Clinical Characteristics Of Patients With Venous Thromboembolism: Comparison Between Cancer And Non-Cancer Patients

Background and purpose:Venous Thromboembolism(VTE),including Deep Venous Thrombosis(DVT) and Pulmonary Thromboembolism(PTE), is a life-threatening disease with a considerable morbidity and mortality[1].Many clinical studies have described the epidemic investigation of VTE[2], the annual incidence of VTE in the United States and Western Europe is 1.22/1000 [3] and 1.83/1000[4] , respectively. No precise date reported in China so far. The correlation between VTE and cancer has been revealed in domestic and abroad[5]. Malignancy which first associated with thrombotic tendency was back in 1865 [6], Trousseau A demonstrated that cancer was one of the most important factors in VTE. About 20% of patients with an idiopathic VTE will harbour an occult cancer[7]. Half of these can probably be detected after a focused history, examination, routine blood tests and a chest x ray. Recent studies confirmed that VTE increased the mortality of cancer patients[8,9]. Donati et al revealed that thrombosis was the second death causes in cancer patients,except cancer itself. VTE can develop in any stage of cancer,either in the occult cancer,or in the advanced cancer. VTE aggravates the mortality and morbidity of cancer patients. Therefore, it's meaningful to identify the clinical characteristics of cancer patients combined with VTE.Many clinical studies have described the epidemiologic, demographic andclinical characteristics of patients with VTE, including the impact and frequency of different risk factors. However, there is a large variability in the reported data, depending on location, study design, number of patients, etc. Moreover, only a few studies directly compared with cancer and non-cancer patients. Our sduty focused on the retrospective evaluation of clinical characteristics of patients with symptomatic venous thromboembolism: comparison between cancer and non-cancer patients,which helps early identify and treat the patients of cancer combined with VTE.Patients and Methods:1. PatientsBetween January 2002 and March 2007, all patients diagnosed at the Sir Run Run Sir Hospital affiliated to Medical College of Zhejiang University as suffering from a acute symptomatic venous thromboembolic event (deep vein thrombosis and/or pulmonary embolism), based on diagnostic findings on Doppler ultrasonography, diagnostic spiral computed tomography scan,high probability pulmonary scan for pulmonary embolism etc, were retrospectively enrolled and evaluated. Deep venous thrombosis and pulmonary thromboembolism were defined using previously validated ICD-9-CM codes: 451.1x;451.2;451.81;453.1;453.2;453.8; 453.9; 415.1x[10].The time of symptoms onset is less than 2 months.2. Diagnostic criteriaOn the reference of guidelines of diagnosis and treatment of Pulmonary Thromboembolism published by Chinese Medical Association respiratory branch, and standards of imaging tests of Pulmonary Thromboembolism-Deep Venous Thrombosis published by National Collaboraion of prophylaxis and treatment on Pulmonary Embolism-Deep Venous Thrombosis,we defined the criteria of DVT ,PTE and PTE clinical types. Cancers were diagnosed on the basis of pathology.3. Data collectionObtained demography of acute symptomatic VTE patients, including sex,age,height, weight etc. Risk factors,including ashma,chronic obstructive lung disease, coronary heart disease,heart failure,recent immorbility or operation,smoke,past VTE. VTEfamily history,hormone use and central venous inserted catheter etc. Laborotarytest,inciuding coagulative function,D-dimer, complete blood count, chemicals, rightventricular systolic pressure (RVSP) in echo, ventilation/perfusion scan (V/Q scan)and computed tomographic pulmonary angiography (CTPA) etc.4. Statistical analysis:Apply SPSS15.0 for Windows software for statistical analysis. Continuous variableswere compared by means of the Independent-Samples t Test,by means of x±s,nonnormal distribution variables were compared by means of the Mann-Whitney U test. Categorical variables were compared by means of the chi-square test. Statistical signiicance was determined if P was < 0.05.Result:Altogether,227 patients(male 106pts vs. female 121 pts) were identified and 264 VTE events diagnosed. The average onset age of cancer (30pts, 13%) and non-cancer group was 62.8±10.9 and 54.8±15.5 yo,respectively(P=0.008). Most of the cancer patients(18pts,58%) had advanced disease(stage III or IV),14pts(45%) of which received chemotherapy. There was no significant difference between cancer and non-cancer patients on VTE type (P=0.509).The most common cancer types were lung(8pts), breast(5pts),colon(4pts) and lymphoma((4pts)(26%, 16%, 13% and 13%,respectively). Other than cancer and chemotherapy,the most common risk factors for VTE were smoke(40pts,15%),past VTE(39pts, 15%), recent immorbility (36pts,14%) and operation(36pts,14%).Among cancer and non-cancer patients, past VTE(3% vs. 17%,repectively), recent immorbility(28% vs. 11%, repectively),recent operation(33% vs. 11%, repectively),hormone use(17% vs. 1%, repectively) and central venous inserted catheter(14% vs. 4%,repectively) had significant difference(P<0.05),there was no difference in any other risk factors. The average value of hemoglobin was 10.7±2.7 and 12.3±2.3g/dl,which had significant difference (p=0.001).Oher laboratory tests including serum triglyceride,cholesterol,oxygenation index,coagulative function,white cell count and platelet count had no significantdifference. The number of PTE patients whose RVSP more than 30mmHg were 67 (64%).RVSP had no significant difference between cancer and non-cancer patients(P=0.696).Among PTE patients,the number of cancer and non-cancer patients were 19(20%) and 76,respectively.Most patients were non-massive PTE patients. There was no significant difference between cancer and non-cancer patients on PTE type (P=0.876).Conclusion:1. Among acute symptomatic VTE, the rate of cancer patients was much lower than most of the foreign studies,but similar to some domestic studies.2. The average age of cancer patients was older than non-cancer patients. Amony cancer patients,the rate of risk factors including recent immorbility,recent operation,hormone use and central venous inserted catheter were higher than non-cancer patients,whereas past VTE rate was lower than non-cancer patients. Therefore, when suffering from immorbility,operation,hormone use and central venous inserted catheter,older cancer patients were prone to develop VTE. Reinforced prophylactic measures should be managed.3. Among laboratory test, hemoglobin value was lower than non-cancer patients,other tests including serum cholesterol, D-dimer had no significant difference.4. There were no significant difference between cancer and non-cancer patients on RVSP and PTE type.