Ectopic mesothelial cell proliferation in cervical lymph nodes after severe ovarian hyperstimulation syndrome.

Objective: To report a case of ectopic mesothelial proliferation in cervical lymph nodes after severe ovarian hyperstimulation syndrome.

Design: Case report.

Setting: University-affiliated teaching hospital.

Patient(s): A 42-year-old woman underwent a successful IVF attempt and developed severe ovarian hyperstimulation syndrome and pathologically enlarged cervical lymph nodes.

Intervention(s): Paracentesis, cervical lymph node biopsy followed by cytology, histology, and immunohistochemistry.

Main Outcome Measure(s): Resolution of symptoms, pregnancy outcome, correct pathological diagnosis.

Result(s): Paracentesis resulted in resolution of symptoms of ovarian hyperstimulation. The diagnosis of ectopic mesothelial proliferation in cervical lymph nodes was made after immunohistochemical examination of cervical lymph nodes. The pregnancy progressed normally, and at 40 weeks the patient spontaneously delivered a healthy son weighing 3,060 g.

Conclusion(s): This case describes ectopic mesothelial cell proliferation localized in and around cervical lymph nodes occurring at 9 weeks' gestation in a patient who earlier developed severe ovarian hyperstimulation syndrome 10 days after ET. Ectopic mesothelial cell proliferation in lymph nodes is an extremely rare event, and this is the first case described after ovarian hyperstimulation. Familiarity with this event is important for the clinician as well as for the pathologist in preventing the misdiagnosis of malignancy.