Summary In this retrospective study, we investigated the influence of chemotherapy and immunotherapy on thromboembolic risk among United States Veterans with lung cancer during their first 6 months (180 days) following initiation of systemic therapy. Included patients received treatment with common front‐line agents that were divided into four groups: chemotherapy alone, immunotherapy alone, combination of chemo‐ and immunotherapies, and molecularly targeted therapies (control group). The cohort experienced a 7·4% overall incidence of thrombosis, but the analysis demonstrated significantly different rates among the different groups. We explored models incorporating multiple confounding variables as well as the competing risk of death, and these results indicated that both chemo‐ and immunotherapies were associated with an increased incidence of thrombosis, either alone or combined, compared with the control group (7·56%, P = 2.2 × 10–16; 10·2%, P = 2.2 × 10–16; and 7·87%, P = 2.4 × 10–14 respectively vs. 4·10%). The Khorana score was found to be associated with increased risk, as were vascular disease and metastases. We found an association between risk of thrombosis and the use of anticoagulation, accounting for several confounders, including history of thrombosis. Further study is warranted to better determine the drivers of thromboembolic risk and to identify ways to mitigate this risk for patients.

In this retrospective study, we investigated the influence of chemotherapy and immunotherapy on thromboembolic risk among US Veterans with lung cancer during their first six months of systemic therapy. Patients in the study cohort received treatment with common frontline agents that were divided into four groups: chemotherapy alone, immunotherapy alone, combination of chemo- and immunotherapies, and molecularly targeted therapies. The latter served as a control group of systemically treated lung cancer patients who received neither chemotherapy nor immunotherapy. The cohort experienced a 6.8% overall incidence of thromboembolic events with a median time to event of 49 days, but the analysis demonstrated significantly different rates among the different treatment groups. We explored models incorporating multiple confounding variables as well as the competing risk of death, and these results indicated that both chemotherapy and immunotherapy were associated with an increased incidence of thrombosis, either when given alone or combined, compared with the control group (6.91%, 9.09%, and 7.47% respectively versus 3.68%, p < 0.024). Both the Khorana score assessing thrombosis risk for cancer patients and the Charlson comorbidity score were found to be associated with increased risk of thrombosis in our analyses. Paradoxically, we found an association between risk of thrombosis and the use of prophylactic anticoagulation or aspirin during the first month of systemic treatment, accounting for several confounding variables including a patient's prior history of thrombosis. Additionally, our data suggest that thromboembolic events may occur more commonly in lung cancer patients treated with immunotherapy compared with chemotherapy. Further study is warranted to better determine the drivers of thromboembolic risk and to identify ways to mitigate this risk for patients.

between NCD terms of "Tumor Size" to T stage ("TNM_CLIN_T"). We also compared group stage ("TNM_Stage Group") to N stage (TNM_CLIN_N"), M stage ("TNM_CLIN_M"). We further assessed differences between "TNM_CLIN_M" and listed sites of metastatic disease as well as comparing whether Radiation administrations was concordant with given doses. Results: We evaluated the entire database with an initial size of N = 121,930 patients. After including only complete information only on TNM and tumor size criteria we evaluated concordance for 106262 patients. We noted marked discordant rates between T stage and Tumor size. Specifically, between tumors that were staged T1 did not meet correlate with their "Tumor Size" criteria in 12.5% of the time, T2 tumors did not meet size criteria in 8.5% of instances. Patients that were stage as M0 were only given a group stage of IV in 2.5% of instances while in 0.75% of instances was a group stage IV given when there was no identified metastatic site. For N stage, there was an error rate of approximately 2.6% between reported stage. With regard to "RAD Administered" there was a 1.7% error rate in dose being reported when it was listed that no radiation was administered. Conclusion: This demonstration serves to show that proper explanation of how the primary sample size is achieved is paramount. Depending on how one builds their data set (i.e., utilizing tumor size vs T1) could alter sample sizes and lead to the variance noted in NCDB studies evaluating similar questions. A comprehensive detailing of, or attachment of precise methodology can result in more overall transparency in analysis of large database oncology data.