Mesothelial pelvic lymph node inclusion in a patient with ovarian microinvasive borderline mucinous tumor: case report with review of the literature.

The presence of mesothelial cell inclusions in lymph nodes is rare. Localization of these inclusions in abdominal and pelvic lymph nodes is an exceedingly rare event, with only eight cases reported. We report here a case of mesothelial cell inclusions in pelvic lymph node of a patient with ovarian microinvasive borderline mucinous tumor. This case differs from the previously reported cases for the following reasons. First, there was no evidence of serosal effusion. Second, it is the first reported case of nodal mesothelial inclusions in a patient with ovarian microinvasive mucinous borderline tumor. Last, histologically, mesothelial cell inclusions were accompanied by psammoma bodies. The potential problem of misdiagnosis as a metastatic tumor can be avoided by an awareness of these inclusions, supported by immunohistochemical results.