Dawn Q. Chong

The landscape of targeted therapies for cholangiocarcinoma: current status and emerging targets

Cholangiocarcinoma (CCA) is a relatively rare malignancy that arises from the epithelial cells of the intrahepatic, perihilar and distal biliary tree. Intrahepatic CCA (ICC) represents the second most common primary liver cancer, after hepatocellular cancer. Two-thirds of the patients with ICC present with locally advanced or metastatic disease. Despite standard treatment with gemcitabine and cisplatin, prognosis remains dismal with a median survival of less than one year. Several biological plausibilities can account for its poor clinical outcomes. First, despite the advent of next generation and whole exome sequencing, no oncogenic addiction loops have been validated as clinically actionable targets. Second, the anatomical, pathological and molecular heterogeneity, and rarity of CCA confer an ongoing challenge of instituting adequately powered clinical trials. Last, most of the studies were not biomarker-driven, which may undermine the potential benefit of targeted therapy in distinct subpopulations carrying the unique molecular signature. Recent whole genome sequencing efforts have identified known mutations in genes such as epidermal growth factor receptor (EGFR), Kirsten rat sarcoma viral oncogene homolog (KRAS), v-raf murine sarcoma viral oncogene homolog (BRAF) and tumor protein p53 (TP53), novel mutations in isocitrate dehydrogenase (IDH), BRCA1-Associated Protein 1 (BAP1) and AT-rich interactive domain-containing protein 1A (ARID1A), and novel fusions such as fibroblast growth factor receptor 2 (FGFR2) and ROS proto-oncogene 1 (ROS1). In this review, we will discuss the evolving genetic landscape of CCA, with an in depth focus on novel fusions (e.g. FGFR2 and ROS1) and somatic mutations (e.g. IDH1/2), which are promising actionable molecular targets.

Prognosis and Clinicopathologic Features of Patients With Advanced Stage Isocitrate Dehydrogenase (IDH) Mutant and IDH Wild-Type Intrahepatic Cholangiocarcinoma

BACKGROUND Conflicting data exist regarding the prognostic impact of the isocitrate dehydrogenase (IDH) mutation in intrahepatic cholangiocarcinoma (ICC), and limited data exist in patients with advanced-stage disease. Similarly, the clinical phenotype of patients with advanced IDH mutant (IDHm) ICC has not been characterized. In this study, we report the correlation of IDH mutation status with prognosis and clinicopathologic features in patients with advanced ICC. METHODS Patients with histologically confirmed advanced ICC who underwent tumor mutational profiling as a routine part of their care between 2009 and 2014 were evaluated. Clinical and pathological data were collected by retrospective chart review for patients with IDHm versus IDH wild-type (IDHwt) ICC. Pretreatment tumor volume was calculated on computed tomography or magnetic resonance imaging. RESULTS Of the 104 patients with ICC who were evaluated, 30 (28.8%) had an IDH mutation (25.0% IDH1, 3.8% IDH2). The median overall survival did not differ significantly between IDHm and IDHwt patients (15.0 vs. 20.1 months, respectively; p = .17). The pretreatment serum carbohydrate antigen 19-9 (CA19-9) level in IDHm and IDHwt patients was 34.5 and 118.0 U/mL, respectively (p = .04). Age at diagnosis, sex, histologic grade, and pattern of metastasis did not differ significantly by IDH mutation status. CONCLUSION The IDH mutation was not associated with prognosis in patients with advanced ICC. The clinical phenotypes of advanced IDHm and IDHwt ICC were similar, but patients with IDHm ICC had a lower median serum CA19-9 level at presentation. IMPLICATIONS FOR PRACTICE Previous studies assessing the prognostic impact of the isocitrate dehydrogenase (IDH) gene mutation in intrahepatic cholangiocarcinoma (ICC) mainly focused on patients with early-stage disease who have undergone resection. These studies offer conflicting results. The target population for clinical trials of IDH inhibitors is patients with unresectable or metastatic disease, and the current study is the first to focus on the prognosis and clinical phenotype of this population and reports on the largest cohort of patients with advanced IDH mutant ICC to date. The finding that the IDH mutation lacks prognostic significance in advanced ICC is preliminary and needs to be confirmed prospectively in a larger study.

Nsaid use and risk of hepatocellular carcinoma and intrahepatic cholangiocarcinoma: The liver cancer pooling project

Chronic inflammation plays a pivotal role in the pathogenesis of hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC), the two most common types of liver cancer. A number of prior experimental studies have suggested that nonsteroidal anti-inflammatory drugs (NSAIDs), including aspirin and ibuprofen, may potentially protect against liver cancer. However, no observational study has examined the association between aspirin duration and dose or other over-the-counter non-aspirin NSAIDs, such as ibuprofen, and liver cancer incidence. Furthermore, the association between NSAID use and risk of ICC is unclear. As part of the Liver Cancer Pooling Project, we harmonized data on 1,084,133 individuals (HCC = 679, ICC = 225) from 10 U.S.-based prospective cohort studies. Cox proportional hazards regression models were used to evaluate multivariable-adjusted HRs and 95% confidence intervals (CI). Current aspirin use, versus nonuse, was inversely associated with HCC (HR, 0.68; 95% CI, 0.57–0.81), which persisted when restricted to individuals not using non-aspirin NSAIDs and in a 5- and 10-year lag analysis. The association between aspirin use and HCC risk was stronger for users who reported daily use, longer duration use, and lower dosage. Ibuprofen use was not associated with HCC risk. Aspirin use was associated with a reduced ICC risk in men (HR, 0.64; 95% CI, 0.42–0.98) but not women (HR, 1.34; 95% CI, 0.89–2.01; Pinteraction = 0.01). The observed inverse association between aspirin use and liver cancer in our study, together with previous data, suggests the merit of future intervention studies of aspirin and other agents that affect chronic inflammatory pathways for HCC and possibly ICC. Cancer Prev Res; 8(12); 1156–62. ©2015 AACR.

Coffee consumption and risk of hepatocellular carcinoma and intrahepatic cholangiocarcinoma by sex: The Liver Cancer Pooling Project

Background: Coffee consumption has been reported to be inversely associated with hepatocellular carcinoma (HCC), the most common type of liver cancer. Caffeine has chemopreventive properties, but whether caffeine is responsible for the coffee–HCC association is not well studied. In addition, few studies have examined the relationship by sex, and no studies have examined whether there is an association between coffee and intrahepatic cholangiocarcinoma (ICC), the second most common type of liver cancer. Methods: In the Liver Cancer Pooling Project, a consortium of U.S.-based cohort studies, data from 1,212,893 individuals (HCC, n = 860; ICC, n = 260) in nine cohorts were pooled. Multivariable-adjusted hazard ratios (HR) and 95% confidence intervals (CI) were estimated using proportional hazards regression. Results: Higher coffee consumption was associated with lower risk of HCC (HR>3 cups/day vs. non-drinker, 0.73; 95% CI, 0.53–0.99; Ptrend cups/day = <0.0001). More notable reduced risk was seen among women than men (Pinteraction = 0.07). Women who consumed more than three cups of coffee per day were at a 54% lower risk of HCC (HR, 0.46; 95% CI, 0.26–0.81), whereas men had more modest reduced risk of HCC (HR, 0.93; 95% CI, 0.63–1.37). The associations were stronger for caffeinated coffee (HR>3 cups/day vs. non-drinker, 0.71; 95% CI, 0.50–1.01) than decaffeinated coffee (HR, 0.92; 95% CI, 0.55–1.54). There was no association between coffee consumption and ICC. Conclusions: These findings suggest that, in a U.S. population, coffee consumption is associated with reduced risk of HCC. Impact: Further research into specific coffee compounds and mechanisms that may account for these associations is needed. Cancer Epidemiol Biomarkers Prev; 24(9); 1398–406. ©2015 AACR.

Body Mass Index, Waist Circumference, Diabetes, and Risk of Liver Cancer for U.S. Adults.

Incidence rates for liver cancer have increased 3-fold since the mid-1970s in the United States in parallel with increasing trends for obesity and type II diabetes mellitus. We conducted an analysis of baseline body mass index (BMI), waist circumference (WC), and type II diabetes mellitus with risk of liver cancer. The Liver Cancer Pooling Project maintains harmonized data from 1.57 million adults enrolled in 14 U.S.-based prospective studies. Cox regression estimated HRs and 95% confidence intervals (CI) adjusted for age, sex, study center, alcohol, smoking, race, and BMI (for WC and type II diabetes mellitus). Stratified analyses assessed whether the BMI-liver cancer associations differed by hepatitis sera-positivity in nested analyses for a subset of cases (n = 220) and controls (n = 547). After enrollment, 2,162 incident liver cancer diagnoses were identified. BMI, per 5 kg/m2, was associated with higher risks of liver cancer, more so for men (HR = 1.38; 95% CI, 1.30-1.46) than women (HR = 1.25; 95% CI, 1.17-1.35; Pinteraction = 0.02). WC, per 5 cm, was associated with higher risks of liver cancer, approximately equally by sex (overall, HR = 1.08; 95% CI, 1.04-1.13). Type II diabetes mellitus was associated with higher risk of liver cancer (HR = 2.61; 95% CI, 2.34-2.91). In stratified analyses, there was a null association between BMI and liver cancer risk for participants who were sera-positive for hepatitis. This study suggests that high BMI, high WC, and type II diabetes mellitus are associated with higher risks of liver cancer and that the association may differ by status of viral hepatitis infection. Cancer Res; 76(20); 6076-83. ©2016 AACR.

Relationship of prediagnostic body mass index with survival after colorectal cancer: Stage-specific associations

Higher body mass index (BMI) is a well‐established risk factor for colorectal cancer (CRC), but is inconsistently associated with CRC survival. In 6 prospective studies participating in the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO), 2,249 non‐Hispanic white CRC cases were followed for a median 4.5 years after diagnosis, during which 777 died, 554 from CRC‐related causes. Associations between prediagnosis BMI and survival (overall and CRC‐specific) were evaluated using Cox regression models adjusted for age at diagnosis, sex, study and smoking status (current/former/never). The association between BMI category and CRC survival varied by cancer stage at diagnosis (I‐IV) for both all‐cause (p‐interaction = 0.03) and CRC‐specific mortality (p‐interaction = 0.04). Compared to normal BMI (18.5–24.9 kg/m2), overweight (BMI 25.0–29.9) was associated with increased mortality among those with Stage I disease, and decreased mortality among those with Stages II–IV disease. Similarly, obesity (BMI ≥30) was associated with increased mortality among those with Stages I–II disease, and decreased mortality among those with Stages III–IV disease. These results suggest the relationship between BMI and survival after CRC diagnosis differs by stage at diagnosis, and may emphasize the importance of adequate metabolic reserves for colorectal cancer survival in patients with late‐stage disease.

Relationship of prediagnostic body mass index with survival after colorectal cancer

Higher body mass index (BMI) is a well‐established risk factor for colorectal cancer (CRC), but is inconsistently associated with CRC survival. In 6 prospective studies participating in the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO), 2,249 non‐Hispanic white CRC cases were followed for a median 4.5 years after diagnosis, during which 777 died, 554 from CRC‐related causes. Associations between prediagnosis BMI and survival (overall and CRC‐specific) were evaluated using Cox regression models adjusted for age at diagnosis, sex, study and smoking status (current/former/never). The association between BMI category and CRC survival varied by cancer stage at diagnosis (I‐IV) for both all‐cause (p‐interaction = 0.03) and CRC‐specific mortality (p‐interaction = 0.04). Compared to normal BMI (18.5–24.9 kg/m2), overweight (BMI 25.0–29.9) was associated with increased mortality among those with Stage I disease, and decreased mortality among those with Stages II–IV disease. Similarly, obesity (BMI ≥30) was associated with increased mortality among those with Stages I–II disease, and decreased mortality among those with Stages III–IV disease. These results suggest the relationship between BMI and survival after CRC diagnosis differs by stage at diagnosis, and may emphasize the importance of adequate metabolic reserves for colorectal cancer survival in patients with late‐stage disease.

Genetic variation in the ADIPOQ gene, adiponectin concentrations and risk of colorectal cancer: a Mendelian Randomization analysis using data from three large cohort studies

Higher levels of circulating adiponectin have been related to lower risk of colorectal cancer in several prospective cohort studies, but it remains unclear whether this association may be causal. We aimed to improve causal inference in a Mendelian Randomization meta-analysis using nested case–control studies of the European Prospective Investigation into Cancer and Nutrition (EPIC, 623 cases, 623 matched controls), the Health Professionals Follow-up Study (HPFS, 231 cases, 230 controls) and the Nurses’ Health Study (NHS, 399 cases, 774 controls) with available data on pre-diagnostic adiponectin concentrations and selected single nucleotide polymorphisms in the ADIPOQ gene. We created an ADIPOQ allele score that explained approximately 3% of the interindividual variation in adiponectin concentrations. The ADIPOQ allele score was not associated with risk of colorectal cancer in logistic regression analyses (pooled OR per score-unit unit 0.97, 95% CI 0.91, 1.04). Genetically determined twofold higher adiponectin was not significantly associated with risk of colorectal cancer using the ADIPOQ allele score as instrumental variable (pooled OR 0.73, 95% CI 0.40, 1.34). In a summary instrumental variable analysis (based on previously published data) with higher statistical power, no association between genetically determined twofold higher adiponectin and risk of colorectal cancer was observed (0.99, 95% CI 0.93, 1.06 in women and 0.94, 95% CI 0.88, 1.01 in men). Thus, our study does not support a causal effect of circulating adiponectin on colorectal cancer risk. Due to the limited genetic determination of adiponectin, larger Mendelian Randomization studies are necessary to clarify whether adiponectin is causally related to lower risk of colorectal cancer.

Tobacco, alcohol use and risk of hepatocellular carcinoma and intrahepatic cholangiocarcinoma: The Liver Cancer Pooling Project

BackgroundWhile tobacco and alcohol are established risk factors for hepatocellular carcinoma (HCC), the most common type of primary liver cancer, it is unknown whether they also increase the risk of intrahepatic cholangiocarcinoma (ICC). Thus, we examined the association between tobacco and alcohol use by primary liver cancer type.MethodsThe Liver Cancer Pooling Project is a consortium of 14 US-based prospective cohort studies that includes data from 1,518,741 individuals (HCC n = 1423, ICC n = 410). Multivariable-adjusted hazards ratios (HRs) and 95% confidence intervals (CI) were estimated using proportional hazards regression.ResultsCurrent smokers at baseline had an increased risk of HCC (hazard ratio (HR) = 1.86, 95% confidence interval (CI): 1.57–2.20) and ICC (HR = 1.47, 95% CI: 1.07–2.02). Among individuals who quit smoking >30 years ago, HCC risk was almost equivalent to never smokers (HR = 1.09, 95% CI: 0.74–1.61). Compared to non-drinkers, heavy alcohol consumption was associated with an 87% increased HCC risk (HR≥7 drinks/day = 1.87, 95% CI: 1.41–2.47) and a 68% increased ICC risk (HR≥5 drinks/day = 1.68, 95% CI: 0.99–2.86). However, light-to-moderate alcohol consumption of <3 drinks/day appeared to be inversely associated with HCC risk (HR>0–<0.5 drinks/day = 0.77, 95% CI: 0.67–0.89; HR>0.5–<1 drinks/day = 0.57, 95% CI: 0.44–0.73; HR1–<3 drinks/day = 0.71, 95% CI: 0.58–0.87), but not ICC.ConclusionsThese findings suggest that, in this relatively healthy population, smoking cessation and light-to-moderate drinking may reduce the risk of HCC.

Addressing the needs of colorectal cancer survivors: current strategies and future directions

Colorectal cancer (CRC) is one of the three topmost common cancers in men and the second most common cancer in women worldwide. With current advances in the medical and surgical treatment of CRC, care has slowly transformed to curative treatment. With these advances, CRC survivors are increasing in numbers and these patients have a unique range of medical, physical and psychological needs that require regular follow-up. In 2006, the Institute of Medicine recommended that cancer survivors who are completing primary treatment receive a survivorship care plan. There are many different programs of different complexity that are implemented for CRC survivors. This review outlines the needs of CRC survivors, the current surveillance techniques used in the continuing care of patients with CRC after curative treatment and the evidence behind these strategies.