Evaluation of Platelet Aggregability in Patients with Non-small Cell Lung Carcinomas

Cancer patients are at increased risk of thrombotic complications, especially venous thromboembolism (VTE). The oncology population is seven times more likely to develop thrombosis when compared to the general population, with an incidence of up to 20% of patients during follow-up. It is suggested that the reasons for this greater thrombotic risk are immobility, invasive procedures and changes in coagulation, in addition to possible disorders of platelet aggregation and endothelial function.

The literature suggests that the basic thromboembolic mechanism would be related to the production, by tumor cells, of pro-coagulant factors such as tissue factor and neoplastic pro-coagulant. PAI-1, the main inhibitor of the plasminogen activator pathway, is also produced by tumor cells. Still, tumor production of factors inhibiting the fibrinolytic system plays a role in hypercoagulability and may contribute to tumor angiogenesis. Regarding arterial thrombotic events, although there is no unanimity regarding the causal relationship between the pathologies, epidemiological data strongly suggest that this complication is more common in patients with cancer, compared to the population without the disease.

It is worth mentioning that lung cancer is the most common cause of cancer deaths in the world. It is possible that the high mortality from lung cancer is related, at least partially, to the higher incidence of thrombotic complications presented by these patients, compared to those with other types of cancer. Although VTE is one of the main causes of morbidity and mortality in cancer patients, the use of anticoagulants as primary prophylaxis is not routinely recommended.

The pathophysiological mechanisms involved in the increased risk of thromboembolic events in cancer patients, especially with lung cancer, which, as mentioned, present, in addition to the aggressiveness of the disease itself, a higher incidence of thrombotic events, are still little known. The main objective of this project is to contribute to a better understanding of the mechanisms involved in thrombotic events in the population with lung cancer, with clear therapeutic impacts.

This is a case-control study with groups differentiated by the presence or absence of NSCLC and matched by age, sex and presence or absence of smoking in the 6 months prior to inclusion. Patients diagnosed with NSCLC without prior treatment for the disease will be candidates for participation in the study.

The primary objective is to compare platelet aggregability by optical aggregometry assessed by the AggRAM® method in patients diagnosed with NSCLC, prior to any oncological treatment, in relation to a control group matched by sex, age and presence or absence of smoking in the previous 6 months. to inclusion Secondary objetives includes laboratorial test of inflammation, coagulation and subgroup analysis.

Inclusion criteria

• Patients > 18 years old;
• Confirmed diagnosis of non-small cell lung carcinoma in the case group; absence of history of any neoplasia for control group
• Agreement to sign the Free and Informed Consent Form

Exclusion criteria

• Anticoagulation in the last 30 days;
• Use of any antiplatelet agent in the last 30 days;
• Use of any non-steroidal anti-inflammatory drugs in the last 30 days;
• Known platelet dysfunction or platelets <100,000/mm3 or >450,000/mm3;
• Creatinine clearance by MDRD <30 ml/min/1.73 m2
• Eastern Cooperative Oncology Group Performance Status Scale (ECOG) >2
• Known coagulation disorder;
• Hematocrit less than 34% or greater than 55%