Expression of the Calcium-Sensing Receptor on Normal and Abnormal Parathyroid and Thyroid Tissue.

INTRODUCTION: Current imaging techniques have several limitations in detecting parathyroid glands. We have investigated the calcium-sensing receptor (CaSR) as a potential target for specifically labeling parathyroid glands for radiologic detection. For accurate imaging it is vital that a large differential expression exists between the target tissue and adjacent structures. We sought to investigate the relative abundance of the CaSR in normal and abnormal parathyroid tissue, as well as normal and abnormal thyroid. METHODS: Existing clinical specimens were selected that represented a wide variety of pathologically and clinically confirmed malignant and benign thyroid and parathyroid specimens. Sections were stained for the CaSR using immunohistochemistry and scored for intensity and abundance of expression. (H score = intensity scored from 0 to 3 multiplied by the % of cells at each intensity. Range 0-300). RESULTS: All parathyroid specimens expressed the CaSR to a high degree. Normal parathyroid had the highest H score (271, s.d. 25.4). Abnormal parathyroid specimens were slightly lower but still much higher than normal thyroid (H score 38.3, s.d. 23.3). Medullary thyroid cancer also expressed the CaSR significantly higher than normal thyroid (H score 182, s.d. 69.1, P < 0.001) but below parathyroid levels. Hürthle cell carcinoma expressed the CaSR to a lesser degree but higher than normal thyroid (H score 101, s.d. 46.4, P = 0.0037). CONCLUSIONS: The CaSR is differentially expressed on parathyroid tissue making it a feasible target for parathyroid imaging. False positives might be anticipated with medullary and Hürthle cell cancers.

Less Is More: Evaluation of Gross Examination Protocol for Cystectomy Specimens Following Neoadjuvant Chemotherapy

OBJECTIVES: Neoadjuvant chemotherapy (NAC) confers a survival advantage for muscle-invasive bladder cancer and is now recommended for chemotherapy-eligible patients. NAC may result in absent gross tumor, and current cystectomy gross examination protocols do not specify approach for these cases. METHODS: We included cystectomies performed from 2010 to 2018, capturing a period pre- and post-NAC recommendations. Gross descriptions were reviewed and slides of patients who received NAC were evaluated for microscopic tumor, number of blocks with tumor, and location of those blocks. RESULTS: We identified 239 radical cystectomies for bladder cancer (147 NAC, 92 non-NAC). Gross lesions were not identified for 91 cases. NAC cases had more total blocks submitted (mean, 17.5) compared with non-NAC cases (mean, 16.6). More NAC cases had additional blocks submitted (20 cases) compared with non-NAC cases (2), which were more frequently additional random sections. Of 108 NAC cases with residual carcinoma, only 2 (1.9%) were upstaged on additional random sections. CONCLUSIONS: At our institution, NAC and non-NAC cases are grossed with similar numbers of initial blocks; however, NAC cases are more likely to submit additional sections of gross lesions and random bladder without significant changes in stage. Our data suggest current gross examination protocols are sufficient for NAC cystectomies.

Neoadjuvant pazopanib and molecular analysis of tissue response in renal cell carcinoma.

BACKGROUNDSurgery remains the frontline therapy for patients with localized clear cell renal cell carcinoma (ccRCC); however, 20%-40% recur. Angiogenesis inhibitors have improved survival in metastatic patients and may result in responses in the neoadjuvant setting. The impact of these agents on the tumor genetic heterogeneity or the immune milieu is largely unknown. This phase II study was designed to evaluate safety, response, and effect on tumor tissue of neoadjuvant pazopanib.METHODSccRCC patients with localized disease received pazopanib (800 mg daily; median 8 weeks), followed by nephrectomy. Five tumors were examined for mutations by whole exome sequencing from samples collected before therapy and at nephrectomy. These samples underwent RNA sequencing; 17 samples were available for posttreatment assessment.RESULTSTwenty-one patients were enrolled. The overall response rate was 8 of 21 (38%). No patients with progressive disease. At 1-year, response-free survival and overall survival was 83% and 89%, respectively. The most frequent grade 3 toxicity was hypertension (33%, 7 of 21). Sequencing revealed strong concordance between pre- and posttreatment samples within individual tumors, suggesting tumors harbor stable core profiles. However, a reduction in private mutations followed treatment, suggesting a selective process favoring enrichment of driver mutations.CONCLUSIONNeoadjuvant pazopanib is safe and active in ccRCC. Future genomic analyses may enable the segregation of driver and passenger mutations. Furthermore, tumor infiltrating immune cells persist during therapy, suggesting that pazopanib can be combined with immune checkpoint inhibitors without dampening the immune response.FUNDINGSupport was provided by Novartis and GlaxoSmithKline as part of an investigator-initiated study.

Outcome of radioiodine therapy in thyroid cancer patients with recent contrasted computed tomography.

OBJECTIVE: To document the outcome of radioiodine therapy (RIT) in differentiated thyroid cancer (DTC) patients with recent contrasted computed tomography (CCT). METHODS: Eighteen patients with DTC and recent thyroidectomy who underwent RIT within 90 days after a CCT were included. Disease status following RIT and whether the expected response to RIT was achieved were documented. Disease status was classified into one of three categories based on the patient's thyroglobuline level, radioiodine scan (RIS), and other imaging modalities: no evidence of disease (NED), microscopic residual disease (MRD), or gross residual disease (GRD). Expected response to RIT was based on the overall interpretation of the referring physicians of follow up thyroglobuline values, RIS findings and clinical assessment as reflected in progress notes. Follow-up stimulated thyroglobuline and (or) RIS was performed on average 10.8 months after RIT (median 12 months). The last progress note reviewed was on average 33.3 months after RIT (median 31 months). RESULTS: There were 12 patients with NED, two with MRD and four with GRD. Expected response to RIT was achieved in 17 patients. In one patient, the effectiveness of RIT could not be determined. CONCLUSION: RIT in postthyroidectomy setting can be successfully performed within 90 days after CCT. Further research is needed to confirm our findings.

Current Procedural Terminology Coding in an Academic Breast Pathology Service: An Illustration of the Undervaluation of Breast Pathology.

Many physicians share the perception that the work required to evaluate breast pathology specimens is undervalued by Current Procedural Terminology (CPT) codes. To examine this issue, we compared slide volumes from an equal number of breast and nonbreast specimens assigned 88305, 88307, or 88309 CPT codes during four 2.5-week periods over 1 year. For each specimen, a number of initial hematoxylin and eosin-stained sections (H&Es), preordered additional H&E sections (levels), H&E sections ordered after initial slide review (recuts), and specimen type were recorded. Slides associated with ancillary stains were not considered. In total, 911 breast and 911 nonbreast specimens, each assigned 88305 (n=580), 88307 (n=320), and 88309 (n=11) CPT codes, were compared. Breast 88305 specimens were mainly core biopsies and margins and generated 2.3 and 6.4 times the H&Es and recuts, respectively, than did nonbreast specimens (P<0.01). Breast 88307 specimens were mainly lymph nodes and lumpectomies and generated 1.8 times the total slides than did nonbreast specimens (P<0.01). Eleven modified radical mastectomies (88309) generated 2.1 times the total slides than nonbreast 88309 specimens (P<0.01). In total (n=911 in each cohort), breast specimens generated 1.9, 4.0, and 1.7 times the H&Es, recuts, and total slides (P<0.01) than did nonbreast specimens. At our academic institution, the slide volume for breast specimens is nearly twice that of similarly coded nonbreast specimens. These results have significant implications for workload management and assessing pathologist productivity, particularly in subspecialty practices.

Opinions and Practices of Lung Cancer Screening by Physician Specialty.

BACKGROUND In response to the National Lung Screening Trial, numerous professional organizations published guidelines recommending annual lung cancer screening with low-dose computed tomography (LDCT) for high-risk patients. Prior studies found that physician attitudes and knowledge about lung cancer screening directly impacts the number of screening exams ordered.METHODS In 2015, we surveyed 34 pulmonologists and 186 primary care providers (PCPs) to evaluate opinions and practices of lung cancer screening in a large academic medical center. We compared PCP and pulmonologist responses using t-tests and χ2 tests.RESULTS The overall survey response rate was 40% (39% for PCPs and 50% for pulmonologists). Pulmonologists were more likely than PCPs to report lung cancer screening as beneficial for patients (88.2% versus 37.7%, P < .0001) and as being cost-effective (47.1% versus 14.3%, P = .02). More pulmonologists (76%) reported ordering a LDCT for screening in the past 12 months compared to PCPs (41%, P = .012). Pulmonologists and PCPs reported similar barriers to referring patients for lung cancer screening, including patient costs (82.4% versus 77.8%), potential for emotional harm (58.8% versus 58.3%), high false positive rate (47.1% versus 69.4%), and likelihood for medical complications (47.1% versus 59.7%).LIMITATIONS Our results are generalizable to academic medical centers and responses may be susceptible to recall bias, non-response bias, and social desirability bias.CONCLUSION We found significant differences in opinions and practices between PCPs and pulmonologists regarding lung cancer screening referrals and perceived benefits. As lung cancer screening continues to emerge in clinical practice, it is important to understand these differences across provider specialty to ensure screening is implemented and offered to patients appropriately.

Phase II trial of palbociclib in patients with metastatic urothelial cancer after failure of first-line chemotherapy.

BACKGROUND: The majority of urothelial cancers (UC) harbor alterations in retinoblastoma (Rb) pathway genes that can lead to loss of Rb tumour suppressor function. Palbociclib is an oral, selective inhibitor of CDK 4/6 that restores Rb function and promotes cell cycle arrest. METHODS: In this phase II trial, patients with metastatic platinum-refractory UC molecularly selected for p16 loss and intact Rb by tumour immunohistochemistry received palbociclib 125 mg p.o. daily for 21 days of a 28-day cycle. Primary endpoint was progression-free survival at 4 months (PFS4) using a Simon's two-stage design. Next-generation sequencing including Rb pathway alterations was conducted. RESULTS: Twelve patients were enrolled and two patients (17%) achieved PFS4 with insufficient activity to advance to stage 2. No responses were seen. Median PFS was 1.9 months (95% CI 1.8-3.7 months) and median overall survival was 6.3 months (95% CI 2.2-12.6 months). Fifty-eight percent of patients had grade ≥3 hematologic toxicity. There were no CDKN2A alterations found and no correlation of Rb pathway alterations with clinical outcome. CONCLUSIONS: Palbociclib did not demonstrate meaningful activity in selected patients with platinum-refractory metastatic UC. Further development of palbociclib should only be considered with improved integral biomarker selection or in rational combination with other therapies.

Northern Italy in the American South: Assessing interobserver reliability within the Milan System for Reporting Salivary Gland Cytopathology.

BACKGROUND: The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) has been proposed to standardize salivary gland fine-needle aspiration (FNA) diagnoses. This study assessed salivary gland FNA results and risk of malignancy (ROM) rates at the University of North Carolina as well as the interobserver reliability (IOR) of the atypia of undetermined significance (AUS) and salivary gland neoplasm of uncertain malignant potential (SUMP) categories. METHODS: The electronic medical record was searched for FNA cases from 2010 to 2017 with subsequent surgical resections. Histologic diagnosis was used for gold-standard comparison. The original cytologic results were then converted into MSRSGC categories (nondiagnostic, nonneoplastic, AUS, benign neoplasm, SUMP, suspicious, and malignant). For the assessment of IOR, 23 cases were selected with enrichment for cases diagnosed as AUS (n = 11) or SUMP (n = 9). Six boarded cytopathologists and 1 cytopathology fellow assessed representative slides and provided an MSRSGC diagnosis for each case. Fleiss' κ coefficients were calculated to determine IOR. RESULTS: The ROM was 33% for both AUS and SUMP cases; however, the risk of neoplasia was 56% for AUS cases and 100% for SUMP cases. Fleiss' κ for the AUS category was 0.217 (P < .05), and Fleiss' κ for the SUMP category was 0.024 (P = .74). CONCLUSIONS: In this study assessing the IOR of MSRSGC categories, fair agreement and slight agreement were found for the AUS and SUMP categories, respectively. Observers preferentially used the AUS or benign neoplasm category for SUMP cases, perhaps because of unfamiliarity with SUMP as a diagnostic option. The initial adoption of a new reporting system will require a quality assessment to ensure that the system is reliable and useful for clinicians. Cancer Cytopathol 2018;126:390-6. © 2018 American Cancer Society.

Utility of fine-needle aspiration and core biopsy with touch preparation in the diagnosis of renal lesions.

BACKGROUND: Cytologic evaluation by fine-needle aspiration (FNA) and core biopsy (CB) with touch preparation (TP) is used in the diagnosis of renal lesions. METHODS: Consecutive image-guided FNA and CB, with or without TP, of renal lesions were reviewed. The cytology diagnoses were correlated with the radiology, surgical specimens, and clinical course. RESULTS: A total of 154 procedures (76 FNA, 17 FNA+CB, 46 CB+TP, 15 FNA+CB+TP) were performed for lesions with benign (21), malignant (123), or indeterminate (10) radiology. Specimen adequacy was satisfactory in 86% of FNAs (93 of 108), 95% of TPs (58 of 61), and 94% of CBs (73 of 78), and is statistically significant for CB with or without TP versus FNA (P = .045). In the subset with concerning radiology (n = 133), specimen adequacy was satisfactory in 83% of FNAs (72 of 87), 95% of TPs (58 of 61), and 94% of CBs (73 of 78) (P = .006 for CB ± TP versus FNA), and procedures were diagnostic in 79% of FNAs (69 of 87), 90% of 61 TPs (55 of 61) and 90% of CBs (70 of 78) (P = .02 for CB ± TP versus FNA). Renal cell carcinoma subtype was reported in 63% of FNA (19 of 30) versus 88% of CB ± TP (43 of 49) (P = .01), and Fuhrman nuclear grade was reported only on CB. The cytology diagnoses correlated with surgical specimens in 94% (33 of 35). The most common treatment was ablation of small (3.0 ± 1.3 cm) masses (n = 47). CONCLUSIONS: Compared with FNA, CB and TP have higher adequacy and diagnostic yield and provide more diagnostic information. Cytology diagnoses are highly accurate when correlated to surgical specimens.

Rapid on-site pathologic evaluation does not increase the efficacy of endobronchial ultrasonographic biopsy for mediastinal staging.

BACKGROUND: Endobronchial ultrasonography with transbronchial needle aspiration (EBUS-TBNA) has been shown to be equivalent to mediastinoscopy in lung cancer staging for mediastinal node involvement. Rapid on-site evaluation (ROSE) to determine the adequacy of nodal sampling has been claimed to be beneficial. METHODS: A retrospective evaluation was performed in 170 patients who underwent EBUS-TBNA from July 2008 to May 2011. The patients were classified as having either high or low pretest probability for mediastinal disease based on history and radiographic imaging. ROSE was compared with the final pathology reports based on slides and cell blocks. RESULTS: One hundred thirty-one (77%) patients were classified as being in the high pretest cohort based on clinical staging. Of these, 101 (77%) patients had adequate tissue sampling based on ROSE, with 70 (69%) patients having positive mediastinal disease. In the 30 (23%) patients who had inadequate tissue by ROSE, the final analysis of all the prepared slides and cell blocks allowed for a diagnosis in all but 8 patients. The sensitivity and specificity of ROSE in the high pretest probability cohort were 89.5% and 96.4%, respectively, whereas the overall sensitivity and specificity of EBUS-TBNA was 92.1% and 100%, respectively. Despite having inadequate tissue on ROSE in 30 of 131 patients, sufficient tissue was available on final analysis for diagnosis in 22 of 30 patients. CONCLUSIONS: ROSE does not impact clinical decision making if a thorough mediastinal staging using EBUS is performed. Despite inadequate tissue sampling assessment by ROSE, a final diagnosis was made in most patients, potentially avoiding an additional surgical procedure to prove mediastinal disease.

Comparison of ACINUS, caspase-3, and TUNEL as apoptotic markers in determination of tumor growth rates of clinically localized prostate cancer using image analysis.

BACKGROUND: The balance between apoptotic and proliferative processes determines the enlargement of a tumor. Accurate measurement of apoptotic and proliferative rates from diagnostic prostate biopsies would allow calculation of tumor growth rates in a population-based prostate cancer (CaP) study. Automated image analysis may be used if proliferation and apoptotic biomarkers provide clearly resolved immunostained images. METHODS: Clinical CaP aggressiveness was assigned as low, intermediate or high using clinical criteria for 46 research subjects with newly diagnosed CaP. Diagnostic biopsy sections from the research subjects were dual-labeled for proliferation biomarker, Ki-67 and apoptotic biomarker, apoptotic chromatin condensation inducer in the nucleus (ACINUS). Apoptotic biomarkers, caspase-3 and terminal deoxyribonucleotidyltransferase mediated dUTP-biotin nick end labeling (TUNEL) were labeled separately. Images from immunostained sections were analyzed using automated image analysis and tumor growth rates computed. Association between clinical CaP aggressiveness and tumor growth rates was explored. RESULTS: Sixteen subjects had high, 17 had intermediate, and 13 had low clinical CaP aggressiveness. Positive immunostaining was localized to the nucleus for Ki-67, ACINUS, and TUNEL. A statistically significant linear trend across clinical CaP aggressiveness categories was found when tumor growth rates were calculated using ACINUS (P = 0.046). Logistic regression and ROC plots generated showed ACINUS (AUC = 0.677, P = 0.048) and caspase-3 (AUC = 0.694, P = 0.038) to be better predictors than TUNEL (AUC = 0.669, P = 0.110). CONCLUSIONS: ACINUS met the criteria for automated image analysis and for calculation of apoptotic rate. Tumor growth rates determined using automated image analysis should be evaluated for clinical prediction of CaP aggressiveness, treatment response, recurrence, and mortality.

Use of the ThinPrep method in bile duct brushings: analysis of morphologic parameters associated with malignancy and determination of interobserver reliability.

Recent work suggests the ThinPrep method can improve diagnostic sensitivity and accuracy in bile duct brushings. However, the proportion of atypical and suspicious diagnoses remains high. The aim of this study was to identify the most useful morphologic features in ThinPrep bile duct cytology and evaluate interobserver reliability. We evaluated 100 bile duct brushings prepared by ThinPrep, all with either histology or long term clinical follow-up (55 malignant, 45 benign). Morphologic features were evaluated by four experienced cytopathologists blind to clinical information and follow-up diagnoses. These features included cellularity, blood or diathesis, mitoses, inflammation, three-dimensional groups, discohesive atypical cells, macronucleoli, well-defined cytoplasmic borders, and nuclear features of malignancy (nuclear membrance irregularity, chromatin clumping). The data were analyzed by intraclass correlation (ICC) and stepwise multiple logistic regression. Reviewers showed unanimous agreement in 29% of cases, one degree of disagreement in 58% of cases, and full disagreement in 13% of cases. Of benign cases, 38% were thought to be diagnostic of malignancy by at least one of the four reviewers. Sensitivity for the morphologic parameters varied from 18 to 67%; the highest sensitivity was for discohesive atypical cells, well-defined cytoplasmic borders, nuclear features of malignancy, and cellularity (67, 62, 51 and 46%, respectively). Specificity of parameters varied from 16 to 100%; the highest specificity was for mitoses, three-dimensional groups, nuclear features of malignancy, and macronucleoli (100, 98, 93, and 93%, respectively). Interobserver reliability (ICC) was very good for specimen cellularity (0.72) and nuclear features of malignancy (0.60). In logistic regression analysis, only nuclear features of malignancy and increasing patient age separated benign from malignant. On ThinPrep bile duct brushings, nuclear features of malignancy are most useful in distinguishing benign from malignant, and interobserver reliability for this parameter is very good. Discohesive atypical cells show moderate sensitivity and specificity, while three dimensional clusters and macronucleoli are specific but not sensitive for malignancy, and are not significant in multivariate logistic regression models. The relatively high proportion of benign cases thought to be diagnostic of malignancy by at least one reviewer argues for a consensus approach to this diagnosis.

Feasibility of constructing tissue microarrays from diagnostic prostate biopsies.

OBJECTIVES: The ability to construct prostate tissue microarrays (TMAs) using prostate needle biopsies could allow high throughput molecular profiling to search for prostate cancer prognostic biomarkers. MATERIALS AND METHODS: Diagnostic prostate biopsies from 13 patients (diagnosed 1996-2000) were obtained from the University of North Carolina (UNC) to construct one prostate TMA under uniform conditions. A second prostate TMA was attempted using diagnostic prostate biopsies from 45 patients (diagnosed 2004) obtained from the North Carolina-Louisiana Prostate Cancer Project (PCaP). RESULTS: Eleven men had sufficient prostate cancer in their diagnostic prostate biopsy blocks to construct a UNC TMA that yielded six-micron sections that provided an average of 76% of cores (maximum 99%) to a depth of 360 microm. Diagnostic prostate biopsy blocks from 35 PCaP research subjects were unsuitable for TMA construction as a result of no remaining prostate cancer in 4, insufficient prostate cancer in 9, and insufficient prostate tissue in 22. The PCaP TMA constructed from 10 men yielded an average of 37%, and a maximum of 45%, of cores when sectioned to a depth of 360 microm. CONCLUSIONS: TMAs may be constructed from diagnostic prostate biopsies obtained at an academic center under uniform conditions. However, excessive facing of blocks and the large number of re-cuts ordered by many community pathology laboratories deplete diagnostic prostate biopsy tissue. The experience of a population-based study of men with newly diagnosed prostate cancer in Louisiana and North Carolina suggests that TMAs may not be constructed using diagnostic prostate biopsies from men diagnosed with prostate cancer throughout the United States.

Detection of pre-invasive lung cancer: technical aspects of the LIFE project.

Lung cancer is the leading cause of cancer deaths in both men and women in the United States. The LIFE (Light Induced Fluorescence Endoscopy) Project was initiated at the University of North Carolina Medical Center in November, 1999, for the dual purposes of (1) detecting pre-invasive lung cancer in high-risk patients and (2) studying the molecular biology of pre-invasive lesions of the bronchus for possible development of molecular biomarkers. Of the 47 patients enrolled, all were current or former tobacco smokers, except for 1. Fluorescence endoscopy was utilized, in addition to white light bronchoscopy, to increase the detection of intraepithelial lesions. Adjacent biopsies were submitted for permanent and frozen sections, respectively, from four predetermined sites as well as from any abnormal areas. The snap-frozen specimens were cryostat sectioned, and the mucosal epithelial cells laser capture microdissected for DNA analysis. The great majority of specimens yielded sufficiently abundant and intact DNA to accomplish the molecular objectives. Histologic concordance of adjacent permanent and frozen sections was equivalent to the concordance of adjacent permanent sections, suggesting that frozen section diagnosis was adequate for the research purpose of correlating histology with molecular analysis.

Pathologic findings from the Breast Cancer Surveillance Consortium: population-based outcomes in women undergoing biopsy after screening mammography.

BACKGROUND: To the authors' knowledge, a comprehensive analysis of pathology outcomes after screening mammography, as it is practiced clinically in the U.S. general population, has not been performed. METHODS: Breast Cancer Surveillance Consortium data from 1996-2001 were used to identify pathology specimens that were obtained within 1 year of screening mammograms performed on 786,846 women ages 40-89 years. The pathology results were classified as invasive carcinoma, ductal carcinoma in situ (DCIS), or benign. The associations between overall pathology outcomes and invasive tumor size and lymph node status were analyzed by age and mammography assessment category. RESULTS: The rates of both recommending and performing a biopsy varied little with age. The 1,664,032 screening mammograms were followed by 26,748 known biopsies (1.6%) and 8815 diagnoses of breast carcinoma (0.53%). Overall, 81% of carcinomas were invasive, and 78% of those were pathologically lymph node-negative tumors, in contrast to the 66% prevalence observed in the Surveillance, Epidemiology, and End Results (SEER) data during the same period. Most invasive tumors measured between 0 mm and 10 mm (35%) or between 11 mm and 20 mm (36%) in greatest dimension, and 92% and 78% were lymph node-negative tumors, respectively: Biopsy results that were classified as malignant increased with age (P < 0.0001) and were most likely to follow Breast Imaging, Reporting, and Diagnosis System Category 5 and 4 assessments, respectively. Ductal hyperplasia (19.6%), fibroadenoma (18.5%), and other benign findings (56.1%) were the most common benign diagnoses. CONCLUSIONS: Pathologically negative lymph nodes were more prevalent in this mammographically screened population than in the overall SEER population. The prevalence of invasive carcinoma, DCIS, and benign findings presented herein establish a range of expected biopsy outcomes for women after screening mammography in the general U.S. population.

Gleason grading and volume estimation in prostate needle biopsy specimens: evolving issues.

The Gleason grading system for prostate cancer is a powerful tool that can help choose therapy and predict outcome for patients. The clinical use and problem areas of the Gleason grading system are reviewed. The issues discussed include grade discrepancies between prostate biopsy and resection specimens, grading small foci of tumor, diagnosing and grading cribriform lesions, reporting the grade when 3 grades of cancer are present in a specimen, and assignment of grade when multiple cores of differing grades are present. Finally, differing ways of communicating tumor volume and the percentage of high-grade carcinoma in prostate biopsy cores are considered.

Steroid 5alpha-reductase isozymes I and II in recurrent prostate cancer.

PURPOSE: Prostate cancer recurs during androgen deprivation therapy despite reduced circulating androgens. We showed that recurrent prostate cancer tissue has testosterone levels similar to androgen-stimulated benign prostate, whereas dihydrotestosterone levels were reduced 82% to 1.45 nmol/L, sufficient for androgen receptor activation. The altered testosterone/dihydrotestosterone ratio in recurrent prostate cancer suggests loss of 5alpha-reducing capability. The aim of this study was to characterize steroid 5alpha-reductase isozymes I (S5alphaRI) and II (S5alphaRII) in prostate tissues. EXPERIMENTAL DESIGN: A tissue microarray was constructed from 22 recurrent prostate cancer specimens and matched pairs of androgen-stimulated benign prostate and androgen-stimulated prostate cancer from 23 radical prostatectomy specimens. Immunoblots were constructed from eight recurrent prostate cancers, eight androgen-stimulated benign prostate, and eight androgen-stimulated prostate cancer specimens. Isozyme expression was examined in microarray sections and immunoblots using S5alphaRI and S5alphaRII polyclonal antibodies. Isozyme activities were measured in 12 recurrent prostate cancer, 12 androgen-stimulated benign prostate, and 12 androgen-stimulated prostate cancer specimens. RESULTS: Nuclear immunostaining exhibited higher S5alphaRI expression than S5alphaRII in recurrent prostate cancer, androgen-stimulated benign prostate, and androgen-stimulated prostate cancers (P < 0.0001); mean expression was 125, 150, and 115 for S5alphaRI versus 10, 29, and 37 for S5alphaRII, respectively. Cytoplasmic immunostaining was moderate and similar for both isozymes in the three tissue types (P > 0.05). Immunoblots confirmed immunohistochemistry; S5alphaRI was expressed in recurrent prostate cancer specimens and S5alphaRII was not detected. The activity of S5alphaRI (114.4 pmol/mg epithelial protein/minute) was 3.7-fold higher than S5alphaRII (30.7 pmol/mg epithelial protein/minute) in recurrent prostate cancer specimens. CONCLUSIONS: Expression levels and isozyme activity shifts from S5alphaRII toward S5alphaRI in recurrent prostate cancer. Dual inhibition of S5alphaRI and S5alphaRII should reduce dihydrotestosterone biosynthesis and may prevent or delay growth of recurrent prostate cancer.

Sampling strategy for prostate tissue microarrays for Ki-67 and androgen receptor biomarkers.

OBJECTIVE: To develop an optimal sampling strategy for tissue microarrays using automated digital analysis for androgen receptor (heterogeneous expression) and the cellular proliferation marker Ki-67 (homogeneous expression and evaluated by others using nonautomated methods). STUDY DESIGN: Tissue microarrays were constructed from 23 radical prostatectomy specimens and immunostained for androgen receptor expression and cellular proliferation. Automated digital image analysis was used, and the minimum number of cores necessary to capture variance change <3% was determined. Androgen receptor immunostaining was described by percent positive nuclei (PPN) and mean optical density (MOD). RESULTS: Androgen receptor PPN variance measurements showed that 5 cores should be obtained when a single block of a radical prostatectomy specimen contained cancer. If all of 15 blocks contained cancer, 2 cores should be obtained from each of 6 blocks. An optimal sampling strategy was developed for androgen receptor PPN, androgen receptor MOD and Ki-67 PPN. CONCLUSION: The selection of the number of cores to sample is a tradeoff between the number of cores available that contain cancer and the amount of work involved in the analysis. Sampling no fewer than 5 but no more than 12 cores per radical prostatectomy specimen can capture tissue heterogeneity.