Upper New York State Society of Cytology,Inc.

Interesting Case 2

Submitted by: Lonnie DeCavallas, CT(ASCP) and Meg Jones, CT(ASCP)

Department of Pathology- St. Peter's Hospital - Albany, NY

History:

A 46 year-old male presented with lower flank discomfort. He had a history of loose stools in the morning for the past 4 months.

Physical exam revealed a left inguinal hernia. The hernia repair revealed thick pools of mucin, however, the source of mucin was unclear.

CT revealed abdominal ascites with a possible pancreatic cystic lesion. The patient was referred for an Endoscopic Ultrasound Guided(EUS) FNA. The liver(hilar area) was sampled.

Cellular Findings:

Flat sheets of reactive mesothelial and benign-appearing glandular epithelial cells are present in a background of thick mucoid material. No significant cytologic atypia was observed. However, exploratory surgery of the abdomen revealed a tumor extending into the bowel wall.

Diagnosis/Discussion:

Specimen interpretation: Inconclusive(see comment).

The constellation of clinical and cytologic findings are suggestive of disseminated peritoneal adenomucinosis(DPAM). Recent studies have shown that pseudomyxoma peritonei/gelatinous ascites can be divided cytologically into cases with DPAM, peritoneal mucinous carcinomatosis, and cases with both components(1). In this case, the benign cytologic appearance suggests DPAM; however, it is unclear whether the glandular epithelial component is responsible for the extracellular mucin or represents native gastrointestinal epithelium removed during the procedure. In addition, cases of pseudomyxoma peritonei are usually associated with a primary mucinous neoplasm, often appendiceal. Therefore, the final determination of the benign or malignant nature of this process should incorporate data regarding a potential primary source of gelatinous ascites.

The patient received chemotherapy and subsequent debulking surgery after the bowel perforation had healed.

References:

1. Jackson S, Fleming R, et al. Gelatinous ascites: a cytohistologic study of PMP in 67 patients. Mod Path, 2001.14(7): p. 664-671.