The expression of PTEN is associated with improved prognosis in patients with ampullary adenocarcinoma after pancreaticoduodenectomy

Semiquantitative assessment of phosphatase and tensin homolog value with immunohistochemistry in colorectal cancer

INTRODUCTION

Colorectal cancer has emerged as a concerning health problem, ranking the third most common form of cancer in both men and women. The phosphatase and tensin homologue (PTEN) protein is widely known for its role as an inhibitor of the phosphatidylinositol 3-kinase/protein kinase-B/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway, playing a major role inhibiting tumor development. Previous studies investigated the role of this protein in the PI3K pathway and how it affected colorectal cancer. However, a standardized cut-off value for PTEN expression has not been established.

METHODS

Immunohistochemistry was used in examining PTEN. The staining grade ranging from 0 to 3 was then multiplied by the number of 100 cancer cells counted, with total score between 0 and 300. In this study, receiver operating characteristic (ROC) curve was employed to determine the expression cut-off value for PTEN in colorectal cancer.

RESULTS

This study showed statistically significant results (P < 0.001) in either tumor or non-tumor tissues by using the ROC curve with a cut-off value of 199.0. This study also revealed significant correlation between nodal status with PTEN (P = 0.008) and stage with PTEN (P = 0.019) with sensitivity 0.753 and specificity 0.728.

CONCLUSION

Semiquantitative assessment with cell counting multiplied by color intensity is a good method in determining PTEN expression. The use of immunohistochemical staining intensity and cell scoring with ROC cut-off is effective to elaborate the effects of PTEN in colorectal cancer (PTEN value > 199.0 was classified as strong and ≤ 199.0 as weak).

Molecular pathways in periampullary cancer: An overview

Molecular alterations in oncogenes and tumor suppressors in various signaling pathways are basis for personalized therapy in cancer. Periampullary carcinoma behaves differently from pancreatic carcinoma both in prognosis and outcome, therefore it needs special attention. Pancreatic cancer have higher incidence of nodal spread and perineural &lymphovascular invasion suggesting it biologically more aggressive tumor compared to periampullary cancer. Since PAC tumors consist of heterogenous tissue of origin, they might contain different mutations in tumor associated genes and other changes in tissue composition among different subgroups clubbed together. Significant progress has been made in understanding the molecular nature of PAC in the previous two decades, and a large number of mutations and other genetic changes have been identified as being responsible for the disease. This review article targets to collate and discuss the molecular evolution of PAC and their implication in its outcome. As per literature, mitogen-activated protein kinase (MAPK), phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K), and Wnt signaling are the most common pathways involved in PAC. Mutations in KRAS, TP53, CTNNB1, SMAD4 and APC genes were the most frequently reported. I-subtype resembles colorectal cancer while the morphology of PB-type shows close resemblance to pancreatic tumors. The frequency of driver gene mutations is higher in I-type compared to PB-type of PAC indicating I-type to be genetically more unstable. The genetic landscape of PAC obtained from WES data highlighted PI3/AKT pathway to be a primary target in I-type and RAS/RAF in PB-type.

Survival after curative pancreaticoduodenectomy for ampullary adenocarcinoma in a South American population: A retrospective cohort study

BACKGROUND

Ampullary adenocarcinoma (AAC) is a rare neoplasm that accounts for only 0.2% of all gastrointestinal cancers. Its incidence rate is lower than 6 cases per million people. Different prognostic factors have been described for AAC and are associated with a wide range of survival rates. However, these studies have been exclusively conducted in patients originating from Asian, European, and North American countries.

AIM

To evaluate the histopathologic predictors of overall survival (OS) in South American patients with AAC treated with curative pancreaticoduodenectomy (PD).

METHODS

We analyzed retrospective data from 83 AAC patients who underwent curative (R0) PD at the National Cancer Institute of Peru between January 2010 and October 2020 to identify histopathologic predictors of OS.

RESULTS

Sixty-nine percent of patients had developed intestinal-type AAC (69%), 23% had pancreatobiliary-type AAC, and 8% had other subtypes. Forty-one percent of patients were classified as Stage I, according to the AJCC 8th Edition. Recurrence occurred primarily in the liver (n = 8), peritoneum (n = 4), and lung (n = 4). Statistical analyses indicated that T3 tumour stage [hazard ratio (HR) of 6.4, 95% confidence interval (CI) of 2.5-16.3, P < 0.001], lymph node metastasis (HR: 4.5, 95%CI: 1.8-11.3, P = 0.001), and pancreatobiliary type (HR: 2.7, 95%CI: 1.2-6.2, P = 0.025) were independent predictors of OS.

CONCLUSION

Extended tumour stage (T3), pancreatobiliary type, and positive lymph node metastasis represent independent predictors of a lower OS rate in South American AAC patients who underwent curative PD.

Ampullary carcinoma-A genetic perspective

Ampulla of vater carcinoma (AVC) is a rare gastrointestinal tumour that is associated with a high mortality rate and it's often diagnosed at later stages due to lack of clinical symptoms. Early diagnosis of this condition is essential to effectively treat patients for better prognosis. A significant amount of advancement has been made in understanding the molecular nature of cancer in the past decade. A substantial number of mutations and alterations have been detected in various tumors. Despite the occurrence of AVC across the globe, the number of studies conducted on this tumor type remains low; this is largely due to its rare occurrence. Moreover, AVC tissues are complex and contain mutations in oncogenes, tumour suppressors, apoptotic proteins, cell proliferation proteins, cell signaling proteins, transcription factors, chromosomal abnormalities and cellular adhesion proteins. The frequently mutated genes included KRAS, TP53 and SMAD4 and are associated with prognosis. Several molecules of the PI3K, Wnt signaling, TGF-beta pathway and cell cycle have also been altered in AVCs. This review comprises of all the genetic mutations, associated pathways and related prognosis that are involved in AVCs from the year 1989 to 2017. This report can be used as a stepping-stone to establish biomarkers for early diagnosis of AVC and to discover molecular targets for drug therapy.

Proposed new staging system for ampulla of Vater cancer with greater discriminatory ability: multinational study from eastern and western centers

BACKGROUND

We built a multinational retrospective database of patients with ampulla of Vater cancer to develop a reliable new staging system.

METHOD

This study included 841 patients with ampulla of Vater cancer after curative surgery at Seoul National University Hospital (n = 440) and Johns Hopkins University medical institutions (n = 401) between 1985 and 2013.

RESULTS

The 5-year overall survival (OS) rates of patients staged according to the 7^th American Joint Committee on Cancer staging system were 80.3%, 60.9%, 58.1%, 36.6%, 17.9%, and 25.0% for Stages IA (n = 140), IB (n = 194), IIA (n = 115), IIB (n = 348), III (n = 33), and IV (n = 4), respectively. Five-year OS rates were similar in patients with Stage IB (T2N0M0) and IIA (T3N0M0) tumors (P = 0.556), but differed significantly between other pairs of groups. The number of positive lymph nodes (PLN) enhanced prognosis when stratified as 0, 1-2 and ≥3 (P < 0.001). The revised staging system consisted of Stages I (T1, PLN 0), IIA (T2-T3, PLN 0), IIB (T1-T3, PLN 1-2), III (PLN ≥3 or any T4), and IV (any M1), with 5-year OS rates differing significantly in each pair of groups, including Stages I and IIA (P < 0.001).

CONCLUSION

This new staging system has better discriminatory ability in stratifying 5-year OS rates based on a large multinational database.

Immunohistochemical analysis of PTEN, HER2/neu, and ki67 expression in patients with gastric cancer and their association with survival

BACKGROUND

Considering the poor prognosis of patients with gastric cancer, molecular diagnostic and prognostic markers for this cancer should be established. The aims of our study were to assess the correlations between PTEN, HER2/neu, and Ki67 expressions and clinicopathological factors of gastric cancer patients in upper Egypt, as well as their influence on OS and DFS.

PATIENTS AND METHODS

In this descriptive-analytic study, 42 patients with gastric carcinoma treated by postioerative chemoradiation between 2004 and 2014. Pathological review was done. Immunohistochemical staining and evaluation were performed.

RESULTS

All the studied markers were significantly correlated with increased TNM stage. Her2/neu overexpression and positive Ki67 expression were significantly associated with histological grade. High percentage of positive Her2/neu and Ki67expression was found in gastric carcinoma tissue samples which lack PTEN expression. The one-year OS rate for the entire group (n=42) was 77.4%, whereas the DFS rate was 45%. Pathological T stage PTEN status significantly affected both OS (p=0.029 and 0.027 respectively) and DFS (p=0.006 and 0.012 respectively) rates. Multivariate Cox analyses showed that only pathological T stage was an independent prognostic factor affecting OS (P=0. 007, HR: 2.02; 95% CI: 1.2-3.38)and DFS(P<0.0001, HR: 2.69; 95% CI: 1.54-4.69).

CONCLUSION

All the studied molecular markers, was significantly correlated with pathological T stage that significantly affected both OS and DFS rates. These findings indicate that these markers have an important role in gastric cancer growth and dissemination so these markers can be used as a prognostic biomarker. In addition, therapies targeting Her2 and PTEN may help develop novel therapeutics for gastric cancer.

Advances in biomarkers of biliary tract cancers

Tumor biomarkers can be applied for early diagnosis or precise treatment, thereby leading to personalized treatment and better outcomes. Biliary tract cancers (BTCs) are a group of cancers that occurs in different locations and have different clinical or genetic properties. Though the incidence of BTCs is rare, BTCs are among the most lethal cancers in the world and all have very low 5-year survivals. Lack of efficient early diagnostic approaches or adjuvant therapies for BTCs are main reasons. These urge us to broaden the researches into BTC biomarkers. Although few progresses of diagnostic biomarkers for BTCs have been achieved, there are still some advances in prognostic, predictive and therapeutic areas. In this review, we will focus on these achievements.

Substaging Nodal Status in Ampullary Carcinomas has Significant Prognostic Value: Proposed Revised Staging Based on an Analysis of 313 Well-Characterized Cases

BACKGROUND

Current nodal staging (N-staging) of ampullary carcinoma in the TNM staging system distinguishes between node-negative (N0) and node-positive (N1) disease but does not consider the metastatic lymph node (LN) number.

METHODS

Overall, 313 patients who underwent pancreatoduodenectomy for ampullary adenocarcinoma were categorized as N0, N1 (1-2 metastatic LNs), or N2 (≥3 metastatic LNs), as proposed by Kang et al. Clinicopathological features and overall survival (OS) of the three groups were compared.

RESULTS

The median number of LNs examined was 11, and LN metastasis was present in 142 cases (45 %). When LN-positive cases were re-classified according to the proposed staging system, 82 were N1 (26 %) and 60 were N2 (19 %). There was a significant correlation between proposed N-stage and lymphovascular invasion, perineural invasion, increased tumor size (each p < 0.001), and surgical margin positivity (p = 0.001). The median OS in LN-negative cases was significantly longer than that in LN-positive cases (107.5 vs. 32 months; p < 0.001). Patients with N1 and N2 disease had median survivals of 40 and 24.5 months, respectively (p < 0.0001). In addition, 1-, 3-, and 5-year survivals were 88, 76, 62 %, respectively, for N0; 90, 55, 31.5 %, respectively, for N1; and 68, 34, 30 %, respectively for N2 (p < 0.001). Even with multivariate modeling, the association between higher proposed N stage and shorter survival persisted (hazard ratio 1.6 for N1 and 1.9 for N2; p = 0.018).

CONCLUSIONS

Classification of nodal status in ampullary carcinomas based on the number of metastatic LNs has a significant prognostic value. A revised N-staging classification system should be incorporated into the TNM staging of ampullary cancers.

Immunophenotyping of ampullary carcinomata allows for stratification of treatment specific subgroups

BACKGROUND

Ampullary carcinomata (AC) can be separated into intestinal (IT) or pancreatobiliary (PB) subtypes. Although morphological, immunohistochemical and molecular differentiation of IT and PB have been well documented; the prognostic significance of histological subtype and whether patients with either subtype benefit from differential chemotherapeutic regimens remains unclear.

METHODS

As part of a larger cohort study, patients who underwent resection for AC or pancreatic ductal adenocarcinoma (PDAC) were retrospectively identified. Clinicopathological covariates and outcome were obtained and MUC1, MUC2, CDX2 and CK20 were assessed with immunohistochemistry.

RESULTS

Of 99 ACs, the resultant immunophenotypes indicated 48% and 22% were IT and PB, respectively. Thirty (30%) cases were quadruple negative (QN). Within the PDAC cohort (N = 257), the most prevalent immunophenotype was QN (53%). Subsequently, all QN ACs were classified as PB immunohistochemically yielding 47.5% and 52.5% classified as IT and PB, respectively. Involved regional lymph nodes and elevated T-stage were significantly associated with PB compared with IT AC (p = 0.0032 and 0.0396, respectively). Progression-free survival revealed inferior survival for PB versus IT AC (p = 0.0156).

CONCLUSIONS

AC can be classified into prognostic groups with unique clinicopathological characteristics using immunohistochemistry. Immunophenotypical similarity of PB and PDAC suggests that treatment regimens similar to those used in PDAC should be explored.

Phase II Pilot Study of Vemurafenib in Patients With Metastatic BRAF-Mutated Colorectal Cancer

Purpose

BRAF V600E mutation is seen in 5% to 8% of patients with metastatic colorectal cancer (CRC) and is associated with poor prognosis. Vemurafenib, an oral BRAF V600 inhibitor, has pronounced activity in patients with metastatic melanoma, but its activity in patients with BRAF V600E–positive metastatic CRC was unknown.

Patients and Methods

In this multi-institutional, open-label study, patients with metastatic CRC with BRAF V600 mutations were recruited to an expansion cohort at the previously determined maximum-tolerated dose of 960 mg orally twice a day.

Results

Twenty-one patients were enrolled, of whom 20 had received at least one prior metastatic chemotherapy regimen. Grade 3 toxicities included keratoacanthomas, rash, fatigue, and arthralgia. Of the 21 patients treated, one patient had a confirmed partial response (5%; 95% CI, 1% to 24%) and seven other patients had stable disease by RECIST criteria. Median progression-free survival was 2.1 months. Patterns of concurrent mutations, microsatellite instability status, CpG island methylation status, PTEN loss, EGFR expression, and copy number alterations were not associated with clinical benefit. In contrast to prior expectations, concurrent KRAS and NRAS mutations were detected at low allele frequency in a subset of the patients' tumors (median, 0.21% allele frequency) and were apparent mechanisms of acquired resistance in vemurafenib-sensitive patient-derived xenograft models.

Conclusion

In marked contrast to the results seen in patients with BRAF V600E–mutant melanoma, single-agent vemurafenib did not show meaningful clinical activity in patients with BRAF V600E mutant CRC. Combination strategies are now under development and may be informed by the presence of intratumor heterogeneity of KRAS and NRAS mutations.

Expression and clinical significance of epidermal growth factor receptor and insulin-like growth factor receptor 1 in patients with ampullary adenocarcinoma

Epidermal growth factor receptor (EGFR) and insulin-like growth factor receptor 1 (IGF-1R) play important roles in cell proliferation, antiapoptosis, angiogenesis, and metastasis and have been used for targeted therapies for patients with advanced colorectal and lung cancers. However, the expression and function of EGFR and IGF-1R in ampullary adenocarcinoma (AA) have not been examined in detail. We examined the expression of EGFR and IGF-1R in 106 AA patients at our institution using tissue microarrays and immunohistochemistry. The results were correlated with the clinicopathological parameters and survival. Overexpression of EGFR and IGF-1R was detected in 18 (17%) and 26 (25%) of AAs, respectively. Patients with EGFR-high tumors had shorter overall survival (mean, 109.8 ± 22.3 months) than those patients whose tumors were EGFR-low in overall study population (mean, 164.2 ± 10.6 months; P = .04). Overexpression of EGFR correlated with poor overall survival in patients with intestinal-type AA (P = .01) but not in those with pancreaticobiliary-type AAs (P = .47). In multivariate analysis, EGFR overexpression was an independent prognostic factor for overall survival (P = .02). In addition, we found that overexpression of IGF-1R correlated with AAs of pancreaticobiliary histology. No additional correlation between the expression of EGFR or IGF-1R and other clinicopathological factors was observed in our patient population. Our study demonstrates that EGFR and IGF-1R appear to be overexpressed in a subset of AAs and that strong membranous expression of EGFR is an independent predictor for overall survival in patients with AA. EGFR and IGF-1R represent potential therapeutic targets for treatment of patient with AAs.

Biomarkers as predictors of recurrence following curative resection for pancreatic ductal adenocarcinoma: a review

Pancreatic ductal adenocarcinoma (PDA) is the fourth most common cancer causing death in the United States. Early tumor recurrence is an important contributor to the dismal prognosis. The availability of an accurate prognostic biomarker for predicting disease recurrence following curative resection will be beneficial for patient care. Most of the currently studied biomarkers remain in the investigational phase, with CA 19-9 being the only biomarker currently approved by the FDA. Herein, we review the utility of CA 19-9 and other investigational cellular, gene, and molecular tumor markers for predicting PDA recurrence following curative surgical resection.

Effect of treatment with elemene on expression of apoptosis-related proteins in pancreatic carcinoma xenografts in nude mice

AIM: To investigate the expression of PTEN, p53 and Bcl-2 proteins in pancreatic carcinoma xenografts in nude mice after treatment with elemene, and to explore the effect of elemene on the apoptosis of pancreatic cancer cells.

METHODS: Thirty mice with subcutaneous xenografts of a pancreatic cancer cell line (SW1990) were randomly divided into five groups: a negative control group, low- and high-dose elemene-treated groups, a gemcitabine-treated group, and an elemene plus gemcitabine group. Western blot and immunohistochemical staining were used to determine the expression of PTEN, p53 and Bcl-2 proteins in pancreatic carcinoma xenografts in nude mice after treatment with elemene.

RESULTS: The expression of PTEN and p53 proteins had a trend of up-regulation, while the expression of Bcl-2 protein had a trend of down-regulation in pancreatic carcinoma xenografts in nude mice after treatment with elemene. The results of immunohistochemical staining showed the same trend. Compared with the negative control group, the expression of p53 was significantly up-regulated, while Bcl-2 was down-regulated in the high-dose elemene group. Compared with the gemcitabine-treated group, the expression of p53 was significantly up-regulated, but Bcl-2 had no significant change in the combination treatment group. Immunohistochemical staining showed similar results to Western blot analysis.

CONCLUSION: Elemene can up-regulate the expression of PTEN and p53 proteins and down-regulate the expression of Bcl-2 protein in pancreatic cancer in a dose dependent manner, thereby inducing the apoptosis of pancreatic cancer cells.

Decreased RGS6 expression is associated with poor prognosis in pancreatic cancer patients

Regulator of G-protein signaling 6 (RGS6), a member of a family of RGS proteins, has been reported to involve in multiple processes during tumor development. However, its role in pancreatic cancer has not been studied yet. In this study, we aimed to investigate the expression of RGS6 in pancreatic cancer and its role in predicting outcomes of patients with pancreatic cancer. We first measured the expression of RGS6 mRNA in 20 cases of tumor tissues and matched adjacent non-tumorous tissues by quantitative real-time PCR and examined RGS6 protein by immunohistochemistry in tissue microarrays containing 90 tumor and 90 paired adjacent non-tumor tissues. Decreased RGS6 mRNA detected in primary tumor, compared with their non-tumor counterparts. In addition, decreased RGS6 protein expression was associated with tumor differentiation (P = 0.027), pT classification (P = 0.034), smoking status (P = 0.041) and a poor survival (P = 0.007). Cox proportional hazards regression modeling analysis revealed that lymph node metastasis (P = 0.001; hazard ratio, 2.347, 95% CI, 1.387-3.972), tumor differentiation (P = 0.015; hazard ratio, 0.505, 95% CI, 0.291-0.876) and RGS6 expression (P = 0.048; hazard ratio, 0.567, 95% CI, 0.324-0.994) were three independent prognostic factors. Taken together, these date demonstrate that RGS6 decreases in tumor tissue and may serve as a novel biomarker for outcomes in pancreatic cancer patients and be a potential therapeutic target potential therapeutic target.

Aberrant expression of p53, p21, cyclin D1, and Bcl2 and their clinicopathological correlation in ampullary adenocarcinoma

Previous studies on the molecular alterations in ampullary adenocarcinoma (AA) are limited, and little is known about their clinical implications. The objective of this study is to examine the expression of p53, p21, cyclin D1, and Bcl2 and their clinical significance in patients with AA. Tissue microarrays were constructed using archival tissue from 92 patients with AA who underwent pancreaticoduodenectomy at our institution. Each tumor was sampled in triplicate with a 1.0-mm punch from representative areas. The expression of p53, p21, cyclin D1, and Bcl2 was evaluated by immunohistochemistry, and the staining results were correlated with clinicopathological features and survival. Among 92 cases studied, overexpression of p53, p21, cyclin D1, and Bcl2 was observed in 58.7%, 39.2%, 71.7%, and 5.4% of tumors, respectively. Patients whose tumor showed high level of cyclin D1 expression had higher risk of disease recurrence (P = .02) and worse recurrence-free and overall survivals after pancreaticoduodenectomy than did those with no or low cyclin D1 expression (P = .027 and P = .02, respectively). In multivariate analysis, cyclin D1 expression was an independent prognostic factor for both recurrence-free and overall survival (P < .05). However, there was no significant correlation between p53, p21, or Bcl2 expression and survival (P > .05). Our study showed that p53, p21, and cyclin D1, but not Bcl2, are frequently overexpressed in AAs. Cyclin D1 overexpression is associated with increased risk of disease recurrence and worse survival in patients with AA after resection.