Treatment outcome of patients with persistent gestational trophoblastic disease attended at Muhimbili National Hospital and Ocean Road Cancer Institute

Abstract

Background:Gestational trophoblastic disease (GTD) is a group of tumors that arise from abnormal proliferation of trophoblast of the placenta. The disease is divided into benign and malignant forms. The malignant forms of the disease which is the focus of this study are collectively known as Gestational trophoblastic Neoplasia (GTN). A true GTN include Choriocarcinoma, Placental Site Trophoblastic Tumor (PSTT) and Epithelioid Trophoblastic Tumor (ETT). In case of missing tissue for definitive histological diagnosis, the malignant disease is diagnosed clinically on the basis of a rising serum β-hCG after molar pregnancy evacuation, and referred to as Persistent GTD. Objectives: To evaluate treatment outcome and survival of patients with persistent Gestational Trophoblastic Disease (GTD) attended at Muhimbili National Hospital (MNH) and Ocean Road Cancer Institute (ORCI) for a period of five years. Methodology: This retrospective cohort study was carried out on patients with persistent GTD, treated at MNH and ORCI between Jan, 2011 and Dec, 2015. Analysis was done by using Statistical Package for Social Science (SPSS v.20). Kaplan-Meier curves were used to establish 3years overall survival rate and log rank test was done to compare different survival curves. Results: 58 women were enrolled aged between 19 years and 51 years with a mean age of 33 years. In most cases diagnosis of the disease was made clinically based on serum β-hCG levels post molar pregnancy evacuation. Methotrexate was the most common (87.5%) single agent chemotherapy used in low risk disease while MAC (33.3%) and EMA/CO) werecommonly used in high risk disease Among patients with low risk disease 19 patients (61.3%) had complete response, 6 patients (19.4%) had persistent disease and only one patient (3.2%) had a recurrent disease. About 22.6% of patients with low risk disease had to be switched to second line chemotherapy. Among patients with high risk disease, the complete response rate was 42.9% (n=3) for MAC regimen and 75 % (n=9) for EMA/CO regimen. The 3-years overall survival according to Kaplan Meir analysis was 71%. Patients with early stage disease (FIGO stage I & II) and those with WHO prognostic score of 0-6 had bettersurvival rate.

Conclusion: The three years survival rate of patients with persistent gestational trophoblastic disease (GTD) attended at Muhimbili National Hospital (MNH) and Ocean Road Cancer Institute (ORCI) was 71%. Methotrexate was the commonest chemotherapy used for low risk disease and EMA/CO was the commonest chemotherapy regimen used for high risk disease.