Efficient Identification of Patients With NTRK Fusions Using a Supervised Tumor-Agnostic Approach

CONTEXT.—

The neurotrophic tropomyosin receptor kinase (NTRK) family gene rearrangements have been recently incorporated as predictive biomarkers in a "tumor-agnostic" manner. However, the identification of these patients is extremely challenging because the overall frequency of NTRK fusions is below 1%. Academic groups and professional organizations have released recommendations on the algorithms to detect NTRK fusions. The European Society for Medical Oncology proposal encourages the use of next-generation sequencing (NGS) if available, or alternatively immunohistochemistry (IHC) could be used for screening with NGS confirmation of all positive IHC results. Other academic groups have included histologic and genomic information in the testing algorithm.

OBJECTIVE.—

To apply some of these triaging strategies for a more efficient identification of NTRK fusions within a single institution, so pathologists can gain practical insight on how to start looking for NTRK fusions.

DESIGN.—

A multiparametric strategy combining histologic (secretory carcinomas of the breast and salivary gland; papillary thyroid carcinomas; infantile fibrosarcoma) and genomic (driver-negative non-small cell lung carcinomas, microsatellite instability-high colorectal adenocarcinomas, and wild-type gastrointestinal stromal tumors) triaging was put forward.

RESULTS.—

Samples from 323 tumors were stained with the VENTANA pan-TRK EPR17341 Assay as a screening method. All positive IHC cases were simultaneously studied by 2 NGS tests, Oncomine Comprehensive Assay v3 and FoundationOne CDx. With this approach, the detection rate of NTRK fusions was 20 times higher (5.57%) by only screening 323 patients than the largest cohort in the literature (0.30%) comprising several hundred thousand patients.

CONCLUSIONS.—

Based on our findings, we propose a multiparametric strategy (ie, "supervised tumor-agnostic approach") when pathologists start searching for NTRK fusions.

Management of psoriasis-like rash associated with idelalisib monotherapy in a patient with refractory follicular lymphoma: a case report

BACKGROUND

Follicular lymphoma is an indolent non-Hodgkin lymphoma that is most commonly diagnosed in elderly individuals. The majority of patients with follicular lymphoma present with advanced disease. Despite the recent advances in treatment, there remains a substantial unmet need for effective treatments for patients with relapsed/refractory follicular lymphoma. The PI3Kδ inhibitor idelalisib was approved by the European Medicines Agency in 2014 as a monotherapy for the treatment of adult patients with follicular lymphoma that is refractory to two prior lines of treatment. Real-world evidence from patients with follicular lymphoma treated with idelalisib indicates its utility in these patients.

CASE PRESENTATION

This case report describes an 82-year-old, retired, white, female patient with refractory follicular lymphoma who achieved a partial response with idelalisib treatment. Despite experiencing two incidences of a psoriasis-like rash during idelalisib treatment that required effective management with topical steroids, the patient was able to restart treatment successfully and maintain a continued partial response.

CONCLUSIONS

The clinical relevance of the effective management of adverse events in this case demonstrates the opportunity to enable patients to remain on therapy, thereby maintaining long-term response and improving overall outcomes.

A prospective observational study of the clinical and pathological impact of stereotactic body radiotherapy (SBRT) as a neoadjuvant strategy of chemoradiation in pancreatic cancer

PURPOSE/OBJECTIVE(S)

To improve the curative resection rates and prognoses, a variety of neoadjuvant (NA) strategies have been explored in PDAC. In our institution, non-metastatic PDACs have been treated with a NA intent with induction multiagent chemotherapy and SBRT. The primary endpoint was to increase R0 resection rate. The secondary endpoints were the analysis of the clinical tolerance, the pathological response, the local control (LC) and the OS.

MATERIALS/METHODS

All consecutive patients with non-metastatic PDAC underwent SBRT as part of the NA strategy were included. A total dose of 40-62 Gy were delivered in 5-10 fractions. Surgery was performed after SBRT and restaging.

RESULTS

Since February 2014 to December 2018, 45 patients were enrolled. Thirty-two patients underwent surgery (71.1%), 10 out of 15 were initially unresectable disease patients (66.75%). R0 resection rate was 93% (30 patients) and pN0 status was achieved in 20 patients (60.6%). Tumour regression grade (TRG): 12 patients with complete response or marked response (TRG 0-1: 37.5%), 16 patients with moderate response (TRG 2: 50%) and four patients with poor response (TRG 3: 12.5%). The median follow-up was 16.2 m (range 6.6-59.6 m) since diagnosis. The LC rate achieved was very high (95.5%). Actuarial 12 and 24 m OS was 67.4% and 35.9% respectively. No grade 3 or higher toxicity related to SBRT was observed.

CONCLUSION

The results are encouraging, suggesting that SBRT has a significant role in the management of these patients and further studies will be necessary to prove these findings.

Venous Resection for Locally Advanced Pancreatic Cancer: Time Trend and Outcome Analysis of 65 Consecutive Resections at a High-Volume Center

INTRODUCTION

Locally advanced pancreatic cancer (LAPC) is a highly malignant carcinoma with an extremely poor prognosis. Vascular venous invasion is a frequent finding in patients with pancreatic cancer. The aim of this study was to investigate the morbidity, mortality, and survival of patients with advanced pancreatic cancer.

METHODS

We retrospectively reviewed our experience of 65 consecutive pancreatic surgeries with venous resection for pancreatic cancer in three hospitals: Ramon y Cajal (Madrid, Spain) from 2002 to 2004, Monteprincipe University Hospital (Madrid, Spain) from 2005 to 2006 and Sanchinarro University Hospital (Madrid, Spain) from 2007 to December 2017. Prognostic factors were analyzed by the log-rank test and a multivariate proportional hazard regression analysis.

RESULTS

Major venous reconstruction was performed by primary lateral venorrhaphy in 11 patients (17%), primary end-to-end anastomosis in 46 (70.7%) and reconstruction with a Gore-Tex® patch (W.L. Gore & Associates, Inc., Flagstaff, AZ) in 8 (12.3%). In 58% of the patients, the pathological examination showed infiltration of the vascular specimen. About 85% of the procedures performed were R0. The perioperative morbidity rate with Dindo-Clavien classification = III was 21.5%. Tumor size and nodal status were the only prognostic variables, which significantly decreased survival by a multivariate analysis.

CONCLUSIONS

Major vascular resection to achieve macroscopic tumor clearance can be performed safely with acceptable operative morbidity and mortality. Nevertheless, it is justified only in carefully selected cases.

Interleukin-6 inhibition in the management of non-infectious uveitis and beyond

Background

Uveitis consists of a spectrum of inflammatory disorders characterized by ocular inflammation. The underlying pathophysiology consists of a complex interplay of various inflammatory pathways. Interleukin 6 is an important mediator of inflammation in uveitis and constitutes focus of research toward development of newer biological therapies in the management of non-infectious uveitis.

Main body

Pan-blockade of the inflammatory pathways with steroids is generally the first step in the management of acute non-infectious uveitis. However, long-term therapy with steroids is associated with systemic and ocular side effects, thereby necessitating the need for development of steroid sparing agents. IL-6 is a cytokine produced by various immune cells, in response to molecular patterns and affects multiple inflammatory cells. In particular, IL-6 is involved in differentiation of CD-4 cells into Th-17 cells that have been shown to play a significant role in various immune-mediated diseases such as uveitis. This broad-spectrum immunomodulatory activity makes IL-6 an excellent target for immunomodulatory therapy. Tocilizumab was the first IL-6 inhibitor to demonstrate efficacy in humans. It inhibits IL-6 from binding to both membrane-bound and soluble receptor and can be administered via intravenous (IV) and subcutaneous (SC) routes. It has been FDA approved for treatment of rheumatoid arthritis (RA) and juvenile idiopathic arthritis (JIA). Following the approval in systemic diseases, its efficacy was demonstrated in various uveitis studies including a phase 2 clinical trial (STOP-Uveitis). Overall, tocilizumab has shown a good safety profile with the risk of malignancy consistent with that expected in patients with rheumatoid arthritis. However, tocilizumab therapy has been shown to increase the risk for gastrointestinal perforation and dose-dependent neutropenia. Following the success of tocilizumab, several other agents targeting the IL-6 pathway are in the pipeline. These include sirukumab, siltuximab, olokizumab, clazakizumab, and EBI-031 which target IL-6; Sarilumab and ALX-0061 act on the IL-6 receptor.

Conclusion

Studies have shown that IL-6 inhibitors can be effective in the management of NIU. In addition, the levels of IL-6 are elevated in other ocular vascular diseases such as retinal vein occlusion and diabetic macular edema. The roles of IL-6 inhibition may be broadened in the future to include the management of retinal vascular diseases and non-uveitic macular edema.

Impact of BRCA1/2 gene mutations on survival of patients with pancreatic cancer: A case-series analysis

BRCA gene mutations are found in up to 10% of pancreatic adenocarcinoma cases. We present a description of 4 cases along with a review of the current literature regarding pathogenesis, target treatment, response and survival rates in these types of malignancies. We describe four cases of pancreatic adenocarcinoma, in three of which the BRCA2 mutation was identified, in one - BRCA1 gene alteration. Two patients underwent surgery following the neoadjuvant treatment with Folfirinox and radiotherapy; in the first case, a distal pancreatectomy with splenectomy was performed and in the second one - the Whipple's procedure. In both cases, a complete pathological response was reported. Other 2 patients were treated with Folfirinox after BRCA mutation identification and acceptable life expectancy was obtained. The association of pathologic complete response (PCR) with lower rates of local recurrence and better survival in patients with various types of adenocarcinomas is well known. Identification of such patients carrying BRCA mutations could provide an application of better personalized treatment. In some patients with pancreatic cancer, especially when there is clinical or demographic reason to suspect a genetic predisposition, a confirmation of the presence of BRCA mutations could provide an opportunity to use target treatment with beneficial outcomes regarding survival.

Blue light versus green light fundus autofluorescence in normal subjects and in patients with retinochoroidopathy secondary to retinal and uveitic diseases

PURPOSE

The aim of this study is to evaluate the differences in the fundus autofluorescence (FAF) signal between the blue light autofluorescence (BAF) from Spectralis® (Heidelberg, CA) and green light autofluorescence (GAF) 200TxTM (OPTOS, UK, in normal subjects and in patients with retinochoroidopathies (RC).

METHODS

In this prospective study, FAF was performed using BL (λ = 488 nm) and GL (λ = 532 nm) on normal subjects and patients with RC. The corresponding pairs of BAF and GAF images from both groups were analyzed using Photoshop. The strength of the FAF signal was measured on a gray scale, where optic disc was a standard to indicate absence of AF. In addition, gray values obtained from three identical points (foveal center, and points of hypo and hyper autofluorescence) in the corresponding BAF and GAF images of normal and RC subjects were divided by the optic disc value to calculate autofluorescence signal ratio (R). The R values at fovea (R1), hypoautofluorescent point (R2), and hyperautofluorescent point (R3) were compared between BAF and GAF modalities, in normal and in RC subjects separately.

RESULTS

One hundred six pairs (106 eyes) of FAF images analyzed (37 pairs: normal and 69 pairs: RC subjects). In normal subjects, the mean R1, R2, and R3 values for BAF were (1.5 ± 0.88, 1.23 ± 0.58, and 4.73 ± 2.85, respectively) and for GAF were (0.78 ± 0.20, 0.78 ± 0.20, and 1.62 ± 0.39, respectively). Similarly, in subjects with RC, the mean R1, R2, and R3 values for BAF were (1.68 ± 1.02, 1.66 ± 1.15, and 7.75 ± 6.82, respectively) and for GAF were (0.95 ± 0.59, 0.79 ± 0.45, and 2.50 ± 1.65, respectively). The mean difference in the R1, R2, and R3 ratios between BAF and GAF in normal and in RC subjects was statistically significant (p < 0.001). The strength of the correlation (r) between ratios for BAF and GAF was weak or not statistically significant in both normal and RC subjects (p > 0.05).

CONCLUSION

The distribution and intensity of the AF signal differ in BAF and GAF and cannot be used interchangeably. In BAF, optic disc signal is always weaker than in other areas, which was not true for GAF where optic disc signal was stronger than fovea and hypoautofluorescent point in both groups.

Clinical Presentation and Anatopathologic Finding of a Hepatic Vascular Hamartoma: a Case Report

HVH (hepatic vascular hamartoma) is a tumor like malformation arising from the vascular tissue of the liver. HVH has been previously reported in animals and presents distintive features from the most frequent benign tumor like malformation of the liver, the hepatic mesenchymal hamartoma (HMH). Herein we report a case of HVH localized in hepatic segment 4b, involving the gastro hepatic ligament, successfully treated with total excision. We describe the anatomo-pathologic findings focusing on the clinical and radiological presentation, the intraoperative characteristics and the differential diagnosis.

Choice of pyrolysis parameters for urban wastes affects soil enzymes and plant germination in a Mediterranean soil

The production of organic waste has steadily increased in recent years, with subsequent impact on the environment. The European Union committed to diminish the volume of biodegradable municipal waste disposed of in landfills by 2016-2020. The synthesis of biochar from urban waste and its application to improve soil quality can constitute a novel route for valorization. The aim of this paper was to study the effect of three biochars originated from pyrolysis of the organic fraction of urban waste at two different temperatures (300°C and 500°C) and two residence times (1h and 5h) on the biochemical properties of an agricultural soil. Soil was amended with biochars at a rate of 8% and incubated for 74days. A phytotoxicity assay, using garden cress as the test species, was conducted. CO₂ emissions, microbial biomass C and the enzymes dehydrogenase, phosphomonoesterase and β-glucosidase were measured in tested soils. Biochars prepared at 300°C resulted in lower germination index values, which could partly be ascribed to a higher bioavailability of heavy metals and higher soluble organic matter, while the biochar prepared as 500°C exhibited a phytostimulant effect. Biochars produced at 300°C (B300-1h, B300-5h) augmented soil CO₂ emissions while there was no effect on microbial respiration in the soil amended with the biochar prepared at 500°C. Pyrolysis temperature and, for some enzymes, residence time, controlled soil enzymatic activity.

Local allergic rhinitis is an independent rhinitis phenotype: The results of a 10-year follow-up study

BACKGROUND

The knowledge about the natural history of local allergic rhinitis (LAR) is limited. One unmet question is to demonstrate whether LAR should be considered the first step in the development of allergic rhinitis (AR) or an independent phenotype. The aim of this study was to prospectively evaluate the natural history of a population with LAR, the potential conversion to AR with systemic atopy and the development of asthma during 10 years.

METHODS

This is the second phase of a 10-year follow-up study of a cohort of 176 patients with LAR of recent onset and 115 age- and sex-matched healthy controls prospectively evaluated from 2005 to 2016. Clinical-demographic questionnaire, spirometry, skin prick test and specific IgE were evaluated yearly. Nasal allergen provocation tests (NAPT) with Dermatophagoides pteronyssinus, Alternaria alternata, Olea europaea and grass pollen were performed at baseline, and after 5 and 10 years.

RESULTS

After 10-year LAR, patients experienced a significant and clinically relevant worsening of the rhinitis, with increase in emergency assistance, development of asthma, loss of allergen tolerance and impairment of the quality of life. This worsening became significant after 5 years and progressed throughout 10 years. A similar rate of development of AR with systemic atopy was detected in patients and controls (9.7% vs 7.8%, log-rank P=.623). In 5 patients, conversion to systemic atopy occurred >10 years (3%).

CONCLUSIONS

LAR is a well-differentiated clinical entity with a low rate of development of systemic atopy, a natural evolution towards worsening and a risk factor for suffering asthma.

A comparative study of neoadjuvant treatment with gemcitabine plus nab-paclitaxel versus surgery first for pancreatic adenocarcinoma

INTRODUCTION

Neoadjuvant treatment has been reported to prolong survival in patients with potentially resectable pancreatic adenocarcinoma (PA). However, there are currently limited clinical results available using nab-paclitaxel and gemcitabine in PA. This paper compares the oncological results of patients affected by potentially resectable PA who underwent surgery first (SF) versus surgery following neoadjuvant treatment (NAT).

METHODS

This is an observational, comparative study whereby data were abstracted from a prospective database of patients affected by PA from 2007 to 2016.

RESULTS

We included a total of 81 patients (36 SF and 45 NAT) which resulted in being preoperatively similar. Among the NAT patients, treatment was well tolerated and the resection rate was 68.8% (31/45 patients). There was a trend towards a higher R1 resection rate in the SF group compared with the NAT (13.8% vs 3.2%; p = 0.1). Median overall survival in the resected NAT group was higher (30.6 vs 22.1 months; p = 0.04). In the borderline resectable group, overall survival was found to be four times higher compared with SF (43.6 versus 13.5 months; p = 0.001).

CONCLUSIONS

These data suggest that neoadjuvant treatment with gemcitabine/nab-paclitaxel is a safe and effective option for potentially resectable PA compared with the SF approach.

Pancreatic disease, panniculitis, polyarthrtitis syndrome successfully treated with total pancreatectomy: Case report and literature review

INTRODUCTION

Pancreatic disease can be complicated by extrabdominal manifestations such as panniculitis and polyarthritis. The symptomatic triad comprising pancreatic disease, panniculitis and polyarthritis is also known as PPP syndrome and is characterized by severe chronic sequels and high mortality rate. We describe a case of PPP syndrome successfully treated with spleen preserving total pancreatectomy; in addition we performed a literature review.

PRESENTATION OF CASE

A 67 years old male presented panniculitis and polyarthritis without clinical abdominal symptoms. Clinical presentation, laboratory values and radiological findings demonstrated an acute pancreatitis and a pancreatic cancer was suspected; failure of conservatory treatments and high suspicious of malignancy led to perform a spleen preserving total pancreatectomy. Finally histological examination excluded a pancreatic cancer and confirmed a chronic pancreatitis. Patient was discharged with complete resolution of the extrabdominal disease.

DISCUSSION

In literature only 64 cases of PPP syndrome have been reported. Abdominal symptoms do not often appear at presentation and diagnosis may be delayed. Panniculitis develope in any part of the body but especially on the distal parts of the lower extremities, around the ankles and pretibial regions of the legs. Between osteo-articular manifestations polyarthritis is the most common one, although oligoarthritis, and monoarthritis in have been reported.

CONCLUSION

PPP syndrome is a rare disease with a high mortality rate. A timely diagnosis and an aggressive treatment may improve the prognosis of this condition.

Preoperative treatment with gemcitabine plus nab-paclitaxel is a safe and effective chemotherapy for pancreatic adenocarcinoma

INTRODUCTION

Recently, novel chemotherapeutic agents like nab-paclitaxel and gemcitabine demonstrated a survival benefit over gemcitabine alone in metastatic pancreatic cancer. However, there are limited clinical results using this chemotherapy in potentially resectable pancreatic adenocarcinoma. Our aim is to report the oncological results of patients affected by potentially resectable pancreatic adenocarcinoma that underwent surgery after a combination of gemcitabine and nab-paclitaxel.

METHODS

A total of 25 patients have been included. We evaluated: (1) Drug toxicity; (2) tumoral response (tumoral size at CT scan, SUV of FDG PET-CT scan and CA 19.9; (3) resection rate; (4) R0 resection rate and histopathological response and (5) survival and disease free survival.

RESULTS

Overall treatment was well tolerated. Treatment resulted in a statistical decrease of CA19-9 (p = 0.019) tumoral size (p = 0.04) and SUV (p = 0.004). The resection rate was 68% (17/25 patients). All specimens were R0 and 13 of 17 specimens had major pathological regressions (complete and important response). Median survival and medial disease free survival of patients that underwent surgery was 21 months and 19 months, respectively at a mean follow up of 38.5 months.

CONCLUSIONS

This data suggests that nab-paclitaxel and gemcitabine is a safe and effective neoadjuvant treatment for potentially resectable pancreatic adenocarcinoma. This promising data should be confirmed in larger, randomized studies.

SPARC Expression Did Not Predict Efficacy of nab-Paclitaxel plus Gemcitabine or Gemcitabine Alone for Metastatic Pancreatic Cancer in an Exploratory Analysis of the Phase III MPACT Trial

PURPOSE

nab-Paclitaxel plus gemcitabine was superior to gemcitabine alone for patients with metastatic pancreatic cancer (MPC) in the phase III MPACT trial. This study evaluated the association of secreted protein acidic and rich in cysteine (SPARC) levels with efficacy as an exploratory endpoint.

EXPERIMENTAL DESIGN

Patients with previously untreated MPC (N = 861) received nab-paclitaxel plus gemcitabine or gemcitabine alone. Baseline SPARC level was measured in the tumor stroma and epithelia (archival biopsies) and plasma. Experiments were performed in pancreatic cancer mouse models in which SPARC was intact or deleted.

RESULTS

SPARC was measured in the tumor stroma of 256 patients (30%), the tumor epithelia of 301 patients (35%), and plasma of 343 patients (40%). Stroma-evaluable samples were from metastases (71%), from the pancreas (11%), or of unidentifiable origin (insufficient tissue to determine; 17%). For all patients, stromal SPARC level [high (n = 71) vs. low (n = 185)] was not associated with overall survival (OS; HR, 1.019; P = 0.903); multivariate analysis confirmed this lack of association. There was no association between stromal SPARC level and OS in either treatment arm. Neither tumor epithelial SPARC nor plasma SPARC was associated with OS. Results from a SPARC knockout mouse model treated with nab-paclitaxel plus gemcitabine revealed no correlation between SPARC expression and tumor progression or treatment efficacy.

CONCLUSIONS

SPARC levels were not associated with efficacy in patients with MPC. This exploratory analysis does not support making treatment decisions regarding nab-paclitaxel plus gemcitabine or gemcitabine alone in MPC based on SPARC expression.

Detection of actionable oncogene drivers alterations in HER2-amplified gastric cancer by next generation sequencing

67

Background: HER2 amplified cases are the only subset of gastric carcinoma (GC) patients with an approved targeted therapy (≈20%). In GC it is still unknown if there is a mutually exclusive pattern of mutations in major driver oncogenes. We performed a systematic search for targetable oncogenes in a cohort of HER2 amplified GC patients. Methods: 53 Formalin-fixed paraffin embedded samples from HER2 amplified GC patients (43 tumor and 10 normal samples) were selected for next generation sequencing (NGS). Before DNA extraction a macrodissection procedure was performed to guarantee at least 30% tumor in all cases. DNA samples were sequenced using the Ion Torrent Personal Genome Machine (PGM) sequencing platform (Life Technologies, Carlsbad, CA, USA). The Ion AmpliSeq Cancer Hotspot Panel v2 was used. This panel encompasses more than 2800 mutational hotspots of 50 oncogenes and tumor suppressor genes. Data were processed using the Ion Torrent platform-specific pipeline software Torrent suite v4.2. Moreover, sequencing data were analyzed with Ion Reporter software 4.2 to detect any copy number alteration of the genes included in the panel. Results: We successfully sequenced all samples. We identified 89 mutations in 12 genes (range from 1 ~ 9). The most frequent significant mutations included TP53 mutations (30), PI3KCA (3), SMAD4 (3), CDKN2A (4), CTNNB1 (3) and MET (3). Other mutations were found in KRAS, NOTCH, APC, and VHL genes. We also detected potential amplifications in the KRAS (4), EGFR (9), PI3KCA (11), AKT (6), FGFR (6), CDKN2A (4) and CDH1(8) genes. Among 43 tumor specimens, 86% of specimens harbored at least one genetic alteration, most of them linked to actionable mutations or amplifications Conclusions: Within HER2 amplified GCs, there are additional subsets with a potentially targetable oncogene. Future testing for these targets will benefit from including HER2 amplified GC patients Supported by the Spanish Ministry of Health, Fondo de Investigaciones Sanitarias grant PI11/01005 and European FEDER (PN I+D+I 2008‐20011).

Sources of blood meals of sylvatic Triatoma guasayana near Zurima, Bolivia, assayed with qPCR and 12S cloning

Background

In this study we compared the utility of two molecular biology techniques, cloning of the mitochondrial 12S ribosomal RNA gene and hydrolysis probe-based qPCR, to identify blood meal sources of sylvatic Chagas disease insect vectors collected with live-bait mouse traps (also known as Noireau traps). Fourteen T. guasayana were collected from six georeferenced trap locations in the Andean highlands of the department of Chuquisaca, Bolivia.

Methodology/Principal Findings

We detected four blood meals sources with the cloning assay: seven samples were positive for human (Homo sapiens), five for chicken (Gallus gallus) and unicolored blackbird (Agelasticus cyanopus), and one for opossum (Monodelphis domestica). Using the qPCR assay we detected chicken (13 vectors), and human (14 vectors) blood meals as well as an additional blood meal source, Canis sp. (4 vectors).

Conclusions/Significance

We show that cloning of 12S PCR products, which avoids bias associated with developing primers based on a priori knowledge, detected blood meal sources not previously considered and that species-specific qPCR is more sensitive. All samples identified as positive for a specific blood meal source by the cloning assay were also positive by qPCR. However, not all samples positive by qPCR were positive by cloning. We show the power of combining the cloning assay with the highly sensitive hydrolysis probe-based qPCR assay provides a more complete picture of blood meal sources for insect disease vectors.

The World Health Organization (WHO) estimates that 7 to 8 million people are currently infected with Trypanosoma cruzi, the parasite that causes Chagas disease. The WHO recommends insect vector control as the primary prevention method; and insecticide spraying is the most commonly used intervention technique. Sylvatic insect vectors are a special concern because they are a source of reinfestation after insecticides have been applied to living quarters (domestic) and immediate surroundings (peridomestic). To better understand sylvatic insect vector movement, we used two molecular biology techniques to detect the blood meal sources of sylvatic insect vectors. The first technique, cloning of 12S PCR products, allows us to cast a wide net and detect blood meal sources with no previous knowledge of vertebrates or mammals in the study site. After acquiring knowledge of vertebrates in the study site (either through the aforementioned cloning technique, literature review or survey of the area), the second technique, the species-specific hydrolysis probe-based qPCR provides a highly sensitive assay for particular taxa.

Robotic versus laparoscopic rectal resection: is there any real difference? A comparative single center study

INTRODUCTION

Robotic surgery has gained worldwide acceptance in the past decade, and several studies have shown that this technique is safe and feasible. The aim of this study is to compare main outcomes of laparoscopic and robotic rectal resection.

METHODS

In total, 143 consecutive patients treated for rectal cancer in our department with laparoscopic or robotic-assisted surgery from October 2010 to July 2013 were retrospectively analyzed.

RESULTS

A total of 87 patients underwent laparoscopic rectal resection, and 56 patients were treated using a robotic approach. The conversion rate was 11.5% in the laparoscopic group and 3.5% in the robotics group (P =  0.09). The low rectal cancer conversion rate was significantly lower in the robotic group (1.8%) than in the laparoscopy group (9.2%) (P = 0.04). Mean operation time was 252 min in the laparoscopic group and 309 min in the robotic group (P =  0.023).

CONCLUSIONS

The robotic approach shows a lower conversion rate in low rectal cancer but with a longer operative time compared with the laparoscopic technique.

Recommendations of a group of experts for the pathological assessment of tumour regression of liver metastases of colorectal cancer and damage of non-tumour liver tissue after neoadjuvant therapy

Colorectal cancer (CRC) incidence has increased during the past decades in Spain, being the first malignant tumour in incidence. Observed mortality for CRC is mainly due to liver and lung metastases. The only curative treatment is surgery; new surgical techniques and neoadjuvant treatments have increased the number of surgery candidate patients. Patients should be managed with a multidisciplinary approach that includes imaging techniques, chemotherapy, surgery and pathological assessment. As an answer to this approach, a group of pathology experts interested on CRC liver metastases aimed to review the diagnosis and prognosis of liver mestastases and developed practical recommendations for its assessment. The expert group revised the current literature and prepared questions to be discussed based on available evidence and on their clinical practise. As a result, recommendations for the assessment of tumour regression of liver metastases are proposed, which could be implemented in oncology centres allowing assessment standardisation for these patients. Prospective multi-center studies to evaluate these recommendations validity will further contribute to improve the standard care of CRC liver metastases patients.

Stromal disrupting effects of nab-paclitaxel in pancreatic cancer

Background:

Nab-paclitaxel and gemcitabine have demonstrated a survival benefit over gemcitabine alone in advanced pancreatic cancer (PDA). This study aimed to investigate the clinical, biological, and imaging effects of the regimen in patients with operable PDA.

Methods:

Patients with operable PDA received two cycles of nab-paclitaxel and gemcitabine before surgical resection. FDG-PET and CA19.9 tumour marker levels were used to measure clinical activity. Effects on tumour stroma were determined by endoscopic ultrasound (EUS) elastography. The collagen content and architecture as well as density of cancer-associated fibroblasts (CAFs) were determined in the resected surgical specimen and compared with a group of untreated and treated with conventional chemoradiation therapy controls. A co-clinical study in a mouse model of PDA was conducted to differentiate between the effects of nab-paclitaxel and gemcitabine.

Results:

A total of 16 patients were enrolled. Treatment resulted in significant antitumour effects with 50% of patients achieving a >75% decrease in circulating CA19.9 tumour marker and a response by FDG-PET. There was also a significant decrement in tumour stiffness as measured by EUS elastography. Seven of 12 patients who completed treatment and were operated had major pathological regressions. Analysis of residual tumours showed a marked disorganised collagen with a very low density of CAF, which was not observed in the untreated or conventionally treated control groups. The preclinical co-clinical study showed that these effects were specific of nab-paclitaxel and not gemcitabine.

Conclusion:

These data suggest that nab-paclitaxel and gemcitabine decreases CAF content inducing a marked alteration in cancer stroma that results in tumour softening. This regimen should be studied in patients with operable PDA.

Phase II trial of target-guided personalized chemotherapy in first-line metastatic colorectal

3543

Background: Chemotherapy (Ch) options for patients (pts) with colorectal cancer (CRC) have increased in the last years. However, there are no validated prospective molecular markers in CRC to select which agents are better to treat any individual case. The aim of this study was to determine the efficacy in terms of progression free survival (PFS) of a biomarker panel to guide treatment selection in this setting. Methods: Treatment naive, ECOG 0-1, metastatic CRC pts were accrued. Pts were prospectively analyzed with a predefined set of 10 molecular targets, including: KRAS, BRAF, and PI3K mutations and Topoisomerase-1(Top-1), ERCC-1, Thymidylate synthase (TS) and Thymidine phosphorylase (TP) expression by inmunohistochemistry ( IHC) performed in a tumor biopsy. Ch combination schema plus Cetuximab (C) or Bevacizumab (B) at standard doses was customized based on: Topo-1 +:Irinotecan (I). Topo-1- and ERCC-1 -:Oxaliplatin(O). Topo-1- and ERCC1 +:investigator option (I or O). TS -:Fluoropyrimidines (FP).TS +:No FP. TP -:5-FU, TP +:Capecitabine. Maintenance C or B treatment was allowed. Primary outcome measure was PFS. Results: 74 pts were accrued and all of them received biomarker guide treatment. All of them began personalized. Interim analysis on 61 pts (38 males, median age 65) showed.Topo-1 + in 33 pts (54%),ERCC-1- in 36( 59%) TS + in 44 (73%), TP – in 61 ( 100%), K-ras nativein 34 ( 55%), BRaf mutated in 2 (3,2%). With a median follow up time of 9,1 months (m). Median PFS (95% CI) is 8,6 (6,2-10,9) m, with a 41,3% (27,4-55,2) 12mPFS . Overall clinical benefit (Response + Stabilizations) was 74,5% (65,6-83,4).Toxicities Grade ≥ 3 included 18% neutropenia, 4,9% asthenia and 3,3% anemia. 12 pts (23%) received loco-regional treatment ( surgery or radiosurgery). Median Overall survival has not been reached. Conclusions: Target- Guided Personalized Ch in first line CRC pts is feasible and results in promising PFS with low toxicity. Update of final results and more detailed data will be presented. Clinical trial information: NCT01453257.

A comparison of EGFR mutation testing methods in lung carcinoma: direct sequencing, real-time PCR and immunohistochemistry

The objective of this study is to compare two EGFR testing methodologies (a commercial real-time PCR kit and a specific EGFR mutant immunohistochemistry), with direct sequencing and to investigate the limit of detection (LOD) of both PCR-based methods. We identified EGFR mutations in 21 (16%) of the 136 tumours analyzed by direct sequencing. Interestingly, the Therascreen EGFR Mutation Test kit was able to characterize as wild-type one tumour that could not be analyzed by direct sequencing of the PCR product. We then compared the LOD of the kit and that of direct sequencing using the available mutant tumours. The kit was able to detect the presence of a mutation in a 1% dilution of the total DNA in nine of the 18 tumours (50%), which tested positive with the real-time quantitative PCR method. In all cases, EGFR mutation was identified at a dilution of 5%. Where the mutant DNA represented 30% of the total DNA, sequencing was able to detect mutations in 12 out of 19 cases (63%). Additional experiments with genetically defined standards (EGFR ΔE746-A750/+ and EGFR L858R/+) yielded similar results. Immunohistochemistry (IHC) staining with exon 19-specific antibody was seen in eight out of nine cases with E746-A750del detected by direct sequencing. Neither of the two tumours with complex deletions were positive. Of the five L858R-mutated tumours detected by the PCR methods, only two were positive for the exon 21-specific antibody. The specificity was 100% for both antibodies. The LOD of the real-time PCR method was lower than that of direct sequencing. The mutation specific IHC produced excellent specificity.

Antitumor activity of nab-paclitaxel and gemcitabine in resectable pancreatic cancer

4040

Background: Nab-paclitaxel in combination with gemcitabine has shown interesting clinical activity in patients with advanced pancreatic cancer (PDA) likely related to its ability to eliminate pancreas cancer stroma. In this study we explore clinical and pathological effects of the combination in patients with operable PDA. Methods: Patients with resectable o borderline resectable pancreatic cancer were treated with gemcitabine(1000mg/m2 days 1, 8 and 15) and nab-paclitaxel(125mg/m2 days 1, 8 and 15) for two cycles prior to surgery. Response was assessed by FDG-PET, CA199 levels and elastography, an EUS-based non invasive assessment of tumor stroma. Results: 16 patients were included into the study. 2 patients (12.5%) showed a progression disease (both with hepatic metastases) and were not operated. Median value for PET SUVmax decreased from 7,1 pre-treatment to 4,6 post-treatment(p=0.004), including 7(50%) of patients with a partial metabolic response and the mean CA199 decreased from 2654 to 52(p=0.02) with 43% patients having a more that 75 % decrement in tumor marker. The elastography ratio value diminished from 36 pre-treatment to 18 post-treatment(p=0.003) and correlated with improvement in SUVmax(p=0.04) and CA199 response(p=0,07). Grade 3-4 toxicities were neutropenia in 18% (none febrile neutropenia), thrombocytopenia in 12.5 and 6.2% transaminase elevation. So far 9 patients have been operated and in 8(89%) a complete resection (R0) was achieved. 1 patient had a complete pathological response and 4 patients had near complete responses with only a few(< 5%) residual tumor. In-depth analysis of stromal composition after treatment showed, compared to a series of 10 cases untreated and treated with conventional chemoradiation, decreased myofibroblast content, increase vessel density and distorted collagen fibers. Conclusions: Neoadjuvant treatment with gemcitabine plus nab-paclitaxel is feasible and results in significant clinical activity. Non-invasive elastography appears and attractive method to monitor tumor response. The rate of pathological responses and R0 resections in substantial for this setting. Biological studies of resected specimens show unique effects in tumor stroma.

Influence of humified organic matter on copper behavior in acid polluted soils

The main purpose of this work was to identify the role of soil humic acids (HAs) in controlling the behavior of Cu(II) in vineyard soils by exploring the relationship between the chemical and binding properties of HA fractions and those of soil as a whole. The study was conducted on soils with a sandy loam texture, pH 4.3-5.0, a carbon content of 12.4-41.0gkg(-1) and Cu concentrations from 11 to 666mgkg(-1). The metal complexing capacity of HA extracts obtained from the soils ranged from 0.69 to 1.02molkg(-1), and the stability constants for the metal ion-HA complexes formed, logK, from 5.07 to 5.36. Organic matter-quality related characteristics had little influence on Cu adsorption in acid soils, especially if compared with pH, the degree of Cu saturation and the amount of soil organic matter.

Variability in As, Ca, Cr, K, Mn, Sr, and Ti concentrations among humic acids isolated from peat using NaOH, Na4P2O7 and NaOH+Na4P2O7 solutions

Sphagnum peat has been found to efficiently remove heavy metals, oil, detergents, dyes, pesticides and nutrients from contaminated waters since its major constituents, i.e., unesterified polyuronic acids, cellulose, and fulvic and humic acids (HA), show functional groups (e.g., alcohols, aldehydes, carboxylic acids, ketones and phenolic hydroxides) which may adsorb pollutant species. The influence of the extractant on the analytical characteristics of HA is an old but still open topic that should be studied in relation to the nature of the matrix from which they originate. While a number of works have been published on the effects of different reagents on the extraction yields and structural properties of HA from soils, relatively little attention has been devoted to peat HA. In this work, the contents of some major and trace elements (As, Ca, Cr, K, Mn, Sr, and Ti) in five Sphagnum-peat samples and in their corresponding HA fractions isolated using three common extractant solutions, i.e., 0.5M NaOH, 0.1M Na(4)P(2)O(7), and 0.5M NaOH+0.1M Na(4)P(2)O(7), where investigated by X-ray fluorescence spectroscopy. In general, Cr, Mn, and Ti concentrations of bulk peat samples were higher than those of the corresponding HA fractions regardless of the extractant used. Arsenic, Ca, K, and Sr concentrations in the HA fractions were affected by the extraction procedure, although at different extents depending on the extractant utilized. In particular, compared to both NaOH and NaOH+Na(4)P(2)O(7), the Na(4)P(2)O(7) extractant yielded HA generally richer in As, Ca, K, and Sr, and poorer in Ti. These results may be related to both the nature of each HA fraction and the physical and chemical form of each element supplied to the studied bog via atmospheric deposition.