Birgitte Grønkær Toft

ERG Protein Expression in Diagnostic Specimens Is Associated with Increased Risk of Progression During Active Surveillance for Prostate Cancer

BACKGROUND Compelling biomarkers identifying prostate cancer patients with a high risk of progression during active surveillance (AS) are needed. OBJECTIVE To examine the association between ERG expression at diagnosis and the risk of progression during AS. DESIGN, SETTING, AND PARTICIPANTS This study included 265 patients followed on AS with prostate-specific antigen (PSA) measurements, clinical examinations, and 10-12 core rebiopsies from 2002 to 2012 in a prospectively maintained database. ERG immunohistochemical staining was performed on diagnostic paraffin-embedded formalin-fixed sections with a ready-to-use kit (anti-ERG, EPR3864). Men were characterised as ERG positive if a minimum of one tumour focus demonstrated ERG expression. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Overall AS progression was defined as clinical progression: increased clinical tumour category ≥cT2b by digital rectal examination and ultrasound, and/or histopathologic progression: upgrade of Gleason score, more than three positive cores or bilateral positive cores, and/or PSA progression: PSA doubling time <3 yr. Risk of progression was analysed using multiple cause-specific Cox regression and stratified cumulative incidences (Aalen-Johansen method). Curatively intended treatment, watchful waiting, and death without progression were treated as competing events. RESULTS AND LIMITATIONS A total of 121 of 142 ERG-negative and 96 of 123 ERG-positive patients had complete diagnostic information. In competing risk models, the ERG-positive group showed significantly higher incidences of overall AS progression (p<0.0001) and of the subgroups PSA progression (p<0.0001) and histopathologic progression (p<0.0001). The 2-yr cumulative incidence of overall AS progression was 21.7% (95% confidence interval [CI], 14.3-29.1) in the ERG-negative group compared with 58.6% (95% CI, 48.7-68.5) in the ERG-positive group. ERG positivity was a significant predictor of overall AS progression in multiple Cox regression (hazard ratio: 2.45; 95% CI, 1.62-3.72; p<0.0001). The main limitation of this study is its observational nature. CONCLUSIONS In our study, ERG positivity at diagnosis can be used to estimate the risk of progression during AS. If confirmed, ERG status can be used to individualise AS programmes. PATIENT SUMMARY The tissue biomarker ERG identifies active surveillance patients with an increased risk of disease progression.

Handling of radical prostatectomy specimens: total or partial embedding?

Vainer B, Toft B G, Olsen K E, Jacobsen G K & Marcussen N
(2011) Histopathology58, 211–216
Handling of radical prostatectomy specimens: total or partial embedding?

Outpatient diagnostic of bladder tumours in flexible cystoscopes: Evaluation of fluorescence-guided flexible cystoscopy and bladder biopsies

Abstract Objective. The aim of this study was to evaluate photodynamic diagnosis (PDD) in flexible cystoscopes and the diagnostic quality of biopsies for diagnosis of non-muscle-invasive bladder cancer in the outpatients department (OPD). Material and methods. Seventy-three patients (aged 36–91 years) with recurrent non-muscle-invasive bladder cancer and a medium to high risk of recurrence had a flexible PDD cystoscopy performed in the OPD. The bladder was first examined in standard white light followed by PDD. Results. PDD was superior to white light diagnosis; PDD was positive in 16 patients (22%) where white light showed a normal bladder mucosa. Four of these patients had bladder tumour [4/73, 6%; two carcinoma in situ (CIS), two Ta]. The diagnosis was verified by transurethral resection of the bladder tumour in the operating room. In 20 patients (20/73, 27%) PDD identified additional tumour lesions that were not identified in white light (five CIS, 15 Ta). The false-positive detection rate of PDD was 0.41. False positivity was significantly reduced by simultaneous flex biopsies disproving malignancy. Biopsies were obtained from 57 patients and diagnosis of stage and grade were possible in 55 of these (97%). In two patients (4%) the tissue material was too small for diagnostic evaluation. Biopsies from 47 patients (83%) included muscularis mucosa and from 20 patients (35%) muscularis propria. In 30 patients all but one diagnosis from the OPD was confirmed by biopsy in rigid scopes in the operating room. Conclusions. PDD-guided cystoscopy and bladder biopsy in flexible cystoscopes can be performed in an OPD setting and with reliable results for diagnosis of tumour stage Ta, CIS and T1a bladder cancer.

Prostate needle biopsies: interobserver variation and clinical consequences of histopathological re-evaluation

Berg KD, Toft BG, Røder MA, Brasso K, Vainer B, Iversen P. Prostate needle biopsies: interobserver variation and clinical consequences of histopathological re‐evaluation. APMIS 2011; 119: 239–46.

Is it possible to predict low-volume and insignificant prostate cancer by core needle biopsies?

In an attempt to minimize overtreatment of localized prostate cancer (PCa) active surveillance (AS) and minor invasive procedures have received increased attention. We investigated the accuracy of pre‐operative findings in defining insignificant disease and distinguishing between unilateral/unifocal and bilateral/multifocal PCa. One‐hundred and sixty patients undergoing radical prostatectomy were included. Histology reports from the biopsies and matching prostatectomies were compared. Three definitions of insignificant cancer were used: InsigE: tumour volume ≤0.5 mL; InsigW: tumour volume ≤1.3 mL; InsigM: tumour ≤5% of total prostate volume and prostate‐specific antigen (PSA) ≤10 ng/mL. In all definitions, Gleason score (GS) was ≤6 and the tumour was organ confined. Biopsies alone performed poorly as a predictor of unifocal and unilateral cancer in the prostatectomy specimens with positive predictive values of 17.8% and 18.9% respectively. Inclusion of other clinical and biochemical parameters did not significantly increase the predictive value. However, the combination of GS ≤ 6, PSA ≤ 10 ng/mL and unifocal or unilateral cancer in biopsy cores resulted in a positive predictive value of 61.1%, 38.9% and 12.0%, respectively, for identifying InsigM, InsigW and InsigE in the prostate specimen. Conclusively, routine prostate biopsies cannot predict unifocal and unilateral PCa, and must be regarded insufficient to select patients for focal therapy. Although candidates for AS may be identified using standard biopsies, a considerable fraction of patients will be understaged. There is a need for more precise diagnostic tools to assess intraprostatic tumour growth.

The impact of the 2005 International Society of Urological Pathology consensus guidelines on Gleason grading – a matched‐pair analysis

To investigate whether the International Society of Urological Pathology (ISUP) 2005 revision of the Gleason grading system has influenced the risk of biochemical recurrence (BCR) after radical prostatectomy (RP), as the new guideline implies that some prostate cancers previously graded as Gleason score 6 (3 + 3) are now considered as 7 (3 + 4).

ERG protein expression over time: from diagnostic biopsies to radical prostatectomy specimens in clinically localised prostate cancer

Aims We evaluated the consistency in ERG protein expression from diagnostic specimens through rebiopsies to radical prostatectomies in patients with clinically localised prostate cancer to investigate the validity of ERG status in biopsies. Methods ERG expression was assessed by immunohistochemistry (IHC) in 625 biopsy sets and 86 radical prostatectomy specimens from 265 patients with prostate cancer managed on active surveillance. For IHC, a rabbit monoclonal primary antibody was used (clone: EPR3864). TMPRSS2-ERG fluorescence in situ hybridisation (FISH) analyses were performed in 74 biopsies using the FISH ZytoLight TriCheck Probe (SPEC ERG/TMPRSS2). FISH results were correlated with IHC findings. Results The concordance between FISH and IHC was 97.3% and IHC demonstrated a sensitivity and specificity for ERG rearrangement of 100% and 95.5%, respectively. Applying IHC, 38.1% of patients were ERG-positive, 53.6% were ERG-negative and 8.3% showed both ERG-positive and negative tumour foci (ERG heterogeneous) at diagnosis. When ERG status was dichotomised (ERG-positive or heterogeneous vs ERG-negative), 95.6%–97.1% of patients did not experience ERG reclassification during the first two rounds of rebiopsies. The concordance in ERG status between biopsies and surgical specimen was 89.5%–94.2% depending on the number of rebiopsies included. Sampling bias was assumed to explain most (81.3%) of the mismatches in ERG status. Conclusions Consistency in ERG status ranged from 90% to 95% for patients undergoing serial biopsies and radical prostatectomy. This indicates that biopsies can be used reliably to investigate ERGs prognostic and predictive value.

Risk factors associated with positive surgical margins following radical prostatectomy for clinically localized prostate cancer: can nerve-sparing surgery increase the risk?

Abstract Objective. The aim of this study was to evaluate the impact of preoperative and surgical parameters, including nerve-sparing technique, on the risk of positive surgical margins (PSM) following radical prostatectomy for clinically localized prostate cancer. Material and methods. A prospective consecutive single-institution Danish cohort of 1148 patients undergoing RP between 1995 and 2011 was investigated. To analyse the impact of covariates on risk of PSM, a multivariate logistic regression model was used, including cT category, biopsy Gleason score, prostate-specific antigen (PSA), percentage positive biopsies for cancer (PPB), surgeon and surgical technique. Results. The overall rate of PSM was 31.4%. The risk of PSM depended (p value for Wald χ 2 ) on PSA (p < 0.0001), PPB (p = 0.003), nerve-sparing surgery (p = 0.03) and the surgeon (p < 0.0001). For every doubling of PSA, the risk of PSM increased by 56%, beginning at 0.5 ng/ml [odds ratio (OR) = 1.56, 95% confidence interval (CI) 1.3–1.9, p < 0.01], and every 10% increase in PPB resulted in an 11% increased risk of PSM (OR = 1.11, 95% CI 1.0–1.2, p = 0.002). Two out of the six surgeons had a 50% reduction of risk of PSM compared to the referent surgeon. Nerve-sparing surgery increased the risk of PSM by 50% compared to wide resection (OR = 1.5, 95% CI 1.0–2.1, p = 0.03). Conclusion: Both preoperative and surgical parameters affect the risk of PSM after radical prostatectomy. Surgeon and high preoperative PSA, PPB and cT category were confirmed as predictors of PSM. Surprisingly, nerve-sparing surgery was independently associated with increased risk of PSM. The correct selection of candidates for nerve-sparing surgery remains unresolved.

A histopathological score on baseline biopsies from elderly donors predicts outcome 1 year after renal transplantation.

Toft BG, Federspiel BH, Sørensen SS, Bagi P, Nielsen HB, Andersen CB. A histopathological score on baseline biopsies from elderly donors predicts outcome 1 year after renal transplantation. APMIS 2012; 120: 182–6.

Germ Cell Neoplasia in Situ and Preserved Fertility Despite Suppressed Gonadotropins in a Patient With Testotoxicosis.

Context Testotoxicosis is an autosomal-dominant, male-limited disorder. Activating mutations in the luteinizing hormone receptor gene (LHCGR) cause high autonomous testosterone secretion, resulting in early-onset peripheral precocious puberty. Little is known about long-term consequences of testotoxicosis. Case Description We present a rare case of a patient followed for 25 years with two remarkable outcomes: preserved fertility and germ cell neoplasia in situ (GCNIS). He presented with precocious puberty at 10 months of age and was diagnosed with testotoxicosis due to a de novo heterozygous Asp578Tyr mutation in LHCGR. Testicular biopsy in childhood showed Leydig cell hyperplasia with altered cell maturation. From infancy throughout adulthood, elevated testosterone and estradiol, low inhibin B and anti-Müllerian hormone, and completely suppressed follicle-stimulating hormone and luteinizing hormone were noted. Height acceleration and advanced bone age resulted in a reduced final height. Semen analysis revealed ongoing spermatogenesis, and the patient fathered a child by natural conception. Ketoconazole treatment decreased circulating testosterone in childhood, supported by experimental suppression of testosterone production in his adult testis tissue cultured ex vivo. At 25 years of age, ultrasound revealed a testicular tumor, identified as a Leydig cell adenoma, but unexpectedly with GCNIS present in adjacent seminiferous tubules. Conclusion The case illustrates that absence of gonadotropins but high intratesticular testosterone concentration is sufficient for spermatogenesis and to allow fatherhood. Our study is also the first description, to our knowledge, of GCNIS in a patient with testotoxicosis. We recommend regular clinical examination and ultrasonic evaluation of the testes in these patients due to potential increased risk of malignancy.