Endoscopic ultrasound (EUS) evaluation in patients with locoregional pancreatic cancer can be associated with improved outcomes and may aid earlier detection, according to a study published in the July issue of Gastrointestinal Endoscopy.
Because the symptoms of pancreatic cancer are non-specific and typically occur late in the course of the disease, less than 20 percent of patients have resectable cancer at the time of diagnosis. Complete resection offers the only chance of long-term survival.
Saowanee Ngamruengphong, MD, of the Mayo Clinic in Scottsdale, Ariz., and colleagues conducted the retrospective study to observe any association with survival in patients with pancreatic cancer undergoing EUS.
The researchers utilized the Surveillance Epidemiology and End Results (SEER)–Medicare database to identify 8,616 patients 65 years and older with a pancreatic cancer diagnosis between January 1994 and December 2002. EUS procedural information, demographics and cancer-specific data were also taken from the SEER database. In addition, survival curves were compared for patients who underwent EUS in the peridiagnostic period (one month before the diagnosis to three months after the date of diagnosis, or group I) with those who had not undergone EUS (group II).
Of the 8,616 patients with pancreatic adenocarcinoma, 610 patients (7.1 percent) underwent EUS evaluation. Ngamruengphong and colleagues found that 69.3 percent of group 1 patients presented with early-stage disease compared to 36.2 percent in group II. Moreover, curative-intent surgery, chemotherapy and radiation therapy were also performed more frequently in group I.
Average survival rates were a mean of 10 months for group I and a mean of six months for group II. The authors explained that after adjusting for age, race, sex, tumor stage, curative-intent surgery, chemotherapy, radiation therapy and comorbidity score within group I, EUS was an independent predictor of improved survival.
Despite the study’s findings, improved survival related to undergoing EUS in this study is likely due to many factors as EUS is a diagnostic imaging modality and carries no direct therapeutic impact, noted Ngamruengphong.
EUS evaluation may help identify patients who would most likely benefit from undergoing attempts at curative resection, and the modality may help identify patients with advanced or metastatic pancreatic cancer who would not benefit from curative resection and help them avoid morbidity and mortality related to unnecessary surgery, offered the authors.
Younger age, white race, marriage status, locoregional disease, living in the Midwest region and more recent year of diagnosis were determined to be significant predictors of undergoing EUS, wrote the researchers, noting that the rate of EUS utilization is an increasing in the patient cohort.
“The rate of EUS use in the study patients increased from 0.6 percent in 1994 to 13.1 percent in 2002 … This may reflect increasing availability with dissemination of EUS technology from select academic centers to the community,” they said.
In addition to EUS evaluation resulting in cancers being detected earlier for this patient population, the modality may also improve stage-appropriate management, such as more selective performance of curative-intent surgery and perioperative adjuvant therapy, the study concluded.