Retroperitoneal cystic abdominal lymphangiomatosis diagnosed by fine needle aspiration: a case report.

Background: Attributed to congenital malformation of lymphatic ducts, diffuse retroperitoneal cystic abdominal lymphangiomatosis has a distribution that often corresponds to the location of primitive fetal lymphatic sacs. Three recognized types are capillary, cavernous and cystic. Multisystem involvement may occur involving spleen, liver, bone, pancreas, soft tissue, limbs and brain.

Case: A 55-year-old, healthy male with multiple liver lesions and retroperitoneal lymphadenopathy presented for retroperitoneal fine needle aspiration, producing 20 mL of milky liquid. Immediate cytologic evaluation showed a heterologous population of mature lymphocytes with chylomicrons. Flow cytometry revealed a polyclonal population of mature lymphocytes. Chemical analysis demonstrated a normal serum cholesterol level and an elevated triglyceride level. Serum markers were noncontributory. We review the differential diagnostic considerations leading to obstruction or retention of lymphatic fluids (malignancy, surgical, infective and traumatic), with an emphasis on the importance of onsite cytologic evaluation, correlation with clinical history and review of the etiologic considerations.

Conclusion: The constellation of clinical, radiologic, cytologic and laboratory findings presented in this paper are diagnostic of diffuse retroperitoneal cystic abdominal lynmphangiomatosis. To our knowledge, this entity has not been reported before in the fine needle aspiration literature. To prevent further disruption of lymphatic drainage, no further surgical sampling is planned.