Background: Gestational trophoblastic neoplasia (GTN) is a spectrum of disease with abnormal trophoblastic proliferation. Treatment is based on FIGO stage and WHO risk factor scores. Patients whose score is 12 or more are considered as at extremely high risk with a high likelihood of resistance to first line treatment. Optimal therapy is therefore controversial. Objective: This study was conducted in order to summarize the regimen used for extremely high risk or resistant GTN patients in our institution the in past 10 years. Materials and Methods: All the charts of GTN patients classified as extremely high risk, recurrent or resistant during 1 January 2002 to 31 December 2011 were reviewed. Criteria for diagnosis of GTN were also assessed to confirm the diagnosis. FIGO stage and WHO risk prognostic score were also re-calculated to ensure the accuracy of the information. Patient characteristics were reviewed in the aspects of age, weight, height, BMI, presenting symptoms, metastatic area, lesions, FIGO stage, WHO risk factor score, serum hCG level, treatment regimen, adjuvant treatments, side effects and response to treatment, including disease free survival. Results: Eight patients meeting the criteria of extremely high risk or resistant GTN were included in this review. Mean age was 33.6 years (SD=13.5, range 17-53). Of the total, 3 were stage III (37.5%) and 5 were stage IV (62.5%). Mean duration from previous pregnancies to GTN was 17.6 months (SD 9.9). Mean serum hCG level was 864,589 mIU/ml (SD 98,151). Presenting symptoms of the patients were various such as hemoptysis, abdominal pain, headache, heavy vaginal bleeding and stroke. The most commonly used first line chemotherapeutic regimen in our institution was the VAC regimen which was given to 4 of 8 patients in this study. The most common second line chemotherapy was EMACO. Adjuvant radiation was given to most of the patients who had brain metastasis. Most of the patients have to delay chemotherapy for 1-2 weeks due to grade 2-3 leukopenia and require G-CSF to rescue from neutropenia. Five form 8 patients were still survived. Mean of disease free survival was 20.4 months. Two patients died of the disease, while another one patient died from sepsis of pressure sore wound. None of surviving patients developed recurrence of disease after complete treatment. Conclusions: In extremely high risk GTN patients, main treatment is multi-agent chemotherapy. In our institution, we usually use VAC as a first line treatment of high risk GTN, but since resistance is quite common, this may not suitable for extremely high risk GTN patients. The most commonly used second line multi-agent chemotherapy in our institution is EMA-CO. Adjuvant brain radiation was administered to most of the patients with brain metastasis in our institution. The survival rate is comparable to previous reviews. Our treatment demonstrated differences from other institutions but the survival is comparable. The limitation of this review is the number of cases is small due to rarity of the disease. Further trials or multicenter analyses may be considered.