Cancer is the second leading cause of death globally, and is responsible for an estimated 9.6 million deaths in 2018. (The World Health Organization). Sickness rate of deep vein thromboses is approximately 100 per 100 000 population annually. However, having worked as a vascular surgeon for several years I was wondering, why I have never detected cancer? So I decided to analyze 100 cases of morbidity of deep vein thromboses. Thus for the period 2011-2018 there were identified 3 cases of cancer out of 100 cases of deep vein thromboses. Taking into account a rarity of cancer detection within the group of patients with deep thromboses, I decided to select a control group of 100 people with cancer who were hospitalized for the planned and urgent surgery to find out whether they had ever had deep vein thromboses, any deviations in their coagulograms or whether they had some current problems with the post-thrombotic complications.
The research objective:
- To determine whether peripheral vein thromboses are the complications of cancer
- To detect the significance of fibrinogen as a biochemical index of risks of thromboses in the selected groups of the patients.
- randomized prospective parallel controlled trial.
- randomized prospective controlled trial
In Russia there is a program according to which doctors should carry out the further survey of all the patients with deep vein thrombosis in order to identify cancer. Based on this program we conduct the following: X-ray examination of the chest cavity; ultrasound diagnostics of the abdominal cavity organs, retroperitoneal space and genitourinary system; fibrogastroduodenoscopy, fibrocolonoscopy, urologist/gynecologist examination; later, when the cancer is suspected – in-depth follow-up.
Moreover, all the patients should visit a vascular surgeon again in three months and later in 6 months to control the dynamics of vein recanalization and the relevance of the extension of anticoagulant therapy. Thus we can judge adequately about the presence or absence of suspicion of any tumor localization.
Additionally, 100 cases were analyzed (50 were diagnosed as cancer, 50 were diagnosed as deep vein thromboses) to detect the significance of fibrinogen as a laboratory index of risks of thromboses.
Assuming the equal probability of occurrence of both diseases – cancer and deep vein thromboses and experimental data, we can easily identify the following indicators which are commonly used in the evidence-based medical statistics.
In our case we suggest that we will not get even 50% cases of cancer from the group with deep vein thromboses and that we will not get even 50% cases of deep vein thromboses in the group with cancer.
Thus, the Beyes factor is 0.03.
Using Gaussian approximation P Value = 0.01 .
This result can be considered as the evidence of significant strength.
- Initially assuming that the positive reaction of the fibrinogen in cases of acute deep vein thromboses must be at least in 80% and 50% in cases of cancer (if cancer has factors which could be enough for the formations of clots and finally a disease-acute vein thrombosis).
The Beyes factor is 0.2 . Consequently, it excludes the correctness of the hypotheses.
We cannot argue that the key, trigger mechanism for starting such a disease as a deep vein thrombosis is cancer, and, so the deep vein thromboses cannot be considered as a complication of cancer.
Fibrinogen being not only a Factor I of the blood coagulation system but also a protein of the acute phase of inflammation completely loses its clinical prognostic value.