Simple yet (more?) effective. Venous thromboembolism risk assessment model for germ cell tumour patients receiving first-line chemotherapy

Background: Germ cell tumours (GCT) are highly curable malignancies. Venous thromboembolism (VTE) is a serious complication, needing better risk assessment models (RAM).

Aim: Identification of VTE incidence and risk factors in metastatic GCT patients starting first-line chemotherapy. Developing a RAM and comparing it to Khorana risk score (KRS) and Padua Prediction Score (PPS).

Material and methods: We retrospectively analysed GCT patients staged IS-IIIC. VTE risk factors were identified with logistic regression. Area under curve of receiver operating characteristic (AUC-ROC), Akaike and Bayesian Information Criteria (AIC, BIC) were calculated for the developed RAM, KRS and PPS.

Results: Among 495 eligible patients, VTE occurred in 69 (13.9%), including 40 prior to chemotherapy. Vein compression (OR: 8.96; 95% CI: 2.85-28.13; p < 0.001), clinical stage IIIB-IIIC (OR: 5.68; 95% CI: 1.82-17.70; p = 0.003) and haemoglobin concentration (OR for 1 g/dL decrease: 1.32; 95% CI: 1.03-1.67; p = 0.026) were significant in our RAM. KRS ≥ 3 (OR: 3.31; 95% CI: 1.77-6.20; p < 0.001), PPS 4-5 (OR: 3.06; 95% CI: 1.49-6.29; p = 0.002) and PPS > 5 (OR 8.05; 95% CI 3.79-17.13; p < 0.001) correlated with VTE risk. Diagnostic criteria (AUC-ROC, AIC, BIC) for the developed RAM, KRS and PPS were (0.885; 0.567; -1641), (0.588; 0.839; -1576) and (0.700; 0.799; -1585), respectively. In the numerical score, the optimal cut-off point for high-risk was ≥9, with sensitivity, specificity, positive and negative predictive value of 0.78, 0.77, 0.35 and 0.96, respectively.

Conclusions: Our RAM, based on vein compression, clinical stage and haemoglobin concentration proved superior to both KRS and PPS. VTE is frequent in GCT patients.