Placental site trophoblastic tumor - a challenging rare entity

Placental site trophoblastic tumor (PSTT) is a challenging rare variant of gestational trophoblastic disease (GTD) with variable characteristics. Historically, it was first described in 1895 and was considered a benign lesion until Scully and Young recognized its malignant potential in 1981. Current knowledge related to PSTT is largely based on the experience of handling this disease in established trophoblastic disease centers and on the experience of authors who reported small series or singular cases. In contrast to other forms of GTD, it arises from the implantation-site intermediate trophoblast, produces less beta-hCG and is less sensitive to chemotherapy. More than half of the patients present with disease confined to the uterus, whereas the remainder present with disease extension beyond the uterus. Because of the relative insensitivity to chemotherapy, simple hysterectomy is the mainstay of treatment. While the outcome of patients with disease confined to the uterus is usually excellent, most patients with disease extension beyond the uterus experience progression of disease and die despite surgery and aggressive chemotherapy. Other important adverse prognostic factors are interval from antecedent pregnancy > 2 years, age > 40 years and mitotic count > 5 mf/10 HPF Although the ideal chemotherapy regimen for PSTT has yet not been established, it seems that the EP/EMA regimen is the most effective first-line chemotherapy available to date for metastatic and relapsing PSTT. Although PSTT produces less hCG than choriocarcinoma, beta-hCG is still the best available serum marker to follow the disease and treatment course of PSTT.

Intermediate trophoblast; Implantation site; Gestational trophoblastic disease; Hysterectomy; Chemotherapy

[1] Feltmate C.M., Genest D.R., Wise L, Bernstein M.R., Goldstein D.P., Berkovitz R.S.: "Placental site trophoblastic tumor: a 17-year expenence at the New England Trophoblastic Disease Center”. Gynecol. Oneal., 2001, 82, 415.

[2] Papadopoulos A.J., Foskett M., Seek! M.J., McNeish I., Paradinas F.J., Rees H., Newlands E.S.:'Twenty-five years'clinical experience with placental site trophoblastic tumors“ J. Reprod. Med., 2002, 47, 460.

[3] Hassadia A., Gillespie A., Tidy J., Everard J., Wells M., Coleman R., Hancock B.: "Placental site trophoblastic tumour: Clinical features and management". Gynecol. Oneal., 2005, 99, 603.

[4] Baergen R.N., Rutgers J.L., Young R.H., Osann K., Scully R.E.: "Placental site trophoblastic tumor: A study of 55 cases and review of the literature emphasizing factors of prognostic significance". Gynecol. Oncol., 2006, 100, 511.

[5] Shih I-M., Mazur M.T., Kurman R.J.: "Gestationanl trophoblastic disease and related lesions". In: Kurman R.J. (ed.). "Blaustein's Pathology of the Female Genital Tract", 5th edition, New York, Berlin, Heidelberg, Springer-Verlag, 2002, 1193.

[6] Kurman R.J., Scully R.E., Norris H.J.: "Trophoblastic pseudotumor of the uterus. An exaggerated form of "synctial endometritis" simulating a malignant tumor". Cancer, 1976, 38, 1214.

[7] Twiggs L.B., Okagaki T., Phillips G.L., Stroemer J.R., Adcock L.L.: "Trophoblastic pseudotumor - evidence of malignant disease potential". Gynecol. Oncol., 1981, 12, 238.

[8] Scully R.E., Young R.H.: "Trophoblastic pseudotumor: a reappraisal". Am. J. Surg. Pathol., 1981, 5, 75.

[9] Kim S.J.: "Placental site trophoblastic tumor". Best Pract. Res. Clin. Obstet. Gynecol., 2003, 17, 969.

[10] Shih I.M., Kurman R.J.: "Epithelioid trophoblastic tumor: a rare neoplasm distinct from choriocarcinoma and placental site trophoblastic tumor simulating carcinoma". Am. J. Surg. Pathol., 1998, 22, 1393.

[11] Shih I.M., Kurman R.J.:'The pathology of intermediate trophoblastic tumors and tumor-like lesions". Int. J. Gynecol. Pathol., 2001, 20, 31.

[12] Machtinger R., Gotlieb W., Korach J., Fridman E., Apter S., Goldenberg M., Ben-Baruch G.: "Placental site trophoblastic tumor: outcome of five cases including fertility preserving management". Gynecol. Oneal., 2005, 96, 56.

[13] Nigam S., Singhal N., Gupta S.K., Chhabra D., Manaktala U.: "Placental site trophoblastic tumor in a postmenopausal female -A case report". Gynecol. Oncol., 2004, 93, 550.

[14] Dainty L.A., Winter W.E., Maxwell G.L.: "The clinical behavior of placental site trophoblastic tumor and contemporary methods of management". Clin. Obstet. Gynecol., 2003, 46, 607.

[15] FIGO Oncology Committee. FIGO staging for gestational trophoblastic neoplasia. int. J. Obstet. Gynecol., 2002, 77, 285.

[16] Guvendagguven E.S., Guven S., Esinler I., Ayhan A., Kucukali T., Usubutun A.: "Placental site trophoblastic tumor in a patient with brain and lung metastases". Int. J. Gynecol. Cancer, 2004, 14, 558.

[17] Palmieri C., Fisher R.A., Sebire N., Lindsay I., Smith J.R., McG!uggage W.G. et al.: "Placental site trophoblastic tumor arising from a partial hydatidifrom mole". Lancet, 2005, 355, 688.

[18] Moore-Maxwell C.A., Robboy S.J.: "Placental site trophoblastic tumor arising from antecedent molar pregnancy". Gynecol. Oneal., 2004, 92, 708.

[19] McLellan R., Buscema J., Currie J.L., Woodruff J.D.: "Placental site trophoblastic tumor in a postmenopausal woman". Am. J. Clin. Pathol., 1991, 95, 670.

[20] Metindir J., Pak I., Ozdilekcan C., Eren E.: "Chemoresistant placental site trophoblastic tumor with hilar lymph node metastasis: an unusual site of involvement". Gyncol. Oncol., 2005, 96, 552.

[21] Sakhel K., Khalil A., Kaspar H., Azar G., Mansour A., Nassar A.: "Placental site trophoblastic tumor in a patient with secondary infertility and radiological findings consistent with a leiomyoma: a case report". Int. J. Gynecol. Cancer, 2004, 14, 694.

[22] Tsuji Y., Tsubamoto H., Hori M., Ogasawara T., Koyama K.: "Case of PSTT treated with chemotherapy followed by open uterine tumor resection to preserve fertility". Gynecol. Oncol., 2002, 87, 303.

[23] Ajithkumar T.V., Abraham E.K., Rejnishkumar R., Minimole A.L.: "Placental site trophoblastic tumor". Obstet. Gynecol. Surv., 2003, 5 8, 484.