Hemostatic Derangements in Patients with Solid Malignant Tumors

Patients with solid malignant tumor show an increased susceptibility to thromboembolic events as compared to the general population. Although clinical symptoms occur less frequently, disorders of coagulation are very common in such patients [1]. Thromboembolism is one of the most common causes of death in cancer patients [1]. Ovarian, pancreatic, prostatic and lung cancer, and mucin-producing carcinomas of gastrointestinal tract are among the malignancies most frequently associated with thromboembolic episodes [1]. The overall incidence of clinical thromboembolic disease (TED) in patients with cancer has been reported to vary between 1% and 11% [2]. The incidence of TED in postmortem studies of cancer patients is considerably higher. In one prospective study, Ambrus and associates reported that thrombosis and/or bleeding were the second most common cause of death in hospitalized cancer patients [3]. An abnormal result on routine tests of blood coagulation in cancer patients has been reported to occur in as many as 92% of the patients [4, 5]. A wide range of coagulation disturbances can occur in patients with malignancies, which can predispose patients to hemorrhage or thrombosis [6]. In 1974, the concept of “intravascular coagulation and fibrinolysis syndrome (ICF)” was introduced by Owen and Bowie and the purpose was to examine the incidence and type of hemostatic derangement in patients with cancer [7]. Cooper and associates classified this syndrome into three groups; decompensated which is defined by depressed platelets or fibrinogen levels along with other hemostatic abnormalities, compensated in which platelets or fibrinogen values are normal but other hemostatic tests are abnormally prolonged, and overcompensated whereas the platelets or fibrinogen are increased together with other hemostatic abnormalities. This has also been correlated with the conventional terms; acute, sub-acute and chronic DIC with decompensated, overcompensated and compensated DIC respectively [7, 8]. The aims of the study were to determine the presence of hemostatic derangements in patients suffering from solid malignant tumors. A secondary aim was to elucidate the association of intravascular coagulation and fibrinolysis (ICF) with grade of tumor, histologic type of tumor and presence of metastasis.

This case-controlled study was conducted during a period of six months, from January to July 2004. A total of 40 patients with solid malignant tumors of various organs were included in this study; 13 of these patients were admitted to Al-Yermok Teaching Hospital in Baghdad and 27 patients were from the Hospital of Radiation and Nuclear Medicine in Baghdad. Fifteen age and sex matched healthy volunteers were included in this present study as control group, 9 males and 6 females, the age range was 40-70 years for males and 40-60 years for females. After taking consent, data was collected on a questionnaire including the complete history of the disease, clinical findings on physical examination, with special attention to any evidence of increased bleeding or clotting tendency at enrollment or in the past since the diagnosis of malignancy; details regarding the tumour including grade, histologic type and distant metastasis; and laboratory data. All laboratory tests were performed in Al-Yermok Teaching Hospital Laboratory. We excluded patients with co-morbid conditions that could affect coagulation profile, or patients using certain medication or those with history of coagulation disorders. The platelet count was conducted on blood whereas plasma was isolated for remaining laboratory tests including prothrombin time (PT), activated partial thromboplastin time (aPTT), thrombin time (TT), fibrinogen and D-dimer. Patients were considered to have evidence of intravascular coagulation and fibrinolysis (ICF) syndrome if their plasma D-dimer level was more than 0.5µg/ml. The concept of ICF of Owen and Bowie was adopted and their classification of overcompensated, compensated and decompensated ICF was tested [8, 9] and an attempt was made to identify those key tests that might enable us to discover patients with coagulation problems. The D-dimer and platelets were used as indicators and separated the patients into four groups.

1. Patients with no ICF (normal D-dimer).
2. Those with overcompensated ICF (elevated D-dimer and elevated platelets count).
3. Those with compensated ICF (elevated D-dimer but normal platelets count).
4. Those with decompensated ICF (elevated D-dimer and decreased platelets count).

A battery of hemostatic tests were applied among these four groups, and several tests appeared to be helpful in differentiating those with no ICF, compensated ICF, overcompensated ICF and decompensated ICF. These were PT, APTT, fibrinogen level and TT. In this study, the FDP test which was used by Owen and Bowie study [7] has been replaced by D-dimer test for the diagnosis of ICF syndrome because the D-dimer test is regarded now to be more specific for fibrin degradation products whereas the formation of fibrinolytic degradation products (FDP), X, Y, D and E fragments may be either fibrinogen or fibrin derived following the plasmin digestion [9, 23]. Moreover, the criteria of Owen and Bowie for the diagnosis of ICF was utilized, although in recent years many new criteria were added to diagnose ICF [11, 12, 13] but none of these were applicable in the present study because of the non-availability of some of relevant laboratory tests. Pooled plasma from at least 4 healthy individuals, were prepared and divided into aliquots each contains 1 ml, stored at – 20Cº to be used simultaneously with patients plasma for a period not exceeding 10 days. Positive and negative control plasma (for D-dimer test) was supplied with plasma D-dimer kit. The reference range of the hematological tests were platelet count 150000 – 400000, PT was 12 – 15 seconds, PTT was 32– 39 seconds, TT was 13 – 17 seconds, fibrinogen was 2.52-3.64 g/L, plasma D-dimer concentration < 0.5µg / ml.  Data were entered into a computerized database structure. Statistical analysis were done using SPSS version 10. The statistical significance of difference in rate of an outcome between 2 groups was assessed by Fisher´s exact significance test, while between more than 2 groups the likelihood test was used. The statistical significance of difference in mean of a continuous variable between 2 groups was assessed by t-test and between more than 2 groups by ANOVA test. The difference in median of an ordered variable (like D-dimer) between 2 groups was assessed by Mann-Whitney test and between more than 2 groups by Kruskal-Wallis test. Spearman´s rank was used to study the strength of association (linear correlation) between D-dimer as an ordered variable and other continuous variables. P value of less than 0.05 was considered statistically significant.

Forty patients were included in the malignancy group and 15 healthy controls were selected.

Thirteen of these patients were admitted to Al- Yermok Teaching Hospital in Baghdad, and the other 27 were recruited from the Hospital of Radiation and Nuclear Medicine in Baghdad. 26 were males (65%) in the malignancy group. The frequency distribution of age and sex in healthy controls and malignant cases are shown in Table 3. There were 26 males (65%) and 14 females (35%), their age ranged from 36 to 73 years for males and from 38 to 70 years for females. The primary sites of malignant disease and their frequency distribution are shown in Figure 1. The most frequent histologic types were adenocarcinoma, 29 patients (72.5%), transitional cell carcinoma, 4 patients (10.0 %), undifferentiated small cell carcinoma, 2 patients (5.0%), non–Hodgkins lymphoma, 2 patients (5.0%) and large cell carcinoma, 1 patient (2.5%). Among the forty cases, 6 (15%) had grade I, 17 (42.5%) had grade II, 12 (30%) had grade III, and 5 (12.5 %) had grade IV tumors, as determined by histology. In about half of the patients (55%, n=22), distant metastasis was present. Thirty-five percent (n=14) patients had slight concurrent bleeding; in 10 of them the bleeding was related to their malignant disease. These were gastrointestinal bleeding from carcinoma of the stomach and colon (n=2), hematuria from carcinoma of the prostate and urinary bladder (n=6) and hemoptysis from the carcinoma of the lung (n=2). While in the other 4 cases, the bleeding was not related to their malignant disease; these were epistaxis, bruising, ecchymosis and vaginal bleeding from the carcinoma of the breast, gall bladder and non – Hodgkin lymphoma. The evidence of thrombosis was encountered in one patient only. All patients were classified according to the results of D-dimer into 2 groups; those with negative D-dimer (considered having no evidence of ICF syndrome), this group consists of 22 patients (55% of cases) and those with positive D-dimer (considered having evidence of ICF syndrome), this group consists of 18 patients (45% of cases). As compared to the healthy controls, PT (p<0.001), aPTT (p<0.001) and TT (p=0.02) were significantly higher in patients with malignancy (Table 1). These variables were also higher in those with evidence of ICF as compared to those without ICF syndrome (Table 2).

Platelet count was significantly higher in patients with malignancy as compared to that in healthy controls (p=0.02) (Table 1). Although lower in ICF patients, the platelet count in patients without ICF was not significantly different from that in patients with ICF (p=0.24). Moreover, the platelet count tended to be lower when there was evidence of ICF of the decompensated type rather than compensated or overcompensated types as depicted in Table 2 (p<0.001). Fibrinogen level was lower in those with ICF (p <0.001) (Table 2). Although not statistically significant, fibrinogen level was slightly lower in decompensated state (2.3±0.3g/L) as compared to compensated (2.6±0.3g/L) and overcompensated ICF states (2.6±0.4g/L) (p=0.62) (Table 2). In this study, 10% (n=4) of cancer patients were diagnosed as decompensated ICF based on prolongation of PT, APTT, low platelet count and/or hyperfibrinogenemia and a positive D-dimer, but 5% (n=2) patients had normal fibrinogen level. Except for D-dimer concentration, the absence, presence of either high-grade tumor or distant metastasis or else the presence of both of these were not associated with a deranged coagulation profile (Table 3).