Lymph-vascular invasion at RP shows no predictive role in very high-risk prostate cancer

Lymph-vascular invasion (LVI) at radical prostatectomy was not predictive of cancer-specific mortality (CSM) in patients with very high-risk prostate cancer, thus failing to provide additional guidance over standard clinical and pathological features currently used in the clinic.¹

Research findings presented during the 2021 American Urological Association Annual Meeting showed that at 5 years post-prostatectomy, the CSM-rate was 11.2% in patients with LVI compared with 7.2% in patients without LVI (P = .03), and multivariate analysis showed that LVI was not an independent predictor of a worse CSM rate (HR, 1.071; P = .7366).

According to presenting author Ivan Rakic, recent research has shown that LVI at radical prostatectomy can have a detrimental impact on overall survival in patients with prostate cancer, regardless of their risk stratification. However, he added that, “The predictive performance of LVI in patients with very high-risk disease—where it could potentially serve as a guide for the necessity of multimodal treatment—has not yet been elucidated.”

Thus, Rakic and his coinvestigators examined the hypothesis of whether LVI can independently predict CSM among patients with very high-risk disease.

Overall, the study enrolled 2058 patients with cM0 prostate cancer who had been treated between 2001 and 2019 at 2 tertiary cancer centers. All patients had received radical prostatectomy with lymph node dissection.

Patients were considered to have high-risk disease as a result of having at least 2 of these adverse prognostic features: pathological Gleason 8 to 10, ≥pT3b stage disease, and/or nodal involvement (pN1). Most (86%) patients had pT3b disease. Three-fourths (75%) of patients had pN1 status, over half (59%) had LVI, and over two-thirds (69%) had Gleason 9 prostate cancer.

“Regression analysis tested the relationship between LVI and CSM after accounting for the following covariates: PSA, pathological tumor stage, Gleason grade, pathological nodal status, and surgical margin status,” said Rakic.

Although LVI failed to predict CSM, several other factors were found to be independent predictors of CSM, including Gleason score ≥8 (HR, 5.668; P <.0001), positive surgical margins (HR, 1.774; P =.02), pN1 (HR, 2.147; P = .003), and stage ≥pT3b (HR, 3.113; P =.008).

“Our findings highlight an important shortcoming for LVI in very high-risk patients and further show the prognostic value of widely accepted adverse disease characteristics,” said Rakic.

References

1. Rakic N, Rakic I, Keeley J, et al. Examining the predictive role of lymph-vascular invasion in patients with very high-risk prostate cancer. Presented during the 2021 American Urological Association Annual Meeting; September 10-13, 2021. PD19-12.