Serous surface papillary cystadenoma of fallopian tube clinically presenting with ectopic pregnancy

Herein reported is the rare case of serous surface papillary cystadenoma (SSPC) of fallopian tube who presented with signs and symptoms of ectopic pregnancy. A 31-year-old woman presented with abdominal pain and elevation of serum human chorionic gonadotropin (hCG) (2,530 IU/L). Pelvic ultrasound examination suggested a rupture of right tubal pregnancy. Emergency laparotomy was performed, and right fallopian tube was resected. Pathologically, the fallopian tube was totally replaced by SSPC, but no evidence for pregnancy (chorionic villi, fetus, decidua, amnion, and cord) was seen. The SSPC was unilocular, and was surrounded by multiple papillary proliferations of serous cells with fibro-vascular cores, which were recognized both in the surface areas and in the intracystic inner aspects. The tumor cells of the SSPC were negative for hCG. After operation hCG returned to the normal range, and the patient was recovered with no complications. A rare case of SSPC of fallopian tube with pseudo-manifestations of ectopic pregnancy is reported. The raised serum hCG and its return to the normal ranges after the tube resection are completely unclear and enigma.