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 andseveral studies have confirmed that VTEs have a negative impact on survival and recurrent rate in both ovarianand endometrial cancer cases. The incidence of VTEs differs worldwide and depends on several risk factorsincluding race, underlying disease, lifestyle, body weight, BMI and genetic risk factors. There is heterogeneityof DVT rates between Asian and Western countries. This study was conducted in order to evaluate the characterand incidence of VTEs in gynecologic oncology patients in King Chulalongkorn Memorial Hospital over a 10year period. Materials and
Methods: A retrospective chart review was performed with VTEs defined as objectivediagnosis 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 fromJanuary 2004 to December 2013 were extracted. General characteristics of the patients were collected with detailsof the diseases, types of cancer, stage, date of diagnosis of cancer, operative data, treatment outcome, progressionfree survival and overall survival.
Results: Thirty cases of VTEs were identified in a total 2,316 gynecologiconcology cases. The incidence of symptomatic VTEs in total gynecologic oncology patients in our institutionis 1.295%. The incidence of VTEs in ovarian cancer patients in our institution was 5.9%. Duration for VTEdetection ranged from 13 months before diagnosis of cancer to 33 months after diagnosis of cancer. Most of theVTE 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 celltype was clear cell carcinoma with 23.3% of the cases. Thirty percent of VTE cases developed before cancer wasdiagnosed, 20% were diagnosed at the same time as cancer detection and fifty percent developed after cancerwas 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 were11.5 and 5.5 months, respectively. OS of DVT and PE was 12.0 and 11.5 months respectively.
Conclusions: Theincidence of VTE in Asian countries is believed to be lower than in European or Western countries. From ourretrospective review, the incidence of VTEs in all types of gynecologic oncology was 1.295%, much lower thanreported in the West. The reason for the lower incidence may genetic differences. Another factor is that VTEin this review was symptomatic, which is less than asymptomatic VTE. More than half of VTEs in this studydeveloped in ovarian cancer patients. The results are compatible with earlier reports that among gynecologicmalignancies, the incidence of VTE is highest in ovarian cancer.