Placental site trophoblastic tumor

Human placental lactogen (HPL) is a 22-kD protein with partial homology to growth hormone. HPL is secreted by syncytiotrophoblastic cells in choriocarcinoma and intermediate trophoblasts in a testicular trophoblastic tumor that is a counterpart to a uterine placental site trophoblastic tumor. 

Ulbright TM, Young RH, Scully RE. Trophoblastic tumors of the testis other than classic choriocarcinoma monophasic choriocarcinoma and placental site trophoblastic tumor a report of two cases. Am J Surg Pathol. 1997 21 282. 

This tumor is composed of neoplastic implantation site intermediate trophoblasts that inhltrate myometrium. hPL and HLA-G are typically expressed. Placental site trophoblastic tumors have an index of 14% (+/- 7%) PSTTs can also contain scattered hCG-expressing syn-cytiotrophoblasts, but they are rare and haphazardly situated, not intimately admixed with mononuclear trophoblasts as is typical of choriocarcinoma. Biopsy or curettage material may suggest the presence of PSTT or placental site nodule. Both the immunophenotype and proliferative index of these lesions differ, with preferential expression of hPL and HLA-G in PSTT, as opposed to FLAP and p63 in placental site nodule. 749... 

Shih IM, Kurman RJ. Ki-67 labeling index in the diffetential diagnosis of exaggerated placental site, placental site trophoblastic tumor, and choriocarcinoma A double immunohistochemi-cal staining technique using Ki-67 and Mel-CAM antibodies. Hum Pathol. 1998 29 27-33. 

Follicular lymphoma, B-cell lymphoma, plasma cell neoplasia, hepatocellular carcinoma, placental site trophoblastic tumor, rhabdomyosarcoma, Ewing s sarcoma... 

Human placental lactogen Placental site trophoblastic tumor Trophoblasts... 

Shih IM, Kurman RJ. p63 Expression is useful in the distinction of epithelioid trophoblastic and placental site ttophoblastic tumors by profiling trophoblastic subpopulations. Am J Surg Pathol. 2004 28 1177-1183. 

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