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Marcia Irene Canto

Publications and source records attributed to Marcia Irene Canto.

11 recordsLinked to original sources
PubMed2025

Personalizing CA125 Levels Using Tumor Marker Variants: A Case-Control Analysis of Diagnostic Performance for Pancreatic Cancer.

BACKGROUND: Cancer antigen 125 (CA125) is widely recognized as a useful biomarker for the surveillance of patients with ovarian and other cancers. Prior genome-wide association studies have identified variants that influence CA125 levels. We evaluated the utility of stratifying CA125 levels by such variants and evaluated diagnostic performance in control subjects and patients with pancreatic ductal adenocarcinoma (PDAC). METHODS: We measured CA125 levels in 807 control subjects and 450 patients with PDAC and genotyped 10 variants involving four genes (GAL3ST2, MSLN, D2HGDH, and MUC16). We compared CA125 levels in controls by variant and generated variant-defined CA125 cutoffs and then classified cases and controls into functional groups based on their variant profile. We used this variant classification to evaluate the diagnostic performance of CA125 in patients with PDAC. RESULTS: Six variants associated with CA125 levels were used to group controls into one of four groups. Mean CA125 levels in the highest variant group were approximately fourfold higher than in the lowest group. African Americans were more likely to have a variant group associated with low CA125 levels. After setting diagnostic cutoffs by variant group, the diagnostic sensitivity of CA125 for PDAC was 20.2% at 98% specificity (areas under the ROC curve, 0.702), not significantly different from a uniform CA125 diagnostic cutoff (areas under the ROC curve, 0.700). CONCLUSIONS: Gene variants can be used to generate personalized CA125 reference ranges. This approach did not significantly improve CA125's diagnostic performance for pancreatic cancer, but it merits evaluation in other diagnostic settings, such as detecting ovarian cancer. IMPACT: Gene variants can be used to personalize CA125 levels.

Humans↗
PubMed2006

Screening for early pancreatic neoplasia in high-risk individuals: a prospective controlled study.

BACKGROUND & AIMS: Individuals with a strong family history of pancreatic cancer and persons with Peutz-Jeghers syndrome (PJS) have an increased risk for pancreatic cancer. This study screened for early pancreatic neoplasia and compared the pancreatic abnormalities in high-risk individuals and control subjects. METHODS: High-risk individuals with PJS or a strong family history of pancreatic cancer were prospectively evaluated with baseline and 12-month computed tomography (CT) scan and endoscopic ultrasonography (EUS). If EUS was abnormal, EUS-fine-needle aspiration and endoscopic retrograde cholangiopancreatography (ERCP) were performed. Surgery was offered to patients with potentially neoplastic lesions. Radiologic findings and pathologic diagnoses were compared. Patients undergoing EUS and/or ERCP for benign non-pancreatic indications were concurrently enrolled as control subjects. RESULTS: Seventy-eight high-risk patients (72 from familial pancreatic cancer kindreds, 6 PJS) and 149 control patients were studied. To date, 8 patients with pancreatic neoplasia have been confirmed by surgery or fine-needle aspiration (10% yield of screening); 6 patients had 8 benign intraductal papillary mucinous neoplasms (IPMNs), 1 had an IPMN that progressed to invasive ductal adenocarcinoma, and 1 had pancreatic intraepithelial neoplasia. EUS and CT also diagnosed 3 patients with 5 extrapancreatic neoplasms. At EUS and ERCP abnormalities suggestive of chronic pancreatitis were more common in high-risk patients than in control subjects. CONCLUSIONS: Screening EUS and CT diagnosed significant asymptomatic pancreatic and extrapancreatic neoplasms in high-risk individuals. IPMN should be considered a part of the phenotype of familial pancreatic cancer. Abnormalities suggestive of chronic pancreatitis are identified more commonly at EUS and ERCP in high-risk individuals.

Adult↗
PubMed2006

Management of high-grade dysplasia in patients with Barrett's esophagus.

In the past, the standard management for patients with high-grade dysplasia in Barrett's esophagus was esophagectomy, in part on the basis of the assumption that the patient was likely to harbor an undetected carcinoma. With better awareness of the safety of surveillance protocols, improved prospective surveillance, and experience with cohorts of patients in whom incident early lesions unassociated with invasive carcinomas are detected, endoscopic techniques for treatment of Barrett-associated neoplasia have become excellent alternatives to esophagectomy for appropriately selected patients. Emerging endoscopic techniques offer an opportunity for better evaluation of patients with Barrett's-associated neoplasia.

Barrett Esophagus↗
PubMed2005

Barrett's esophagus.

Esophageal cancer staging is a widely accepted indication for endoscopic ultrasonography (EUS). The evaluation of Barrett's esophagus (BE) with EUS is indicated only when there is high-grade dysplasia or a concern for malignancy in an endoscopic lesion. Because the options for the management of BE and early adenocarcinoma are diverse, proper selection of patients by accurate staging with EUS is critical, particularly when nonoperative management is considered. For example, patients with BE with high-grade dysplasia may be offered esophagectomy in some medical centers, but nonoperative therapies such as endoscopic ablative therapy or mucosal resection may be the preferred treatment options in other gastroenterology practices. This article discusses the scientific evidence for the use of EUS in BE or early esophageal adenocarcinoma.

Adenocarcinoma↗
PubMed2005

Chromoendoscopy and magnifying endoscopy for Barrett's esophagus.

Chromoendoscopy and magnification endoscopy are 2 endoscopic techniques used to improve visualization and diagnosis of gastrointestinal mucosa. This article summarizes the principles behind magnification endoscopy, with and without chromoendoscopy, for the diagnosis of Barrett's esophagus, dysplasia, and adenocarcinoma. Furthermore, this article discusses the possible clinical use of magnification endoscopy and chromoendoscopy in evaluating patients with chronic gastroesophageal reflux disease and Barrett's esophagus.

Barrett Esophagus↗
PubMed2005

Screening for pancreatic neoplasia in high-risk individuals: who, what, when, how?

Pancreatic cancer (PC) is a highly lethal disease. Most symptomatic, clinically detected PCs are advanced and not curable. Indeed, the estimated 5-year survival rate is 4%, which is attributable to late diagnosis and low resection rate. Screening of high-risk individuals and early detection of small PCs and precursor lesions might improve the outcome if curative therapy could be offered in the presymptomatic stage. This article summarizes the available published data and preliminary results and discusses the different approaches to screening for pancreatic neoplasia at 2 university-based programs in the United States.

Humans↗
PubMed2004

Screening for pancreatic neoplasia in high-risk individuals: an EUS-based approach.

BACKGROUND & AIMS: Relatives of patients with pancreatic cancer and persons with certain inherited syndromes are at increased risk for developing pancreatic cancer. We prospectively evaluated the feasibility of screening for pancreatic neoplasia in high-risk individuals. METHODS: Individuals from familial pancreatic cancer kindreds and a patient with Peutz-Jeghers syndrome underwent screening endoscopic ultrasound (EUS). If the EUS was abnormal, EUS-guided fine-needle aspiration, endoscopic retrograde cholangiopancreatography (ERCP), and spiral computed tomography (CT) were performed. Patients with abnormalities suggesting neoplasia had surgery. RESULTS: Thirty-eight patients were studied; 31 (mean age, 58 yr; 42% men) from kindreds with > or =3 affected with pancreatic cancer; 6 from kindreds with 2 affected relatives, 1 was a patient with Peutz-Jeghers syndrome. None had symptoms referable to the pancreas or suggestive of malignancy. Six pancreatic masses were found by EUS: 1 invasive ductal adenocarcinoma, 1 benign intraductal papillary mucinous neoplasm, 2 serous cystadenomas, and 2 nonneoplastic masses. Hence, the diagnostic yield for detecting clinically significant pancreatic neoplasms was 5.3% (2 of 38). The 1 patient with pancreatic cancer was treated and still is alive and disease-free >5 years after surgery. EUS changes similar to those associated with chronic pancreatitis were found, which were more common in patients with a history of regular alcohol intake (P = 0.02), but also occurred in patients who did not consume alcohol. Screening also led to a new diagnosis and treatment of symptomatic upper-gastrointestinal conditions in 18.4% of patients. CONCLUSIONS: EUS-based screening of asymptomatic high-risk individuals can detect prevalent resectable pancreatic neoplasia but false-positive diagnoses also occur.

Age Distribution↗
PubMed2002

The adoption of ablation therapy for Barrett's esophagus: a cohort study of gastroenterologists.

OBJECTIVES: Although ablation therapy may be useful in the treatment of Barrett's esophagus. evidence of effectiveness is scarce, and little is known about current utilization of ablation. We aimed to determine whether the use of ablation was increasing in a cohort of gastroenterologists, and to identify physician beliefs and characteristics associated with ablation use. METHODS: We surveyed a national sample of gastroenterologists about ablation use, with an 18-month follow-up. The self-administered instrument included questions about demographic characteristics, attitudes about ablation therapy, and prior experience with ablation. Case scenarios were also included. We used logistic regression to identify factors associated with the use of ablation in patients with Barrett's esophagus. RESULTS: Two hundred seventy-nine (50.3% of those eligible) responded to the baseline survey. Few agreed that ablation lowers the risk of adenocarcinoma (15%) or is supported by the medical literature (19%). However, 25% of respondents reportedly had used ablation at baseline, and this increased to 36% in the follow-up survey (p = 0.0003). The use of ablation was significantly associated with physician age greater than 54 yr (odds ratio [OR] = 2.77, 95% CI = 1.04-7.37) and the belief that ablation was used by colleagues (OR = 13.27, 95% CI = 4.44-39.64) or decreases medical costs (OR = 5.07, 95% CI = 1.00-25.74). CONCLUSIONS: Although few gastroenterologists agreed that ablation is effective, a significant proportion had adopted its use. There was a significant increase in ablation use during our study period, and the characteristic that was most strongly associated with ablation use was the belief that colleagues used it.

Adult↗