Image of the Month—Diagnosis

Frozen section analysis of biopsy material could not clearly distinguish between lymphangioma, lymphangiosarcoma, teratoma, or the possibility of an inflammatory pseudotumor; a small blue-cell tumor, however, was excluded. Contents of the cysts appeared chylous. The final pathology analysis was consistent with a benign giant multicystic lymphangioma (or cystic hygroma). Mucin stains were negative; trichrome staining confirmed the presence of smooth muscle strands within the cyst walls.

Giant multicystic lymphangiomas are rare congenital malformations of the lymphatic system. These lesions result from a proliferation of dilated lymphatic spaces lined by thin endothelial layers.¹ They are thought to develop when primary lymphatic sacs fail to join the lymphatic system during embryologic development.^2,3 Lymphangiomas rarely present as intra-abdominal tumors; the majority of those that do are found in younger children. Lymphangiomas most commonly occur within the soft tissues of the head and neck, and they are also called cystic hygromas.⁴ Within the abdomen, the most common site is the small-bowel mesentery, followed by omentum, mesocolon, and retroperitoneum.⁵ Spontaneous regression of lymphangiomas appears to be rare, and the usual course is continued expansion. Rapid enlargement might also occur in association with infection, trauma, or erosion into a vessel and hemorrhage.² Complete resection with negative microscopic margins might be impossible and might account for the overall 10% postoperative recurrence rate.⁶

Intestinal duplications are uncommon congenital abnormalities. Usually observed early in life, a small number of cases might remain undiagnosed until adulthood. Intestinal duplications share a common wall and blood supply with native bowel; some cysts carry ectopic gastric or pancreatic epithelium. The clinical presentation can vary depending on the location; possible complications include bleeding, abdominal pain, intussusception, or malignant degeneration. Computed tomography is useful in delineating surrounding structures. After the diagnosis is established, surgical correction is the treatment of choice, preferably with complete removal.^7,8 A giant chylous duplication cyst has been described as well.⁹

Desmoplastic small round cell tumors are rare, highly aggressive malignant tumors found in adolescent males. The histologic appearance is that of a small blue-cell tumor; the cells carry a characteristic translocation, t(11;22)(p13;q12), resulting in a fusion between the Ewing sarcoma gene and the Wilms tumor gene. Most patients present with large masses in the abdomen or pelvis, which can be partly cystic. The overall survival rate is low, even after extensive resections; patients treated with aggressive chemotherapy followed by operative cytoreduction tend to have better outcomes.¹⁰ For this reason, the presence of a small blue-cell tumor should be excluded prior to committing to a resection of a large abdominal tumor in an adolescent.

Cysticercosis results from the larval infection with the pork tapeworm, Taenia solium. It is a potentially dangerous infection that usually manifests itself within the central nervous system or eye, but involvement of muscle or soft tissue, including extrahepatic intra-abdominal sites, have been reported.^11,12 The multiloculated cysts might be calcified. Treatment with albendazole or praziquantel is preferred; operative therapy might be necessary to control specific, localized complications.

Correspondence: Roderich E. Schwarz, MD, PhD, Cancer Institute of New Jersey, Department of Surgery, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, 195 Little Albany St, New Brunswick, NJ 08903-2681 (r.schwarz@umdnj.edu).

Accepted for Publication: June 15, 2003.