Outcomes of Active Surveillance after Initial Surveillance Prostate Biopsy

Is active surveillance an appropriate approach to manage prostate cancer patients with Gleason Score 3+3 who met the criteria for active surveillance?

OBJECTIVE

Prostate cancer is one of the common malignant tumors in men worldwide. Nowadays it seems that Gleason Score 3+3 may not need definite treatment and some of the experts even ignore it as a cancer but we should be aware that in some patients with Gleason Score 3+3 there is a higher risk for harboring higher-grade cancer. We had done this study to evaluate patients with prostate cancer with Gleason Score 3+3 to determine the value of tumor volume in these cases.

MATERIAL AND METHODS

From September 2010 to October 2017, radical prostatectomy was done for 123 sequential patients with localized prostate cancer in two referral centers of Shahid Beheshti Medical University, Tehran, Iran, and 42 cases with Gleason Scores 3+3 which who were candidates for active surveillance were included in the study.

RESULTS

Thirty of 42 (71.4%) patients had significant tumor volumes (≥0/5 cm3). When tumor volume was less than 0.5 cm3, none of the patients had extra prostatic tumor extension. In patients with tumor volume greater than 0.5 cm3, two cases (6.6%) had extra prostatic extension, 4 cases (13.3%) had positive margins, four cases (13.3%) reactive lymph nodes and 16 cases (53.3%) perineural invasion.

CONCLUSION

We suggest that some patients with Gleason Score 3+3 have tumor volume >0.5 cm3 who are considered having significant cancer pathology and active surveillance may not be appropriate approach to manage all cases with Gleason Score 3+3.

Contemporary approach to active surveillance for favorable risk prostate cancer

The approach to favorable risk prostate cancer known as “active surveillance” was first described explicitly in 2002. This was a report of 250 patients managed with a strategy of expectant management, with serial prostate-specific antigen and periodic biopsy, and radical intervention advised for patients who were re-classified as higher risk. This was initiated as a prospective clinical trial, complete with informed consent, beginning in 2007. Thus, there are now 20 years of experience with this approach, which has become widely adopted around the world. In this chapter, we will summarize the biological basis for active surveillance, review the experience to date of the Toronto and Hopkins groups which have reported 15-year outcomes, describe the current approach to active surveillance in patients with Gleason score 3 + 3 or selected patients with Gleason score 3 + 4 with a low percentage of Gleason pattern 4 who may also be candidates, enhanced by the use of magnetic resonance imaging, and forecast future directions.

National Trends in Active Surveillance for Prostate Cancer: Validation of Medicare Claims-based Algorithms

OBJECTIVE

To better describe the real-world use of active surveillance. Active surveillance is a preferred management option for low-risk prostate cancer, yet its use outside of high-volume institutions is poorly understood. We created multiple claims-based algorithms, validated them using a robust clinical registry, and applied them to Medicare claims to describe national utilization.

MATERIALS AND METHODS

We identified men with prostate cancer from 2012-2014 in a 100% sample of Michigan Medicare data and linked them with the Michigan Urologic Surgery Improvement Collaborative (MUSIC) registry. Using MUSIC treatment assignment as the standard, we determined the performance of 8 claims-based algorithms to identify men on active surveillance. We selected 3 algorithms (the most sensitive, the most specific, and a balanced algorithm incorporating age and comorbidity) and applied them to a 20% national Medicare sample to describe national trends.

RESULTS

We identified 1186 men with incident prostate cancer and completely linked data. Eight algorithms were tested with sensitivity ranging from 23.5% to 88.2% and specificity ranging from 93.5% to 99.1%. We found that the use of surveillance for men with incident prostate cancer increased from 2007 to 2014, nationally. However, among all men in the population, there was a large decrease in the rate of prostate cancer diagnosis and an increased or stable rate in the use of active surveillance, depending on the algorithm used. Less than 25% of men on active surveillance underwent a confirmatory prostate biopsy.

CONCLUSION

We describe the performance of claims-based algorithms to identify active surveillance.

Curative Radiation Therapy at Time of Progression Under Active Surveillance Compared With Up-front Radical Radiation Therapy for Prostate Cancer

PURPOSE

To describe and compare outcomes in men with initially presumed indolent prostate cancer receiving definitive radiation therapy after active surveillance (AS) versus those in a risk-matched cohort undergoing up-front radiation therapy.

METHODS AND MATERIALS

Men prospectively enrolled in an AS program between 1992 and 2014 and subsequently undergoing curative radiation therapy (ie, image guided radiation therapy [IGRT] or low-dose-rate brachytherapy [LDR-BT]) were identified. Biochemical relapse-free rate (bRFR), metastasis-free rate (mFR), and overall survival (OS) were compared against a cohort of men treated up front, matched by age, clinical prognostic indices (risk group, prostate-specific antigen, cT category, Gleason score, percentage of involved biopsy cores), and radiation therapy modality.

RESULTS

Of 1070 patients in the AS registry, 200 underwent definitive radiation therapy (143 IGRT and 57 LDR-BT) after a median of 32.9 (interquartile range [IQR] 20.6-59.8) months on surveillance. Main reasons for treatment were grade and volume upgrading (57.5% and 26%, respectively). Median follow-up after radiation therapy was 4.9 (IQR 3.1-7.5) years. At 5 years the bRFR, mFR, and OS were, respectively, 97%, 99%, and 98.5%. No patient died of prostate cancer. Adequate risk-matching was confirmed in an independent cohort comprising 359 patients receiving up-front IGRT (71%) or LDR-BT (29%) and followed for a median of 9 (IQR 3.1-7.5) years. There was no difference in the disease-specific outcomes (bRFR, mFR) between the 2 cohorts (Gray's P value of .257 and .934, respectively). In multivariate analyses, timing of radical radiation therapy (deferred vs up-front) was not correlated to biochemical relapse or metastases occurrence.

CONCLUSIONS

Curative-intent radiation therapy (ie, dose-escalated IGRT or LDR-BT) after a period of AS renders excellent oncologic outcomes at 5 years. Deferring radical therapy after a period of AS does not seem to result in inferior oncologic outcomes compared with patients with similar risk characteristics undergoing up-front treatment.