Ex Vivo Fluorescence Confocal Microscopy (FCM) Ensures Representative Tissue in Prostate Cancer Biobanking: A Feasibility Study.

BACKGROUND: Biobanking of prostate carcinoma is particularly challenging due to the actual cancer within the organ often without clear margins. Frozen sections are to date the only way to examine the biobank material for its tumor content. We used ex vivo fluorescence confocal microscopy (FCM) to analyze biobank samples prior to cryoasservation. METHODS: 127 punch biopsies were acquired from prostatectomy-specimens from 40 patients. These biopsies were analyzed with a Vivascope 2500-G4 prior to their transfer to the biobank. In difficult cases, larger samples of the prostatectomy specimens were FCM scanned in order to locate tumor foci. After patient acquisition, all samples were taken from the biobank and analyzed. We compared the results of the FCM examinations with the results of conventional histology and measured the DNA content. RESULTS: With upstream FCM, the tumor content of biobank samples could be determined with high confidence. The detection rate of representative biobank samples was increased due to the rapid feedback. The biobank samples were suitable for further molecular analysis. CONCLUSION: FCM allows for the first time lossless microscopic analysis of biobank samples prior to their cryoasservation and guarantees representative tumor and normal tissue for further molecular analysis.

Hepatic Vasculopathy and Regenerative Responses of the Liver in Fatal Cases of COVID-19.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infects the nasopharynx and lungs and causes coronavirus disease-2019 (COVID-19). It may impact the heart, brain, kidney, and liver.1 Although functional impairment of the liver has been correlated with worse clinical outcomes, little is known about the pathophysiology of hepatic injury and repair in COVID-19.2,3 Histologic evaluation has been limited to small numbers of COVID-19 cases with no control subjects2,4 and demonstrated largely heterogeneous patterns of pathology.2,3.

Portal vein leiomyosarcoma: a case report and review of the literature.

BACKGROUND: Leiomyosarcoma of vascular smooth muscle is a very rare entity. A fair number of cases of vascular leiomyosarcomas have been reported, and the vast majority of these tumors arose from the inferior vena cava. CASE PRESENTATION: We report the case of a 71-year-old female patient who presented with recurrent upper abdominal pain. A CT-scan demonstrated a heterogenous mass in the liver hilum. Liver function tests and hematology parameters as well as the tumor markers were normal. Due to the unclear diagnosis a percutaneous biopsy of this mass was performed and revealed leiomyosarcoma. The patient was treated by a right sided hemihepatectomy with portal vein reconstruction and an end-to-side hepatico-jejunostomy. Final histology confirmed complete (R0) resection of a moderately differentiated leiomyosarcoma of the portal vein. After complete (R0) resection of the lesion, the patient remained without any signs of tumor recurrence for a total of 36 months until detection of an unresectable local recurrence. After surgical re-exploration the patient was finally referred to palliative radiotherapy. CONCLUSION: Vascular leiomyosarcoma of the portal vein is an extremely rare tumor entity. We have described a case with no evidence-based neo/adjuvant treatment options, where aggressive surgery achieved a tumor-free margin (R0), performed in a specialized center for sarcoma and hepatobiliary surgery.

Acetic acid compared with i-scan imaging for detecting Barrett's esophagus: a randomized, comparative trial.

BACKGROUND: Traditional surveillance in patients with Barrett's esophagus (BE) has relied on random biopsies. Targeted biopsies that use advanced imaging modalities may significantly improve detection of specialized columnar epithelium (SCE). OBJECTIVE: We compared the efficacy of targeted biopsies that used i-scan or acetic acid to random biopsies in the detection of SCE. DESIGN: Patients with visible columnar lined epithelium or known BE were randomized at a 1:1 ratio to undergo acetic acid application or i-scan with targeted biopsies. SETTING: Targeted biopsies were performed based on surface architecture according to the Guelrud classification followed by 4-quadrant biopsies. PATIENTS: A total of 95 patients were randomized. INTERVENTION: A total of 46 patients underwent acetic acid staining, and 49 underwent i-scan imaging. Random biopsies were performed in 86 patients. MAIN OUTCOME MEASUREMENTS: The primary outcome was the yield of SCE as confirmed by histologic assessment. RESULTS: The diagnostic yield for SCE was significantly higher with targeted biopsies than with random biopsies in both groups combined (63% vs 24%; P = .0001). The yield of targeted biopsies was significantly greater with both i-scan (66% vs 21%; P = .009) and acetic acid (57% vs 26%; P = .012) technologies and did not differ between these groups. The accuracy for predicting SCE was 96% (k = .92) for i-scan and 86% (k = .70) for acetic acid analysis. LIMITATIONS: No dysplastic lesions were found. CONCLUSION: The i-scan or acetic acid-guided biopsies have a significantly higher diagnostic yield for identifying SCE, with significantly fewer biopsies, as compared with a protocol of random biopsies. Acetic acid and i-scan showed comparable results diagnosing SCE in our study. ( CLINICAL TRIAL REGISTRATION NUMBER: NCT01442506.).

Hepatocellular carcinoma in Child's A cirrhosis: a retrospective analysis of matched pairs following liver transplantation vs. liver resection according to the intention-to-treat principle.

This is the first matched pair analysis on the puzzling clinical problem of whether to perform liver transplantation (LT) or liver resection (LR) for Child's A hepatocellular carcinoma (HCC) patients. A total of 201 patients diagnosed with HCC and Child's A liver cirrhosis were treated with LT transarterial chemoembolization (TACE) or LR between 1998 and 2012. To achieve the most accurate study design, two groups of 57 patients were matched retrospectively according to their tumor characteristics detected by the initial computerized tomography (CT) scan. Sixteen of 57 LT candidates were not transplanted due to tumor progress during pre-treatment (TACE). Nevertheless, the retrospective analysis of the matched pairs according to the intention-to-treat principle resulted in a better five-yr overall survival (OS) rate of 54.3% for the group of LT candidates compared with 35.7% for those receiving LR (p = 0.19). In patients meeting the University of California, San Francisco (UCSF) criteria, five-yr OS reached 58.4% after LT and 45.1% after LR (p = 0.56). For Milan criteria (MC) patients, LT resulted in 57.9% and LR in 42% five-yr OS rate (p = 0.29). In conclusion, the finding of a better OS rate in LT was not statistically significant. There was also a selection bias in favor of LT, which may have influenced the OS. Therefore, particularly in regard to organ scarcity, LR remains a viable treatment option for respectable HCC in Child's A cirrhosis.

Trends in epidemiology, treatment, and survival of hepatocellular carcinoma patients between 1998 and 2009: an analysis of 1066 cases of a German HCC Registry.

GOALS: The aim of this study was to analyze clinical presentation, course of disease, and management of patients with hepatocellular carcinoma (HCC) in a German referral center between 1998 and 2009. BACKGROUND: HCC is a rare tumor in Germany, but its incidence has increased over the last 30 years. New therapies such as chemoembolization with drug-eluting beads, selective internal radiotherapy, and sorafenib were introduced recently; however, the impact on clinical management and overall survival (OS) is unclear. STUDY: In this retrospective analysis, 1066 patients with HCC, separated into two 6-year periods (n=385; 1998 to 2003 and n=681; 2004 to 2009) were evaluated. RESULTS: The number of patients presenting each year (64 vs. 114 per year), with an age over 80 years or with nonalcoholic steatohepatitis increased significantly between periods. The main risk factors were alcoholic liver disease in 51.7%, chronic hepatitis C virus in 28.2%, and chronic hepatitis B virus in 13.4% of patients with liver cirrhosis and HCC. Patients presented with more advanced tumor stages and with worse liver function in period 2. The majority (61.6%) of patients received local treatment over a spectrum of Barcelona Clinic Liver-Cancer (BCLC) stages, whereas systemic therapy was offered to a minority (8.8%) and limited to BCLC stage C patients only. OS decreased in BCLC stage A and D and improved in BCLC stage B and C and decreased for all patients from 16.5 to 15.3 months between periods. CONCLUSIONS: No improvement of OS was observed when comparing time periods, partly because of the more advanced stage of HCC and because of the increasing age in the second time period. Improved and new therapeutic options and the intensification of surveillance programs are likely to increase survival of HCC patients in the future.

Ex Vivo Fluorescence Confocal Microscopy of MRI-Guided Targeted Prostate Biopsies for Rapid Detection of Clinically Significant Carcinomas-A Feasibility Study.

BACKGROUND: MRI-guided prostate biopsies from visible tumor-specific lesions (TBx) can be used to diagnose clinically significant carcinomas (csPCa) requiring treatment more selectively than conventional systematic biopsies (SBx). Ex vivo fluorescence confocal microscopy (FCM) is a novel technique that can be used to examine TBx prior to conventional histologic workup. METHODS: TBx from 150 patients were examined with FCM on the day of collection. Preliminary findings were reported within 2 h of collection. The results were statistically compared with the final histology. RESULTS: 27/40 (68%) of the csPCa were already recognized in the intraday FCM in accordance with the results of conventional histology. Even non-significant carcinomas (cisPCa) of the intermediate and high-risk groups (serum prostate-specific antigen (PSA) > 10 or 20 ng/mL) according to conventional risk stratifications were reliably detectable. In contrast, small foci of cisPCa were often not detected or were difficult to distinguish from reactive changes. CONCLUSION: The rapid reporting of preliminary FCM findings helps to reduce the psychological stress on patients, and can improve the clinical management of csPCa. Additional SBx can be avoided in individual cases, leading to lower rates of complications and scarring in the future surgical area. Additional staging examinations can be arranged without losing time. FCM represents a promising basis for future AI-based diagnostic algorithms.

How to decide about liver transplantation in patients with hepatocellular carcinoma: size and number of lesions or response to TACE?

BACKGROUND & AIMS: Liver transplantation is a curative treatment option for patients with hepatocellular carcinoma (HCC) and liver cirrhosis. To date, patient selection for transplantation is based on size and number of nodules as assessed by imaging before listing. We hypothesized that changes in tumour features resulting from pre-transplant transarterial chemoembolisation (TACE) is a superior criterion to predict tumour recurrence. METHODS: 136 patients with HCC in cirrhosis with two or more cycles of pre-transplant TACE were included in this study. According to the surgical specimens, 46 patients exceeded the Milan criteria. RESULTS: Tumour recurrence occurred in 21 patients (15%). Classification of Milan criteria according to the imaging at referral was not predictive for recurrence (p=0.58), whereas the Milan criteria in the imaging immediately before transplantation reflected changes after pre-transplant TACE and were highly predictive (p<0.0001). Of the 99 patients constantly within Milan or downstaged to within Milan, 88% were recurrence-free after 5 years, compared to 55% of the patients exceeding the Milan criteria despite pre-transplant TACE. Five-year absence of recurrence was better predicted by the criterion "Progressive Disease" according to RECIST (p<0.0001). If progression was defined as any progression (including less than 20% of the sum of target lesions or new measurable lesions), predictability of recurrence in the receiver operating characteristic was 0.86. CONCLUSIONS: Imprecise assessment of size and number of tumour lesions limits prognostic importance of initial imaging. Characteristics of tumour response to TACE are reliably recognized and allow identification of suitable patients for transplantation. Future selection criteria for LT in HCC should consider this aspect.

Cause of death during long-term follow-up for superficial esophageal adenocarcinoma.

BACKGROUND: The purpose of this study was to evaluate long-term prognosis and cause of death in patients with superficial esophageal adenocarcinoma (SEAC) after surgery. PATIENTS AND METHODS: A total of 85 patients without adjuvant or neoadjuvant treatment underwent surgery for SEAC (pT1N0-1, M0) 1984-2011. Medical records and causes of death were reviewed, and 79 specimens (93 %) were reanalyzed for cancer penetration. Survival was calculated according to Kaplan-Meier and comparisons of survival with log-rank test. Multivariate survival was analyzed with Cox proportional hazards model. RESULTS: Of 85 patients, 36 had transhiatal, 33 transthoracic en bloc, 6 minimally invasive en bloc, 5 vagal sparing esophageal resection and 5 endoscopic mucosal resections; 7 patients (8 %) had lymph node metastasis (LNM). Cancer penetration: 35 pT1a and 44 pT1b. Overall survival was 67 % at 5 years and 50 % at 10 years. Disease-specific survival was 82 % at 5 years and 78 % at 10 years. Recurrence-free survival was 80 % at 5 years. In a Cox multivariate model, poor overall survival was predicted only by LNM. Cumulative mortality during median follow-up of 5 years (0-25 years): 37 of 85 (44 %). Cause of death of these 37: SEAC recurrence for 15 (41 %), postoperative complications for 4 (11 %), another primary malignancy for 5 (14 %), non-cancer-related for 11 (30 %) and for 2 (5 %) cause unknown. Mortality after 5-year follow-up: 11 (30 %); 82 % of these deaths were unrelated to SEAC recurrence. CONCLUSIONS: With SEAC recurrence as the single most common cause of death, disease-specific 5-year survival was good. Overall and late (> 5-year) survival is affected by diseases related to aging.

Rectal cancer: assessment of response to neoadjuvant chemoradiation by dynamic contrast-enhanced MRI.

PURPOSE: To assess pretreatment functional and morphological tumor characteristics with magnetic resonance imaging (MRI) in advanced rectal carcinoma and to identify factors predicting response to neoadjuvant chemoradiation. MATERIALS AND METHODS: In a prospective study, 95 patients with rectal carcinoma underwent dynamic contrast-enhanced MRI before and after chemoradiation. Quantitative parameters were derived from a pharmacokinetic two-compartment model. Tumors were also characterized with regard to mucinous status at pretreatment high-resolution MRI as nonmucinous or mucinous. Response to treatment was defined as a downshift in the local tumor stage. RESULTS: The parameter k21 (contrast medium exchange rate) was higher at pretreatment MRI in nonmucinous compared with mucinous carcinomas (P < 0.001). The effect of chemoradiation on dynamic MR parameters was higher in nonmucinous carcinomas than in the mucinous subtype (P < 0.001). A higher rate of response to treatment was linked with nonmucinous morphology (P < 0.001). Multivariate analysis revealed an association between mucinous tumor morphology and poor response (odds ratio [95% confidence interval]: 0.113 [0.032-0.395], P < 0.001) as well as an association between a high 75th percentile of k21 and a higher response rate (odds ratio: 1.043 [1.001-1.086], P = 0.019). CONCLUSION: Functional and morphological parameters of pretreatment MRI can assess tumor characteristics associated with the effectiveness of chemoradiation before treatment initiation.

Metabolic syndrome and its association with fatty liver disease after orthotopic liver transplantation.

The metabolic syndrome (MetS) might contribute to morbidity after orthotopic liver transplantation (OLT). For this reason, we searched for MetS-associated risk factors and analyzed the link with nonalcoholic fatty liver disease (NAFLD) in OLT recipients. De novo MetS affected 32.9% of our cohort (n = 170) within 2 years after OLT. Multivariate analysis identified glycosylated hemoglobin (HbA1c) levels ≥5% [odds ratio (OR) = 3.5; 95% confidence interval (CI) = 1.56-8.13, P = 0.003], diabetes mellitus (OR = 4.31, CI = 1.69-10.99, P = 0.002), and arterial hypertension (OR = 4.59, CI = 1.46-14.49, P = 0.009) as independent risk factors for de novo MetS. MetS incidence correlated with steroid dosage after OLT (5.2 ± 2.4 mg/day vs. 7.1 ± 4.7 mg/day, P = 0.014), and was linked to NAFLD (P = 0.001) via obesity (OR = 4.67, CI = 1.55-14.1, P = 0.006) and dyslipidemia (OR = 4.23, CI = 1.35-13.3, P = 0.013) post-OLT. In conclusion, we were able to identify low threshold HbA1c as a novel risk factor for MetS after OLT and described a link of MetS with NAFLD in transplant organs. This study also indicated that steroid treatment is associated with MetS rates after OLT.

MRI-Guided Targeted and Systematic Prostate Biopsies as Prognostic Indicators for Prostate Cancer Treatment Decisions.

The standard procedure for the diagnosis of prostate carcinoma involves the collection of 10-12 systematic biopsies (SBx) from both lobes. MRI-guided targeted biopsies (TBx) from suspicious foci increase the detection rates of clinically significant (cs) PCa. We investigated the extent to which the results of the TBx predicted the tumor board treatment decisions. SBx and TBx were acquired from 150 patients. Risk stratifications and recommendations for interventional therapy (prostatectomy and radiotherapy) or active surveillance were established by interdisciplinary tumor boards. We analyzed how often TBx alone were enough to correctly classify the tumors as well as to indicate interventional therapy and how often the findings of SBx were crucial for therapy decisions. A total of 28/39 (72%) favorable risk tumors were detected in TBx, of which 11/26 (42%) very-low-risk tumors were not detected and 8/13 (62%) low-risk tumors were undergraded. A total of 36/44 (82%) intermediate-risk PCa were present in TBx, of which 4 (9%) were underdiagnosed as a favorable risk tumor. A total of 12/13 (92%) high-risk carcinomas were detected and correctly grouped in TBx. The majority of csPCa were identified by the sampling of TBx alone. The tumor size was underestimated in a proportion of ISUP grade 1 tumors. Systematic biopsy sampling is therefore indicated for the next AS follow-up in these cases.

Rectal Cancer: MR imaging of the mesorectal fascia and effect of chemoradiation on assessment of tumor involvement.

PURPOSE: To evaluate the impact of chemoradiation on the reliability of MRI in assessing tumor involvement of the mesorectal fascia in patients with rectal cancer. MATERIALS AND METHODS: Presurgical MRI was performed in 150 patients; among them 85 had received neoadjuvant long-course chemoradiation. A standardized imaging protocol (1.5 Tesla [T] system, image voxel size 0.6 × 0.4 × 3 mm(3) ), standardized surgery, and histopathological examination were applied for the entire patient population. Images were analyzed to identify potential tumor involvement of the mesorectal fascia (minimum tumor distance to fascia ≤1 mm) and compared with histopathology as the reference standard. Results of nonirradiated and irradiated patients were compared to define the impact of chemoradiation on imaging reliability. RESULTS: In nonirradiated patients, MRI was reliable in predicting or excluding tumor involvement of the mesorectal fascia, positive predictive value 80%, negative predictive value 89%. The frequency of overestimating tumor involvement was significantly higher in irradiated patients (P = 0.005, positive predictive value 42%). CONCLUSION: Discussions about MRI assessment of tumor involvement of the mesorectal fascia as a basis for recommending neoadjuvant chemoradiation should focus on investigations that excluded irradiated patients, because MRI is less reliable after chemoradiation and tends to overestimate mesorectal tumor involvement.

Prognostic factors and outcomes of patients with hepatocellular carcinoma in non-cirrhotic liver.

OBJECTIVES: To report the outcome of patients with hepatocellular carcinoma (HCC) in non-cirrhotic liver depending on the mode of primary treatment and to define clinicopathological factors influencing patients' prognosis. METHODS: A retrospective analysis of an unselected cohort of 105 patients was performed. Overall survival (OS) was estimated by the Kaplan-Meier method and potentially prognostic factors were analyzed in Cox regression models. RESULTS: OS of the whole cohort at 1, 3, and 5 years was 66%, 47%, and 29%, respectively. Tobacco consumption, ECOG >0, macroscopic vascular invasion, continuous tumor diameter, and treatment other than resection were predictors of decreased OS in the whole cohort. Resection was performed in 64% of patients with 1-, 3-, and 5-year OS rates of 84%, 69%, and 42%, respectively. Siderosis and BCLC stage were associated with decreased OS after resection. Recurrence occurred in 57% of patients with 1-, 3-, and 5-year disease-free survival (DFS) rates of 63%, 39%, and 31%, respectively. Viral hepatitis and macroscopic vascular invasion were associated with decreased DFS. One-, 3-, and 5-year OS rates in patients with non-surgical approaches (transarterial chemoembolization, systemic therapy, best supportive care) were 38%, 11%, and 7%, respectively. Tobacco consumption and Okuda stage were associated with decreased OS in these patients. CONCLUSIONS: OS and DFS of patients with HCC in non-cirrhotic liver depend most notably on tumor-related, demographic, and etiological factors. Features of the non-neoplastic liver tissue play only a minor role. Liver resection leads to a significantly better prognosis than non-surgical treatment approaches.

Ex Vivo Fluorescence Confocal Microscopy (FCM) of Prostate Biopsies Rethought: Opportunities of Intraoperative Examinations of MRI-Guided Targeted Biopsies in Routine Diagnostics.

BACKGROUND: The diagnosis of prostate carcinoma (PCa) requires time- and material-consuming histopathological examinations. Ex vivo fluorescence confocal microscopy (FCM) can detect carcinoma foci in diagnostic biopsies intraoperatively. METHODS: MRI-guided and systematic biopsies were identified in a dataset of our previously published study cohort. Detection rates of clinically relevant tumors were determined in both groups. A retrospective blinded trial was performed to determine how many tumors requiring intervention were detectable via FCM analysis of MRI-guided targeted biopsies alone. RESULTS: MRI-guided targeted biopsies revealed tumors more frequently than systematic biopsies. Carcinomas in need of intervention were reliably represented in the MRI-guided biopsies and were identified in intraoperative FCM microscopy. Combined with serum PSA levels and clinical presentation, 91% of the carcinomas in need of intervention were identified. CONCLUSIONS: Intraoperative FCM analysis of MRI-guided biopsies is a promising approach for the efficient diagnosis of PCa. The method allows a timely assessment of whether a tumor disease requiring intervention is present and can reduce the psychological stress of the patient in the waiting period of the histological finding. Furthermore, this technique can lead to reduction of the total number of biopsies needed for the diagnosis of PCa.

Ex Vivo Fluorescence Confocal Microscopy in Specimens of the Liver: A Proof-of-Concept Study.

Ex vivo Fluorescence Confocal Microscopy (FCM) is a technique providing high-resolution images of native tissues. The method is increasingly used in surgical settings in areas of dermatology and urology. Only a few publications exist about examinations of tumors and non-neoplastic lesions of the liver. We report on the application of FCM in biopsies, surgical specimens and autopsy material (33 patients, 39 specimens) of the liver and compare the results to conventional histology. Our preliminary examinations indicated a perfect suitability for tumor diagnosis (ĸ = 1.00) and moderate/good suitability for the assessment of inflammation (ĸ = 0.4-0.6) with regard to their severity and localization. Macro-vesicular steatosis was reliably detected, micro-vesicular steatosis tended to be underestimated. Cholestasis and eosinophilic granules in granulocytes were not represented in the scans. The tissue was preserved as native material and maintained its quality for downstream histological, immunohistological and molecular examinations. In summary, FCM is a material sparing method that provides rapid feedback to the clinician about the presence of tumor, the degree of inflammation and structural changes. This can lead to faster therapeutic decisions in the management of liver tumors, treatment of hepatitis or in liver transplant medicine.

Organ manifestations of COVID-19: what have we learned so far (not only) from autopsies?

The use of autopsies in medicine has been declining. The COVID-19 pandemic has documented and rejuvenated the importance of autopsies as a tool of modern medicine. In this review, we discuss the various autopsy techniques, the applicability of modern analytical methods to understand the pathophysiology of COVID-19, the major pathological organ findings, limitations or current studies, and open questions. This article summarizes published literature and the consented experience of the nationwide network of clinical, neuro-, and forensic pathologists from 27 German autopsy centers with more than 1200 COVID-19 autopsies. The autopsy tissues revealed that SARS-CoV-2 can be found in virtually all human organs and tissues, and the majority of cells. Autopsies have revealed the organ and tissue tropism of SARS-CoV-2, and the morphological features of COVID-19. This is characterized by diffuse alveolar damage, combined with angiocentric disease, which in turn is characterized by endothelial dysfunction, vascular inflammation, (micro-) thrombosis, vasoconstriction, and intussusceptive angiogenesis. These findings explained the increased pulmonary resistance in COVID-19 and supported the recommendations for antithrombotic treatment in COVID-19. In contrast, in extra-respiratory organs, pathological changes are often nonspecific and unclear to which extent these changes are due to direct infection vs. indirect/secondary mechanisms of organ injury, or a combination thereof. Ongoing research using autopsies aims at answering questions on disease mechanisms, e.g., focusing on variants of concern, and future challenges, such as post-COVID conditions. Autopsies are an invaluable tool in medicine and national and international interdisciplinary collaborative autopsy-based research initiatives are essential.

Liver specific overexpression of platelet-derived growth factor-B accelerates liver cancer development in chemically induced liver carcinogenesis.

A genetic basis of hepatocellular carcinoma (HCC) has been well-established and major signaling pathways, such as p53, Wnt-signaling, transforming growth factor-ß (TGF-ß) and Ras pathways, have been identified to be essential to HCC development. Lately, the family of platelet-derived growth factors (PDGFs) has shifted to the center of interest. We have reported on spontaneously developing liver fibrosis in PDGF-B transgenic mice. Since HCC rarely occurs in healthy liver, but dramatically increases at the cirrhosis stage of which liver fibrosis is a preliminary stage, we investigated liver cancer development in chemically induced liver carcinogenesis in these mice. HCC induction was performed by treatment of the mice with diethylnitrosamine and phenobarbital. At an age of 6 months, the tumor development of these animals was analyzed. Not only the development of dysplastic lesions in PDGF-B transgenic mice was significantly increased but also their malignant transformation to HCC. Furthermore, we were able to establish a key role of PDGF-B signaling at diverse stages of liver cancer development. Here, we show that development of liver fibrosis is likely through upregulation of TGF-ß receptors by PDGF-B. Additionally, overexpression of PDGF-B also leads to an increased expression of ß-catenin as well as vascular endothelial growth factor and platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31), all factors with established roles in carcinogenesis. We were able to extend the understanding of key genetic regulators in HCC development by PDGF-B and decode essential downstream signals.

Intraoperative peripheral frozen sections do not significantly affect prognosis after nerve-sparing radical prostatectomy for prostate cancer.

OBJECTIVE: • To determine the value of systematic intraoperative peripheral frozen sections (FS) with or without extended resection during nerve-sparing radical prostatectomy for prediction of biochemical recurrence (BCR) compared with inked surgical margins. PATIENTS AND METHODS: • Between 1999 and 2003, in a prospective study, multiple peripheral FS (median 14; range 5-20) were taken from the urethral stump, circumferentially from the bladder neck, and from the lateral pedicles in 200 consecutive bilateral nerve-sparing radical prostatectomies for clinically localized prostate cancer by a single surgeon. • Patients with stage pT3b or more and/or positive lymph nodes were excluded. • Of the 188 patients, 178 (94.7%) were followed over a median of 82 months (62-124). • BCR, defined as prostate-specific antigen (PSA) ≥ 0.2 ng/mL, was related to status of both, inked specimen margins and FS. RESULTS: • Of all 188 prostatectomy specimens, 49 (26.1%) had positive surgical margins (PSM); these were found posterolaterally in 15 (30.6%), apically in 13 (26.5%), basally in 10 (20.4%) and at multiple sites in 11 (22.4%) specimens. • Intraoperative peripheral FS were positive in 19 (10.7%) patients, including 6.2% at urethral stump, 3.3% at lateral pedicles and 1.1% at bladder neck. • In organ-confined disease, BCR-free survival was 93.3% (111/119) for patients with negative surgical margins (NSM) and 72% (18/25) for patients with PSM (inked specimen), but negative peripheral FS (P < 0.001). • Five- and 10-year BCR-free survival for NSM was 94.9% and 92.8%, for PSM with negative peripheral FS it was 75.3% and 70.6%, and for PSM with positive peripheral FS it was 62.5% and 62.5%, respectively. CONCLUSIONS: • Frozen section biopsies of peripheral resection margins during nerve-sparing radical prostatectomy are not reliable in predicting PSM. • Intraoperative achievement of a locally disease-free status, as monitored by negative circumferential intraoperative FS of peripheral margins, is not associated with a statistically significant BCR-free survival benefit compared with patients with negative surgical margins on the prostatectomy specimen. • Based on these findings, we do not recommend a routine of systematically taking intraoperative FS biopsies during nerve-sparing radical prostatectomy.

Feasibility study for ex vivo fluorescence confocal microscopy (FCM) on diagnostic prostate biopsies.

BACKGROUND: Fluorescence confocal microscopy (FCM) is a novel micro-imaging technique providing optical sections of examined tissue. The method has been well established for the diagnosis of tumours in dermatological specimens. Preliminary results found good feasibility when this technique was used to examine prostate cancer (PCa) specimens. METHODS: We report on the application of FCM in magnet resonance imaging (MRI)-fused prostate biopsies (10 patients, total number of biopsy specimens: n=121) and compare the results to conventional histology. RESULTS: Specific structures of the prostatic tissue were very well represented in the FCM images comparable to conventional histology. Prostate carcinoma was diagnosed with good sensitivity (79/68%) and high specificity (100%) by two pathologists with substantial/almost perfect levels of agreement with the results of conventional histology (kappa 0.79/0.86). Depending on the quality of the scans, malignant lesions of 1.8 mm and more in diameter were reliably diagnosed. Smaller lesions were rated as suspect for malignancy, but could not be consistently differentiated from reactive changes. Optimal image qualities were achieved in focus depths of up to 50 µm, whereas deeper scans led to insufficient representation of cytological features. Pre-treatment with acridine orange (AO) did not alter immunoreactivity of the tissue or its feasibility for fluorescence in situ hybridization (FISH) analyses and adequate amounts of DNA could be extracted for further polymerase chain reaction (PCR)-based examinations. CONCLUSIONS: FCM seems to be a promising tool for the timely diagnosis in cases of PCa in patients requiring therapy. In particular, this technique is a material-sparing method that conserves the biopsies as unfixed material for further analysis such as molecular tumour companion diagnosis.