CYTODIAGNOSIS OF PLACENTAL SITE TROPHOBLASTIC TUMOR - A REPORT OF 2 CASES

BACKGROUND: Placental site trophoblastic tumor (PSTT) is a rare form o f trophoblastic neoplasm. Approximately 100 cases of PSTT have been re ported, but we found MO report on its cytodiagnosis. CASES: Case 1, a 39-year-old-female, came to the hospital because of abnormal genital b leeding. Case 2, a 36-year-old female, came because of amenorrhea for a year. In both cases, endometrial smear and intrauterine curettage su ggested trophoblastic disease, and hysterectomy was performed. Laborat ory data revealed a mild increase in human chorionic gonadotropin (hCG ) and beta-hCG but normal human placental lactogen (hPL). In the cytol ogic examination, the background contained some hemorrhagic and fibrin ous areas but no necrosis. Most tumor cells stained light green, were round or polygonal, and contained abundant cytoplasm. Some were palely stained and had vacuoles. Some cells showed hyperchromatism, an irreg ular nucleus, fine-to-coarse chromatin granules and markedly different sizes. Most gf the cells were hPL positive, and a few were hCG positi ve. CONCLUSION: Both cases were considered benign because of rare mito ses despite cellular pleomorphism. However, careful follow-up is requi red. The differential diagnosis of PSTT is difficult from cytologic an d biopsy specimens alone but may be achieved with additional magnetic resonance imaging findings and positive staining of hPL and hCG.