Systematic ultrasound-guided saturation and template biopsy of the prostate: indications and advantages of extended sampling

OBJECTIVES

Prostate biopsy (PB) is the gold standard for the diagnosis of prostate cancer (PCa). However, the optimal number of biopsy cores remains debatable. We sought to compare contemporary standard (10-12 cores) vs. saturation (=18 cores) schemes on initial as well as repeat PB.

METHODS

A non-systematic review of the literature was performed from 2000 through 2013. Studies of highest evidence (randomized controlled trials, prospective non-randomized studies, and retrospective reports of high quality) comparing standard vs saturation schemes on initial and repeat PB were evaluated. Outcome measures were overall PCa detection rate, detection rate of insignificant PCa, and procedure-associated morbidity.

RESULTS

On initial PB, there is growing evidence that a saturation scheme is associated with a higher PCa detection rate compared to a standard one in men with lower PSA levels (<10 ng/ml), larger prostates (>40 cc), or lower PSA density values (<0.25 ng/ml/cc). However, these cut-offs are not uniform and differ among studies. Detection rates of insignificant PCa do not differ in a significant fashion between standard and saturation biopsies. On repeat PB, PCa detection rate is likewise higher with saturation protocols. Estimates of insignificant PCa vary widely due to differing definitions of insignificant disease. However, the rates of insignificant PCa appear to be comparable for the schemes in patients with only one prior negative biopsy, while saturation biopsy seems to detect more cases of insignificant PCa compared to standard biopsy in men with two or more prior negative biopsies. Very extensive sampling is associated with a high rate of acute urinary retention, whereas other severe adverse events, such as sepsis, appear not to occur more frequently with saturation schemes.

DISCUSSION

Current evidence suggests that saturation schemes are associated with a higher PCa detection rate compared to standard ones on initial PB in men with lower PSA levels or larger prostates, and on repeat PB. Since most data are derived from retrospective studies, other endpoints such as detection rate of insignificant disease - especially on repeat PB - show broad variations throughout the literature and must, thus, be interpreted with caution. Future prospective controlled trials should be conducted to compare extended templates with newer techniques, such as image-guided sampling, in order to optimize PCa diagnostic strategy.

What is the optimal definition of misclassification in patients with very low-risk prostate cancer eligible for active surveillance? Results from a multi-institutional series

BACKGROUND

The risk of unfavorable prostate cancer in active surveillance (AS) candidates is nonnegligible. However, what represents an adverse pathologic outcome in this setting is unknown. We aimed at assessing the optimal definition of misclassification and its effect on recurrence in AS candidates treated with radical prostatectomy (RP).

MATERIALS AND METHODS

Overall, 1,710 patients eligible for AS according to Prostate Cancer Research International: Active Surveillance criteria treated with RP between 2000 and 2013 at 3 centers were evaluated. Patients were stratified according to pathology results at RP: organ-confined disease and pathologic Gleason score ≤ 6 (group 1); organ-confined disease and Gleason score 3+4 (group 2); and non-organ-confined disease, Gleason score ≥ 4+3, and nodal invasion (group 3). Biochemical recurrence (BCR) was defined as 2 consecutive prostate-specific antigen (PSA) ≥ 0.2 ng/ml. Kaplan-Meier curves assessed time to BCR. Multivariable Cox regression analyses tested the association between pathologic features and BCR. Multivariable logistic regression analyses identified the predictors of adverse pathologic characteristics.

RESULTS

Overall, 926 (54.2%), 653 (33.0%), and 220 (12.9%) patients were categorized in groups 1, 2, and 3, respectively. Median follow-up was 32.2 months. The 5-year BCR-free survival rate was 94.2%. Patients in group 3 had lower BCR-free survival rates compared with those in group 1 (79.1% vs. 97.0%, P<0.001). No differences were observed between patients included in group 1 vs. group 2 (97.0% vs. 94.7%, P = 0.1). These results were confirmed at multivariable analyses and after stratification according to margin status. Older age and PSA density ≥ 10 ng/ml/ml were associated with higher risk of unfavorable pathologic characteristics (i.e., inclusion in group 3; all P<0.001).

CONCLUSIONS

Among patients eligible for AS treated with RP, only men with Gleason score ≥ 4+3 or non-organ-confined disease at final pathology were at increased risk of BCR. These individuals represent the real misclassified AS patients, who can be predicted based on older age and higher PSA density.

Rectal toxicity after intensity modulated radiotherapy for prostate cancer: which rectal dose volume constraints should we use?

BACKGROUND

To define rectal dose volume constraints (DVC) to prevent ⩾grade2 late rectal toxicity (LRT) after intensity modulated radiotherapy (IMRT) for prostate cancer (PC).

MATERIAL AND METHODS

Six hundred thirty-seven PC patients were treated with primary (prostate median dose: 78Gy) or postoperative (prostatic bed median dose: 74Gy (adjuvant)-76Gy (salvage)) IMRTwhile restricting the rectal dose to 76Gy, 72Gy and 74Gy respectively. The impact of patient characteristics and rectal volume parameters on ⩾grade2 LRT was determined. DVC were defined to estimate the 5% and 10% risk of developing ⩾grade2 LRT.

RESULTS

The 5-year probability of being free from ⩾grade2 LRT, non-rectal blood loss and persisting symptoms is 88.8% (95% CI: 85.8-91.1%), 93.4% (95% CI: 91.0-95.1%) and 94.3% (95% CI: 92.0-95.9%) respectively. There was no correlation with patient characteristics. All volume parameters, except rectal volume receiving ⩾70Gy (R70), were significantly correlated with ⩾grade2 LRT. To avoid 10% and 5% risk of ⩾grade2 LRT following DVC were derived: R40, R50, R60 and R65 <64-35%, 52-22%, 38-14% and 5% respectively.

CONCLUSION

Applying existing rectal volume constraints resulted in a 5-year estimated risk of developing late ⩾grade2 LRT of 11.2%. New rectal DVC for primary and postoperative IMRT planning of PC patients are proposed. A prospective evaluation is needed.

Metastasis-directed therapy of regional and distant recurrences after curative treatment of prostate cancer: a systematic review of the literature

CONTEXT

The introduction of novel imaging modalities has increased the detection of oligometastatic prostate cancer (PCa) recurrence, potentially justifying the use of a metastasis-directed therapy (MDT) with surgery or radiotherapy (RT) rather than a systemic approach.

OBJECTIVE

To perform a systematic review of MDT for oligometastatic PCa recurrence.

EVIDENCE ACQUISITION

This systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. We searched the Medline and Embase databases from 1946 to February 2014 for studies reporting on biochemical or clinical progression and/or toxicity or complications of MDT (RT or surgery). Reports were excluded if these end points could not be ascertained or separately analysed, or if insufficient details were provided. Methodological quality was assessed using an 18-item validated quality appraisal tool for case series.

EVIDENCE SYNTHESIS

Fifteen single-arm case series reporting on a total of 450 patients met the inclusion criteria. Seven studies were considered of acceptable quality. Oligometastatic PCa recurrence was diagnosed with positron emission tomography with coregistered computed tomography in most of the patients (98%). Nodal, bone, and visceral metastases were treated in 78%, 21%, and 1%, respectively. Patients were treated with either RT (66%) or lymph node dissection (LND) (34%). Adjuvant androgen deprivation was given in 61% of patients (n=275). In the case of nodal metastases, prophylactic nodal irradiation was administered in 49% of patients (n=172). Overall, 51% of patients were progression free 1-3 yr after salvage MDT, with most of them receiving adjuvant treatment. For RT, grade 2 toxicity was observed in 8.5% of patients, with one case of grade 3 toxicity. In the case of LND, 11% and 12% of grade 2 and grade 3 complications, respectively, were reported.

CONCLUSIONS

MDT is a promising approach for oligometastatic PCa recurrence, but the low level of evidence generated by small case series does not allow extrapolation to a standard of care.

PATIENT SUMMARY

We performed a systematic review to assess complications and outcomes of treating oligometastatic prostate cancer recurrence with surgery or radiotherapy. We concluded that although this approach is promising, it requires validation in randomised controlled trials.

Prognostic effect of neuroendocrine differentiation in prostate cancer: A critical review

BACKGROUND

The multiple pathways that are involved in neuroendocrine differentiation (NED) in prostate cancer (PCa) are poorly elucidated. Evidence suggests that several environmental triggers induce NED leading to the adaptation of PCa to its close environment to maintain cell proliferation. Nevertheless, there is conflicting evidence regarding the prognostic role of NED in PCa.

METHODS

In this review, we aimed to summarize all available data about NED and to assess the prognostic role of NED in disease progression and therapy resistance, and its role in routine clinical practice. This review was based on articles found through a PubMed literature search between 1993 and 2013. The study outcome measure was the effect of NED on oncologic outcomes at each PCa stage.

RESULTS

In total, 59 articles reporting on the effect of NED on oncologic outcomes have been selected. In clinical practice, immunostaining for NED markers could have interesting predictive value for assessing the oncologic outcomes in patients receiving androgen-deprivation therapy. Thus, patients with high NED burden may be candidates for more aggressive treatment strategies targeting NED pathways. Conversely, strong evidence is lacking concerning its potential independent prognostic value in hormone-naïve PCa.

CONCLUSIONS

Current published data are not sufficient to recommend the use of NE markers in routine practice, particularly at early PCa stage.

Surveillance or metastasis-directed Therapy for OligoMetastatic Prostate cancer recurrence (STOMP): study protocol for a randomized phase II trial

Background

Metastases-directed therapy (MDT) with surgery or stereotactic body radiotherapy (SBRT) is emerging as a new treatment option for prostate cancer (PCa) patients with a limited number of metastases (≤3) at recurrence – so called “oligometastases”. One of the goals of this approach is to delay the start of palliative androgen deprivation therapy (ADT), with its negative impact on quality of life. However, the lack of a control group, selection bias and the use of adjuvant androgen deprivation therapy prevent strong conclusions from published studies.

The aim of this multicenter randomized phase II trial is to assess the impact of MTD on the start of palliative ADT compared to patients undergoing active surveillance.

Methods/Design

Patients with an oligometastatic recurrence, diagnosed on choline PET/CT after local treatment with curative intent, will be randomised in a 1:1 ratio between arm A: active surveillance only and arm B: MTD followed by active surveillance. Patients will be stratified according to the location of metastasis (node vs. bone metastases) and PSA doubling time (≤3 vs. > 3 months). Both surgery and SBRT are allowed as MDT. Active surveillance means 3-monthly PSA testing and re-imaging at PSA progression. The primary endpoint is ADT-free survival. ADT will be started in both arms at time of polymetastatic disease (>3 metastatic lesions), local progression or symptoms. The secondary endpoints include progression-free survival, quality of life, toxicity and prostate-cancer specific survival.

Discussion

This is the first randomized phase 2 trial assessing the possibility of deferring palliative ADT with MDT in oligometastatic PCa recurrence.

Trial registration

Clinicaltrials.gov identifier: NCT01558427

Can we expand active surveillance criteria to include biopsy Gleason 3+4 prostate cancer? A multi-institutional study of 2,323 patients

OBJECTIVE

To test the expandability of active surveillance (AS) to Gleason score 3+4 cancers by assessing the unfavorable disease risk in a large multi-institutional cohort.

MATERIALS AND METHODS

We performed a retrospective analysis including 2,323 patients with localized Gleason score 3+4 prostate cancer who underwent a radical prostatectomy between 2005 and 2013 from 6 academic centers. We analyzed the rates of biopsy downgrading/upgrading and advanced stage in the overall cohort by employing standardized AS criteria (using biopsy Gleason score 3+4).

RESULTS

The final pathologic Gleason score was 3+3 = 6 in 8%, 3+4 = 7 in 67%, 4+3 = 7 in 20%, and 8 to 10 in 5% cases. The overall rate of unfavorable disease (upgrading or advanced stage or both) was 46%. In multivariable analysis, prostate-specific antigen (PSA) level>10 ng/ml, PSA density (PSAD) >0.15 ng/ml/g, clinical stage >T1, and>2 positive cores were predictors of unfavorable disease. According to the AS criteria used, the risk of unfavorable disease ranged from 30% to 42%. In patients without any risk factor (PSA level≤ 10 ng/ml, PSAD ≤ 0.15 ng/ml/g, T1c, and ≤ 2 positive cores), the unfavorable disease rate was 19%. The main limitations of this study are the retrospective design and nonstandardization of pathologic assessment between centers.

CONCLUSIONS

Approximately half of patients with biopsy Gleason score 3+4 cancer have unfavorable disease at final pathology. Nevertheless, expanding AS eligibility to these patients may be acceptable provided adherence to strict selection criteria leading to a<20% risk of unfavorable disease. Future tools for selection such as magnetic resonance imaging, early rebiopsy, and serum markers may be especially beneficial in this group of patients.

Hair-sparing whole brain radiotherapy with volumetric arc therapy in patients treated for brain metastases: dosimetric and clinical results of a phase II trial

Purpose

To report the dosimetric results and impact of volumetric arc therapy (VMAT) on temporary alopecia and hair-loss related quality of life (QOL) in whole brain radiotherapy (WBRT).

Methods

The potential of VMAT-WBRT to reduce the dose to the hair follicles was assessed. A human cadaver was treated with both VMAT-WBRT and conventional opposed field (OF) WBRT, while the subcutaneously absorbed dose was measured by radiochromic films and calculated by the planning system. The impact of these dose reductions on temporary alopecia was examined in a prospective phase II trial, with the mean score of hair loss at 1 month after VMAT-WBRT (EORTC-QOL BN20) as a primary endpoint and delivering a dose of 20 Gy in 5 fractions. An interim analysis was planned after including 10 patients to rule out futility, defined as a mean score of hair loss exceeding 56.7. A secondary endpoint was the global alopecia areata severity score measured with the “Severity of Alopecia Tool” (SALT) with a scale of 0 (no hair loss) to 100 (complete alopecia).

Results

For VMAT-WBRT, the cadaver measurements demonstrated a dose reduction to the hair follicle volume of 20.5% on average and of 41.8% on the frontal-vertex-occipital medial axis as compared to OF-WBRT. In the phase II trial, a total of 10 patients were included before the trial was halted due to futility. The EORTC BN20 hair loss score following WBRT was 95 (SD 12.6). The average median dose to the hair follicle volume was 12.6 Gy (SD 0.9), corresponding to a 37% dose reduction compared to the prescribed dose. This resulted in a mean SALT-score of 75.

Conclusions

Compared to OF-WBRT, VMAT-WBRT substantially reduces hair follicle dose. These dose reductions could not be related to an improved QOL or SALT score.

Repeated stereotactic body radiotherapy for oligometastatic prostate cancer recurrence

PURPOSE

To assess the outcome of prostate cancer (PCa) patients diagnosed with oligometastatic disease at recurrence and treated with stereotactic body radiotherapy (SBRT).

METHODS

Non-castrate patients with up to 3 synchronous metastases (bone and/or lymph nodes) diagnosed on positron emission tomography - computed tomography, following biochemical recurrence after local curative treatment, were treated with (repeated) SBRT to a dose of 50 Gy in 10 fractions or 30 Gy in 3 fractions. Androgen deprivation therapy-free survival (ADT-FS) defined as the time interval between the first day of SBRT and the initiation of ADT was the primary endpoint. ADT was initiated if more than 3 metastases were detected during follow-up even when patients were still asymptomatic. Secondary endpoints were local control, progression free survival (PFS) and toxicity. Toxicity was scored using the Common Terminology Criteria for Adverse Events.

RESULTS

With a median follow-up from time of SBRT of 2 years, we treated 50 patients with 70 metastatic lesions with a local control rate of 100%. The primary involved metastatic sites were lymph nodes (54%), bone (44%), and viscera (2%). The median PFS was 19 mo (95% CI: 13-25 mo) with 75% of recurring patients having ≤3 metastases. A 2nd and 3rd course of SBRT was delivered in 19 and 6 patients respectively. This results in a median ADT-FS of 25 months (20-30 mo). On univariate analysis, only a short PSA doubling time was a significant predictor for both PFS (HR: 0.90, 95% CI: 0.82 - 0.99) and ADT-FS (HR: 0.83; 95% CI: 0.71 - 0.97). Ten patients (20%) developed toxicity following treatment, which was classified as grade I in 7 and grade II in 3 patients.

CONCLUSION

Repeated SBRT for oligometastatic prostate cancer postpones palliative androgen deprivation therapy with 2 years without grade III toxicity.

Prognostic factors influencing prostate cancer-specific survival in non-castrate patients with metastatic prostate cancer

BACKGROUND

In non-castrate prostate cancer (PCa), the prognostic value of the number of metastases on prostate cancer-specific survival (PCSS) is not well studied.

METHODS

We retrospectively analyzed the medical records of 1,206 patients, referred for radiotherapy of the prostate (bed) following diagnosis of PCa. Distant metastases (nodal, skeletal, and/or visceral) developed in 121 patients following curative treatment, of which 80 with complete records were not castrated at time of metastasis. The treatment at time of metastases was androgen deprivation therapy (ADT; n = 22), active surveillance (n = 10) or metastasis-directed therapy (MDT; n = 48). Cox-regression analyses were used to examine the influence of different variables on PCSS.

RESULTS

The median follow-up from primary PCa treatment was 6.9 years with a median interval from diagnosis to first metastatic event of 4.1 year (range: 0.2-15 years). The primary site of metastases was limited to lymph nodes (48%), bone (39%), and viscera (1%) or a combination (12%). Median PCSS from diagnosis of noncastrate metastases was 6.6 years (95% confidence interval [CI], 5.6-7.7 years). A longer premetastatic PSA doubling time (DT) (hazard ratio [HR] 0.73; 95% CI: 0.57-0.92), a lower number of metastases at first presentation (HR 1.07; 95% CI: 1.02-1.12) and pattern of metastatic spread (HR 3.6; 95% CI: 1.13-11.8 for extensive vs. minimal) were associated with improved PCSS.

CONCLUSION

A longer PSA DT, involvement of nodes or axial skeleton and a lower number of metastases are associated with an improved PCSS in non-castrated patients developing metastases.

Intensity modulated radiotherapy induces pro-inflammatory and pro-survival responses in prostate cancer patients

Intensity modulated radiotherapy (IMRT) is one of the modern conformal radiotherapies that is widely used within the context of cancer patient treatment. It uses multiple radiation beams targeted to the tumor, however, large volumes of the body receive low doses of irradiation. Using γ-H2AX and global genome expression analysis, we studied the biological responses induced by low doses of ionizing radiation in prostate cancer patients following IMRT. By means of different bioinformatics analyses, we report that IMRT induced an inflammatory response via the induction of viral, adaptive, and innate immune signaling. In response to growth factors and immune-stimulatory signaling, positive regulation in the progression of cell cycle and DNA replication were induced. This denotes pro-inflammatory and pro-survival responses. Furthermore, double strand DNA breaks were induced in every patient 30 min after the treatment and remaining DNA repair and damage signaling continued after 18-24 h. Nine genes belonging to inflammatory responses (TLR3, SH2D1A and IL18), cell cycle progression (ORC4, SMC2 and CCDC99) and DNA damage and repair (RAD17, SMC6 and MRE11A) were confirmed by quantitative RT-PCR. This study emphasizes that the risk assessment of health effects from the out-of-field low doses during IMRT should be of concern, as these may increase the risk of secondary cancers and/or systemic inflammation.

Hypofractionated intensity-modulated arc therapy for lymph node metastasized prostate cancer: early late toxicity and 3-year clinical outcome

BACKGROUND AND PURPOSE

For patients with N1 prostate cancer (PCa) aggressive local therapies can be advocated. We evaluated clinical outcome, gastro-intestinal (GI) and genito-urinary (GU) toxicity after intensity modulated arc radiotherapy (IMAT)+androgen deprivation (AD) for N1 PCa.

MATERIAL AND METHODS

Eighty patients with T1-4N1M0 PCa were treated with IMAT and 2-3years of AD. A median dose of 69.3Gy (normalized isoeffective dose at 2Gy per fraction: 80Gy [α/β=3]) was prescribed in 25 fractions to the prostate. The pelvic lymph nodes received a minimal dose of 45Gy. A simultaneous integrated boost to 72Gy and 65Gy was delivered to the intraprostatic lesion and/or pathologically enlarged lymph nodes, respectively. GI and GU toxicity was scored using the RTOG/RILIT and RTOG-SOMA/LENT-CTC toxicity scoring system respectively. Three-year actuarial risk of grade 2 and 3/4 GI-GU toxicity and biochemical and clinical relapse free survival (bRFS and cRFS) were calculated with Kaplan-Meier statistics.

RESULTS

Median follow-up was 36months. Three-year actuarial risk for late grade 3 and 2 GI toxicity is 8% and 20%, respectively. Three-year actuarial risk for late grade 3-4 and 2 GU toxicity was 6% and 34%, respectively. Actuarial 3-year bRFS and cRFS was 81% and 89%, respectively. Actuarial 3-year bRFS and cRFS was, respectively 26% and 32% lower for patients with cN1 disease when compared to patients with cN0 disease.

CONCLUSION

IMAT for N1 PCa offers good clinical outcome with moderate toxicity. Patients with cN1 disease have poorer outcome.

Use of EORTC target definition guidelines for dose-intensified salvage radiation therapy for recurrent prostate cancer: results of the quality assurance program of the randomized trial SAKK 09/10

PURPOSE

Different international target volume delineation guidelines exist and different treatment techniques are available for salvage radiation therapy (RT) for recurrent prostate cancer, but less is known regarding their respective applicability in clinical practice.

METHODS AND MATERIALS

A randomized phase III trial testing 64 Gy vs 70 Gy salvage RT was accompanied by an intense quality assurance program including a site-specific and study-specific questionnaire and a dummy run (DR). Target volume delineation was performed according to the European Organisation for the Research and Treatment of Cancer guidelines, and a DR-based treatment plan was established for 70 Gy. Major and minor protocol deviations were noted, interobserver agreement of delineated target contours was assessed, and dose-volume histogram (DVH) parameters of different treatment techniques were compared.

RESULTS

Thirty European centers participated, 43% of which were using 3-dimensional conformal RT (3D-CRT), with the remaining centers using intensity modulated RT (IMRT) or volumetric modulated arc technique (VMAT). The first submitted version of the DR contained major deviations in 21 of 30 (70%) centers, mostly caused by inappropriately defined or lack of prostate bed (PB). All but 5 centers completed the DR successfully with their second submitted version. The interobserver agreement of the PB was moderate and was improved by the DR review, as indicated by an increased κ value (0.59 vs 0.55), mean sensitivity (0.64 vs 0.58), volume of total agreement (3.9 vs 3.3 cm(3)), and decrease in the union volume (79.3 vs 84.2 cm(3)). Rectal and bladder wall DVH parameters of IMRT and VMAT vs 3D-CRT plans were not significantly different.

CONCLUSIONS

The interobserver agreement of PB delineation was moderate but was improved by the DR. Major deviations could be identified for the majority of centers. The DR has improved the acquaintance of the participating centers with the trial protocol.

Early biomarkers related to secondary primary cancer risk in radiotherapy treated prostate cancer patients: IMRT versus IMAT

PURPOSE

To investigate whether rotational techniques (Volumetric Modulated Arc Therapy - VMAT) are associated with a higher risk for secondary primary malignancies compared to step-and-shoot Intensity Modulated Radiation Therapy (ss-IMRT). To this end, radiation therapy (RT) induced DNA double-strand-breaks and the resulting chromosomal damage were assessed in peripheral blood T-lymphocytes of prostate cancer (PCa) patients applying γH2AX foci and G0 micronucleus (MN) assays.

METHODS AND MATERIALS

The study comprised 33PCa patients. A blood sample was taken before start of therapy and after the 1st and 3rd RT fraction to determine respectively the RT-induced γH2AX foci and MN. The equivalent total body dose (D(ETB)) was calculated based on treatment planning data.

RESULTS

A linear dose response was obtained for γH2AX foci yields versus D(ETB) while MN showed a linear-quadratic dose response. Patients treated with large volume (LV) VMAT show a significantly higher level of induced γH2AX foci and MN compared to IMRT and small volume (SV) VMAT (p<0.01). Assuming a linear-quadratic relationship, a satisfactory correlation was found between both endpoints (R(2) 0.86).

CONCLUSIONS

Biomarker responses were governed by dose and irradiated volume of normal tissues. No significant differences between IMRT and rotational therapy inherent to the technique itself were observed.

An immobilized antibody targeting N-cadherin facilitates spread of N-cadherin-positive tumour cells

BACKGROUND

We investigated whether an antibody targeting N-cadherin facilitates the adhesion and spreading of N-cadherin-positive tumour cells under static conditions.

MATERIALS AND METHODS

Two human melanoma cell lines, HMB-2 and BLM, were selected for their presence and lack of expression of N-cadherin, respectively. In vitro adhesion experiments were performed in the presence of a monoclonal antibody targeting N-cadherin (GC-4) or a control (antibody to α-tubulin). Quantitative data from the spreading assays were calculated by converting the images obtained by fluorescence microscopy to binary images.

RESULTS

For HMB-2 cells, the average cell width was significantly larger in the presence of GC-4 vs. control at all measured time points, with the exception of the measurement at 70 minutes (p=0.051). No differences were observed between controls and GC-4 for BLM cells.

CONCLUSION

The adhesion and spread of N-cadherin-positive tumour cells can be facilitated by the presence of an immobilized antibody to N-cadherin.

Screening and early diagnosis of prostate cancer: an update

Screening for prostate cancer has become a main controversial topic. First the currently used screening tools, PSA (Prostate Specific Antigen) and DRE (Digital Rectal Examination) have a low accuracy in the prediction of prostate cancer. Second, the benefit of screening in reducing the prostate cancer related mortality was not uniformly shown in older screening studies and there was concern about the risk of overdiagnosis and over-treatment of insignificant prostate cancers. Very recently, 3 major prospective, randomized screening studies have been published. This paper aims to provide an overview how the performance of the current screening tools can be ameliorated and evaluates the recently published screening studies with practical considerations for future screening protocols.

Salvage stereotactic body radiotherapy for patients with limited prostate cancer metastases: deferring androgen deprivation therapy

BACKGROUND

We investigated whether repeated stereotactic body radiotherapy (SBRT) of oligometastatic disease is able to defer the initiation of palliative androgen deprivation therapy (ADT) in patients with low-volume bone and lymph node metastases.

PATIENTS AND METHODS

Patients with up to 3 synchronous metastases (bone and/or lymph nodes) diagnosed on positron emission tomography, following biochemical recurrence after local curative treatment, were treated with (repeated) SBRT to a dose of 50 Gy in 10 fractions. Androgen deprivation therapy-free survival (ADT-FS) defined as the time interval between the first day of SBRT and the initiation of ADT was the primary end point. ADT was initiated if more than 3 metastases were detected during follow-up even when patients were still asymptomatic or in case of a prostate specific antigen elevation above 50 ng/mL in the absence of metastases. Secondary end points were local control, clinical progression-free survival, and toxicity. Toxicity was scored using the Common Terminology Criteria for Adverse Events.

RESULTS

We treated 24 patients with a median follow-up of 24 months. Ten patients started with ADT resulting in a median ADT-FS of 38 months. The 2-year local control and clinical progression-free survival was 100% and 42%, respectively. Eleven and 3 patients, respectively, required a second and third salvage treatment for metachronous low-volume metastatic disease. No grade 3 toxicity was observed.

CONCLUSION

Repeated salvage SBRT is feasible, well tolerated and defers palliative ADT with a median of 38 months in patients with limited bone or lymph node PCa metastases.