Analysis of different tumor volume thresholds of insignificant prostate cancer and their implications for active surveillance patient selection and monitoring

Tumor Location and a Tumor Volume over 2.8 cc Predict the Prognosis for Japanese Localized Prostate Cancer

(1) Objective: Our study investigated the prognostic value of tumor volume and location in prostate cancer patients who received radical prostatectomy (RP). (2) Methods: The prognostic significance of tumor volume and location, together with other clinical factors, was studied using 557 patients who received RP. (3) Results: The receiver operating characteristic (ROC) curve identified the optimal cutoff value of tumor volume as 2.8 cc for predicting biochemical recurrence (BCR). Cox regression analysis revealed that a tumor in the posterior area (p = 0.031), peripheral zone (p = 0.0472), and tumor volume ≥ 2.8 cc (p < 0.0001) were predictive factors in univariate analysis. After multivariate analysis, tumor volume ≥ 2.8 cc (p = 0.0225) was an independent predictive factor for BCR. Among them, a novel risk model was established using tumor volume and location in the posterior area and peripheral zone. The progression-free survival (PFS) of patients who met the three criteria (unfavorable group) was significantly worse than other groups (p ≤ 0.001). Furthermore, multivariate analysis showed that the unfavorable risk was an independent prognostic factor for BCR. The prognostic significance of our risk model was observed in low- to intermediate-risk patients, although it was not observed in high-risk patients. (4) Conclusion: Tumor volume (≥2.8 cc) and localization (posterior/peripheral zone) may be a novel prognostic factor in patients undergoing RP.

The tumor volume after radical prostatectomy and its clinical impact on the prognosis of patients with localized prostate cancer

We evaluated the contribution of tumor volume (TV) to localized prostate cancer (PCa) patients’ prognosis. We retrospectively analyzed the data of 2394 patients who underwent radical prostatectomy (RP) for localized PCa. The effect of TV and tumor prostate ratio (TV/PV) on PCa patients' prognosis was analyzed through Kaplan–Meier and Cox-proportional analysis. The mean prostate volume for all patients was 36.5 ± 15.4 cc, and the mean TV was 5.9 ± 8.3 cc. A significant positive relationship was observed between the classification by risk group in D’ Amico risk classification and the National Comprehensive Cancer Network risk group (P < 0.001). The high TV showed significantly worse pathologic outcomes than the low TV in terms of high rates of extra-capsular extension, seminal vesicle invasion, and positive surgical margin (P < 0.05). The patients with high TV and TV/PV had significantly shorter biochemical recurrence-free survivals than those with low TV and TV/PV (P < 0.001). Finally, based on multivariate Cox-proportional analyses, TV and TV/PV was an independent predictor to predict shorter biochemical recurrence-free survival as both a TV (HR: 1.04, 95% CI 1.04–1.05, P < 0.001) and TV/PV (HR: 1.42, 95% CI 1.13–1.78, P = 0.003). TV was revealed to be an independent prognostic factor in the postoperative biochemical recurrence. Patients with a high number of positive core and longer tumor length were significantly related to higher TV.

Identification of candidates for observation

PURPOSE OF REVIEW

The clinical value of active surveillance may still be limited due to acceptance and considerable misclassification rates, and inadequate follow-up criteria. This review focuses on the most recent developments in the use of active surveillance and patient-specific factors that may be used to identify patients suitable for this strategy.

RECENT FINDINGS

The number of patients diagnosed with low-risk prostate cancer has risen. Active surveillance acceptance rates are increasing, but still limited and varying importantly (2-49%). Misclassification is inevitable in all currently used protocols, although most of these patients still have relatively favorable-risk prostate cancer. African-American race, obese, and older-aged patients show more unfavorable intermediate results in an active surveillance situation. These are unlikely to be explained by the small differences in preoperative characteristics only. Psychological profiling may also be added to the selection process. Most studies report intermediate endpoints only.

SUMMARY

Patient-specific factors may be incorporated when identifying patients for active surveillance. This does not imply that active surveillance is not justified in specific groups, but may suggest the need for an intensified and personalized selection, instead of a one-size-fits-all approach.