Manal Hassan

One hundred years after "carcinoid": epidemiology of and prognostic factors for neuroendocrine tumors in 35,825 cases in the United States.

PURPOSE Neuroendocrine tumors (NETs) are considered rare tumors and can produce a variety of hormones. In this study, we examined the epidemiology of and prognostic factors for NETs, because a thorough examination of neither had previously been performed. METHODS The Surveillance, Epidemiology, and End Results (SEER) Program registries were searched to identify NET cases from 1973 to 2004. Associated population data were used for incidence and prevalence analyses. Results We identified 35,618 patients with NETs. We observed a significant increase in the reported annual age-adjusted incidence of NETs from 1973 (1.09/100,000) to 2004 (5.25/100,000). Using the SEER 9 registry data, we estimated the 29-year limited-duration prevalence of NETs on January 1, 2004, to be 9,263. Also, the estimated 29-year limited-duration prevalence in the United States on that date was 103,312 cases (35/100,000). The most common primary tumor site varied by race, with the lung being the most common in white patients, and the rectum being the most common in Asian/Pacific Islander, American Indian/Alaskan Native, and African American patients. Additionally, survival duration varied by histologic grade. In multivariate analysis of patients with well-differentiated to moderately differentiated NETs, disease stage, primary tumor site, histologic grade, sex, race, age, and year of diagnosis were predictors of outcome (P < .001). CONCLUSION We observed increased reported incidence of NETs and increased survival durations over time, suggesting that NETs are more prevalent than previously reported. Clinicians need to be become familiar with the natural history and patterns of disease progression, which are characteristic of these tumors.

Antidiabetic Therapies Affect Risk of Pancreatic Cancer

BACKGROUND & AIMS Antidiabetic drugs have been found to have various effects on cancer in experimental systems and in epidemiologic studies, although the association between these therapeutics and the risk of human pancreatic cancer has not been explored. We investigated the effect of antidiabetic therapies on the risk of pancreatic cancer. METHODS A hospital-based case-control study was conducted at M. D. Anderson Cancer Center from 2004 to 2008 involving 973 patients with pancreatic adenocarcinoma (including 259 diabetic patients) and 863 controls (including 109 diabetic patients). Information on diabetes history and other risk factors was collected by personal interview. The frequencies of use of insulin, insulin secretagogues, metformin, and other antidiabetic medications among diabetic patients were compared between cases and controls. The risk of pancreatic cancer was estimated using unconditional logistic regression analysis. RESULTS Diabetic patients who had taken metformin had a significantly lower risk of pancreatic cancer compared with those who had not taken metformin (odds ratio, 0.38; 95% confidence interval, 0.22-0.69; P = .001), with adjustments for potential confounders. This difference remained statistically significant when the analysis was restricted to patients with a duration of diabetes >2 years or those who never used insulin. In contrast, diabetic patients who had taken insulin or insulin secretagogues had a significantly higher risk of pancreatic cancer compared with diabetic patients who had not taken these drugs. CONCLUSIONS Metformin use was associated with reduced risk, and insulin or insulin secretagogue use was associated with increased risk of pancreatic cancer in diabetic patients.

Genome-wide association study identifies variants in the ABO locus associated with susceptibility to pancreatic cancer

We conducted a two-stage genome-wide association study of pancreatic cancer, a cancer with one of the lowest survival rates worldwide. We genotyped 558,542 SNPs in 1,896 individuals with pancreatic cancer and 1,939 controls drawn from 12 prospective cohorts plus one hospital-based case-control study. We conducted a combined analysis of these groups plus an additional 2,457 affected individuals and 2,654 controls from eight case-control studies, adjusting for study, sex, ancestry and five principal components. We identified an association between a locus on 9q34 and pancreatic cancer marked by the SNP rs505922 (combined P = 5.37 × 10−8; multiplicative per-allele odds ratio 1.20; 95% confidence interval 1.12–1.28). This SNP maps to the first intron of the ABO blood group gene. Our results are consistent with earlier epidemiologic evidence suggesting that people with blood group O may have a lower risk of pancreatic cancer than those with groups A or B.

The NANETS Consensus Guideline for the Diagnosis and Management of Neuroendocrine Tumors Well-Differentiated Neuroendocrine Tumors of the Jejunum, Ileum, Appendix, and Cecum

Well-differentiated neuroendocrine tumors (NETs) of the jejunum, ileum, and appendix are also collectively known as midgut carcinoids. Similar to NETs in general, the diagnosed incidence of the midgut NETs is on the rise. Their presenting symptoms vary depending on stage and primary site. Local-regional NETs often present with vague and nonspecific symptoms. Classic carcinoid syndrome is more likely to appear in patients with advanced disease. Local-regional NETs of the small bowel should be resected whenever possible. With the exception of small well-differentiated NETs of the appendix, NETs of the midgut have substantial risk of relapse after resection and need to be followed for at least 7 years. Metastatic/advanced NETs of the midgut are incurable. Optimal management requires a multidisciplinary approach. Somatostatin analogs are effective in the management of carcinoid syndrome. Octreotide long-acting release has also recently been shown to delay disease progression. Liver-directed therapy and surgical debulking can improve quality of life in selected patients. Pivotal phase 3 studies with bevacizumab targeting vascular endothelial growth factor and everolimus targeting mTOR (mammalian target of rapamycin) are ongoing and may lead to improved outcome. Further studies of novel approaches such as peptide receptor radiotherapy are also warranted.

Risk Factors for Pancreatic Cancer: Case-Control Study

OBJECTIVES:Although cigarette smoking is the most well-established environmental risk factor for pancreatic cancer, the interaction between smoking and other risk factors has not been assessed. We evaluated the independent effects of multiple risk factors for pancreatic cancer and determined whether the magnitude of cigarette smoking was modified by other risk factors in men and women.METHODS:We conducted a hospital-based case-control study involving 808 patients with pathologically diagnosed pancreatic cancer and 808 healthy frequency-matched controls. Information on risk factors was collected by personal interview, and unconditional logistic regression was used to determine adjusted odds ratios (AORs) by the maximum-likelihood method.RESULTS:Cigarette smoking, family history of pancreatic cancer, heavy alcohol consumption (>60 mL ethanol/day), diabetes mellitus, and history of pancreatitis were significant risk factors for pancreatic cancer. We found synergistic interactions between cigarette smoking and family history of pancreatic cancer (AOR 12.8, 95% confidence interval [CI] 1.6–108.9) and diabetes mellitus (AOR 9.3, 95% CI 2.0–44.1) in women, according to an additive model. Approximately 23%, 9%, 3%, and 5% of pancreatic cancer cases in this study were related to cigarette smoking, diabetes mellitus, heavy alcohol consumption, and family history of pancreatic cancer, respectively.CONCLUSIONS:The significant synergy between these risk factors suggests a common pathway for carcinogenesis of the pancreas. Determining the underlying mechanisms for such synergies may lead to the development of pancreatic cancer prevention strategies for high-risk individuals.

Population-based study of islet cell carcinoma

BackgroundWe examine the epidemiology, natural history, and prognostic factors that affect the duration of survival for islet cell carcinoma by using population-based registries.MethodsThe Surveillance, Epidemiology, and End Results (SEER) Program database (1973–2003 release, April 2006) was used to identify cases of islet cell carcinoma by histology codes and tumor site.ResultsA total of 1310 (619 women and 691 men) cases with a median age of 59 years were identified. The annual age-adjusted incidence in the periods covered by SEER 9 (1973–1991), SEER 13 (1992–1999), and SEER 17 (2000–2003) were .16, .14, and .12 per 100,000, respectively. The estimated 28-year limited duration prevalence on January 1, 2003, in the United States was 2705 cases. Classified by SEER stage, localized, regional, and distant stages corresponded to 14%, 23%, and 54% of cases. The median survival was 38 months. By stage, median survival for patients with localized, regional, and distant disease were 124 (95% CI, 80–168) months, 70 (95% CI, 54–86) months, and 23 (95% CI, 20–26) months, respectively. By multivariate Cox proportional modeling, stage (P < .001), primary tumor location (P = .04), and age at diagnosis (P < .001) were found to be significant predictors of survival.ConclusionsIslet cell carcinomas account for approximately 1.3% of cancers arising in the pancreas. Most patients have advanced disease at the time of diagnosis. Despite the disease’s reputation of being indolent, survival of patients with advanced disease remains only 2 years. Development of novel therapeutic approaches is needed.

Association of diabetes duration and diabetes treatment with the risk of hepatocellular carcinoma.

Despite the observed association between diabetes mellitus and hepatocellular carcinoma (HCC), little is known about the effect of diabetes duration before HCC diagnosis and whether some diabetes medications reduced the risk of HCC development. This objective of the current study was to determine the association between HCC risk and diabetes duration and type of diabetes treatment.

Risk Factors for Intrahepatic and Extrahepatic Cholangiocarcinoma: A Hospital-Based Case–Control Study

BACKGROUND:The risk factors for cholangiocarcinoma are poorly defined in the United States. We evaluated hepatitis C virus (HCV), hepatitis B virus (HBV), and liver cirrhosis as risk factors for intrahepatic cholangiocarcinoma (ICC) and extrahepatic cholangiocarcinoma (ECC).METHODS:A case–control study in which cases were cholangiocarcinoma patients referred to the M.D. Anderson Cancer Center between 1992 and 2002 and controls were healthy individuals. Information about liver diseases, family history, diabetes, smoking, and alcohol consumption were collected on both groups. Blood from all participants was tested for HBV and HCV markers.RESULTS:We identified 246 cases (83 ICC and 163 ECC) and matched them to 236 controls. Compared with controls, ICC patients had a higher prevalence of anti-HCV antibodies (6.0% vs 0.8%, P = 0.01), anti-HBc (9.6% vs 0%, P < 0.0001), and heavy alcohol consumption (21.7% vs 3.8%, P < 0.0001). The adjusted odds ratio and 95% confidence interval (CI) were 7.9 (95% CI 1.3–84.5), 28.6 (95% CI 3.9–1,268.1), and 5.9 (95% CI 2.1–17.4), respectively. Only heavy alcohol consumption was higher in patients with ECC than in controls (17.8% vs 3.8%, P = 0.003). The prevalence of diabetes and smoking were not significantly different between cases (ICC or ECC) and controls. The prevalence of cirrhosis was higher in patients with ICC than those with ECC (24.1% vs 4.9%, P < 0.0001).CONCLUSIONS:Liver cirrhosis and chronic HCV infection are possible risk factors for ICC but not ECC. Heavy alcohol consumption is a risk factor for both ICC and ECC.

Metformin Use Is Associated with Better Survival of Diabetic Patients with Pancreatic Cancer

Purpose: Accumulating evidence suggests that metformin has antitumor activity. The aim of this study was to determine whether metformin use has a survival benefit in patients with pancreatic cancer. Experimental Design: We conducted a retrospective study of patients with diabetes and pancreatic cancer treated at The University of Texas MD Anderson Cancer Center (Houston, TX). Information on diabetes history, including treatment modalities and clinical outcome of pancreatic cancer, was collected using personal interviews and medical record review. Survival analysis was carried out using a Kaplan–Meier plot, log-rank test, and Cox proportional hazards regression models. Results: Among the 302 patients identified, there were no significant differences in demographic or major clinical characteristics between the patients who had received metformin (n = 117) and those who had not (n = 185). The 2-year survival rate was 30.1% for the metformin group and 15.4% for the non-metformin group (P = 0.004; χ2 test). The median overall survival time was 15.2 months for the metformin group, and 11.1 months for the non-metformin group (P = 0.004, log-rank test). Metformin users had a 32% lower risk of death; the HR (95% confidence interval) was 0.68 (0.52–0.89) in a univariate model (P = 0.004), 0.64 (0.48–0.86) after adjusting for other clinical predictors (P = 0.003), and 0.62 (0.44–0.87) after excluding insulin users (P = 0.006). Metformin use was significantly associated with longer survival in patients with nonmetastatic disease only. Conclusions: Our finding that metformin use was associated with improved outcome of patients with diabetes and pancreatic cancer should be confirmed in independent studies. Future research should prospectively evaluate metformin as a supplemental therapy in this population. Clin Cancer Res; 18(10); 2905–12. ©2012 AACR.

Oral Capecitabine for the Treatment of Hepatocellular Carcinoma, Cholangiocarcinoma, and Gallbladder Carcinoma

The goal of the current study was to evaluate the efficacy and toxicity of capecitabine in patients with nonresectable hepatobiliary carcinoma.