Bio-absorbable sealants for reinforcing the pancreatic stump after distal pancreatectomy are critical

Background

Bio‐absorbable sealants are widely used to reduce the rate and severity of postoperative pancreatic fistulas after distal pancreatectomy. However, numerous clinical trials have failed to demonstrate their clinical benefit. We therefore investigated stability and bio‐compatibility of absorbable sealants in vitro and in vivo.

Methods

In vitro, polymerized compounds were incubated in pancreatic juice before their stability was tested. In vivo, two compounds were used to seal the pancreatic stump after distal pancreatectomy in nine pigs. Burst pressure of the pancreatic stump, surgical outcome, histology of the pancreatic stump, systemic inflammation, and drain fluid was examined.

Results

Products based on fibrin or collagen were unstable in the presence of active pancreatic enzymes and completely dissolved within 2 h. Sealants using chemical cross‐linking of proteins showed improved stability for 7 days. In vivo, application of polyethylenglycol‐based sealant leads to complete closure of the pancreatic duct after 5 days, while a glutaraldehyde‐based sealant prevented physiological closure of the pancreatic main duct.

Conclusions

Many compounds used clinically to reinforce the pancreatic stump after distal pancreatectomy are inadequate due to instability in the presence of pancreatic enzymes. While selected bio‐absorbable sealants inhibited the natural healing of the pancreatic stump, polyethylenglycol‐based sealants should be tested in further clinical trials.

Advanced Mucinous Colorectal Cancer: Epidemiology, Prognosis and Efficacy of Chemotherapeutic Treatment

BACKGROUND

The clinicopathological significance of the mucinous subtype of colorectal cancer (CRC) remains controversial. As of today, none of the current guidelines differentiate treatment with respect to mucinous or nonmucinous cancer. Due to the lack of substantiated data, best treatment remains unclear and the mucinous subtype of CRC is usually treated along the lines of recommendations for adenocarcinoma of the colon.

METHODS

We investigated an East-Bavarian cohort of 8,758 patients with CRC. These included 613 (7.0%) patients with a mucinous subtype, who were analyzed for assessing their characteristics in clinical course and for evaluating the efficacy of common chemotherapy protocols.

RESULTS AND CONCLUSION

Mucinous CRC was predominantly located in the right hemicolon; it was diagnosed at more advanced stages and occurred with preponderance in women. A higher rate of G3/4 grading was observed at diagnosis (all p < 0.001). An association of mucinous CRC with younger age at initial diagnosis, previously reported by other groups, could not be confirmed. Patients with mucinous stage IV colon cancer demonstrated poorer survival (p = 0.006). In contrast, no differences in survival were observed for specific stages I-III colon cancer. Stage-dependent analysis of rectal cancer stages I-IV also showed no differences in survival. However, univariable overall analysis resulted in significant poorer survival of mucinous compared to nonmucinous rectal cancer (p = 0.029). Also, combined analysis of all patients with mucinous CRC revealed poorer overall survival (OS) of these patients compared to nonmucinous CRC patients (median 48.4 vs. 60.2 months, p = 0.049) but not in multivariable analysis (p = 0.089). Chemotherapeutic treatment showed comparable efficacy regarding OS for mucinous and nonmucinous cancers in both an adjuvant and palliative setting for colon cancer patients (p values comparing mucinous and nonmucinous cancers < 0.001-0.005).

Surgical outcomes of renal transplant recipients after abdominal surgery not connected with transplantation. A retrospective case-control study

BACKGROUND

Due to the increasing number of patients after kidney transplantation, elective and emergency surgery of transplanted patients is becoming a relevant challenge in clinical routine. The current data on complication rate of patients after kidney transplantation, which must undergo another elective or emergency abdominal surgery, is inhomogeneous. Therefore, the aim of our study was to evaluate the outcome of renal transplant patients undergoing abdominal and abdominal wall surgery.

MATERIAL AND METHODS

We performed an observational study of patients after kidney transplantation undergoing graft-unrelated abdominal surgery between 2005 and 2015. We randomly created a non-transplanted control for a case-matched controlled analysis. Primary endpoint was the comparison of complication rate. Secondary, a risk analysis of all patients was performed and differences in mortality, length of hospital stay and reoperation rates were calculated.

RESULTS

Overall 101 kidney transplanted patients were eligible for inclusion. 20 (19.8%) died after graft-unrelated surgery and 60 (59.4%) suffered from postoperative complications. Case-matched analysis could be performed for 84 out of these 101 patients. We found no significant difference in morbidity rate (58.3% vs. 45.2%, p = 0.090). Transplanted patients had, however, a significantly higher mortality (19% vs. 2.4%, p = 0.001), a longer hospital stay (28.2 vs. 16.9 days, p = 0.020) and a higher rate of re-operations (38.1% vs. 20.2%, p = 0.017). .

CONCLUSIONS

Patients after renal transplantation undergoing graft-unrelated abdominal surgery have a significantly increased mortality risk, are more frequently re-operated and have to stay significantly longer in hospital than non-transplanted patients.

Clinical Management of Appendicitis

Background

Ever since the first appendectomy has been performed, surgery has been the standard of care for acute appendicitis, with antibiotic therapy being reserved for special situations. Recent studies have shown the feasibility of antibiotic therapy for uncomplicated appendicitis.

Methods

This clinical therapeutic review is based both on author expertise and a selective literature survey in PubMed based on the term 'appendicitis', combined with the terms 'acute', 'complicated', 'conservative', 'non-operative', 'therapy', 'surgery', and 'strategy'. According to these search results as well as to the treatment guidelines from the American College of Surgeons, Society for Surgery of the Alimentary Tract, Society of American Gastrointestinal and Endoscopic Surgeons, European Association of Endoscopic Surgery, and World Society of Emergency Surgery, we present an interdisciplinary treatment concept.

Results

Approximately 90% of patients treated with antibiotics are able to avoid surgery during the initial admission. The other 10% that fail to respond to antibiotics require a rescue appendectomy. Recurrence rates of non-operated patients within 1 year are as high as 20-30%.

Conclusion

In uncomplicated appendicitis without risk factors for failure of non-operative management, a shared decision based on the patient's preferences should be made. In cases with risk factors, appendectomy is still the treatment recommended. If the diagnosis is uncertain or clinical symptoms are rather mild, antibiotic therapy should be started. In complicated appendicitis, management depends on the clinical state, with either immediate surgery or primarily antibiotic therapy and combined with drainage of abscess, being followed by interval appendectomy in some cases.

Inhibition of mTORC2/RICTOR Impairs Melanoma Hepatic Metastasis

Mammalian target of rapamycin complex 2 (mTORC2) with its pivotal component rapamycin-insensitive companion of mTOR (RICTOR) is the major regulator of AKT phosphorylation and is increasingly implicated in tumor growth and progression. In cutaneous melanoma, an extremely aggressive and highly metastatic disease, RICTOR overexpression is involved in tumor development and invasiveness. Therefore, we investigated the impact of RICTOR inhibition in melanoma cells in vitro and in vivo with special emphasis on hepatic metastasis. Moreover, our study focused on the interaction of tumor cells and hepatic stellate cells (HSC) which play a crucial role in the hepatic microenvironment. In silico analysis revealed increased RICTOR expression in melanoma cells and tissues and indicated higher expression in advanced melanoma stages and metastases. In vitro, transient RICTOR knock-down via siRNA caused a significant reduction of tumor cell motility. Using a syngeneic murine splenic injection model, a significant decrease in liver metastasis burden was detected in vivo. Moreover, stimulation of melanoma cells with conditioned medium (CM) from activated HSC or hepatocyte growth factor (HGF) led to a significant induction of AKT phosphorylation and tumor cell motility. Blocking of RICTOR expression in cancer cells diminished constitutive and HGF-induced AKT phosphorylation as well as cell motility. Interestingly, RICTOR blockade also led to an abrogation of CM-induced effects on AKT phosphorylation and motility in melanoma cells. In conclusion, these results provide first evidence for a critical role of mTORC2/RICTOR in melanoma liver metastasis via cancer cell/HSC interactions.

Outcome after hepatic resection for isolated non-colorectal, non-neuroendocrine liver metastases in 100 patients - the role of the embryologic origin of the primary tumor

Background

The indication for hepatic resection (HR) in patients suffering from liver metastases (LM) other than colorectal and neuroendocrine tumors is one focus of current multidisciplinary, oncologic considerations. This study retrospectively analyzes outcome after HR for non-colorectal, non-neuroendocrine (NCNNE) LM in the absence of distant or extrahepatic metastases.

Methods

We included 100 consecutive patients undergoing HR for isolated NCNNE LM from a prospective database in our institution, including postoperative follow-up. Primary tumors were of mesodermal origin in 44%, of ectodermal origin in 29% and of entodermal origin in 27%. Survival analysis was performed by univariate and multivariable methods. Mean follow-up after hepatic surgery was 3.6 years (0.25–16).

Results

Median age at the time of HR was 59.5 years. Kaplan-Meier-estimated survival after liver resection was 56.8%, 34.3% and 24.5% after 5, 10 and 15 years, respectively. Univariate analysis after HR revealed residual disease (hepatic or primary; p = 0.02), female gender (p = 0.013), entodermal origin (p = 0.009) and early onset of metastatic disease (≤24 months, p = 0.002), as negative prognostic factors. Multivariable survival analysis confirmed residual disease, female gender, entodermal embryologic origin and early onset of metastatic disease (≤24 months) as independent negative prognostic factors.

Conclusion

Overall outcome after HR of NCNNE LM results in acceptable long-term outcome. Although individual decision-making today mostly relies on clinical experience for this type of disease, risk factors derived from the embryologic origin of the tumor might help in patient selection.

Does the site of primary colorectal cancer influence the outcome after resection of isolated liver metastases?

INTRODUCTION

In unresectable patients with metastatic colorectal cancer (CRC), the site of the primary is a strong prognostic factor warranting major adjustments in palliative medical treatment. Initial results suggested that the site of CRC influences prognosis after curative resection of colorectal liver metastases (CLM). In this study, we evaluated outcome after resection of isolated CLM with regard to the location of the primary.

METHODS

221 patients with macroscopically complete resection of CLM and no known extrahepatic disease were identified. 63 patients had right-sided and 158 had left-sided CRC. Tumors of the transverse colon and rectum were excluded. Survival was evaluated using the Kaplan-Meier method.

RESULTS

Characteristics of CLM, primary tumor stage and chemotherapeutic regimens were not significantly different between the two groups. Kaplan-Meier five-year survival was comparable (41%) in patients with right- or left-sided CRC (p = 0.64). Microscopic resection margin, number of liver metastases, age and nodal status but not the site of the primary tumor significantly influenced survival.

CONCLUSION

The site of the colorectal primary in this well-defined group of patients after resection of isolated CLM did not prove to be of significant prognostic value. Whether the primary tumor in CLM is located on the left side or the right should not preclude patients from surgery.

[The German snowball effect : An increasing aftercare problem in bariatric treatment]

BACKGROUND

The surgical treatment of obesity in Germany is a rapidly developing field which is strictly controlled by national guidelines.

OBJECTIVE

Depiction of the burden on obesity centers by the exponential increase in numbers of patients following bariatric treatment.

METHODS

In a retrospective study the numbers of outpatients at this university obesity center (founded 2007) were descriptively analyzed. Outpatient visits were documented annually and divided into two groups: primary visit and follow-up visit. The frequency of bariatric operations as well as their acceptance/cost coverage by health insurances were evaluated.

RESULTS

Overall 318 patients were seen in 2007: 156 primary and 162 follow-up visits. The health insurance rejection rate for cost coverage was 16.8%. There were 1691 outpatient visits in 2016 (2016 vs. 2007: +532%), of which 487 (+312%) were primary and 1204 (+743%) follow-up visits. The health insurance rejection rate dropped to 1.8%, while the frequency of operations increased nearly tenfold.

CONCLUSION

With the increasing acceptance of bariatric surgery, a relatively low number of specialized centers have to deal with an exponentially rising follow-up frequency. In consideration of the extent of the obesity epidemic an adequate follow-up constitutes a socioeconomic problem, which can only be solved in an interdisciplinary setting under structural integration.

Repair of a Grynfeltt-Lesshaft hernia with the PROCEED™ VENTRAL PATCH: a case report

Background

Primary hernias in the triangle of Grynfeltt are very rare and therefore pose a difficulty in diagnosis and treatment. Due to the lack of systematic studies, the surgical approach must be chosen individually for each patient. Here, we describe an easy and safe surgical approach.

Case presentation

We report the case of a 53-year-old male patient with a history of mental disability and pronounced scoliosis, who presented with a Grynfeltt-Lesshaft hernia with protrusion of the ascending colon and the right ureter.

The hernia was repaired via a dorsal, extraperitoneal approach. The hernia gap with a diameter of approximately 1 cm was closed with insertion of a 6.4 × 6.4 cm PROCEED™ VENTRAL PATCH (Ethicon, Norderstedt, Germany). The operating time was 33 min and the patient was discharged the next day and showed no signs of recurrence at 1-year follow up.

Conclusion

The technique described here is favorable because it requires very little dissection of the surrounding tissue and no trans-/intraabdominal dissection. The technique was chosen in this particular case to guarantee a fast postoperative recovery and prompt hospital discharge.

[Hepatocellular Carcinoma: New multimodal therapy concepts]

STATUS QUO

Hepatocellular carcinoma guidelines are currently under revision. A new edition is expected in 2018. Patients with chronic liver diseases or cirrhosis require HCC screening by ultrasound every 6 months. Surgical resection or liver transplantation are curative treatment options for early stage HCC.

LOCOREGIONAL THERAPY APPROACHES

A more and more common and well tolerated locoregional therapy approach based on study data is selective internal radio therapy (SIRT), although studies did not show an improvement in outcome comparing SIRT to transarterial chemotherapy (TACE) in BCLC B or sorafenib in BCLC C.

SYSTEMIC THERAPY APPROACHES

Looking at targeted therapies regorafenib is approved for patients under treatment with sorafenib and disease progression as a second line therapy. Positive phase III-study data have been published for lenvatinib as first-line and cabozantinib as second-line therapy. Nivolumab was approved by the FDA as second-line therapy after positive phase I/II-study outcomes. A study on nivolumab versus sorafenib as first-line therapy will be published in 2018.

Oncological outcome of laparoscopically assisted pancreatoduodenectomy for ductal adenocarcinoma in a retrospective cohort study

INTRODUCTION

Laparoscopic resections of the pancreatic head are increasingly performed. Several studies show that they are comparable to open operations in terms of postoperative morbidity. However, since a substantial proportion of pancreatic head resections are necessary for pancreatic adenocarcinoma the oncologic safety and outcome of minimally invasive operations is of interest. In this study we evaluated oncologic outcome and survival after laparoscopically assisted pancreatic head resection for ductal adenocarcinoma.

METHODS

Perioperative and oncological outcome of sixty-two laparoscopically assisted pancreatic head resections for pancreatic ductal adenocarcinoma performed between 2010 and 2016 was compared to outcome of 278 open resections between 2001 and 2016 in a retrospective study. Data was continuously collected in a prospectively maintained database.

RESULTS

Operation time was significantly longer in the laparoscopic group (477 vs. 428 min. p < 0.001). Tumor size, lymph node yield and lymph node state and need of portal vein resection were comparable. There was a higher rate of free resection margins in the laparoscopic group (87% vs. 71%, p < 0.01). There was no difference in postoperative mortality and morbidity. Patients with laparoscopic resection stayed in hospital significantly shorter (median 14 vs. 16 days, p < 0.003). Postoperative survival after 5 years was not different in both groups.

CONCLUSION

Laparoscopically assisted resection of adenocarcinoma of the pancreatic head is equal to open resection concerning oncologic outcome and actuarial survival. However, minimally invasive resection shortened the hospital stay. However, further evaluations with a longer follow up time are needed.

Microbial Spectrum of Intra-Abdominal Abscesses in Perforating Crohn's Disease: Results from a Prospective German Registry

BACKGROUND

Intra-abdominal abscesses [IAAs] are common life-threatening complications in patients with Crohn's disease [CD]. In addition to interventional drainage and surgical therapy, empirical antibiotic therapy represents a cornerstone of treatment, but contemporary data on microbial spectra and antimicrobial resistance are scarce.

METHODS

We recruited 105 patients with CD and IAAs from nine German centres for a prospective registry in order to characterize the microbiological spectrum, resistance profiles, antibiotic therapy and outcome.

RESULTS

In 92 of 105 patients, microbial investigations of abscess material revealed pathogenic microorganisms. A total of 174 pathogens were isolated, with a median of 2 pathogens per culture [range: 1-6]. Most frequently isolated pathogens were E. coli [45 patients], Streptococcus spp. [28 patients], Enterococci [27 patients], Candida [13 patients] and anaerobes [12 patients]. Resistance to third-generation cephalosporins, penicillins with beta-lactamase inhibitors and quinolones were observed in 51, 36 and 35 patients, respectively. Seven patients had multiple-drug-resistant bacteria. Thirty patients received inadequate empirical treatment, and this was more frequent in patients receiving steroids or immunosuppression [37%] than in patients without immunosuppression [10%: p = 0.001] and was associated with a longer hospital stay [21 days vs 13 days, p = 0.003].

CONCLUSION

Based on antimicrobial resistance profiles, we herein report a high rate of inadequate empirical first-line therapy for IAAs in CD, especially in patients receiving immunosuppression, and this is associated with prolonged hospitalization.

[Intrahepatic cholangiocarcinoma : Results after 84 resections]

BACKGROUND

The incidence of intrahepatic cholangiocarcinoma (ICC) is increasing worldwide. Surgical resection is the only curative treatment option.

AIM OF THE STUDY

This study analyzed the prognostic factors after resection of ICC.

MATERIAL AND METHODS

A total of 84 patients were surgically treated under potentially curative intent. Perihilar and distal cholangiocarcinomas were excluded. The 5‑year survival was analyzed with respect to tumor stage (TNM), number of lesions, complete surgical resection (R0), peritoneal carcinosis and postoperative complications.

RESULTS

The 5‑year survival was 27% and 77% of patients underwent R0 resections. In the univariate analysis a T stage >2, an N+ situation or an R+ resection as well as peritoneal and multilocular intrahepatic spread were associated with a poorer prognosis. Postoperative complications also negatively influenced survival. On multivariate analysis the absence of peritoneal spread, node-negative tumor stages, singular hepatic lesions and a low T stage as well as the absence of complications were associated with improved survival.

DISCUSSION

The prognosis of ICC is poor even after successful surgical resection. Well-known tumor characteristics such as TNM are relevant prognostic factors. Surgical resection is accompanied by postoperative complications (most frequently biliary), which negatively influence survival. Adjuvant strategies are urgently needed to improve long-term survival even after complete surgical resection.

Hemoadsorption in a Case of Severe Septic Shock and Necrotizing Fasciitis Caused by Nontraumatic Renal Rupture due to Pyelonephritis with Obstructive Uropathy

BACKGROUND

Nontraumatic renal rupture due to pyelonephritis with obstructive uropathy is an uncommon but life-threatening situation.

CASE PRESENTATION

A 25-year-old female presented to the emergency department with acute worsening of abdominal pain that began four weeks earlier. She was found to have peritonitis, leukocytosis, severe lactic acidosis, and a pronounced anemia and imaging was consistent with nontraumatic renal rupture with retroperitoneal abscess, perforation of the colon, and severe necrotizing fasciitis of the right lower limb. She underwent a right nephrectomy, a right hemicolectomy, surgical debridement of the retroperitoneum, and an upper thigh amputation. Due to severe septic shock and rhabdomyolysis with acute renal failure we performed a combined treatment of hemoadsorption using a Cytosorb hemoadsorber and continuous venovenous hemodialysis (CVVHD). Subsequently the patient recovered and was discharged home with no signs of infections and with normal renal function.

CONCLUSION

We present a case of pyelonephritis with nontraumatic renal rupture leading to necrotizing fasciitis with osteomyelitis of the lower limb. The early treatment of the patient with a Cytosorb hemoadsorber led to a rapid hemodynamic and metabolic stabilization and preservation of the renal function, suggesting that hemoadsorption might be a rescue therapy in patients with severe septic shock and traumatic rhabdomyolysis.

Chemotherapy for metastatic colon cancer: No effect on survival when the dose is reduced due to side effects

BACKGROUND

5-Fluorouracil (5FU), Folinic acid (FA), and Oxaliplatin (FOLFOX) or 5FU, FA, and Irinotecan (FOLFIRI) are standard regimens for palliative chemotherapy of metastatic colon cancer. Since data showing the influence of dose reduction in palliative treatment are rare, the objective of this single center, retrospective study was to further characterize the influence of dose reduction on efficacy of these therapeutic regimens.

METHODS

One hundred nine patients, diagnosed with stage IV colon cancer between 2004 and 2012 and receiving palliative first-line chemotherapy with either FOLFOX or FOLFIRI regimens in our outpatient clinic were analyzed for treatment efficacy. Patients who received dose reductions due to side effects usually received doses of 80% or lower of per protocol dose. Survival data were obtained from the Regensburg Tumor Registry. Survival analysis was performed using Kaplan-Meier statistical analysis and multivariable analysis.

RESULTS

A dose reduction due to side effects was necessary in 46 (42%) patients. Dose reduction was independent of age. Major reasons for dose reduction were neutropenia (30%) followed by polyneuropathy (16%) and diarrhea (14%). Dosage was more often reduced in patients receiving FOLFOX based therapy. Comparison of patients with dose reduction versus patients with full dosage showed no significant difference on overall survival (p = 0.430). Subgroup analysis revealed dose reduction in patients with N2 stage disease was associated with improved survival. Patients who underwent dose reduction received more cycles of chemotherapy (13.7 vs. 10.8 cycles) and cumulative dosage was similar in both groups.

CONCLUSION

Contrary to our expectations, the need to reduce chemotherapy dosage due to side effects does not indicate a worse prognosis in our retrospective analysis. We believe this can in part be explained by better adaption to interindividual pharmacokinetics and longer time of treatment.

Postoperative changes of the microbiome: are surgical complications related to the gut flora? A systematic review

BACKGROUND

The purpose of this review was to identify the relationship between the gut microbiome and the development of postoperative complications like anastomotic leakage or a wound infection. Recent reviews focusing on underlying molecular biology suggested that postoperative complications might be influenced by the patients' gut flora. Therefore, a review focusing on the available clinical data is needed.

METHODS

In January 2017 a systematic search was carried out in Medline and WebOfScience to identify all clinical studies, which investigated postoperative complications after gastrointestinal surgery in relation to the microbiome of the gut.

RESULTS

Of 337 results 10 studies were included into this analysis after checking for eligibility. In total, the studies comprised 677 patients. All studies reported a postoperative change of the gut flora. In five studies the amount of bacteria decreased to different degrees after surgery, but only one study found a significant reduction. Surgical procedures tended to result in an increase of potentially pathogenic bacteria and a decrease of Lactobacilli and Bifidobacteria. The rate of infectious complications was lower in patients treated with probiotics/symbiotics compared to control groups without a clear relation to the systemic inflammatory response. The treatment with synbiotics/probiotics in addition resulted in faster recovery of bowel movement and a lower rate of postoperative diarrhea and abdominal cramping.

CONCLUSIONS

There might be a relationship between the gut flora and the development of postoperative complications. Due to methodological shortcomings of the included studies and uncontrolled bias/confounding factors there remains a high level of uncertainty.

Bile duct regeneration and immune response by passenger lymphocytes signals biliary recovery versus complications after liver transplantation

This study aimed to elucidate the impact of epithelial regenerative responses and immune cell infiltration on biliary complications after liver transplantation. Bile duct (BD) damage after cold storage was quantified by a BD damage score and correlated with patient outcome in 41 patients. Bacterial infiltration was determined by fluorescence in situ hybridization (FISH). BD samples were analyzed by immunohistochemistry for E-cadherin, cytokeratin, CD56, CD14, CD4, CD8, and double-immunofluorescence for cytokine production and by messenger RNA (mRNA) microarray. Increased mRNA levels of adherens junctions (P < 0.01) were detected in damaged BDs from patients without complications compared with damaged BDs from patients with biliary complications. Immunohistochemistry showed increased expression of E-cadherin and cytokeratin in BDs without biliary complications (P = 0.03; P = 0.047). FISH analysis demonstrated translocation of bacteria in BDs. However, mRNA analysis suggested an enhanced immune response in BDs without biliary complications (P < 0.01). Regarding immune cell infiltration, CD4⁺ and CD8⁺ cells were significantly increased in patients without complications compared with those with complications (P = 0.02; P = 0.01). In conclusion, following BD damage during cold storage, we hypothesize that the functional regenerative capacity of biliary epithelium and enhanced local adaptive immune cell infiltration are crucial for BD recovery. Such molecular immunological BD analyses therefore could help to predict biliary complications in cases of "major" epithelial damage after cold storage.Liver Transplantation 23 1422-1432 2017 AASLD.

Tumor-infiltrating B cells producing antitumor active immunoglobulins in resected HCC prolong patient survival

BACKGROUND & AIMS

The immunological microenvironment of HCC influences patient outcome, however, the role of B cells remains unclear. This study investigated effects of local B-cell infiltration in HCC cohorts on patient survival and immunological and molecular tumor microenvironment.

RESULTS

Unsupervised gene expression analysis of full cancer transcriptomes (N=2158) revealed a highly co-regulated immunological cluster in HCC that mainly contained immunoglobulin fragments. More specifically, in an independent patient cohort (N=242) that compares HCC with non tumorous liver tissue high expression of these B-cell associated genes was associated with better patient outcome (P=0.0149). Conclusively, the immunohistochemical analysis of another independent cohort of resected HCCs (N=119) demonstrated that infiltration of HCCs by CD20⁺ cells (P=0.004) and CD79a⁺ cells (P=0.038) at the infiltrative margin were associated with prolonged patient survival. Further, the immunoglobulin fragments that were identified in the gene expression analysis were detected at high levels in patients with dense B-cell infiltration.

METHODS

Gene expression of 2 independent HCC tissue databases was compared using microarrays. Additionally, tissue of resected HCCs was stained for CD20, CD79a and immunoglobulins and analysed for the respective cell numbers separately for tumor, infiltrative margin and distant liver stroma. These findings were correlated with clinical data and patient outcome.

CONCLUSIONS

Infiltration of HCCs by B cells is associated with prolonged patient survival. Further, a distinct B-cell like immunoglobulin profile of HCCs was identified that goes along with better patient outcome. We suggest that B cells contribute to local tumor control by secreting increased levels of immunoglobulins with antitumor activity.

Chemotherapy for metastatic colon cancer: Effect on survival when the dose is reduced due to side effects

761

Background: 5-Fluorouracil (5FU), Folinic acid (FA), and Oxaliplatin (FOLFOX) or 5FU, FA, and Irinotecan (FOLFIRI) are standard regimens for palliative chemotherapy of metastatic colon cancer. Since data showing the influence of dose reduction in palliative treatment are rare, the objective of this single center, retrospective study was to further characterize the influence of dose reduction on efficacy of these therapeutic regimens. Methods: 109 patients, diagnosed with stage IV colon cancer between 2004 and 2012 and receiving palliative first-line chemotherapy with either FOLFOX or FOLFIRI regimens in our outpatient clinic were analyzed for treatment efficacy. Patients who received dose reductions due to side effects usually received doses of 80% or lower of per protocol dose. Survival data were obtained from the Regensburg Tumor Registry. Survival analysis was performed using Kaplan-Meier statistical analysis. Results: Dose reduction was independent of age. Major reasons for dose reduction were neutropenia (30%) followed by polyneuropathy (16%) and diarrhea (14%). Dosage was more often reduced in patients receiving FOLFOX based therapy. Two-year survival of FOLFOX and FOLFIRI treated patients was comparable (35%). We observed no significant (p = 0.323) difference on two-year survival in patients receiving a reduction of chemotherapy with dose reduction (48%) compared to standard dose (31%). Further subgroup analysis did not reveal any subgroup of patients suffering from side effects with significantly worse outcome upon dose reduction. In contrast, patients who underwent dose reduction received more cycles of chemotherapy (13.7 vs. 10.8 cycles) and cumulative dosage was similar in both groups. Conclusions: A moderate reduction of chemotherapy due to side effects has no measurable effect on survival in patients with palliative colorectal cancer. This may be partially due to a longer treatment of patients with reduced chemotherapy dosage if side effects are present.

Gd-EOB-DTPA-enhanced MR relaxometry for the detection and staging of liver fibrosis

Gd-EOB-DTPA, a liver-specific contrast agent with T1-shortening effects, is routinely used in clinical routine for detection and characterization of focal liver lesions and has recently received increasing attention as a tool for the quantitative analyses of liver function. We report the relationship between the extent of Gd-EOB-DTPA- induced T1 relaxation and the degree of liver fibrosis, which was assessed according to the METAVIR score. For the T1 relaxometry, a transverse 3D VIBE sequence with inline T1 calculation was acquired prior to and 20 minutes after Gd-EOB-DTPA administration. The reduction rates of the T1 relaxation time (rrT1) between the pre- and postcontrast images were calculated, and the optimal cutoff values for the fibrosis stages were determined with receiver operating characteristic (ROC) curve analyses. The rrT1 decreased with the severity of liver fibrosis and regression analysis revealed a significant correlation of the rrT1 with the stage of liver fibrosis (r = -0.906, p < 0.001). ROC analysis revealed sensitivities ≥78% and specificities ≥94% for the differentiation of different fibrosis stages. Gd-EOB-DTPA-enhanced T1 relaxometry is a reliable tool for both the detection of initial hepatic fibrosis and the staging of hepatic fibrosis.

LDHA-Associated Lactic Acid Production Blunts Tumor Immunosurveillance by T and NK Cells

Elevated lactate dehydrogenase A (LDHA) expression is associated with poor outcome in tumor patients. Here we show that LDHA-associated lactic acid accumulation in melanomas inhibits tumor surveillance by T and NK cells. In immunocompetent C57BL/6 mice, tumors with reduced lactic acid production (Ldha^low) developed significantly slower than control tumors and showed increased infiltration with IFN-γ-producing T and NK cells. However, in Rag2^-/-γc^-/- mice, lacking lymphocytes and NK cells, and in Ifng^-/- mice, Ldha^low and control cells formed tumors at similar rates. Pathophysiological concentrations of lactic acid prevented upregulation of nuclear factor of activated T cells (NFAT) in T and NK cells, resulting in diminished IFN-γ production. Database analyses revealed negative correlations between LDHA expression and T cell activation markers in human melanoma patients. Our results demonstrate that lactic acid is a potent inhibitor of function and survival of T and NK cells leading to tumor immune escape.

Peritoneal carcinomatosis of colorectal cancer is characterized by structural and functional reorganization of the tumor microenvironment inducing senescence and proliferation arrest in cancer cells

Background : Peritoneal carcinomatosis (PC) is a terminal evolution from primary colorectal cancer (pCRC) associated with poor patient survival. Impact of the immune cell infiltrate on PC pathogenesis is unknown. Therefore, we characterized the immunological tumor microenvironment regarding proliferation, senescence and neovascularization. Methods : Formalin-fixed and paraffin-embedded (FFPE) tissue of PC and pCRC was examined by immunohistochemistry. Cells infiltrating resected tissue were isolated and analyzed by flow cytometry. PCR arrays detected the expression of genes relevant for helper T (T_H) cell responses, like T_H1, T_H2 and T_H17 response. Results : PC tumor cells demonstrate significantly lower proliferation rates than pCRC, but show significantly more senescence. PC is surrounded by significantly increased numbers of cytotoxic active Natural Killer (NK) cells, follicular helper T cells (T_FH) and B cells, whereas pCRC shows more CD4⁺ T_H cells, CD8⁺ cytotoxic T (T_C) cells, eosinophilic granulocytes, T_H17 and regulatory T (T_reg) cells. PC is characterized by significantly increased interferon-γ (IFNγ), an upregulation of tumor necrosis factor (TNF) and the NK cell-regulating cytokine interleukin-15 (IL-15). An upregulation of angiogenesis-related genes, like vascular endothelial growth factor-A (VEGF-A), leads to severe neovascularization in PC. Correlations of PC results reveal that elevated numbers of interleukin-17 (IL-17) positive cells are associated with high cancer cell proliferation, whereas high numbers of IFNγ positive cells correlate with more tumor cells in senescence. Conclusion : The cellular immune reaction is modified during metastasis, inducing senescence in PC tumor cells. Immune surveillance in PC is facilitated by NK cells and high levels of IFNγ and TNF. Counteracting this effect, T_FH and B cells combined with VEGF-A enhancement promote neovascularization in PC (Illustration 1). During metastasis from primary CRC to PC the immune cell infiltrate changes, accompanied by the induction of senescence in PC cancer cells (marked red): In pCRC, the antitumor immune response is facilitated by CD4⁺T_H cells, CD8⁺T_C cells and PRG2⁺ eosinophilic granulocytes. The premetastatic niche development is promoted by T_reg cells and T_H17 cells producing systemic factors like VEGF-A, TGF-β and TNF. Along with T_FH and B cells, as with a pro-tumor immune response, they support metastatic formation and lead to severe neovascularization in PC. This is counterbalanced by the IL-15-induced activation and proliferation of NK cells. The secreted cytokines IFNγ and TNF mediate immunosurveillance.

Basophils Trigger Fibroblast Activation in Cardiac Allograft Fibrosis Development

Fibrosis is a major component of chronic cardiac allograft rejection. Although several cell types are able to produce collagen, resident (donor-derived) fibroblasts are mainly responsible for excessive production of extracellular matrix proteins. It is currently unclear which cells regulate production of connective tissue elements in allograft fibrosis and how basophils, as potential producers of profibrotic cytokines, are involved this process. We studied this question in a fully MHC-mismatched model of heart transplantation with transient depletion of CD4(+) T cells to largely prevent acute rejection. The model is characterized by myocardial infiltration of leukocytes and development of interstitial fibrosis and allograft vasculopathy. Using depletion of basophils, IL-4-deficient recipients and IL-4 receptor-deficient grafts, we showed that basophils and IL-4 play crucial roles in activation of fibroblasts and development of fibrotic organ remodeling. In the absence of CD4(+) T cells, basophils are the predominant source of IL-4 in the graft and contribute to expansion of myofibroblasts, interstitial deposition of collagen and development of allograft vasculopathy. Our results indicated that basophils trigger the production of various connective tissue elements by myofibroblasts. Basophil-derived IL-4 may be an attractive target for treatment of chronic allograft rejection.

Immune Architecture of Colorectal Lung Metastases and Implications for Patient Survival

BACKGROUND

Pulmonary metastases occur in 10-20% of patients with colorectal cancer and significantly influence long-term survival. In this study, the immunological architecture of colorectal lung in comparison to liver metastases and its impact on patient survival were examined.

METHODS

Specimens of patients with colorectal lung and liver metastases were stained for HE, CD4, CD8, CD20, CD68 and CD45RO. Besides histomorphological evaluation, immunohistochemical stainings were analyzed for the respective cell numbers separately for tumor area, infiltrative margin and distant lung or liver stroma. These findings were correlated with clinical data and patient outcome.

RESULTS

In colorectal lung (n = 69) in comparison to liver (n = 222) metastases, the immunological focus is located in the tumor region. A high CD4+ cell infiltration of this area is associated with prolonged survival of patients after resection of colorectal lung metastases [103 ± 33 (high) vs. 37 ± 6 months (low); p = 0.0246]. Patients who were treated with preoperative chemotherapy did not show differences in immune infiltrates compared to chemotherapy-naïve patients.

CONCLUSION

Colorectal lung and liver metastases showed a distinct immunological architecture. A dense cell infiltration of colorectal lung metastases by CD4+ cells was related to prolonged patient survival. Preoperative chemotherapy did not influence cellular immune infiltrates.