Pharmaceutical Agents as Potential Drivers in the Development of Early-Onset Colorectal Cancer: Case-Control Study

BACKGROUND

The incidence of early-onset colorectal cancer (EOCRC) rose abruptly in the mid 1990s, is continuing to increase, and has now been noted in many countries. By 2030, 25% of American patients diagnosed with rectal cancer will be 49 years or younger. The large majority of EOCRC cases are not found in patients with germline cancer susceptibility mutations (eg, Lynch syndrome) or inflammatory bowel disease. Thus, environmental or lifestyle factors are suspected drivers. Obesity, sedentary lifestyle, diabetes mellitus, smoking, alcohol, or antibiotics affecting the gut microbiome have been proposed. However, these factors, which have been present since the 1950s, have not yet been conclusively linked to the abrupt increase in EOCRC. The sharp increase suggests the introduction of a new risk factor for young people. We hypothesized that the driver may be an off-target effect of a pharmaceutical agent (ie, one requiring regulatory approval before its use in the general population or an off-label use of a previously approved agent) in a genetically susceptible subgroup of young adults. If a pharmaceutical agent is an EOCRC driving factor, regulatory risk mitigation strategies could be used.

OBJECTIVE

We aimed to evaluate the possibility that pharmaceutical agents serve as risk factors for EOCRC.

METHODS

We conducted a case-control study. Data including demographics, comorbidities, and complete medication dispensing history were obtained from the electronic medical records database of Maccabi Healthcare Services, a state-mandated health provider covering 26% of the Israeli population. The participants included 941 patients with EOCRC (≤50 years of age) diagnosed during 2001-2019 who were density matched at a ratio of 1:10 with 9410 control patients. Patients with inflammatory bowel disease and those with a known inherited cancer susceptibility syndrome were excluded. An advanced machine learning algorithm based on gradient boosted decision trees coupled with Bayesian model optimization and repeated data sampling was used to sort through the very high-dimensional drug dispensing data to identify specific medication groups that were consistently linked with EOCRC while allowing for synergistic or antagonistic interactions between medications. Odds ratios for the identified medication classes were obtained from a conditional logistic regression model.

RESULTS

Out of more than 800 medication classes, we identified several classes that were consistently associated with EOCRC risk across independently trained models. Interactions between medication groups did not seem to substantially affect the risk. In our analysis, drug groups that were consistently positively associated with EOCRC included beta blockers and valerian (Valeriana officinalis). Antibiotics were not consistently associated with EOCRC risk.

CONCLUSIONS

Our analysis suggests that the development of EOCRC may be correlated with prior use of specific medications. Additional analyses should be used to validate the results. The mechanism of action inducing EOCRC by candidate pharmaceutical agents will then need to be determined.

Tumour extracellular vesicles and particles induce liver metabolic dysfunction

Cancer alters the function of multiple organs beyond those targeted by metastasis1,2. Here we show that inflammation, fatty liver and dysregulated metabolism are hallmarks of systemically affected livers in mouse models and in patients with extrahepatic metastasis. We identified tumour-derived extracellular vesicles and particles (EVPs) as crucial mediators of cancer-induced hepatic reprogramming, which could be reversed by reducing tumour EVP secretion via depletion of Rab27a. All EVP subpopulations, exosomes and principally exomeres, could dysregulate hepatic function. The fatty acid cargo of tumour EVPs-particularly palmitic acid-induced secretion of tumour necrosis factor (TNF) by Kupffer cells, generating a pro-inflammatory microenvironment, suppressing fatty acid metabolism and oxidative phosphorylation, and promoting fatty liver formation. Notably, Kupffer cell ablation or TNF blockade markedly decreased tumour-induced fatty liver generation. Tumour implantation or pre-treatment with tumour EVPs diminished cytochrome P450 gene expression and attenuated drug metabolism in a TNF-dependent manner. We also observed fatty liver and decreased cytochrome P450 expression at diagnosis in tumour-free livers of patients with pancreatic cancer who later developed extrahepatic metastasis, highlighting the clinical relevance of our findings. Notably, tumour EVP education enhanced side effects of chemotherapy, including bone marrow suppression and cardiotoxicity, suggesting that metabolic reprogramming of the liver by tumour-derived EVPs may limit chemotherapy tolerance in patients with cancer. Our results reveal how tumour-derived EVPs dysregulate hepatic function and their targetable potential, alongside TNF inhibition, for preventing fatty liver formation and enhancing the efficacy of chemotherapy.

Abstract PR012: Perioperative liver biopsy captures features of the liver pre-metastatic niche and predicts metastatic outcome after pancreatic cancer resection

Pancreatic cancer (PC) has a high propensity for liver metastasis (LM), a rapidly lethal event, often seen early after resection of the primary tumor. Mounting pre-clinical evidence implicates the establishment of microenvironmental alterations in the liver or other target organs prior to emergence of clinically evident metastases, termed “pre-metastatic niches”, which is a crucial first step in metastatic progression. To determine the translational relevance of these findings, we evaluated liver biopsies from PC patients obtained during pancreatectomy to characterize the cellular, molecular and metabolic features that define the pre-metastatic niche and that may, in turn, be used as biomarkers to stratify the metastatic risk, and as therapeutic targets to interrupt the metastatic cascade. Thus, liver biopsies from 49 patients with localized PC were analyzed by transcriptomics, metabolomics, histopathology, flow cytometry, and in selected patients by single cell RNA sequencing. Patients underwent routine surveillance in a prospective manner to determine which patients developed early (<6 months) or late (>6 months) LM, extrahepatic metastasis, or remained disease-free. Eighteen patients with non-cancerous pancreatic lesions undergoing pancreatectomy were used as controls (non-PC). Single cell transcriptomics analyses and immuno-profiling revealed that, in contrast to non-PC livers, tumor-free, pre-metastatic livers from PC patients exhibited enhanced inflammation evidenced by enrichment of neutrophils, CD11B+ cells, and CD3+ T cells, as well as expansion and activation of a CD11B+ subset of NK cells. Furthermore, immune and metabolic profiling of PC pre-metastatic livers identified features that predicted future patterns of metastasis: high Ki67 proliferation index, neutrophil extracellular trap (NET) formation, and upregulated sortilin-1 gene expression, all of which correlated with earlier LM. Conversely, widespread lobular inflammation, with abundant lobular CD3+ T cells, as well as intact creatine metabolism and steatosis associated with no recurrence, isolated extrahepatic recurrence or later LM. We combined the above variables to develop a decision tree-based prediction model, which performed best for identification of early LM (AUC 0.85). Taken together, these data demonstrate that in patients with apparently localized PC, pre-treatment liver biopsies may confirm the presence of human hepatic pre-metastatic niche and reveal features that correlate with timing and patterns of recurrence (early or late LM, extrahepatic, or no recurrence), after resection of PC. These liver profiles represent novel biomarkers that may be used to provide prognostic information and guide subsequent treatment of PC.

Citation Format: Linda Bojmar, Constantinos P. Zambirinis, Jonathan Hernandez, Jayasree Chakraborty, Samer Hanna, Diane Simeone, David Kelsen, Haiying Zhang, Irina R Matei, Per Sandström, Robert Schwartz, William R. Jarnagin, David Lyden. Perioperative liver biopsy captures features of the liver pre-metastatic niche and predicts metastatic outcome after pancreatic cancer resection [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr PR012.

Abstract C028: The lung pro-thrombotic niche drives cancer-associated thromboembolism and metastasis via extracellular vesicle ITGB2

Thromboembolism (TE) is a common complication in cancer patients and the second leading cause of cancer-related deaths. The incidence of TE varies in different cancer types, with the highest risk in pancreatic ductal adenocarcinoma (PDAC) and in advanced-stage and metastatic cancers. Despite the benefits associated with anti-coagulant therapy for symptomatic TE, the prevention of TE still remains an unmet clinical need due to lack of biomarkers predictive of TE risk and the bleeding risk associated with the routine use of anti-coagulants. Small extracellular vesicles (sEV) mediate cell-to-cell communication. Cancer cells and the tumor microenvironment release large numbers of sEV into the blood circulation and sEVs have displayed a therapeutic and predictive value in systemic diseases. However, the role of sEVs in cancer-associated TE remains to be investigated. Here we show that sEVs from (pre)metastatic lungs of mice with melanoma, breast, lung, and PDAC induce TE in mice and express high levels of integrin beta 2 (ITGB2), while sEVs from tumor cell lines, primary tumors, or other metastasis-bearing organs did not show any pro-thrombotic properties. A specific subtype of interstitial macrophages infiltrating (pre-)metastatic lungs were the main source of ITGB2+ pro-thrombotic sEVs. Blockade of ITGB2 on lung-derived sEVs, or systemically in mice, prevented EV-induced platelet aggregation and TE, and reduced metastasis. Examination of the mechanisms of ITGB2-induced TE showed that EV-associated ITGB2 interacts directly or through fibrin with different binding partners on platelets, and induce their activation and aggregation. Importantly, we found that levels of ITGB2 on sEVs are elevated in the plasma of PDAC patients prior (<30 days) to TE events in comparison to PDAC patients with no history of TE, and thus might serve as prognostic biomarker of TE. Together, our results provide the first evidence of the establishment of a pro-thrombotic lung niche in PDAC as well as other cancer types. Moreover, we identify EV-associated ITGB2 as a new target for the prevention and/or treatment of TE, as well as a potential “liquid biopsy” analyte for the early stratification of patients at high risk of TE.

Citation Format: Serena Lucotti, Yusuke Ogitani, Candia M. Kenific, Linda Bojmar, Michele Cioffi, Pernille Lauritzen, Henrik Molina, Soeren Heissel, Henry B. Lengel, Xiaohong Jing, Haiying Zhang, Irina Matei, Eileen M. O'Reilly, William R. Jarnagin, David Jones, James B. Bussel, David Kelsen, Jacqueline F. Bromberg, Diane M. Simeone, David Lyden. The lung pro-thrombotic niche drives cancer-associated thromboembolism and metastasis via extracellular vesicle ITGB2 [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr C028.

BRCA mutational status shapes the stromal microenvironment of pancreatic cancer linking clusterin expression in cancer associated fibroblasts with HSF1 signaling

Tumors initiate by mutations in cancer cells, and progress through interactions of the cancer cells with non-malignant cells of the tumor microenvironment. Major players in the tumor microenvironment are cancer-associated fibroblasts (CAFs), which support tumor malignancy, and comprise up to 90% of the tumor mass in pancreatic cancer. CAFs are transcriptionally rewired by cancer cells. Whether this rewiring is differentially affected by different mutations in cancer cells is largely unknown. Here we address this question by dissecting the stromal landscape of BRCA-mutated and BRCA Wild-type pancreatic ductal adenocarcinoma. We comprehensively analyze pancreatic cancer samples from 42 patients, revealing different CAF subtype compositions in germline BRCA-mutated vs. BRCA Wild-type tumors. In particular, we detect an increase in a subset of immune-regulatory clusterin-positive CAFs in BRCA-mutated tumors. Using cancer organoids and mouse models we show that this process is mediated through activation of heat-shock factor 1, the transcriptional regulator of clusterin. Our findings unravel a dimension of stromal heterogeneity influenced by germline mutations in cancer cells, with direct implications for clinical research.

Attitudes toward preimplantation genetic testing and quality of life among individuals with hereditary diffuse gastric cancer syndrome

BACKGROUND

Hereditary Diffuse Gastric Cancer (HDGC) syndrome is an autosomal dominant hereditary cancer predisposition associated with germline pathogenic/likely pathogenic variants in the CDH1 gene. Identifying early stage HDGC is difficult, and prophylactic measures can be effective in preventing incidence. Preimplantation Genetic Testing (PGT) can provide information about CDH1 variant status, HDGC risk, and limit familial transmission of CDH1 variants. To date, however, little is known about the attitudes of individuals with CDH1 variants towards PGT.

METHODS

Given that little is known about the reproductive attitudes of individuals with HDGC, we recruited participants with CDH1 variants from a familial gastric cancer registry and administered a cross-sectional survey with open- and closed-ended response items. We assessed attitudes regarding PGT and the effect of HDGC on quality of life.

RESULTS

Participants (n = 21) were predominantly partnered (61.9%), had a personal cancer history (71.4%), and had biological children (71.4%). Interest in learning about PGT was high; 66.7% of participants were interested in PGT and 90.5% approved of healthcare providers discussing PGT with individuals with CDH1 variants. Attitudes regarding personal use were varied. Among all participants, 35% would not, 25% were uncertain, and 40% would use PGT. Personal philosophy and preferences for family and reproduction were key factors related to PGT attitudes. HDGC had moderate effects on participants' quality of life, including social relationships, health behaviors, and emotional experiences including worry about cancer risk and guilt regarding familial implications.

CONCLUSION

PGT was identified by participants as acceptable for use in a variety of contexts and benefits of reproductive counseling involving PGT may extend beyond CDH1 carriers to family members' reproductive behaviors. Dispositions towards PGT are governed by personal philosophy or belief systems. These findings can help guide providers counseling individuals with CDH1 variants.

Abstract 3138: The lung pro-thrombotic niche drives cancer-associated thromboembolism via exosomal ITGB2

Thromboembolism (TE) is a common complication in cancer patients and the second leading cause of cancer-related deaths. The incidence of TE varies in different cancer types, with the highest risk in lung cancer and pancreatic ductal adenocarcinoma (PDAC), and in advanced-stage and metastatic cancers. Despite the benefits associated with thromboprophylaxis for symptomatic TE, the prevention of TE still remains an unmet clinical need due to lack of biomarkers predictive of TE risk and the bleeding risk associated with the routine use of anti-coagulants. Exosomes are small circulating extracellular vesicles that mediate cell-to-cell communication. Cancer cells and the tumor microenvironment release large numbers of exosomes into the blood circulation and have displayed a therapeutic and predictive value in systemic diseases. Integrins expressed on the surface of exosomes drive their selective organotropism and prepare distant sites for metastatic seeding by establishing favorable pre-metastatic niches. Here we show that exosomes from metastasis-bearing lungs or pre-metastatic lungs of mice with melanoma, breast, lung and pancreatic cancer induce TE in mice and express high levels of integrin beta 2 (ITGB2). Instead, exosomes from tumor cell lines, primary tumors or other metastasis-bearing organs did not show any pro-thrombotic properties. Myeloid cells including monocytes/macrophages and neutrophils infiltrating pre- and post-metastatic lungs were the main source of ITGB2+ pro-thrombotic exosomes. Blockade of ITGB2 on lung-derived exosomes, or systemically in mice, prevented exosome-induced platelet aggregation and TE, and reduced metastasis. Examination of the mechanisms of ITGB2-induced TE showed that exosomal ITGB2 interact directly or through fibrin with different binding partners on platelets, and induce their activation and aggregation. Importantly, we found that exosomal ITGB2 levels are elevated in the plasma of PDAC patients prior to TE events in comparison to PDAC patients with no history of TE, and thus might serve as prognostic biomarker of TE. Together, our results provide the first evidence of the establishment of a pro-thrombotic lung niche in different cancer types. Moreover, we identify exosomal ITGB2 as a new target for the prevention and/or treatment of TE, as well as a potential “liquid biopsy” analyte for the early stratification of patients at high risk of TE.

Citation Format: Serena Lucotti, Yusuke Ogitani, Candia M. Kenific, Linda Bojmar, Michele Cioffi, Pernille Lauritzen, Henrik Molina, Soren Heissel, Harry B. Lengel, Xiaohong Jing, Haiying Zhang, Irina Matei, Eileen M. O'Reilly, William R. Jarnagin, David R. Jones, James B. Bussel, David Kelsen, Jacqueline F. Bromberg, Diane M. Simeone, David Lyden. The lung pro-thrombotic niche drives cancer-associated thromboembolism via exosomal ITGB2 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3138.

Different hotspot p53 mutants exert distinct phenotypes and predict outcome of colorectal cancer patients

The TP53 gene is mutated in approximately 60% of all colorectal cancer (CRC) cases. Over 20% of all TP53-mutated CRC tumors carry missense mutations at position R175 or R273. Here we report that CRC tumors harboring R273 mutations are more prone to progress to metastatic disease, with decreased survival, than those with R175 mutations. We identify a distinct transcriptional signature orchestrated by p53R273H, implicating activation of oncogenic signaling pathways and predicting worse outcome. These features are shared also with the hotspot mutants p53R248Q and p53R248W. p53R273H selectively promotes rapid CRC cell spreading, migration, invasion and metastasis. The transcriptional output of p53R273H is associated with preferential binding to regulatory elements of R273 signature genes. Thus, different TP53 missense mutations contribute differently to cancer progression. Elucidation of the differential impact of distinct TP53 mutations on disease features may make TP53 mutational information more actionable, holding potential for better precision-based medicine.

Abstract LB204: HSF1 promotes inflammation induced tumor development through ECM remodeling

HSF1 promotes inflammation induced tumor development through ECM remodelingAbstractIn the colon, long-term exposure to chronic inflammation drives colitis associated colon cancer (CAC) in patients with inflammatory bowel disease (IBD). Chronic inflammation underlies tumor initiation, promotion, invasion, and metastasis. While the causal and clinical link between chronic inflammation and CAC is well established, we lack a molecular understanding of what is the way in which chronic inflammation leads to develop colon cancer. Within the tumor, cancer cells are surrounded by a variety of non-malignant cells, such as macrophages, endothelial cells, neutrophils, cancer-associated fibroblasts (CAFs), and together with the extracellular matrix (ECM) they compose the tumor microenvironment (TME), also termed the stroma. Even the most aggressive cancers depend and interact with their environment mostly through secreted factors. Unlike cancer cells, stromal cells are genomically stable, and do not harbor oncogenic mutations that could drive their co-evolution and functional reprogramming. Rather, stromal reprogramming is thought to be achieved by transcriptional rewiring. Previous work by us and others has shown that the master regulator heat shock factor 1 (HSF1) plays a crucial role in this process, by mediating a transcriptional program in fibroblasts that enables their reprogramming into cancer-associated fibroblasts (CAFs) to promote malignancy. We hypothesizde that HSF1 plays a crucial role in inflammation-driven cancer by initiation of a transcriptional program that leads to changes in the extracellular matrix (ECM). We found that, in cell culture, cancer-induced ECM assembly by fibroblasts requires HSF1. Using an inflammation-driven cancer model in mice, we measured the changes in proteomic and ECM organization over time. We found that HSF1 drives a transcriptional program that leads to ECM remodeling in early stages and results in development of colon cancer. Loss of HSF1 prevents inflammation-induced ECM remodeling. Further to that, in CAC patients, we found high activation of stromal HSF1 and similarity to our HSF1 proteomic ECM signature in human colorectal cancer driven by HSF1. Thus, HSF1-dependent ECM remodeling mediates the transition from chronic inflammation to colon cancer.

Citation Format: Oshrat Levi Galibov, Hagar Lavon, Rina Wassermann-Dozorets, Meirav Pevsner-Fischer, Shimrit Mayer, Esther Wershof, Yaniv Stein, Lauren E. Brown, Wenhan Zhang, Gil Friedman, Reinat Nevo, Ofra Golani, Lior H. Katz, Rona Yaeger, Ido Laish, John A. Porco, Erik Sahai, Dror S Shouval, David Kelsen, Ruth Scherz-Shouval. HSF1 promotes inflammation induced tumor development through ECM remodeling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB204.

Artificial Intelligence and Early Detection of Pancreatic Cancer: 2020 Summative Review

ABSTRACT

Despite considerable research efforts, pancreatic cancer is associated with a dire prognosis and a 5-year survival rate of only 10%. Early symptoms of the disease are mostly nonspecific. The premise of improved survival through early detection is that more individuals will benefit from potentially curative treatment. Artificial intelligence (AI) methodology has emerged as a successful tool for risk stratification and identification in general health care. In response to the maturity of AI, Kenner Family Research Fund conducted the 2020 AI and Early Detection of Pancreatic Cancer Virtual Summit (www.pdac-virtualsummit.org) in conjunction with the American Pancreatic Association, with a focus on the potential of AI to advance early detection efforts in this disease. This comprehensive presummit article was prepared based on information provided by each of the interdisciplinary participants on one of the 5 following topics: Progress, Problems, and Prospects for Early Detection; AI and Machine Learning; AI and Pancreatic Cancer-Current Efforts; Collaborative Opportunities; and Moving Forward-Reflections from Government, Industry, and Advocacy. The outcome from the robust Summit conversations, to be presented in a future white paper, indicate that significant progress must be the result of strategic collaboration among investigators and institutions from multidisciplinary backgrounds, supported by committed funders.

Extracellular vesicle and particle isolation from human and murine cell lines, tissues, and bodily fluids

We developed a modified protocol, based on differential ultracentrifugation (dUC), to isolate extracellular vesicles and particles (specifically exomeres) (EVPs) from various human and murine sources, including cell lines, surgically resected tumors and adjacent tissues, and bodily fluids, such as blood, lymphatic fluid, and bile. The diversity of these samples requires robust and highly reproducible protocols and refined isolation technology, such as asymmetric-flow field-flow fractionation (AF4). Our isolation protocol allows for preparation of EVPs for various downstream applications, including proteomic profiling.

For complete details on the use and execution of this protocol, please refer to Hoshino et al. (2020).

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EVP isolation from human cell lines, tissues, and bodily fluids

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First protocol describing EVP isolation from human tumor tissues and matched adjacent tissues

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Improved EVP isolation and total EVP protein yield by dissecting tissues into pieces

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AF4 fractionation to further analyze EVP samples

Cell-free DNA (cfDNA) and Exosome Profiling from a Year-Long Human Spaceflight Reveals Circulating Biomarkers

Liquid biopsies based on cell-free DNA (cfDNA) or exosomes provide a noninvasive approach to monitor human health and disease but have not been utilized for astronauts. Here, we profile cfDNA characteristics, including fragment size, cellular deconvolution, and nucleosome positioning, in an astronaut during a year-long mission on the International Space Station, compared to his identical twin on Earth and healthy donors. We observed a significant increase in the proportion of cell-free mitochondrial DNA (cf-mtDNA) inflight, and analysis of post-flight exosomes in plasma revealed a 30-fold increase in circulating exosomes and patient-specific protein cargo (including brain-derived peptides) after the year-long mission. This longitudinal analysis of astronaut cfDNA during spaceflight and the exosome profiles highlights their utility for astronaut health monitoring, as well as cf-mtDNA levels as a potential biomarker for physiological stress or immune system responses related to microgravity, radiation exposure, and the other unique environmental conditions of spaceflight.

Heat Shock Factor 1-dependent extracellular matrix remodeling mediates the transition from chronic intestinal inflammation to colon cancer

In the colon, long-term exposure to chronic inflammation drives colitis-associated colon cancer (CAC) in patients with inflammatory bowel disease. While the causal and clinical links are well established, molecular understanding of how chronic inflammation leads to the development of colon cancer is lacking. Here we deconstruct the evolving microenvironment of CAC by measuring proteomic changes and extracellular matrix (ECM) organization over time in a mouse model of CAC. We detect early changes in ECM structure and composition, and report a crucial role for the transcriptional regulator heat shock factor 1 (HSF1) in orchestrating these events. Loss of HSF1 abrogates ECM assembly by colon fibroblasts in cell-culture, prevents inflammation-induced ECM remodeling in mice and inhibits progression to CAC. Establishing relevance to human disease, we find high activation of stromal HSF1 in CAC patients, and detect the HSF1-dependent proteomic ECM signature in human colorectal cancer. Thus, HSF1-dependent ECM remodeling plays a crucial role in mediating inflammation-driven colon cancer.

Extracellular Vesicle and Particle Biomarkers Define Multiple Human Cancers

There is an unmet clinical need for improved tissue and liquid biopsy tools for cancer detection. We investigated the proteomic profile of extracellular vesicles and particles (EVPs) in 426 human samples from tissue explants (TEs), plasma, and other bodily fluids. Among traditional exosome markers, CD9, HSPA8, ALIX, and HSP90AB1 represent pan-EVP markers, while ACTB, MSN, and RAP1B are novel pan-EVP markers. To confirm that EVPs are ideal diagnostic tools, we analyzed proteomes of TE- (n = 151) and plasma-derived (n = 120) EVPs. Comparison of TE EVPs identified proteins (e.g., VCAN, TNC, and THBS2) that distinguish tumors from normal tissues with 90% sensitivity/94% specificity. Machine-learning classification of plasma-derived EVP cargo, including immunoglobulins, revealed 95% sensitivity/90% specificity in detecting cancer. Finally, we defined a panel of tumor-type-specific EVP proteins in TEs and plasma, which can classify tumors of unknown primary origin. Thus, EVP proteins can serve as reliable biomarkers for cancer detection and determining cancer type.

Systemic Chemotherapy for Metastatic Colitis-Associated Cancer Has a Worse Outcome Than Sporadic Colorectal Cancer: Matched Case Cohort Analysis

BACKGROUND

Colitis-associated cancers (CAC) are a catastrophic complication of inflammatory bowel disease; at diagnosis, CAC is frequently at an advanced stage. Although the genomic alterations (GA) in CAC are different from sporadic colorectal cancer (CRC), the same systemic therapies are used. We compared clinically relevant outcomes using standard care systemic chemotherapy of stage IV CAC versus a matched patient control cohort of stage IV CRC patients.

PATIENTS AND METHODS

A retrospective matched cohort design was used. Eighteen cases of stage IV CAC (7 ulcerative colitis, 11 Crohn disease) and 18 CRC were identified. GA analysis was available for all patients. Outcome endpoints included response rate and response duration, progression-free survival, and OS.

RESULTS

Although the response rates were similar (CAC 35.7% vs. CRC 57.1%, P = .45), the median duration of response for CAC was significantly shorter (1.4 months, vs. CRC 11.8 months, P = .006). There was no difference in dose density of first-line therapy between cohorts, suggesting that shorter response duration was due to more rapid development of chemotherapy resistance. Median OS was significantly shorter for CAC patients (13 vs. 27.6 months, P = .034). As expected, there was a difference in the spectrum of GA between CAC and CRC cohorts. However, GA associated with poor prognosis (eg, B-Raf) were no more frequent in the CAC cohort.

CONCLUSION

Clinically meaningful outcomes of duration of response and OS are worse for CAC versus sporadic CRC patients treated with FOLFOX or FOLFIRI as first therapy for metastatic disease.

Predictors of overall and recurrence-free survival after neoadjuvant chemotherapy for gastroesophageal adenocarcinoma: Pooled analysis of individual patient data (IPD) from randomized controlled trials (RCTs)

BACKGROUND

Neoadjuvant chemotherapy improves prognosis of patients with locally advanced gastroesophageal adenocarcinoma. The aim of this study was to identify predictors for postoperative survival following neoadjuvant therapy. These could be useful in deciding about postoperative continuation of chemotherapy.

METHODS

This meta-analysis used IPD from RCTs comparing neoadjuvant chemotherapy with surgery alone for gastroesophageal adenocarcinoma. Trials providing IPD on age, sex, performance status, pT/N stage, resection status, overall and recurrence-free survival were included. Survival was calculated in the entire study population and subgroups stratified by supposed predictors and compared using the log-rank test. Multivariable Cox models were used to identify independent survival predictors.

RESULTS

Four RCTs providing IPD from 553 patients fulfilled the inclusion criteria. (y)pT and (y)pN stage and resection status strongly predicted postoperative survival both after neoadjuvant therapy and surgery alone. Patients with R1 resection after neoadjuvant therapy survived longer than those with R1 resection after surgery alone. Patients with stage pN0 after surgery alone had better prognosis than those with ypN0 after neoadjuvant therapy. Patients with stage ypT3/4 after neoadjuvant therapy survived longer than those with stage pT3/4 after surgery alone. Multivariable regression identified resection status and (y)pN stage as predictors of survival in both groups. (y)pT stage predicted survival only after surgery alone.

CONCLUSION

After neoadjuvant therapy for gastroesophageal adenocarcinoma, survival is determined by the same factors as after surgery alone. However, ypT stage is not an independent predictor. These results can facilitate the decision about postoperative continuation of chemotherapy in pretreated patients.

Genomic Alterations Observed in Colitis-Associated Cancers Are Distinct From Those Found in Sporadic Colorectal Cancers and Vary by Type of Inflammatory Bowel Disease

BACKGROUND & AIMS

Patients with inflammatory bowel diseases, such as Crohn's disease (CD) and ulcerative colitis (UC), are at increased risk for small bowel or colorectal cancers (colitis-associated cancers [CACs]). We compared the spectrum of genomic alterations in CACs with those of sporadic colorectal cancers (CRCs) and investigated differences between CACs from patients with CD vs UC.

METHODS

We studied tumor tissues from patients with CACs treated at Memorial Sloan Kettering Cancer Center or Weill Cornell Medical College from 2003 through 2015. We performed hybrid capture-based next-generation sequencing analysis of >300 cancer-related genes to comprehensively characterize genomic alterations.

RESULTS

We performed genomic analyses of 47 CACs (from 29 patients with UC and 18 with CD; 43 primary tumors and 4 metastases). Primary tumors developed in the ileum (n = 2), right colon (n = 18), left colon (n = 6), and rectosigmoid or rectum (n = 21). We found genomic alterations in TP53, IDH1, and MYC to be significantly more frequent, and mutations in APC to be significantly less frequent, than those reported in sporadic CRCs by The Cancer Genome Atlas or Foundation Medicine. We identified genomic alterations that might be targeted by a therapeutic agent in 17 of 47 (36%) CACs. These included the mutation encoding IDH1 R132; amplification of FGFR1, FGFR2, and ERBB2; and mutations encoding BRAF V600E and an EML4-ALK fusion protein. Alterations in IDH1 and APC were significantly more common in CACs from patients with CD than UC.

CONCLUSIONS

In an analysis of CACs from 47 patients, we found significant differences in the spectrum of genomic alterations in CACs compared with sporadic CRCs. We observed a high frequency of IDH1 R132 mutations in patients with CD but not UC, as well as a high frequency of MYC amplification in CACs. Many genetic alterations observed in CACs could serve as therapeutic targets.

Longitudinal Quality-of-Life Analysis of RTOG 94-05 (Int 0123):A Phase III Trial of Definitive Chemoradiotherapy for Esophageal Cancer

BACKGROUND

Longitudinal quality of life (QoL) was compared for patients with esophageal cancer receiving definitive chemoradiotherapy (CRT) with conventional-dose (CD) vs. high-dose (HD) radiotherapy as used in the RTOG phase III 94-05 trial (Intergroup 0123).

METHODS

Between June 12, 1995, and July 1, 1999, 236 patients with cT1-4NxM0 esophageal cancer were randomized to CD CRT (50.4 Gy and concurrent 5-fluorouracil and cisplatin) vs. HD CRT (64.8 Gy and the same chemotherapy). QoL was assessed using the Functional Assessment of Cancer Therapy, Head & Neck (version 2) at baseline, after CRT, at 8 months from the start of CRT, and at 1 year.

RESULTS

Of 218 eligible patients, 166 participated in pretreatment QoL assessments (82 HD, 84 CD). Patients with ≥10% weight loss and Karnofsky Performance Status 60-80 were less likely to participate (P = .02 and P = .002, respectively). Pretreatment characteristics for participating patients were similar in both arms. At CRT completion, 96 patients completed QoL (46 HD, 50 CD) assessment. Total mean QoL was significantly lower in the HD arm (P = .02) and remained lower at 8 and 12 months after the start of CRT, but these values did not reach statistical significance. Change in mean QoL from baseline to each of the three subsequent assessment time points did not differ significantly between the two treatment arms.

CONCLUSIONS

For patients treated with definitive CRT for esophageal cancer, radiation dose escalation to 64.8 Gy does not significantly improve QoL. These results provide additional evidence that radiotherapy to 50.4 Gy should remain the standard of care.

A phase 2 trial of erlotinib in patients with previously treated squamous cell and adenocarcinoma of the esophagus

BACKGROUND

Tyrosine kinase inhibitors (TKIs) of the epidermal growth factor receptor (EGFR) have activity in solid tumors. The authors evaluated an oral EGFR TKI, erlotinib, in patients with previously treated esophageal cancer.

METHODS

Thirty patients with measurable, metastatic cancer of the esophageal and gastroesophageal junction received 150 mg erlotinib daily. EGFR-negative tumors (6 patients; 20%) and EGFR-over expressing tumors (24 patients; 80%) were treated. Most patients were men (70%) with adenocarcinoma (57%) and had received previous chemotherapy (97%).

RESULTS

Two partial responses were observe d in the EGFR-positive cohort (2 of 24 patients; 8%), and no responses were observed in the EGFR-negative cohort (0 of 6 patients). Reponses were limited to patients who had squamous cell carcinoma (2 of 13 patients; 15%; response duration, 5.5-7 months). The time to tumor progression was longer in patients who had squamous cell carcinoma (3.3 months; range, 1-24 months) compared with patients who had adenocarcinoma (1.6 months; range, 1-6 months; P = .026). Therapy was tolerable with the expected toxicity of skin rash (grade 1-2, 67%; grade 3, 10%).

CONCLUSIONS

Erlotinib had limited activity in patients with esophageal cancer, and responses and some protracted stable disease were observed in those with squamous cell carcinoma. Efficacy according to EGFR status could not be assessed given the rarity of EGFR-negative tumors. The current results indicated that further evaluation of this agent in squamous cell carcinoma is warranted. Cancer 2011. © 2010 American Cancer Society.

Phase II study of bevacizumab in combination with cetuximab plus irinotecan in irinotecan-refractory colorectal cancer (CRC) patients who have progressed on a bevacizumab-containing regimen (The BOND 2.5 Study)

4087

Background: We previously showed that adding bevacizumab (bev) to cetuximab (cetux) plus irinotecan (IRI) in bev-naïve, IRI-refractory CRC patients is feasible, and yielded a favorable response rate and time to tumor progression (TTP) compared with historical controls (Saltz: JCO, 2007). Since most CRC patients now receive a bev-containing regimen prior to cetux, we evaluated the addition of bev to cetux plus IRI (CBI) in patients with metastatic CRC who had previously progressed on chemo + bev. Methods: All patients were naïve to cetux. The importance of KRAS mutation was not appreciated when the trial was designed and this has not yet been evaluated. Patients received IRI at the same dose and schedule as last received prior to study, Cetux 400 mg/m2 loading dose, then weekly at 250 mg/m2, plus Bev 5 mg/kg given every two weeks or 7.5 mg/kg given every three weeks. Results: 33 received treatment. Median age was 58 (range 29–85). Median number of prior regimens was 2 (range 1–2). Median performance status was ECOG 1 (range 0–1). Patients received a median of 2 cycles (range 1–15). Grade 3/4 Toxicities: Acneiform Rash 18%, hypomagnesemia 6%, hypophosphatemia 6%, Neutropenia 15%, Diarrhea 6%. One patient developed neutropenic fever and one patient had a hypersensitivity reaction to cetux. At a median follow up of 32 months (range 21–32 months) in 33 evaluable patients, we observed 3 (9%) partial responses and 11 (33%) patients with stable disease for > 4 months. Median TTP was 3.9 months (95% CI: 1.3 - 6.8). Median survival was 10.6 months (95% CI: 6.6 - 13.8). Conclusions: The toxicity profile was similar to what would have been expected from the individual agents alone. Recognizing the limitations of cross-study comparisons, the response rates and TTP seen with CBI in patients who have previously progressed on bev do not appear to be as encouraging as the 37% response rate and 7.3 months TTP seen in the BOND 2 trial of bev-naïve CRC patients. Ongoing randomized trials, including SWOG 0600, will be needed to definitively determine the contribution of continued use of bev after progression on a bev-containing regimen. Supported by Genentech.

[Table: see text]

Phase II trial of preoperative bevacizumab (Bev), irinotecan (I), cisplatin (C), and radiation (RT) in esophageal adenocarcinoma: Preliminary safety analysis

4573

Background: Preo chemoRT with weekly I/C and 5040 cGy followed by surgery is well tolerated [JCO 24: Abstract 4032; 2006]. ECOG trial E1201recently reported a median survival of 34 months with this preop regimen [JCO 26: Abstract 4532; 2008]. Bev + chemo improves response rate (RR) and time to progression (TTP) when added to weekly I/C in advanced esophagogastric cancer but does not increase chemo toxicity [JCO 24: 5201; 2006]. We are now combining in a Phase II trial Bev/I/C with concurrent radiotherapy (RT) in esophageal adenocarcinoma (EA) with the primary endpoint of safety. Methods: Patients (pts) with resectable Siewert's I or II EA were staged by EUS, PET, and CT. Induction chemo consisted of I-50–65 mg/m2 and C-30 mg/m2 weeks 1,2,4,5, Bev-7.5 mg/kg weeks 1 and 4; and, during RT (180 cGy daily to 5040 cGy), I/C was given weeks 7,8,10,11 and Bev weeks 7,10. Esophagectomy was 6–8 weeks after RT. A planned toxicity analysis was made in 10–15 pts completing chemoRT, and in 10 pts undergoing surgery: toxicity was acceptable if grade 3 / 4 hematologic toxicity remained < 72% and non hematologic toxicity < 40% during combined chemoRT (based on our prior phase II trial of I/C/RT [JCO 24: Abstract 4032; 2006]); and if pts undergoing surgery had no surgical complication related to Bev. Results: 18 pts have been enrolled, 12 male: 6 female; 7 Siewert I: 11 Siewert II; T3N1 12: T3N0 5: T2N0 1. 14 are evaluable for toxicity, 2 are too early, one progressed prior to RT, and one was taken off due to a CVA from a patent foramen ovale. Grade 3/4 neutropenia occurred in 4 pts (29%). Grade 3/4 non heme toxicity occurred in 5 pts (36%), including esophagitis 2 pts (14%), neutropenic fever 1 pt (7%), and pulmonary embolism 1 pt (7%). No grade 3 / 4 hypertension was seen, and 3 pts (21%) developed grade 1 proteinuria. Ten pts underwent surgery, and there were no unexpected surgical or wound complications; there were 2 anastomotic leaks. Pathologic responses: 1 pathologic CR and 1 T0N1. Conclusions: In a preliminary analysis of pts treated with Bev + preop chemoRT in EA, there was no increase in hematologic/non hematologic toxicity or Bev related surgical complications. Accrual will continue to 33 patients. Supported by Genentech.

[Table: see text]

Analysis of survival with modified docetaxel, cisplatin, fluorouracil (mDCF), and bevacizumab (BEV) in patients with metastatic gastroesophageal (GE) adenocarcinoma: Results of a phase II clinical trial

4512

Background: Metastatic GE cancer is an aggressive disease with poor patient (pt) outcomes. Despite response rates of 30–60% to combination chemotherapy, response duration is usually 4–6 mo and 24-mo survival is 5–10%. The addition of BEV to chemotherapy has improved survival in several solid tumors, and has demonstrated encouraging activity in GE cancer (Shah et al, JCO 2006). We report mature tolerability and efficacy results of mDCF+BEV in GE cancer, with an emphasis on prolonged pt survival. Methods: Previously untreated metastatic GE pts with adequate end organ function received BEV 10mg/kg, Docetaxel 40mg/m2, FU 400mg/m2, Leucovorin 400mg/m2 on day 1, FU 1000 mg/m2/day x 2 days IVCI, and Cisplatin 40mg/m2 on day 3. Treatment is repeated every 14 days without prophylactic growth factor support. The primary objective is to improve 6-month progression free survival (PFS) from 43% (historical DCF control) to 63% with the addition of BEV. Target accrual is 44 evaluable pts, with 10% type I & II error. Secondary objectives include tolerability, response rates (RECIST), median PFS, 12-mo survival, and overall survival (OS). Results: Pt enrollment has completed: median age 57(range 29–74), median KPS 80% (70–100), M:F 32:12, gastric/GEJ/esophagus 22:17:5. In 39 patients with measurable disease we observed 26 confirmed partial responses (67%, 95% CI 50%- 81%), and 12 (31%) stable disease. Six-month PFS is 79% (95% CI 68%-93%), the median PFS is 12 mo (95% CI: 8.8–16). At median follow up of 12.3 mo, median OS is 16.2 mo (95%CI 11.4-infinitiy). 12- and 18-mo OS is 63% (95%CI 44–77%) and 46% (95%CI 27–63%), respectively. Minimal chemotherapy related grade 3–4 adverse events were observed: fatigue (20%), dehydration (13%), mucositis (9%), nausea/vomiting (7%), febrile neutropenia (4%). BEV related adverse event was perforation (n=1) and bleeding (n=1). 31% developed grade 3–4 venous thromboembolism, of which 93% were asymptomatic. No grade 3–4 hypertension, proteinuria or arterial thrombosis was observed. Conclusions: mDCF+BEV appears tolerable and has notable long term pt outcomes: 6-mo PFS is 79% (surpassing our efficacy endpoint), median OS 16.2 mo, and 18-mo OS 46%.

No significant financial relationships to disclose.

Randomized phase II trial evaluating two paclitaxel and cisplatin-containing chemoradiation regimens as adjuvant therapy in resected gastric cancer (RTOG-0114)

PURPOSE

The investigational arm of INT0116, a fluorouracil (FU) and leucovorin-containing chemoradiotherapy regimen, is a standard treatment for patients with resected gastric cancer with a 2-year disease-free survival rate (DFS) of 52%. Toxicity is also significant. More beneficial and safer regimens are needed.

PATIENTS AND METHODS

We performed a randomized phase II study among 39 cancer centers to evaluate two paclitaxel and cisplatin-containing regimens, one with FU (PCF) and the other without (PC) in patients with resected gastric cancer. Patients received two cycles of postoperative chemotherapy followed by 45 Gy of radiation with either concurrent FU and paclitaxel or paclitaxel and cisplatin. The primary objective was to show an improvement in 2-year DFS to 67% as compared with INT 0116.

RESULTS

From May 2001 to February 2004 (study closure), 78 patients entered this study, and 73 were evaluable. At the planned interim analysis of 22 patients on PCF, grade 3 or higher GI toxicity was 59%. This was significantly worse than INT0116, and this arm was closed. Accrual continued on PC. The median DFS was 14.6 months for PCF and has not been reached for PC. For PC the 2-year DFS is 52% (95% CI, 36% to 68%).

CONCLUSION

Though PC appears to be safe and the median DFS favorable, the DFS failed to exceed the lower bound of 52.9% for the targeted 67% DFS at 2 years and can not be recommended as the adjuvant arm for future randomized trials.

A phase 1 dose-escalation study of irinotecan in combination with 17-allylamino-17-demethoxygeldanamycin in patients with solid tumors

PURPOSE

Both heat shock protein 90 (Hsp90) and checkpoint kinase 1 (Chk1) have emerged as novel therapeutic targets. We conducted a phase I study of irinotecan and the Hsp90 inhibitor 17AAG, which can also down-regulate Chk1, in patients with solid tumors.

EXPERIMENTAL DESIGN

During the dose escalation phase, patients received i.v. irinotecan followed by 17AAG once weekly for 2 weeks in a 21-day cycle. At the maximum tolerated dose (MTD), additional patients were enrolled to undergo pre- and post-17AAG tumor biopsies for pharmacodynamic evaluation. The pharmacokinetics of irinotecan, 17AAG, and their metabolites were characterized. Tumor p53 status as determined by immunohistochemistry was correlated with antitumor activity.

RESULTS

Twenty-seven patients with a variety of solid tumors were enrolled. Four patients developed dose-limiting toxicity at dose level 4 (100 mg/m(2) irinotecan and 375 mg/m(2) 17AAG) including nausea, vomiting, diarrhea, and pulmonary embolism. The pharmacokinetics of 17AAG and its metabolite were not significantly affected by the coadministration of irinotecan, and vice versa. There was no partial response, although tumor shrinkage was observed in six patients. Five of 10 patients with p53-mutant tumor had stable disease as the best response compared with 2 of 6 patients with p53-wildtype tumor (P = 0.63). Evidence for Hsp90 inhibition by 17AAG, resulting in phospho-Chk1 loss, abrogation of the G(2)-M cell cycle checkpoint, and cell death could be shown in tumor biopsy samples obtained at the MTD.

CONCLUSIONS

The combination of irinotecan and 17AAG can be given to patients with acceptable toxicity. The recommended phase II dose of the combination is 100 mg/m(2) irinotecan and 300 mg/m(2) 17AAG.

Small cell carcinoma of the esophagus: Review of the Memorial Sloan-Kettering Cancer Center (MSKCC) experience

4631

Background: Esophageal small cell carcinoma (ESC) is rare and accounts for <1% of all esophageal cancers. It is treated like pulmonary SC but the optimal approach of surgery, chemotherapy or radiotherapy is unknown. Prior series (Chest 107:179, Cancer 88:262) indicate a poor median overall survival (OS) of 7–12 months (mos), rare long-term (LT) survival and the need for surgery as part of curative therapy. Methods: We reviewed records of patients (pts) with ESC treated from 1980 to 2005. All pathology was reviewed at MSKCC. Results: 24 pts were identified, with records available for 21. 86% male, 14% female, median age 60, 67% smokers. 81% had pure SC histology, with 85% of tumors in the lower esophagus or gastroesophageal junction. 13/21 (62%) had limited disease (LD) by VALSG criteria. For extensive disease (ED), liver (63%) was most common metastatic site (mets). Treatment for LD was: chemotherapy (chemo) only (3 pts, 23%), surgery only (1 pt, 8%), surgery and adjuvant chemo (3 pts) and chemoradiation (CRT) without surgery (6 pts, 46%). The most common chemo given was cisplatin/carboplatin and etoposide (81%). Pts with ED received chemo alone. Overall median survival was 19.8 mos (range, 1.5 mos to 11.2+ years (yrs)); for LD Pts, 22.3 mos (range, 6 mos to 11.2+ yrs); for ED Pts, 10.9 mos (range, 1.5 mos to 2.2 yrs). At median follow-up of 32 mos, 5 pts are alive (4 without disease (NED) and 1 with disease); 2 pts are alive >5 yrs. 4 originally had LD and 3 of 4 received CRT only without surgery. None received whole brain radiation (WBXRT). 1 LD pt treated with surgery and adjuvant chemo recurred after 4 yrs, was salvaged with CRT and is NED 11.2 yrs after diagnosis. Of 18 pts with progression, 10 (56%) had new mets. Most common site was liver (4 pts) and only 1 pt had brain mets. Of 6 pts with LD who received CRT only, 3 recurred (1 local and 2 distant). Of 4 pts with LD who underwent surgery, all recurred (1 local, 3 distant). Conclusions: Pts with ESC with LD who received CRT without surgery can have LT survival. The role of surgery remains unclear. LT survival for 1 pt who underwent salvage CRT for recurrence after surgery argues for aggressive therapy for recurrence. Unlike pulmonary SC, brain mets are uncommon and WBXRT may not be needed for LT survival.

No significant financial relationships to disclose.

Volumetric 3D CT analysis - an early predictor of response to therapy

4576

Background: Evidence suggests that changes in unidimensional measurements (using RECIST criteria) may not accurately reflect actual changes in tumor size, and do not correlate well with other biomarkers of response, tumor progression, or patient outcome. We evaluated changes in tumor volume of target lesions with volumetric CT, and compared them with response assessments derived from RECIST criteria. Methods: We evaluated target lesions, including lymph node, liver, peritoneal and lung metastases in 25 patients with metastatic gastric cancer or gastroespohageal junction adenocarcinoma treated on a phase II clinical trial with irinotecan, cisplatin and bevacizumab. All patients underwent thin-section multidetector CT at baseline and 6-week follow-up for 10 cycles. Target lesions were measured unidimensionally and volumetrically, using validated automated and semiautomated segmentation algorithms. For initial analysis, correlation was made with the RECIST response using a cut-off value of 65% volume change. A ratio of change in RECIST measure to volume measure was calculated at time of maximal clinical response for each patient, as well as for responders versus non-responders. Results: 18 of 25 (72%) patients showed a clinical response. Of these 18 responders, 5, 6, 4, and 3 were identified as responders using RECIST criteria after cycles 1, 2, 3, and 4, respectively. Using a cut-off of 65% volume change, 14 of these responders were indentified after cycle 1, and 4 were identified after cycle 2. Using a cut-off value of 65%, volume measurements identified responders a mean of 50.3 days earlier than did RECIST criteria. There was a statistically significant (p<0.01) change in ratio of volume measurement change to RECIST measurement change for responding versus stable patients. Conclusions: Volumetric change in tumor size appears to predict clinical response earlier than do RECIST criteria in the majority of cases. Changes in volume are more sensitive because they exhibit a wider dynamic range. Ratios of size changes volumetrically appears to better discriminate RECIST responders from those with stable disease. Further work is needed to define the biologically relevant cut-off value for volume change, and to correlate volume change with other biomarkers.

No significant financial relationships to disclose.

Evaluation of the feasibility of expression microarray analysis in endoscopically obtained biopsies of gastric carcinoma and their clinical applicability

21164

Background: The feasibility of extracting high quality RNA for expression microarray analysis from endoscopic biopsy in gastric carcinoma has not been previously established. Methods: Patients with histologically confirmed locally advanced gastric or gastroesophageal junction adenocarcinoma were screened for enrollment in an NCI-sponsored trial of neoadjuvant irinotecan and cisplatin chemotherapy (NC1–5917). All patients underwent a repeat endoscopic biopsy for the procurement of fresh tumor tissue. Gross microdissection was performed to enrich the sample to at least 80% malignancy. RNA was isolated from the tumor specimens using RNeasy columns (Qiagen) and its quality verified by RNA 6000 NanoAssay and Bioanalyzer 2100 (Agilent). Gene expression profiling was performed on Human Genome U133A GeneChip (Affymetrix) which contained 22,215 oligonucleotide-base probe-sets. Differential gene expression profiles for Lauren's classification were assessed using empirical Bayes t test, a threshold p < 0.001 was considered statistically significant. Results: Of 36 patients with previous biopsy confirmed gastric cancer, repeat endoscopic biopsy identified carcinoma in 28 patients (78%, 95%CI 61–90%). Adequate RNA for microarray analysis was obtained from 21 patients-representing 58% of those who presented for the procedure and 75% in whom endoscopic biopsies confirmed malignancy. This yield improved with increasing number of samples taken. Lauren's classification was available on 26 patients who underwent resection. From the total 54,613 gene probe-sets on the arrays, comparison of the expression profiles of diffuse-type and intestinal-type identified 167 genes that were differentially expressed. Diffuse gastric cancer demonstrated altered expression of genes related to cell-matrix interaction whereas intestinal gastric cancer expression analysis showed enhancement of cell growth. Conclusions: Endoscopic biopsy for expression analysis of gastric cancer is feasible with increasing yield with each core taken. Expression analysis at the time of endoscopic biopsy can differentiate Lauren's histology, a characteristic not routinely evaluable by pathologic review.

No significant financial relationships to disclose.

Combined modality chemoradiation in elderly oesophageal cancer patients

We present a single institution experience with 5-FU, mitomycin-C based chemoradiation for the primary treatment of elderly patients with oesophageal cancer. Twenty-five patients with a median age of 77 years (range 66-88) with a diagnosis of stage II-III squamous cell or adenocarcinoma of the oesophagus were treated at Memorial Sloan Kettering from 1996 to 2001 with two cycles of concurrent 5-FU, mitomycin-C and 50.4 Gy. Owing to age and comorbidity, these patients were not considered surgical candidates. The Charlson comorbidity score was used to evaluate patient comorbidity. Nine patients (36%) experienced grade 3-4 haematologic toxicity. Of the 23 patients evaluable for response, 17 patients (68%) had a negative post-treatment endoscopy and CT scan without evidence of progressive disease. Eleven patients (44%) are alive and 10 (40%) remain without evidence of recurrent or progressive oesophageal cancer at a median follow-up of 35 months. The median overall survival was 35 months and 2-year survival 64%. There was no significant difference in overall survival between Charlson score /=2 (P=0.10). Similar survival was observed for patients with adenocarcinoma or squamous carcinoma. Primary chemoradiation with two cycles of 5-FU, mitomycin-C, and 50.4 Gy in elderly patients is an active regimen with moderate toxicity, despite the advanced age and heavy comorbidity burden of this cohort. Patients with local/regional oesophageal cancer with adequate functional status should not be excluded from potentially curative treatment based on age alone.

Incorporation of biologic therapies in the management of gastroesophageal cancers

Gastroesophageal malignancies are highly aggressive tumors with mortality rates remaining close to incidence rates; the majority of patients have advanced incurable disease at diagnosis. Although patients receive palliative benefit from chemotherapy, 5-year survival rates remain dismally low. In the past few decades, significant progress in understanding tumor biology has led to development of therapies that target critical aspects of the oncogenic pathway. Such targets include cell growth regulators (human epidermal growth factor like receptor, Ki-67), vascular modulators (vascular endothelial growth factor), cell cycle checkpoint modulators (p16, p21, cyclin D1, cyclindependent kinases), apoptosis promoters (p53, bax, bcl-2), and cell proliferators, tissue invasion and metastasis potentiators (matrix metalloproteinase, E-cadherin, gastrin 17). Clinical assessment of the inhibition of some of these targets is under way in various tumor types, including gastroesophageal cancers. This paper reviews emerging data on selected molecular targets and their antitumor potential in gastroesophageal malignancies.

Phase II trial of preoperative cisplatin-irinotecan followed by concurrent cisplatin-irinotecan and radiotherapy: PET scan after induction therapy may identify early treatment failure

4023

Background: Response on PET scan during preoperative chemotherapy (chemo) for esophageal cancer (EC) has prognostic significance [JCO 19:3058;2001]. Induction chemo with weekly irinotecan(I)/cisplatin(C) relieves dysphagia, and weekly I/C administered with radiotherapy (RT) is well tolerated [ProcASCO 23:Abs 4017;2005]. We completed a Phase II trial of induction I/C followed by I/C/RT followed by surgery. Repeat PET scan was performed after induction chemo and prior to RT. Methods: Patients (pts) with resectable EC/GE junction carcinoma were staged with EUS, PET, and CT scan. Induction chemo consisted of I-65 mg/m2 and C-30 mg/m2 weeks 1,2,4,5, and weeks 7,8,10,11 with RT (180 cGy daily fractions to 5040 cGy). PET scan was repeated at week 6. Esophagectomy was planned 4–8 weeks after RT. Results: 60 pts were enrolled: 6 inevaluable, 54 evaluable, 3 await surgery; 49 male (91%), 5 female (9%), 41 adenocarcinoma (76%), 13 squamous (24%), median age 59, median PS 0, EUS T3N1 35 (65%), N1 40 (74%). Of 41 pts with dysphagia, 31 (76%) had resolution/improvement with induction chemo and 3/54 (6%) required a feeding tube. Of 51 pts, 3 clinical complete responders (CR) deferred surgery (1 refusal, 2 medically inoperable). Of 48 pts, 4 progressed during induction (8%), 9 progressed during RT (19%), and 35 underwent R0 resection (73%). 9/48 (19%) achieved pathologic CR. The median overall survival was 35.4 mos (median follow up 15 mos). In exploratory analysis in 54 pts, response after induction on the week 6 PET scan measured as a decline in SUV, correlated with time to tumor progression (TTP). The mean change in SUV was 43%. A set point of 22% or greater decline in SUV (PET responder) yielded the greatest distinction in TTP (PET responders TTP 18.5 mos, vs nonresponders 5.5 mos, p = 0.03). 4 pts with progression during induction crossed over to RT with paclitaxel: 3 (2 squamous, 1 adenocarcinoma) achieved durable disease control (one pathologic CR, one pathologic PR, one clinical CR). Conclusions: Response on PET scan during induction chemo for EC may identify early treatment failures, and may direct pts to successful salvage with alternative chemo during RT. Supported by a grant from Pfizer.

[Table: see text]

Adjuvant therapy for stage II colorectal cancer: Who and with what?

The role of adjuvant chemotherapy for patients with stage II colon adenocarcinoma remains controversial. The high surgical cure rate for patients with "low-risk" stage II colon cancer, ranging from 75% to 80%, and the available clinical trials and meta-analyses provide conflicting recommendations for or against adjuvant chemotherapy for this group of patients. For fit "high-risk" stage II patients with clinical obstruction or perforation at presentation, in which the 5-year survival rate is 60% to 70%, there is little controversy, as these patients are routinely treated with adjuvant chemotherapy. Other potential high-risk factors, including high histologic grade, microsatellite instability, and loss of 18q, have yet to be validated in prospective trials. Patients with fewer than 12 regional lymph nodes identified in the surgical specimen have a statistically unclear risk of lymph node involvement. These patients may have stage III disease and should receive adjuvant therapy. The decision to use adjuvant chemotherapy to treat low-risk stage II colon cancer patients (no obstruction or perforation) should be an informed decision weighing the magnitude of a net 2% to 5% survival benefit, a 0.5% to 1.0% risk of mortality with chemotherapy in addition to 6 months of chemotherapy-related toxicities, other coexisting patient morbidities, and the anticipated life expectancy of each patient. As adjuvant chemotherapy is therapy addressing local or metastatic microscopic disease, and the effectiveness of systemic and biologically targeted therapy for advanced macroscopic colon cancer continues to improve rapidly, it remains to be determined by clinical trials whether therapies including newer agents such as cetuximab and bevacizumab administered in the adjuvant setting may affect survival for stage II cancer patients.

Pelvic CT in patients with esophageal cancer

OBJECTIVE

Our aim was to determine whether pelvic CT scans reveal clinically relevant information that would change treatment in the initial or follow-up radiologic examination of patients with esophageal cancer.

CONCLUSION

We observed that the addition of pelvic CT to 201 examinations of the chest and abdomen had a minimal effect on patient treatment. No pelvic examination changed the cancer stage, but three pelvic CT scans in three patients (3%) altered treatment.

Irinotecan, cisplatin, and radiation in esophageal cancer

The limited effectiveness of currently available chemotherapy in the treatment of advanced esophageal cancer, and the poor survival achieved in locally advanced disease with combined chemoradiotherapy with or without surgery, have prompted the evaluation of new agents. Irinotecan (CPT-11, Camptosar) has promising single-agent activity in gastrointestinal cancers. In phase II evaluation of weekly irinotecan plus cisplatin, response rates have exceeded 30% in esophageal and gastric cancers. Irinotecan is an active radiosensitizer in preclinical studies and clinical trials in lung cancer. We performed a phase I trial of weekly irinotecan, cisplatin, and concurrent radiotherapy in locally advanced esophageal cancer. Induction chemotherapy with irinotecan and cisplatin was given prior to radiotherapy, over 6 weeks, cycled on a 2-week-on, 1-week-off schedule to relieve dysphagia. Radiotherapy was given subsequently in 180-cGy daily fractions to a total dose of 5,040 cGy. Doses of chemotherapy, when given with concurrent radiotherapy, were cisplatin at 30 mg/m2 followed by irinotecan at escalated doses (40, 50, 65, and 80 mg/m2), on days 1, 8, 22, and 29. Among 18 patients entered in the trial, minimal toxicity has been observed, with no grade 3/4 esophagitis or diarrhea. Hematologic toxicity has been minimal. Dose-limiting toxicity (ie, requiring more than a 2-week delay in radiotherapy) has been seen in one of three patients at the 80-mg/M2 irinotecan dose level, and accrual continues at this dose level. Among 13 evaluable patients, five complete responses have been seen (38%), including three pathologic complete responses in 10 patients undergoing surgery (30%). Asymptomatic pulmonary emboli were noted on the posttreatment computed tomography scan in 3 of 15 patients, prompting the addition of warfarin sodium (Coumadin) prophylaxis on protocol. Full doses of weekly irinotecan (65 mg/ m2) and cisplatin (30 mg/m2) can be combined safely with concurrent radiotherapy in patients with locally advanced esophageal cancer.

Phase I study of the cyclin-dependent kinase inhibitor flavopiridol in combination with paclitaxel in patients with advanced solid tumors

PURPOSE

Preclinical studies indicate that the cyclin-dependent kinase inhibitor flavopiridol potentiates the induction of apoptosis by paclitaxel, provided paclitaxel is followed by flavopiridol. We therefore designed a phase I clinical trial of sequential paclitaxel and flavopiridol.

PATIENTS AND METHODS

Paclitaxel was administered at a fixed dose, as either a 24- or 3-hour infusion on day 1, followed by a 24-hour infusion of flavopiridol on day 2. Doses of flavopiridol were escalated in successive cohorts according to a modified Fibonacci design. Flavopiridol pharmacokinetics were obtained on all patients.

RESULTS

Dose-limiting neutropenia developed with 24-hour paclitaxel doses of 135 and 100 mg/m(2) and flavopiridol doses of 10 and 20 mg/m(2), respectively. With 3-hour paclitaxel at 100 mg/m(2), flavopiridol could be escalated to 70 mg/m(2) without dose-limiting toxicity. With 3-hour paclitaxel next escalated to 135 mg/m(2), dose-limiting neutropenia and pulmonary toxicity occurred when flavopiridol was escalated to 94 mg/m(2). This did not correlate with any change in flavopiridol or paclitaxel pharmacokinetics. At a 3-hour paclitaxel dose of 175 mg/m(2), dose-limiting pulmonary toxicity occurred in only one patient at flavopiridol doses under 94 mg/m(2). Clinical activity was observed in patients with esophagus, lung, and prostate cancer, including patients who had progressed on paclitaxel.

CONCLUSION

The recommended phase II doses will be a 3-hour infusion of paclitaxel at 175 mg/m(2) on day 1 followed by a 24-hour infusion of flavopiridol at 70 mg/m(2) on day 2. Flavopiridol dose escalations to 80 mg/m(2) are possible. At these doses, toxicities are manageable and clinical activity is promising.