The Burden and Predictors of Venous Thromboembolic Diseases in Patients with Multiple Primary Malignancies

Background: Venous thromboembolism (VTE) represents a considerable burden on cancer patients' survival and quality of life, but this burden varies based on the patient's baseline characteristics and cancer-related factors. Although solid evidence on the predictors and effect of VTE in cancer patients exists.

Aim: To evaluate VTE rate, morbidity, and mortality to develop parameters that could predict VTEs and their associated mortality in patients with multiple primary malignancies (MPMs).

Method And Results: This was a retrospective cohort study that took place at King Abdulaziz Medical City, Riyadh, Kingdom of Saudi Arabia. Two hundred and forty-two patients with at least two biopsy-proven malignancies and had at least 3 months of follow-up after MPMs diagnosis were included. VTE was diagnosed in 14.5% of the cases, two-thirds of which were deep vein thrombosis. VTE was significantly associated with a higher mortality and worse survival. Predictors of VTE after MPMs diagnosis were a high ECOG performance status at MPMs diagnosis, a metastatic first primary malignancy, and ICU admission after MPMs diagnosis. Having a GI or hematological malignancy as the second primary malignancy, a high D-dimer at ICU admission, and palliative care referral were significantly associated with a higher mortality in patients who had VTE.

Conclusion: VTE was diagnosed in 14.5% of patients with MPMs and it significantly compromises their survival. We believe that these results might be of particular benefit since the phenomenon of MPMs is becoming more frequently encountered.