Placental site trophoblastic tumor in a patient with secondary infertility and radiological findings consistent with a leiomyoma: a case report

The Rare of the Rarest: Placental Site Trophoblastic Tumor, Epithelioid Trophoblastic Tumor, Atypical Placental Site Nodule

BACKGROUND

Epithelioid Trophoblastic Tumor (ETT) and Placental Site Trophoblastic Tumor (PSTT) are two of the rarest GTNs that share certain features at diagnosis and management. Atypical Placental Site Nodule (APSN) is a relatively new entity considered as a premalignant lesion.

OBJECTIVES AND METHODS

The aim of this review was to summarize the main characteristics of each of these entities, their diagnostic features, and their treatment's standard of care including fertility-sparing treatments.

OUTCOME

This study provides a thorough review of ETT, PSTT, and APSN.

CONCLUSIONS

The reader will gain an insight view of these rare tumors arising from the intermediate trophoblast.

Placental site trophoblastic tumor: a case report and review of the literature

We present a case of a gravida 1 para 1 woman, who presented with an 11-month history of amenorrhea after cesarean delivery. The patient was taking birth control pills at the time of presentation. She was observed with a slight elevation of serum β-hCG level, an enlarged heterogeneous uterus and hematometra. A biopsy was performed, and the patient was diagnosed with placental site trophoblastic tumor; the patient then underwent surgery. Placental site trophoblastic tumor is the rarest form of gestational trophoblastic disease, derived from intermediate trophoblast cells. It does not have a pathognomonic appearance; therefore, correlation with medical history, as well as results of laboratory tests and pathological analysis is mandatory. It is a relatively chemoresistant tumor, posing considerable therapeutic challenges; patients with localized disease are managed with surgery and those with metastatic disease require additional chemotherapy. Herein, we review the main features of this entity and top differential diagnosis, as the rarity of this tumor is associated with imaging and pathological pitfalls, reinforcing the need for further experience in this field.

Placental site trophoblastic tumor: report of four cases and review of literature

Placental site trophoblastic tumor (PSTT) is a rare variant of gestational trophoblastic disease that originates from the implantation site intermediate trophoblast. We report four patients with PSTT and review pertinent literature. Three patients presented with disease confined to the uterus and one patient with disease extension beyond the uterus. Antecedent pregnancy was full-term pregnancy in three patients and termination of a 21-week pregnancy in one patient. Interval from the antecedent pregnancy was <1 year in three patients and 13 years in one patient. Primary treatment was simple hysterectomy in three patients and radical hysterectomy in one patient. Overall, three patients received chemotherapy; one had EP/EMA as adjuvant chemotherapy, one had EMA/CO for rising levels of serum β-hCG and one had BEP then VIP for recurrent disease. The three patients with disease confined to the uterus have remained after treatment alive and with no evidence of disease, whereas the one patient with disease extension beyond the uterus died of disease despite surgery and aggressive chemotherapy. It is concluded that disease extension beyond the uterus is the most important adverse prognostic factor. Other adverse prognostic factors are interval from antecedent pregnancy >2 years, age >40 years, and mitotic count >5 mitotic figures/10 high-power fields. Because of the relative insensitivity to chemotherapy, hysterectomy is the mainstay of treatment. EP/EMA seems to be the most effective first-line chemotherapy available to date for metastatic and relapsing PSTT

Placental site trophoblastic tumor: A study of 55 cases and review of the literature emphasizing factors of prognostic significance

OBJECTIVE

The placental site trophoblastic tumor is a rare form of gestational trophoblastic disease. Fifteen percent of reported cases have been fatal, but predicting behavior in individual patients has been challenging.

METHODS

The clinical, gross and histopathological features of 55 cases and 180 cases in the literature were analyzed for their effect on survival and in relation to tumor stage.

RESULTS

The 55 patients in our series were 20 to 62 (average 32) years of age. The tumors occurred on an average of 34 months after the last known gestation. 84% were stage I, 2% stage II, 5% stage III, and 9% stage IV. Serum levels of human chorionic gonadotropin (hCG) were elevated (average 691 mIU/ml) in 77% of the cases. The tumors were on average 5 cm in greatest dimension and were composed microscopically of infiltrative sheets of intermediate (extravillous) trophoblastic cells. The mitotic rate ranged from 0 to 20 (average 5.0) per 10 high power fields. The follow-up interval averaged 4.6 years. Eight patients (15%) died from metastatic tumor, and nine additional patients had metastases or a recurrence but were alive at last contact. The most common metastatic sites were the lungs, liver, and vagina.

CONCLUSIONS

Significant factors associated with adverse survival in the present series were age over 35 years (P = 0.025), interval since the last pregnancy of over 2 years (P = 0.014), deep myometrial invasion (P = 0.006), stage III or IV (P < 0.0005), maximum hCG level > 1000 mIU/ml (P = 0.034), extensive coagulative necrosis (P = 0.024), high mitotic rate (P = 0.005), and the presence of cells with clear cytoplasm (P < 0.0005). Only stage and clear cytoplasm were independent predictors of overall survival, while stage and age were the only independent predictors of time to recurrence or disease-free survival. In the literature, factors associated with survival were stage (P < 0.005), interval from preceding pregnancy of over 2 years (P = 0.029), previous term pregnancy (P = 0.046), high mitotic rate (P < 0.0005), and high hCG level (P = 0.037).