EXTRAUTERINE (TUBAL) PLACENTAL SITE NODULE

Aims: The clinicopathological and immunohistochemical features of the second case of placental site nodule (PSN) of extrauterine, tubal loca tion are presented, Methods and results: The lesion was incidentally f ound in the right tube during a cesarean section and eventual tubal li gation in a 23-year-old women gesta 2 para 1, after an uneventful 39-w eek intrauterine pregnancy, Grossly, the right Fallopian tube had a 1 cm dilatation filled by necrotic material, Microscopically, the lumen of the Fallopian tube was effaced and replaced by a rim of pleomorphic intermediate trophoblastic (IT) cells with pseudoinvasive parietal fe atures which were positive for human placental lactogen, placental alk aline phosphatase, epithelial membrane antigen and CAM5,2. The Ki67 in dex was 3%, Conclusion: Due to its bizarre microscopic appearance, thi s lesion should be included in the differential diagnosis with maligna nt conditions, Both origins from a previous subclinical extrauterine t ubal pregnancy and a possible migration of IT from a uterine implantat ion are considered.