Integration of MRI to clinical nomogram for predicting pathological stage before radical prostatectomy

BACKGROUND

Debate persists regarding whether MRI should be used routinely for preoperative evaluation of prostate cancer.

OBJECTIVE

The aim is to assess the role of prostatic magnetic resonance imaging (MRI) and other preoperative data in extra-prostatic extension (EPE) evaluation.

PATIENTS AND METHODS

From 2000 to 2013, 1743 patients operated for radical prostatectomy had a preoperative MRI. Age, clinical stage with digital rectal exam (DRE), PSA, prostate weight, biopsy, MRI and pathological findings of the surgical specimen were noticed. A multiparametric score of the variables independently associated with EPE was built with or without MRI on a random sample test population and internally validated.

RESULTS

With mean age of 62.9 years and mean PSA of 9.6 ng/ml, the population was distributed as follows: 1424 DRE T1, 254 T2, 32 T3; on biopsy 990 Gleason score = 6 and 717 ≥ 7; on MRI 1322 iT2, 290 iT3A and 131 iT3B; on prostatectomy 15 pT0, 998 pT2, 548 pT3A, 181 pT3B and 1 pT4A. In multivariate analysis, DRE, PSA, Gleason score, prostate weight and MRI were independently associated with EPE and integrated in a score with an area under curve (AUC) of 0.74 [95% CI 0.71-0.77] (0.72 without MRI, p < 0.01) a positive predictive value of 61% and a negative predictive value of 74%, internally validated. The Hosmer-Lemeshow goodness-of-fit test showed good accuracy (p = 0.77).

CONCLUSIONS

Integration of MRI with clinical data for predicting pathological stage before radical prostatectomy permits to exclude accurately EPE in 74% of cases.

Extraprostatic extension into periprostatic fat is a more important determinant of prostate cancer recurrence than an invasive phenotype

PURPOSE

Although micrometastasis development correlates closely with the depth of invasion of many tumor types, it is unclear whether invasion into but not through the prostatic pseudocapsule has a negative impact on prognosis, similar to extraprostatic extension. We defined the impact of pseudocapsular invasion on the risk of post-prostatectomy biochemical recurrence.

MATERIALS AND METHODS

Patients with pT2-3a prostate cancer were identified from a prospectively recorded database. Those with pT2 disease were categorized according to pseudocapsular invasion presence or absence. The impact of pseudocapsular invasion on biochemical recurrence was determined by univariable and multivariable Cox regression analysis.

RESULTS

In a cohort of 1,338 patients we identified 595 with organ confined cancer positive for pseudocapsular invasion. Compared to tumors without evidence of invasion, pseudocapsular invasion was positively associated with higher Gleason grade and tumor volume (1.2 vs 1.9 cc, each p<0.001). On univariable analysis there was no difference in biochemical recurrence-free survival between patients with vs without pseudocapsular invasion, although those with extraprostatic extension had significantly lower biochemical recurrence-free survival (p<0.001). This was confirmed on multivariable analysis, which revealed that extraprostatic extension was a significant independent predictor of biochemical recurrence (HR 1.53, p=0.018). The presence of pseudocapsular invasion had no effect (HR 0.81, p=0.33).

CONCLUSIONS

Pseudocapsular invasion is not a pathological feature associated with an adverse outcome after prostatectomy. Thus, the depth of tumor invasion is not a continuum of risk and access to periprostatic adipose tissue is a more important determinant of disease behavior than an invasive phenotype.

Adjuvant and salvage radiotherapy after prostatectomy: AUA/ASTRO Guideline

PURPOSE

The purpose of this guideline is to provide a clinical framework for the use of radiotherapy after radical prostatectomy as adjuvant or salvage therapy.

MATERIALS AND METHODS

A systematic literature review using the PubMed®, Embase, and Cochrane databases was conducted to identify peer-reviewed publications relevant to the use of radiotherapy after prostatectomy. The review yielded 294 articles; these publications were used to create the evidence-based guideline statements. Additional guidance is provided as Clinical Principles when insufficient evidence existed.

RESULTS

Guideline statements are provided for patient counseling, the use of radiotherapy in the adjuvant and salvage contexts, defining biochemical recurrence, and conducting a re-staging evaluation.

CONCLUSIONS

Physicians should offer adjuvant radiotherapy to patients with adverse pathologic findings at prostatectomy (i.e., seminal vesicle invasion, positive surgical margins, extraprostatic extension) and should offer salvage radiotherapy to patients with prostatic specific antigen or local recurrence after prostatectomy in whom there is no evidence of distant metastatic disease. The offer of radiotherapy should be made in the context of a thoughtful discussion of possible short- and long-term side effects of radiotherapy as well as the potential benefits of preventing recurrence. The decision to administer radiotherapy should be made by the patient and the multi-disciplinary treatment team with full consideration of the patient's history, values, preferences, quality of life, and functional status. Please visit the ASTRO and AUA websites (http://www.redjournal.org/webfiles/images/journals/rob/RAP%20Guideline.pdf and http://www.auanet.org/education/guidelines/radiation-after-prostatectomy.cfm) to view this guideline in its entirety, including the full literature review.

Predictive factors of oncologic outcomes in patients who do not achieve undetectable prostate specific antigen after radical prostatectomy

PURPOSE

We identified factors predicting oncologic outcomes in cases of persistently detectable prostate specific antigen.

MATERIALS AND METHODS

We reviewed the charts of patients treated with radical prostatectomy between 1998 and 2011 at a total of 14 centers. Study inclusion criteria were radical prostatectomy for presumed localized prostate cancer, absent positive nodes and detectable prostate specific antigen, defined as prostate specific antigen 0.1 ng/ml or greater 6 weeks postoperatively. Of the 9,735 radical prostatectomy cases reviewed 496 (5.1%) were eligible for analysis. Predictive factors for oncologic outcomes were assessed in time dependent analyses using the Kaplan-Meier method and Cox regression models.

RESULTS

At 6 weeks prostate specific antigen was 0.1 to 6.8 ng/ml. Biochemical progression was noted in 74.4% of patients and clinical metastasis was noted in 5%. The 2 most powerful predictors of general salvage treatment (vs radiotherapy) were postoperative prostate specific antigen greater than 1 ng/ml (OR 3.46, p=0.032) and prostate specific antigen velocity greater than 0.2 ng/ml per year (HR 6.01, p=0.001). Positive prostate specific antigen velocity was the single factor that independently correlated with the risk of failed salvage therapy (HR 2.6, p=0.001). The 5-year disease-free survival rate was 81.0% in patients with stable or negative prostate specific antigen velocity compared with 58.4% in those with positive prostate specific antigen velocity (p<0.001).

CONCLUSIONS

Patients with detectable prostate specific antigen after radical prostatectomy have a poor biochemical outcome. We identified postoperative prostate specific antigen and prostate specific antigen velocity as independent predictors of progression and failed salvage treatment. In addition to pathological prognostic factors, these factors should be considered early to better stratify patients for adjuvant therapy.