Fang Ming Deng

Paxillin mediates extranuclear and intranuclear signaling in prostate cancer proliferation

In prostate cancer, the signals that drive cell proliferation change as tumors progress from castration-sensitive (androgen-dominant) to castration-resistant states. While the mechanisms underlying this change remain uncertain, characterization of common signaling components that regulate both stages of prostate cancer proliferation is important for developing effective treatment strategies. Here, we demonstrate that paxillin, a known cytoplasmic adaptor protein, regulates both androgen- and EGF-induced nuclear signaling. We show that androgen and EGF promoted MAPK-dependent phosphorylation of paxillin, resulting in nuclear translocation of paxillin. We found nuclear paxillin could then associate with androgen-stimulated androgen receptor (AR). This complex bound AR-sensitive promoters, retaining AR within the nucleus and regulating AR-mediated transcription. Nuclear paxillin also complexed with ERK and ELK1, mediating c-FOS and cyclin D1 expression; this was followed by proliferation. Thus, paxillin is a liaison between extranuclear MAPK signaling and nuclear transcription in response to androgens and growth factors, making it a potential regulator of both castration-sensitive and castration-resistant prostate cancer. Accordingly, paxillin was required for normal growth of human prostate cancer cell xenografts, and its expression was elevated in human prostate cancer tissue microarrays. Paxillin is therefore a potential biomarker for prostate cancer proliferation and a possible therapeutic target for prostate cancer treatment.

Prebiopsy MRI and MRI-ultrasound Fusion–targeted Prostate Biopsy in Men With Previous Negative Biopsies: Impact on Repeat Biopsy Strategies

OBJECTIVEnTo report outcomes of magnetic resonance imaging (MRI)-ultrasound fusion-targeted biopsy (MRF-TB) and 12-core systematic biopsy (SB) over a 26-month period in men with prior negative prostate biopsy.nnnMATERIALS AND METHODSnBetween June 2012 and August 2014, 210 men presenting to our institution for prostate biopsy withxa0≥1 prior negative biopsy underwent multiparametric MRI followed by MRF-TB and SB and were entered into a prospective database. Clinical characteristics, maximum mpMRI suspicion scores (mSS), and biopsy results were queried from the database, and the detection rates of Gleasonxa0≥7 prostate cancer (PCa) and overall PCa were compared between biopsy techniques using McNemars test.nnnRESULTSnForty seven (29%) of 161 men meeting inclusion criteria (mean age, 65xa0±xa08xa0years; mean prostate-specific antigen, 8.9xa0±xa08.9) were found to have PCa. MRF-TB and SB had overall cancer detection rates (CDRs) of 21.7% and 18.6% (P = .36), respectively, and CDR for Gleason score (GS)xa0≥7 disease of 14.9% and 9.3% (P = .02), respectively. Of 26 men with GSxa0≥7 disease, MRF-TB detected 24 (92.3%) whereas SB detected 15 (57.7%; P < .01). Using UCSF-CAPRA criteria, only 1 man was restratified from low risk to higher risk based on SB results compared to MRF-TB alone. Among men with mSSxa0<4, 72% of detected cancers were low risk by UCSF-CAPRA criteria.nnnCONCLUSIONnIn men with previous negative biopsies and persistent suspicion of PCa, SB contributes little to the detection of GSxa0≥7 disease by MRF-TB, and avoidance of SB bears consideration. Based on the low likelihood of detecting GSxa0≥7 cancer and overall low-risk features of PCa in men with mSSxa0<4, limiting biopsy to men with mSSxa0≥4 warrants further investigation.

Re-evaluating the concept of “dominant/index tumor nodule” in multifocal prostate cancer

Prostate cancer (PCa) often presents as a multifocal disease with heterogeneity in Gleason score (GS) and genetic alterations. Dominant/index tumor nodule (DN), the largest nodule in a multifocal disease, is presumed to harbor the most aggressive biological behavior and therefore dictate the overall clinical behavior of PCa. In this study, we examined the pathological features of DN and re-evaluated the validity of the “DN” concept in multifocal PCa. A total of 201 consecutive radical prostatectomy specimens were totally submitted and examined. All independent cancer foci were recorded with prognostically important pathological parameters. Unifocal and multifocal disease was present in 25 (12.4xa0%) and 176 (87.6xa0%) cases, respectively. In 20 (11.3xa0%) multifocal cases, the highest GS, the largest tumor volume (TV), and extraprostatic extension (EPE) did not concur in the same tumor nodules. Non-DNs had a higher GS and EPE in 13 cases each and had both the highest GS and EPE in 5 cases. In the majority of multifocal prostate cancer (88.7xa0%), DNs have the highest GS and EPE. In these cases, DN is still a valid concept and can be used for assigning overall GS and procuring tissue for research. However, in a significant number of cases (11.3xa0%), the largest TV, the highest GS, and EPE did not concur in the same tumor nodules. In these cases, pathologists should de-emphasize the concept of DN. Instead, they should place the emphasis on the multifocal nature of the disease and document the pathological features of all independent tumor foci that have the largest TV, the highest GS, and EPE.

Diagnosis of "poorly formed glands" Gleason pattern 4 prostatic adenocarcinoma on needle biopsy: An interobserver reproducibility study among urologic pathologists with recommendations

Accurate recognition of Gleason pattern (GP) 4 prostate carcinoma (PCa) on needle biopsy is critical for patient management and prognostication. “Poorly formed glands” are the most common GP4 subpattern. We studied the diagnostic reproducibility and the quantitative threshold of grading GP4 “poorly formed glands” and the criteria to distinguish them from tangentially sectioned GP3 glands. Seventeen urologic pathologists were first queried for the definition of “poorly formed glands” using cases representing a spectrum of PCa glandular differentiation. Cancer glands with no or rare lumens, elongated compressed glands, and elongated nests were considered “poorly formed glands” by consensus. Participants then graded a second set of 23 PCa cases that potentially contained “poorly formed glands” with a fair interobserver agreement (&kgr;=0.34). The consensus diagnoses, defined as agreement by >70% participants, were then correlated with the quantitative (⩽5, 6 to 10, >10) and topographic features of poorly formed glands (clustered, immediately adjacent to, and intermixed with other well-formed PCa glands) in each case. Poorly formed glands immediately adjacent to other well-formed glands regardless of their number and small foci of ⩽5 poorly formed glands regardless of their location were not graded as GP4. In contrast, large foci of >10 poorly formed glands that were not immediately adjacent to well-formed glands were graded as GP4. Grading “poorly formed glands” is challenging. Some morphologic features are, however, reproducible for and against a GP4 diagnosis. This study represents an important step in standardization of grading of “poorly formed glands” based on quantitative and topographic morphologic features.

Localized cystic disease of the kidney: distinction from cystic neoplasms and hereditary polycystic diseases.

Cystic changes are common in both neoplastic and non-neoplastic kidney diseases. The most important diagnostic consideration is to rule out cystic neoplasms and hereditary polycystic kidney disease for patient management. Localized cystic disease of the kidney is a rare, nongenetic and nonprogressive cystic disease that may mimic cystic neoplasms or hereditary polycystic disease. However, reports in the literature on its pathologic characteristics are scarce, and most surgical pathologists are unfamiliar with this entity. We report the clinicopathologic characteristics of 9 such cases that mimicked renal neoplasms and were treated surgically. Nine patients, including 5 men and 4 women, had a mean age of 33.3 years (range, 18 to 56 y) at diagnosis. Two patients presented with gross hematuria. In the remaining 7 patients, localized cystic disease was discovered incidentally. None had a personal history of cystic disease of the kidney or other organs or a family history of cystic renal disease. On imaging studies, solitary multilocular cystic lesions were identified in all patients with a mean size of 2.9 cm (range, 0.8 to 6 cm). Of 7 patients with documented Bosniak classification, 4 lesions were class III, and 3 lesions were class II. Follow-up was available in 5 patients, with a mean follow-up time of 14.6 months (range, 5 to 31 mo). No cysts were observed in the ipsilateral and contralateral kidneys during follow-up. Partial and total nephrectomy was performed in 8 and 1 patient, respectively. Grossly, the cystic lesions were not discrete and merged imperceptibly with the adjacent renal parenchyma without a discrete margin or capsule. Microscopically, cystic lesions involved renal papillae in all cases, and the cystic space was continuous with dilated collecting ducts. Cysts were lined with cuboidal or flat epithelial cells identical to those lining the collecting ducts. Significant inflammation was absent. The surrounding renal parenchyma was normal. With this study, we hope to raise awareness among surgical pathologists of this rare cystic lesion in order to avoid potential misdiagnosis of this lesion as a cystic neoplasm or hereditary polycystic disease. We also presented a diagnostic algorithm for working up the renal cystic lesions.

Diagnosis of Gleason pattern 5 prostate adenocarcinoma on core needle biopsy: an interobserver reproducibility study among urologic pathologists.

Accurate recognition of Gleason pattern 5 (GP5) prostate adenocarcinoma on needle biopsy is critical as it is associated with disease progression and adverse clinical outcome. Despite important implications of this diagnosis, interobserver variation in the diagnosis of GP5 has not been adequately studied. Digital images of 66 prostate adenocarcinoma cases that potentially contained a GP5 component were distributed to 16 urologic pathologists who were asked to classify whether GP5 was present. Each image was initially classified into 1 of 4 morphologic subpatterns by 2 coauthors (R.B.S. and M.Z.): solid nests (15), comedocarcinoma (8), single cells and/or cords (35), and variant morphology (8). Additional features captured included: size (large: >20 cells, medium: 10 to 20 cells, and small: <10 cells) and distribution of nuclei (uniform vs. nonuniform) for nests pattern; intraluminal coagulative tumor necrosis, karyorrhectic debris, and amorphous material for comedocarcinoma pattern; and quantity (⩽5, 6 to 10, and >10) and distribution (clustered vs. intermixed with adjacent well-formed glands) for single cells/cords pattern. Interobserver reproducibility of a diagnosis of GP5 was assessed and the morphologic subpatterns and features were correlated with the consensus diagnosis (defined as 75% agreement). Interobserver reproducibility for overall diagnostic agreement was fair (&kgr;=0.376). Among subpatterns, comedocarcinoma had highest reproducibility (&kgr;=0.499), followed by variant morphology (&kgr;=0.443), single cells/cords (&kgr;=0.369), and nests (&kgr;=0.347). All cases with the following features achieved consensus for GP5: large nests regardless of nuclear distribution; coagulative necrosis with or without karyorrhectic debris; single cells/cords >10 or 6 to 10 in a cluster; and signet ring-like cells in single cells or within nests pattern. A majority of cases with the following features achieved consensus against GP5: medium-size nests; exclusive intraluminal amorphous material; single cells/cords ⩽5; and Paneth cell change. Remaining morphologic features did not reach consensus for or against GP5. A majority (86%) of participants would diagnose a small focus of GP5 only when it is present in >1 level. The diagnostic reproducibility of GP5 within certain morphologies was only fair among urologic pathologists. However, the diagnosis of GP5 was more reproducible when certain restrictive morphologic and quantitative criteria were applied. These findings suggest that additional studies are needed to find highly reproducible features of GP5 associated with documented aggressive clinical outcome.

Atypical intraductal cribriform proliferations of the prostate exhibit similar molecular and clinicopathologic characteristics as intraductal carcinoma of the prostate

Atypical intraductal cribriform proliferations of the prostate (AIP) are loose cribriform proliferations of luminal cells that exhibit greater architectural complexity and/or nuclear atypia than high-grade prostatic intraepithelial neoplasia (HGPIN), but lack the diagnostic criteria for intraductal carcinoma (IDC). The significance of AIP has not been formally established. We compared the clinical, morphologic, and immunohistochemical characteristics of AIP with classic IDC in 310 radical prostatectomy specimens that were received over an 18-month period. Of the 310 cases, 46 cases had AIP only (n=10), IDC only (n=6), or AIP coexisting with IDC (n=30). The ERG status of all 46 AIP/IDC cases was identical to the nearby acinar carcinoma, contrasted to just 3 cases of HGPIN (7%, P<0.01). The degree of uniform phosphatase and tensin homolog (PTEN) loss in 34 selected cases was identical in AIP and IDC (66.7%). No foci of HGPIN showed uniform PTEN loss; there was only 38% concordance of PTEN expression pattern between HGPIN and the nearby acinar carcinoma, unlike AIP and IDC (77% and 81%, respectively, P<0.01). AIP-associated and/or IDC-associated carcinoma (n=46) showed a higher stage and grade compared with acinar-only carcinoma (n=264, P<0.01). AIP-associated carcinoma had similar clinicopathologic features as IDC-associated carcinoma, including preoperative prostate-specific antigen, Gleason score, extraprostatic extension, seminal vesicle invasion, and lymph node metastasis (n=36, P>0.05). In conclusion, AIP shares similar ERG/PTEN immunoprofiles and exhibits similar clinical behavior as IDC, warranting immediate repeat biopsy when AIP is identified on biopsy, as is recommended in the most recent WHO Classification of Tumours of the Urinary System and Male Genital Organs, 2016.

Size-adjusted Quantitative Gleason Score as a Predictor of Biochemical Recurrence after Radical Prostatectomy

BACKGROUNDnThe risk of biochemical recurrence (BCR) following radical prostatectomy for pathologic Gleason 7 prostate cancer varies according to the proportion of Gleason 4 component.nnnOBJECTIVEnWe sought to explore the value of several novel quantitative metrics of Gleason 4 disease for the prediction of BCR in men with Gleason 7 disease.nnnDESIGN, SETTING, AND PARTICIPANTSnWe analyzed a cohort of 2630 radical prostatectomy cases from 1990-2007. All pathologic Gleason 7 cases were identified and assessed for quantity of Gleason pattern 4. Three methods were used to quantify the extent of Gleason 4: a quantitative Gleason score (qGS) based on the proportion of tumor composed of Gleason pattern 4, a size-weighted score (swGS) incorporating the overall quantity of Gleason 4, and a size index (siGS) incorporating the quantity of Gleason 4 based on the index lesion.nnnOUTCOME MEASUREMENTS AND STATISTICAL ANALYSISnAssociations between the above metrics and BCR were evaluated using Cox proportional hazards regression analysis.nnnRESULTS AND LIMITATIONSnqGS, swGS, and siGS were significantly associated with BCR on multivariate analysis when adjusted for traditional Gleason score, age, prostate specific antigen, surgical margin, and stage. Using Harrells c-index to compare the scoring systems, qGS (0.83), swGS (0.84), and siGS (0.84) all performed better than the traditional Gleason score (0.82).nnnCONCLUSIONSnQuantitative measures of Gleason pattern 4 predict BCR better than the traditional Gleason score.nnnPATIENT SUMMARYnIn men with Gleason 7 prostate cancer, quantitative analysis of the proportion of Gleason pattern 4 (quantitative Gleason score), as well as size-weighted measurement of Gleason 4 (size-weighted Gleason score), and a size-weighted measurement of Gleason 4 based on the largest tumor nodule significantly improve the predicted risk of biochemical recurrence compared with the traditional Gleason score.

Solid variant of papillary cystadenoma of the epididymis

Sir: Epididymal neoplasms, apart from adenomatoid tumour, are rare, mainly consisting of leiomyoma and papillary cystadenoma of the epididymis (PCE). PCE is a benign epididymal neoplasm, with only ~70 cases having been reported in the English-language literature to date. Most cases occur as slow-growing asymptomatic or painful nodules in the head of the epididymis; however, a few have been described in the broad ligaments and pelvic cavity of females. Some PCEs have been discovered during evaluation for infertility caused by azoospermia. PCE may occur sporadically or as a manifestation of von Hippel–Lindau disease (VHLD), an autosomal dominant tumour syndrome that results from a germline mutation in the VHL genes. Sporadic PCEs are more common and mostly unilateral, whereas VHLD-associated PCEs usually occur bilaterally. Some sporadic cases have also been shown to harbour acquired somatic VHL gene mutations. Both sporadic and VHLD-associated PCEs have a good prognosis: recurrence after complete excision or malignant transformation into a primary adenocarcinoma of the epididymis is rare. Studies of PCE, including the precursor lesion in patients with VHLD, have shown that PCE arises in the efferent ducts of the head of the epididymis (mesonephric origin). Microscopically, there are variable degrees of ductal ectasia, ranging from slight dilatation to microcyst or macrocyst formation. Papillary processes arise from the walls of the cysts, and may completely fill the cysts; however, an exclusive solid pattern without other classic patterns has not been reported in the literature. Cysts may also contain eosinophilic secretions. Microvascular proliferation is prominent in the stroma between the cysts. The cyst walls and papillae are lined by a single layer of cuboidal or columnar cells with clear or vacuolated cytoplasm. The nuclei are bland, and focally show a reverse polarity, defined by the apical polarization of the nuclei towards the luminal surface. However, many of these cytological features of PCE may be shared by clear cell renal cell carcinoma (RCC) or clear cell papillary RCC, which results in a major diagnostic challenge for PCE. In addition, clear cell RCC is also associated with VHLD. In rare cases, foci of a solid/nested growth pattern are found in PCE, similar to that of cerebellar haemangioblastoma, which is another manifestation of VHLD. The similarity in cytological features between PCE and these other tumour types therefore often necessitates immunohistochemical characterization for the differential diagnosis. Previous studies have shown that PCE has an immunohistochemical staining profile identical to that of clear cell papillary RCC, with the only difference being primary tumour location. In this report, we describe a rare case of PCE with an exclusive solid growth pattern and without cyst or papillary formation, and emphasize the importance of ancillary immunohistochemistry in establishing the correct diagnosis. The patient is a 39-year-old white male with a past medical history of colonic polyp and hernia repair. He came to our institution for evaluation of a slow-growing scrotal mass that was intermittently painful, as well as for evaluation of infertility with mild teratozoospermia. Colour Doppler ultrasound revealed a 13mm round, isoechoic, hyperaemic and solid lesion on the head of the left epididymis. The initial clinical impression was that the lesion most likely represented an inflamed sperm granuloma. Serum levels of gonadotropins and sex hormones were within normal ranges. The patient was treated with prednisone for presumed sperm granuloma, but without improvement. He then underwent a left partial inguinal epididymectomy to excise the mass. Histologically, the epididymal tumour was wellcircumscribed and encapsulated, with a brownishwhite, solid and homogeneous cut surface. The tumour cells were arranged in a solid and nested pattern, accompanied by a rich microvascular proliferation (Figure 1A,B). There was no capsular invasion or vascular invasion. The tumour cells had abundant clear cytoplasm and bland nuclei without prominent nucleoli (Figure 1B). No mitosis or tumour necrosis was seen within the lesion. Immunohistochemically, the tumour cells were diffusely and strongly positive for cytokeratin 7 (Figure 1C), carbonic anhydrase IX (Figure 1D), paired box protein 8 (PAX-8) (Figure 1E), and cytokeratin AE1/AE3 (data not shown), and negative for CD10, calretinin and Wilms tumour protein 1 (WT-1) (data not shown). Immunostains for CD34 (Figure 1F), CD31 and ERG (data not shown) highlighted the vascular hyperplasia between the tumour nests. On the basis of the solid growth pattern, bland cytological features, and characteristic immunohistochemical profile, we diagnosed the tumour as a solid variant of PCE. Because the tumour was unilateral and the patient had no stigmata of VHLC, we believe that this case most likely represented a sporadic PCE not related to VHLD. Genetic

TPL2 Is an Oncogenic Driver in Keratocanthoma and Squamous Cell Carcinoma

Squamous cell carcinoma (SCC) and keratoacanthoma (KA; SCC/KA) research has been hampered mainly by our lack of understanding the underlying genetic and epigenetic alterations associated with SCC/KA development, as well as the lack of animal models that faithfully recapitulate histopathologic features of human SCC/KA. Here, we show that TPL2 overexpression induced both cell transformation in immortalized human keratinocytes and SCC and KA-like cutaneous SCC (cSCC) development in mice. Mechanistically, activation of TPL2 downstream signaling pathways such as MEK/ERK MAPK, mTOR, NF-κB, and p38 MAPK leads to TPL2-mediated cell transformation in immortalized human keratinocytes and tumorigenesis in mice. Most importantly, TPL2 overexpression is required for iTPL2 TG-driven SCC and KA-like cSCC tumor maintenance, validating TPL2 as a possible drug target for the treatment of SCC/KA. Finally, we verified that TPL2 is overexpressed in human cutaneous metastatic SCC and KA clinical specimens compared with normal skin. Taken together, our results establish TPL2 as an oncogenic driver in SCC/KA development. Cancer Res; 76(22); 6712-22. ©2016 AACR.