Zhang Y, et al. - Researchers assessed the clinical characteristics of intermediate trophoblastic tumor (ITT) by investigating 12 cases diagnosed at Qilu Hospital of Shandong University from January 2005 to December 2016 and analyzing 50 additional cases selected from MEDLINE and CBM databases between January 2010 and December 2016. Among these 62 cases, 42 cases had placental site trophoblastic tumor (PSTT), 19 cases had epithelioid trophoblastic tumor (ETT), and 1 case had mixed type (PSTT and ETT). Generally, PSTT and ETT displayed similar clinical characteristics. The progress of ITT could not be assessed with serum β-hCG. For ITT, age ≧ 40 years is established as the independent high-risk factor.