal jejunum, where most of the absorption of lipid occurs.

Outcome:

Management of patients with chyloperitoneum depends very much on the clinical presentation. Chyloperitoneum related to recent surgery (< 3 months) with lymphangiography findings of surgically correctable lymphatic leakage are thought to benefit from aggressive treatment, as they are hypothesized to have serious mechanical, nutritional and immunological consequences of the constant loss of protein and lymphocytes [2], in addition to the morbidity/mortality of recent surgery and underlying primary pathology.

In non-surgical cases, supportive treatment is implemented, which consists of (1) dietary treatment, such as a high protein, low fat diet with medium chain triglycerides and diuretics, or total parenteral nutrition, (2) paracentesis for symptomatic relief of large chyloperitoneum (e.g.: splinting of the diaphragm).

In patients with a large amount of ascites, paracentesis may be employed to give symptomatic relief; dyspnoea and discomfort can be easily released this way but the risk of infection and fat emboli should temper its use.

In this patient, in view of the advanced ovarian cancer, conservative management was decided between the patient and the attending physician. Thus, no paracentesis was performed, nor was there dietary restriction as the patient’s appetite was generally poor. She unfortunately expired two months after the first shown scan.

Teaching points:
1. Fat-fluid level in the peritoneal cavity is pathognomonic of chylous peritoneum.

2. In the appropriate clinical context, such as recent major retroperitoneal surgery, persistent ascites should raise the suspicion of chyloperitoneum. Management of chyloperitoneum with surgical repair, or conservative treatment improves prognosis in this group of patients.

Differential Diagnosis List

Final Diagnosis

Chyloperitoneum

URL:	https://www.eurorad.org/case/9279
DOI:	10.1594/EURORAD/CASE.9279
ISSN:	1563-4086