LMO3 is a suppressor of the basal-like/squamous subtype and reduces disease aggressiveness of pancreatic cancer through glycerol 3-phosphate metabolism.

Pancreatic ductal adenocarcinoma (PDAC) encompasses diverse molecular subtypes, including the classical/progenitor and basal-like/squamous subtypes, each exhibiting distinct characteristics, with the latter known for its aggressiveness. We employed an integrative approach combining transcriptome and metabolome analyses to pinpoint potential genes contributing to the basal-like/squamous subtype differentiation. Applying this approach to our NCI-UMD-German and a validation cohort, we identified LIM Domain Only 3 (LMO3), a transcription co-factor, as a candidate suppressor of the basal-like/squamous subtype. Reduced LMO3 expression was significantly associated with higher pathological grade, advanced disease stage, induction of the basal-like/squamous subtype, and decreased survival among PDAC patients. In vitro experiments demonstrated that LMO3 transgene expression inhibited PDAC cell proliferation and migration/invasion, concurrently downregulating the basal-like/squamous gene signature. Metabolome analysis of patient tumors and PDAC cells revealed a metabolic program linked to elevated LMO3 and the classical/progenitor subtype, characterized by enhanced lipogenesis and suppressed amino acid metabolism. Notably, glycerol 3-phosphate (G3P) levels positively correlated with LMO3 expression and associated with improved patient survival. Furthermore, glycerol-3-phosphate dehydrogenase 1 (GPD1), a crucial enzyme in G3P synthesis, showed upregulation in LMO3-high and classical/progenitor PDAC, suggesting its potential role in mitigating disease aggressiveness. Collectively, our findings suggest that heightened LMO3 expression reduces transcriptome and metabolome characteristics indicative of basal-like/squamous tumors with decreased disease aggressiveness in PDAC patients. The observations describe LMO3 as a candidate for diagnostic and therapeutic targeting in PDAC.

ELAPOR1 induces the classical/progenitor subtype and contributes to reduced disease aggressiveness through metabolic reprogramming in pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is a heterogeneous disease with distinct molecular subtypes described as classical/progenitor and basal-like/squamous PDAC. We hypothesized that integrative transcriptome and metabolome approaches can identify candidate genes whose inactivation contributes to the development of the aggressive basal-like/squamous subtype. Using our integrated approach, we identified endosome-lysosome associated apoptosis and autophagy regulator 1 (ELAPOR1/KIAA1324) as a candidate tumor suppressor in both our NCI-UMD-German cohort and additional validation cohorts. Diminished ELAPOR1 expression was linked to high histological grade, advanced disease stage, the basal-like/squamous subtype, and reduced patient survival in PDAC. In vitro experiments demonstrated that ELAPOR1 transgene expression not only inhibited the migration and invasion of PDAC cells but also induced gene expression characteristics associated with the classical/progenitor subtype. Metabolome analysis of patient tumors and PDAC cells revealed a metabolic program associated with both upregulated ELAPOR1 and the classical/progenitor subtype, encompassing upregulated lipogenesis and downregulated amino acid metabolism. 1-Methylnicotinamide, a known oncometabolite derived from S-adenosylmethionine, was inversely associated with ELAPOR1 expression and promoted migration and invasion of PDAC cells in vitro. Taken together, our data suggest that enhanced ELAPOR1 expression promotes transcriptome and metabolome characteristics that are indicative of the classical/progenitor subtype, whereas its reduction associates with basal-like/squamous tumors with increased disease aggressiveness in PDAC patients. These findings position ELAPOR1 as a promising candidate for diagnostic and therapeutic targeting in PDAC.

[State of the Art Rectal Surgery]. / State of the Art Rektumchirurgie.

The multimodal treatment of rectal cancer has differentiated considerably over the last decade depending on the characteristics of the tumor and the patient's circumstances. Surgery continues to be an important pillar of therapy, the quality of which is of prognostic relevance for affected patients. This review provides an up-to-date overview of the indications for the various surgical procedures, current developments in perioperative management and the timing of surgery.

[Management of Injuries to the Parenchymal Abdominal Organs]. / Management von Verletzungen parenchymatöser Abdominalorgane.

The most common organs affected by abdominal trauma are the spleen and the liver, often in combination. Pancreatic injuries are rare. In the case of blunt abdominal trauma, which is much more common, a clinical and laboratory examination as well as sonography should be performed. In the initial assessment, the circulatory situation must be screened. If there is haemodynamic instability and presentation of free fluid, an emergency laparotomy is indicated. If the situation is stable or stabilised and a pathological sonography is present, it is essential to perform triphasic contrast enhanced computed tomography, which is also mandatory in polytraumatised patients. If a renal injury is suspected, a late venous phase should be attached. In addition to the classification of the injury, attention should be paid to possible vascular injury or active bleeding. In this case, angiography with the possibility of intervention should be performed. Endoscopic treatment is possible for injuries of the pancreatic duct. If the imaging does not reveal any intervention target and a circulation is stable, a conservative approach is possible with continuous monitoring using clinical, laboratory and sonographic controls. Most injuries can be successfully treated by non-operative management (NOM).There are various surgical options for treating the injury, such as local and resecting procedures. There is also the option of "damage control surgery" with acute bleeding control and second look. Complex surgical procedures should be performed at centres. Postoperative complications arise out of elective surgery.In the less common case of penetrating abdominal trauma, the actual extent of the injury cannot be estimated from the visible wound. Here again, the circulatory situation determines the next steps. An emergency laparotomy should be carried out in case of instability. If the condition is stable, further diagnostics should be performed using contrast enhanced computed tomography. If penetration through the peritoneum cannot be clearly excluded, diagnostic laparoscopy should be performed.

Safety and performance of a synthetic sealant patch aimed to prevent postoperative pancreatic fistula after distal pancreatectomy (SHIELDS) - Prospective international multicenter phase II study.

OBJECTIVE: The incidence for clinically relevant postoperative pancreatic fistulas (CR-POPF) in distal pancreatectomy (DP) ranges up to 25%. None of the available sealants significantly reduce CR-POPF. A new biodegradable sealant patch was able to reduce POPF and to achieve bleeding control in a preclinical porcine DP model. The aim of this first-in-human study was to assess the safety and performance of the sealant patch. METHODS: In this multicenter, single-arm study, 40 patients undergoing distal pancreatectomy were prospectively enrolled from 8 centers. Following surgical resection, the transection plane was closed according to the standard of care and manually covered with the sealant patch. As primary endpoint the incidence of CR-POPF up to 30-days postoperatively was evaluated. The secondary endpoints included the assessment of complications and device usability. RESULTS: Among 40 patients after distal pancreatectomy, CR-POPF occurred in 7 (17.5%) up to postoperative day 30. No type C POPF was observed. There was no intraoperative bleeding observed after patch application. CONCLUSION: The results of this international phase II study demonstrate promising results of a new sealant patch regarding the rate of CR-POPF. Randomized studies are now needed to confirm the superiority of the current patch as compared to the best current practice.

Molecular differences of angiogenic versus vessel co-opting colorectal cancer liver metastases at single-cell resolution.

BACKGROUND: Colorectal cancer liver metastases (CRCLM) are associated with a poor prognosis, reflected by a five-year survival rate of 14%. Anti-angiogenic therapy through anti-VEGF antibody administration is one of the limited therapies available. However, only a subgroup of metastases uses sprouting angiogenesis to secure their nutrients and oxygen supply, while others rely on vessel co-option (VCO). The distinct mode of vascularization is reflected by specific histopathological growth patterns (HGPs), which have proven prognostic and predictive significance. Nevertheless, their molecular mechanisms are poorly understood. METHODS: We evaluated CRCLM from 225 patients regarding their HGP and clinical data. Moreover, we performed spatial (21,804 spots) and single-cell (22,419 cells) RNA sequencing analyses to explore molecular differences in detail, further validated in vitro through immunohistochemical analysis and patient-derived organoid cultures. RESULTS: We detected specific metabolic alterations and a signature of WNT signalling activation in metastatic cancer cells related to the VCO phenotype. Importantly, in the corresponding healthy liver of CRCLM displaying sprouting angiogenesis, we identified a predominantly expressed capillary subtype of endothelial cells, which could be further explored as a possible predictor for HGP relying on sprouting angiogenesis. CONCLUSION: These findings may prove to be novel therapeutic targets to the treatment of CRCLM, in special the ones relying on VCO.

Pelvic Intraoperative Neuromonitoring Prevents Dysfunction in Patients With Rectal Cancer: Results From a Multicenter, Randomized, Controlled Clinical Trial of a NEUROmonitoring System (NEUROS).

OBJECTIVE: This NEUROmonitoring System (NEUROS) trial assessed whether pelvic intraoperative neuromonitoring (pIONM) could improve urogenital and ano-(neo-)rectal functional outcomes in patients who underwent total mesorectal excisions (TMEs) for rectal cancer. BACKGROUND: High-level evidence from clinical trials is required to clarify the benefits of pIONM. METHODS: NEUROS was a 2-arm, randomized, controlled, multicenter clinical trial that included 189 patients with rectal cancer who underwent TMEs at 8 centers, from February 2013 to January 2017. TMEs were performed with pIONM (n=90) or without it (control, n=99). The groups were stratified according to neoadjuvant chemoradiotherapy and sex, with blocks of variable length. Data were analyzed according to a modified intention-to-treat protocol. The primary endpoint was a urinary function at 12 months after surgery, assessed with the International Prostate Symptom Score, a patient-reported outcome measure. Deterioration was defined as an increase of at least 5 points from the preoperative score. Secondary endpoints were sexual and anorectal functional outcomes, safety, and TME quality. RESULTS: The intention-to-treat analysis included 171 patients. Marked urinary deterioration occurred in 22/171 (13%) patients, with significantly different incidence between groups (pIONM: n=6/82, 8%; control: n=16/89, 19%; 95% confidence interval, 12.4-94.4; P =0.0382). pIONM was associated with better sexual and ano-(neo)rectal function. At least 1 serious adverse event occurred in 36/88 (41%) in the pIONM group and 53/99 (54%) in the control group, none associated with the study treatment. The groups had similar TME quality, surgery times, intraoperative complication incidence, and postoperative mortality. CONCLUSION: pIONM is safe and has the potential to improve functional outcomes in rectal cancer patients undergoing TME.

MicroRNA-101 Suppresses Tumor Cell Proliferation by Acting as an Endogenous Proteasome Inhibitor via Targeting the Proteasome Assembly Factor POMP.

Proteasome inhibition represents a promising strategy of cancer pharmacotherapy, but resistant tumor cells often emerge. Here we show that the microRNA-101 (miR-101) targets the proteasome maturation protein POMP, leading to impaired proteasome assembly and activity, and resulting in accumulation of p53 and cyclin-dependent kinase inhibitors, cell cycle arrest, and apoptosis. miR-101-resistant POMP restores proper turnover of proteasome substrates and re-enables tumor cell growth. In ERα-positive breast cancers, miR-101 and POMP levels are inversely correlated, and high miR-101 expression or low POMP expression associates with prolonged survival. Mechanistically, miR-101 expression or POMP knockdown attenuated estrogen-driven transcription. Finally, suppressing POMP is sufficient to overcome tumor cell resistance to the proteasome inhibitor bortezomib. Taken together, proteasome activity can not only be manipulated through drugs, but is also subject to endogenous regulation through miR-101, which targets proteasome biogenesis to control overall protein turnover and tumor cell proliferation.

Gene-expression profiles of pretreatment biopsies predict complete response of rectal cancer patients to preoperative chemoradiotherapy.

PURPOSE: Preoperative (neoadjuvant) chemoradiotherapy (CRT) and total mesorectal excision is the standard treatment for rectal cancer patients (UICC stage II/III). Up to one-third of patients treated with CRT achieve a pathological complete response (pCR). These patients could be spared from surgery and its associated morbidity and mortality, and assigned to a "watch and wait" strategy. However, reliably identifying pCR based on clinical or imaging parameters remains challenging. EXPERIMENTAL DESIGN: We generated gene-expression profiles of 175 patients with locally advanced rectal cancer enrolled in the CAO/ARO/AIO-94 and -04 trials. One hundred and sixty-one samples were used for building, training and validating a predictor of pCR using a machine learning algorithm. The performance of the classifier was validated in three independent cohorts, comprising 76 patients from (i) the CAO/ARO/AIO-94 and -04 trials (n = 14), (ii) a publicly available dataset (n = 38) and (iii) in 24 prospectively collected samples from the TransValid A trial. RESULTS: A 21-transcript signature yielded the best classification of pCR in 161 patients (Sensitivity: 0.31; AUC: 0.81), when not allowing misclassification of non-complete-responders (False-positive rate = 0). The classifier remained robust when applied to three independent datasets (n = 76). CONCLUSION: The classifier can identify >1/3 of rectal cancer patients with a pCR while never classifying patients with an incomplete response as having pCR. Importantly, we could validate this finding in three independent datasets, including a prospectively collected cohort. Therefore, this classifier could help select rectal cancer patients for a "watch and wait" strategy. TRANSLATIONAL RELEVANCE: Forgoing surgery with its associated side effects could be an option for rectal cancer patients if the prediction of a pathological complete response (pCR) after preoperative chemoradiotherapy would be possible. Based on gene-expression profiles of 161 patients a classifier was developed and validated in three independent datasets (n = 76), identifying over 1/3 of patients with pCR, while never misclassifying a non-complete-responder. Therefore, the classifier can identify patients suited for "watch and wait".

Endoscopic internal drainage and low negative-pressure endoscopic vacuum therapy for anastomotic leaks after oncologic upper gastrointestinal surgery.

BACKGROUND: Endoscopic internal drainage (EID) with double-pigtail stents or low negative-pressure endoscopic vacuum therapy (EVT) are treatment options for leakage after upper gastrointestinal oncologic surgery. We aimed to compare the effectiveness of these techniques. METHODS: Between 2016 and 2019, patients treated with EID in five centers in France and with EVT in Göttingen, Germany were included and retrospectively analyzed using univariate analysis. Pigtail stents were changed every 4 weeks; EVT was repeated every 3-4 days until leak closure. RESULTS: 35 EID and 27 EVT patients were included, with a median (interquartile range [IQR]) leak size of 0.75 cm (0.5-1.5). Overall treatment success was 100 % (95 % confidence interval [CI] 90 %-100 %) for EID vs. 85.2 % (95 %CI 66.3 %-95.8 %) for EVT (P = 0.03). The median (IQR) number of endoscopic procedures was 2 (2-3) vs. 3 (2-6.5; P = 0.003) and the median (IQR) treatment duration was 42 days (28-60) vs. 17 days (7.5-28; P < 0.001), for EID vs. EVT, respectively. CONCLUSION: EID and EVT provide high closure rates for upper gastrointestinal anastomotic leaks. EVT provides a shorter treatment duration, at the cost of a higher number of procedures.

Rectal Cancer: Open Questions in 2022 Current Standards of Clinical Practice and Ongoing Trials.

BACKGROUND: Rectal cancer remains a complex disease and a relevant global health issue, increasingly affecting also younger patients. This update review summarizes the current standard of care and discusses the individualized treatment approaches taking into consideration individual tumor characteristics and patients preferences. SUMMARY: Remaining "gray zones" of rectal cancer therapy warranting further prospective studies are identified including surgical approaches for rectal cancer, e.g., minimally invasive surgical techniques and lateral lymph node dissection for low rectal cancers. The emerging concept of a watch-and-wait strategy upon clinical complete response after chemoradiotherapy is discussed, also considering the still limited evidence and the clinical challenges arising from individualized patient management. KEY MESSAGES: Finally, currently conducted clinical trials of the German Rectal Cancer Study Group are described, aiming to further individualize multimodal treatment according to risk profiles and strict MRI criteria.

Surgical Therapy in Patients with Colorectal Liver Metastases.

BACKGROUND: Liver metastases (LM) occur in about 50% of patients with colorectal cancer. Besides the multimodal treatment of the primary tumor, the only way to cure patients with colorectal LM (CRLM) is complete resection. Different surgical procedures for this purpose are available depending on location, size, and number of LM. Additional concepts for patients with primary unresectable LM exist, ranging from Chemotherapy to induction of liver hypertrophy and even liver transplantation. This review intends to provide an overview of the surgical approach. SUMMARY: Surgical options in the treatment of CRLM are defined and limited by their intraparenchymal location and their proximity to major vessels and intrahepatic bile ducts. Lesions located in the periphery can be excised in a parenchymal sparing fashion with a small tumor-surrounding resection margin of healthy liver parenchyma. If this is not possible, anatomical resections based on segmental boundaries are performed. In these cases, a sufficient functional volume of liver parenchyma after resection (future liver remnant volume [FLRV]) has to be preserved. This FLRV depends on various factors such as bodyweight and possible preexisting liver damage, such as cirrhosis, fibrosis, or chemotherapy-induced liver impairment. Liver hypertrophy via partial occlusion of the portal venous system is a standard procedure for patients with primary unresectable LM to increase FLRV. Furthermore, discussion of liver transplantation in cases of unresectable LM is gaining importance again. A combination of surgery and adjuvant and/or neoadjuvant chemotherapy may be indicated in individual cases, but general evidence-based recommendations cannot be given without further studies. KEY MESSAGES: Surgical removal of all metastases represents the only option of a potentially curative treatment of UICC stage IV colorectal carcinoma with liver involvement. An interdisciplinary approach consisting of chemotherapeutical downsizing and hypertrophy of the FLRV offers potential curative treatment for patients with initially unresectable metastases. For all others, liver transplantation is seeing a revival showing promising results in overall survival compared to chemotherapy alone.

Treatment options of metastatic and nonmetastatic VIPoma: a review.

PURPOSE: VIPoma belongs to the group of neuroendocrine neoplasms. These tumours are located mostly in the pancreas and produce high levels of vasoactive intestinal peptide (VIP). In most cases, a metastatic state has already been reached at the initial diagnosis, with high levels of VIP leading to a wide spectrum of presenting symptoms. These symptoms include intense diarrhoea and subsequent hypopotassaemia but also cardiac complications, with life-threatening consequences. Treatment options include symptomatic therapy, systemic chemotherapy and targeted therapy, as well as radiation and surgery. Due to the low incidence of VIPoma, there are no prospective studies or evidence-based therapeutic standards to date. METHODS: To evaluate the possible impact of different therapy strategies, we performed literature research using PubMed. RESULTS: All possible treatment modalities for VIPoma have at least one of two therapy goals: antisecretory effects (symptom control) and antitumoural effects (tumour burden reduction). Symptomatic therapy is the most important in the emergency setting to rehydrate, balance electrolytes and stabilise the patient. Symptomatic therapy is also of great importance perioperatively. Somatostatin analogues play a major role in symptom control, although their efficiency is often limited. Chemotherapy may be effective in reaching stable disease for a certain time period, although its impact on symptom control is limited and often delayed. Among targeted therapy options, the usage of sunitinib appears to be the most effective in terms of symptom control and showing antitumoural effects at the same time. Experience with radiation is still limited; however, local ablative procedures seem to be promising options. Peptide receptor radiotherapy (PRRT) with radiolabelled somatostatin analogues (SSAs, 177Lu-DOTATATE) offers a targeted approach, especially in patients with high somatostatin receptor density. Surgery is the first-line therapy for nonmetastatic VIPoma. Additionally, if the resection of all visible tumour lesions is possible, the surgical approach seems preferable to other strategies in highly symptomatic patients. The role of surgery in very advanced stages where only tumour debulking is possible remains debatable. However, a high rate of immediate symptom control can be achieved by tumour debulking followed by somatostatin therapy, although the impact on survival remains unclear. CONCLUSION: Surgery is the only curative option for nonmetastatic VIPoma. Additionally, surgery should be a first-line therapy option for highly symptomatic patients, especially if the resection of all tumour lesions (primary tumour and metastasis) is achievable. In frail patients, other modalities can be used.

Needle tract seeding and abdominal recurrence following pre-treatment biopsy of gastrointestinal stromal tumors (GIST): results of a systematic review.

BACKGROUND: Gastrointestinal stromal tumors (GIST) are rare abdominal tumors. Pretreatment biopsies may be used to diagnose a GIST and enable tailored treatment. Some experts are skeptical about biopsies because they fear tumor cell seeding. The objective of this study was to determine if pretreatment biopsy is associated with increased tumor recurrence. METHODS: We performed a systematic literature search and included studies assessing the oncological outcome of GIST patients who underwent a pre-treatment core needle biopsy or fine needle aspiration. We assessed methodological quality with the Newcastle-Ottawa-Scale for non-randomized studies. This review was registered in the PROSPERO database (CRD42021170290). RESULTS: Three non-randomized studies and eight case reports comprising 350 patients were eligible for inclusion. No prospective study designed to answer the review question was found. One case of needle tract seeding after percutaneous core needle biopsy of GIST was reported. None of the studies reported an increased rate of abdominal recurrence in patients with pretreatment biopsy. CONCLUSIONS: The existing evidence does not indicate a relevant risk of needle tract seeding or abdominal recurrence after pre-treatment biopsy of GIST. Biopsy can safely be done to differentiate GIST from other tumors and to select the most appropriate treatment.

Outcomes and risks in palliative pancreatic surgery: an analysis of the German StuDoQ|Pancreas registry.

BACKGROUND: Non-resectability is common in patients with pancreatic ductal adenocarcinoma (PDAC) due to local invasion or distant metastases. Then, biliary or gastroenteric bypasses or both are often established despite associated morbidity and mortality. The current study explores outcomes after palliative bypass surgery in patients with non-resectable PDAC. METHODS: From the prospectively maintained German StuDoQ|Pancreas registry, all patients with histopathologically confirmed PDAC who underwent non-resective pancreatic surgery between 2013 and 2018 were retrospectively identified, and the influence of the surgical procedure on morbidity and mortality was analyzed. RESULTS: Of 389 included patients, 127 (32.6%) underwent explorative surgery only, and a biliary, gastroenteric or double bypass was established in 92 (23.7%), 65 (16.7%) and 105 (27.0%). After exploration only, patients had a significantly shorter stay in the intensive care unit (mean 0.5 days [SD 1.7] vs. 1.9 [3.6], 2.0 [2.8] or 2.1 [2.8]; P < 0.0001) and in the hospital (median 7 days [IQR 4-11] vs. 12 [10-18], 12 [8-19] or 12 [9-17]; P < 0.0001), and complications occurred less frequently (22/127 [17.3%] vs. 37/92 [40.2%], 29/65 [44.6%] or 48/105 [45.7%]; P < 0.0001). In multivariable logistic regression, biliary stents were associated with less major (Clavien-Dindo grade ≥ IIIa) complications (OR 0.49 [95% CI 0.25-0.96], P = 0.037), whereas-compared to exploration only-biliary, gastroenteric, and double bypass were associated with more major complications (OR 3.58 [1.48-8.64], P = 0.005; 3.50 [1.39-8.81], P = 0.008; 4.96 [2.15-11.43], P < 0.001). CONCLUSIONS: In patients with non-resectable PDAC, biliary, gastroenteric or double bypass surgery is associated with relevant morbidity and mortality. Although surgical palliation is indicated if interventional alternatives are inapplicable, or life expectancy is high, less invasive options should be considered.

[Personalised Surgical Therapy for Neuroendocrine Neoplasia of the Pancreas]. / Personalisierte Resektionsverfahren bei neuroendokrinen Neoplasien des Pankreas.

Neuroendocrine neoplasia of the pancreas (pNEN) has an increasing incidence and is therefore becoming increasingly clinically relevant. In addition to hormonally inactive pNEN, there are hormone-producing tumours and both inactive and active pNEN can be either sporadic or hereditary. Treatment is not only based on tumour-associated factors, but also on the individual patient's own circumstances. Treatment must be based on individual, tailor-made concepts that consider the respective factors and circumstances.

Intensified Histopathological Work-Up after Pancreatic Head Resection Reveals Relevant Prognostic Markers.

INTRODUCTION: Local recurrence remains a major problem after pancreatic head resection. Intensified histopathological work-up of surgical specimens after pancreatic head resection has revealed an increased number of incomplete resections (R1) depending on tumor infiltration front at the resection margins (RMs). It remains unclear to which extent the increased R1 resection rate has a clinical relevance for the patients' prognosis. MATERIALS AND METHODS: Pancreatic head resections between 2006 and 2012 were histologically intensively worked-up by a previously described protocol. The distance between the tumor infiltration front and the resection planes or organ surfaces was documented. The impact of the size of the tumor and an additional portal vein resection was analyzed. The effect of a R1 resection status on development and type of recurrence was evaluated. RESULTS: A total of 203 pancreatic head resections were evaluated. Different definitions of R1 resection were applied. These led to significantly different prognosis for patients. A greater distance between the tumor infiltration front and the resection plane or organ surface was associated with a better outcome for the patients. For the ventral surface, the mesopancreas and the pancreatic body these differences were statistically significant comparing the different R1 definitions. For the dorsal surface, a significant difference in prognosis was found if the tumor was >2 mm away from the resection surface. A tumor size of 3 cm was identified to play a relevant role for the prognosis. Patients who had a portal vein resection without a histologically proven infiltration showed a statistically significant higher overall survival. Patients with R1 resection were at highest risk for developing local recurrence as well as distant metastasis. CONCLUSION: Intensified histopathological work-up with an increased number of R1 resections has a clinical relevance for patients' prognosis. Tumors with a smaller size or with a greater distance to the organ surface or RM have a better outcome.

Enhancer of Zeste Homolog 2 in Colorectal Cancer Development and Progression.

BACKGROUND: Colorectal cancer (CRC) is the leading gastrointestinal malignancy. The development from premalignant intraepithelial lesions leading to invasive cancer is paradigmatic for the stepwise carcinogenesis of epithelial cancers, but the knowledge of the underlying mechanism of carcinogenesis and progression of CRC is still incomplete. The understanding of epigenetic mechanisms of carcinogenesis has led to new therapeutic approaches during the last years. Enhancer of zeste homolog 2 (EZH2) is one central epigenetic silencer of the polycomb repressor complex 2 (PRC2) that is already in clinical use as a novel drug target and is associated with poorer prognosis in several cancer entities. PATIENTS AND METHODS: The protein expression of EZH2 and other members of the PRC2 as well as resulting posttranslational modifications were investigated by immunohistochemistry in 187 patients with CRC and in 94 patients with premalignant colorectal lesions and correlated with their clinical outcome. Furthermore, the corresponding mRNA expression levels were analyzed in 217 patients with rectal cancer that were enrolled in a prospective clinical trial. RESULTS: We found a weak expression of EZH2 in normal colon mucosa that increased in low grade, peaked in high grade intraepithelial neoplasia, and decreased again in invasive CRC. The posttranslational modification caused by EZH2 as a measure of EZH2 activity showed the same behavior. Strong protein and mRNA expression of EZH2 were significantly correlated with favorable prognosis in both investigated cohorts. CONCLUSION: The expression and activity of EZH2 are associated with colorectal carcinogenesis and most expressed in intraepithelial high-grade lesions. Strong expression of EZH2 is associated with a significantly favorable prognosis in patients suffering from CRC.

Impact of Endoscopic Vacuum Therapy with Low Negative Pressure for Esophageal Perforations and Postoperative Anastomotic Esophageal Leaks.

INTRODUCTION: Management of esophageal anastomotic leaks (AL) and esophageal perforations (EP) remains difficult and often requires an interdisciplinary treatment modality. For primary endoscopic management, self-expanding metallic stent (SEMS) placement is often considered first-line therapy. Recently, endoscopic vacuum therapy (EVT) has emerged as an alternative or adjunct for management of these conditions. So far, data for EVT in the upper gastrointestinal-tract is restricted to single centre, non-randomized trials. No studies on optimal negative pressure application during EVT exist. The aim of our study is to describe our centre's experience with low negative pressure (LNP) EVT for these indications over the past 5-years. PATIENTS AND METHODS: Between January 2014 and December 2018, 30 patients were endoscopically treated for AL (n = 23) or EP (n = 7). All patients were primarily treated with EVT and LNP between -20 and -50 mm Hg. Additional endoscopic treatment was added when EVT failed. Procedural and peri-procedural data, as well as clinical outcomes including morbidity and mortality, were analysed. RESULTS: Clinical successful endoscopic treatment of EP and AL was achieved in 83.3% (n = 25/30), with 73.3% success using EVT alone (n = 22/30). Mean treatment duration until leak closure was 16.1 days (range 2-58 days). Additional treatment modalities for complete leak resolution was necessary in 10% (n = 3/30), including SEMS placement and fibrin glue injection. Mean hospital stay for patients with EP was shorter with 33.7 days compared to AL with 54.4 days (p = 0.08). Estimated preoperative 10-year overall survival (Charlson comorbidity score) was 39.4% in patients with AL and 59.9% in patients with EP (p = 0.26). A mean of 5.1 EVT changes (range 1-12) was needed in EP and 3.6 changes (range 1-13) in AL to achieve complete closure, switch to other treatment modality, or reach endoscopic failure (p = 0.38). CONCLUSION: LNP EVT enables effective minimally - invasive endoluminal leak closure from anastomotic esophageal leaks and EP in high-morbid patients. In this study, EVT was combined with other endoscopic treatment options such as SEMS placement or fibrin glue injection in order to achieve leak or perforation closure in the vast majority of patients (83.3%). Low aspiration pressures led to slower but still sufficient clinical results.

[Prerequisites of magnetic resonance imaging for treatment planning in locally advanced rectal cancer - Interdisciplinary recommendations]. / Stellenwert und qualitative Voraussetzungen der Magnetresonanztomografie für die Therapieplanung beim lokal fortgeschrittenen Rektumkarzinom ­ Interdisziplinäre Empfehlungen.

For the purpose of indication and patient stratification of perioperative treatment of locally advanced rectal cancer, magnetic resonance imaging (MRI) has become indispensable. In this report, we describe the importance of MRI diagnostics and the qualitative conditions.