Endometriosis is a condition where endometrial stroma and glands occur outside of the uterus frequently localizing over the peritoneal surface and ovaries.1 There are unusual descriptions of this disease outside of the pelvic cavity such as pulmonary, pleural, cardiac, vesicular, gastrointestinal, renal, umbilical, abdominal and hepatic wall.2 In an extensive review of the literature less than 20 cases of hepatic endometriosis have been reported worldwide.2,3 The most common presentation of hepatic endometriosis is a cystic mass called “endometrioma”. Here, we present a case of an incidental intraparenchymal hepatic endometriosis in a young woman who presented with only right upper quadrant pain.
A 25-year-old nulliparous woman was referred to our unit due to an 8-month history of relapsing and remitting right upper quadrant pain. In the last month, these episodes occurred more often and were related to the ingestion of fatty foods. There were no other symptoms. Her past gynecological history included menses onset at 13 years of age, with regular menstrauation accompanied occasionally with mild abdominal cramps. Examination revealed slight right upper quadrant tenderness. Except for hemoglobin level of 10.9 g/dL (13.0-16.5 g/dL), the routine laboratory tests were normal including enzymes. An abdominal ultrasound showed multiple small size gallstones. Because of suspecting symptomatic cholelithiasis, a laparoscopic cholecystecomy was performed. During the procedure, incidentally on the surface of the right liver lobe a 6 x 5 cm irregular rounded hemorrhagic area was found (Figure 1A). Also, in the right upper parietal peritoneum small patches of hemorrhagic areas were noted (Figure 1B). Multiple biopsies were taken from the liver capsule and the parietal peritoneum. Histological analysis showed the presence of endometrial glands surrounded by a mantle of densely packed small fusiform cells with scanty cytoplasm and bland cytology, typical of non-neoplastic endometrial stromal cells (Figure 2A). This was confirmed by positive immunostaining for progesterone receptors (Figure 2B) in both the glandular and stromal components. Biopsies from parietal peritoneum also showed foci of endometriosis. The patient made an uneventful recovery and was discharged home 2 days later. At follow up she is was started on danazol and remains asymptomatic since.
Photomicrography of liver biopsy showing typical endometrial tissue with both glandular and stromal components surrounded by fibrous tissue. Endometrial stromal cells are rounded with large and eosinophilic cytoplasm (haematoxylin and eosin stain) (A). Positive nuclear immunostaining with progesterone receptor specific antibody in nuclei of endometrial stromal cells (B).