Incidence and Clinical Characteristic of Venous Thromboembolism in Gynecologic Oncology Patients attending King Chulalongkorn Memorial Hospital over a 10 Year Period

Background: Venous thromboembolisms (VTEs) constitute a group of diseases including deep vein thrombosis (DVT) and pulmonary embolism (PE). They regarded as the second leading cause of death in cancer patients and several studies have confirmed that VTEs have a negative impact on survival and recurrent rate in both ovarian and endometrial cancer cases. The incidence of VTEs differs worldwide and depends on several risk factors including race, underlying disease, lifestyle, body weight, BMI and genetic risk factors. There is heterogeneity of DVT rates between Asian and Western countries. This study was conducted in order to evaluate the character and incidence of VTEs in gynecologic oncology patients in King Chulalongkorn Memorial Hospital over a 10 year period. Materials and Methods: A retrospective chart review was performed with VTEs defined as objective diagnosis of acute DVT or PE with typical symptoms and signs. Diagnoses were approved byan internist and/or confirmed with imaging studies. Data from both outpatient and inpatient sessions of the affected cases from January 2004 to December 2013 were extracted. General characteristics of the patients were collected with details of the diseases, types of cancer, stage, date of diagnosis of cancer, operative data, treatment outcome, progression free survival and overall survival. Results: Thirty cases of VTEs were identified in a total 2,316 gynecologic oncology cases. The incidence of symptomatic VTEs in total gynecologic oncology patients in our institution is 1.295%. The incidence of VTEs in ovarian cancer patients in our institution was 5.9%. Duration for VTE detection ranged from 13 months before diagnosis of cancer to 33 months after diagnosis of cancer. Most of the VTE cases were detected in ovarian cancer patients (60%). The most common cell type was adenocarcinoma (moderately to poorly differentiated) which accounted for 26.7% of the cases. The second most common cell type was clear cell carcinoma with 23.3% of the cases. Thirty percent of VTE cases developed before cancer was diagnosed, 20% were diagnosed at the same time as cancer detection and fifty percent developed after cancer was diagnosed. Median disease free survival of the gynecologic oncology patients with VTE was 7.5 months. Median overall survival (OS) was 12 months. Median progession free survivals of DVT and PE groups were 11.5 and 5.5 months, respectively. OS of DVT and PE was 12.0 and 11.5 months respectively. Conclusions: The incidence of VTE in Asian countries is believed to be lower than in European or Western countries. From our retrospective review, the incidence of VTEs in all types of gynecologic oncology was 1.295%, much lower than reported in the West. The reason for the lower incidence may genetic differences. Another factor is that VTE in this review was symptomatic, which is less than asymptomatic VTE. More than half of VTEs in this study developed in ovarian cancer patients. The results are compatible with earlier reports that among gynecologic malignancies, the incidence of VTE is highest in ovarian cancer.