By Lynda Williams, medwireNews Reporter
medwireNews: Findings from the Cancer of the Pancreas Screening program in the USA support the use of annual endoscopic ultrasound (EUS) or magnetic resonance imaging (MRI) for patients with a familial or genetic predisposition for pancreatic ductal adenocarcinoma (PDAC).
“Surveillance of high-risk individuals for PDAC using EUS and MRI within established programs at academic centers was observed to lead to the detection of smaller pancreatic cancers, a greater number of patients with stage I disease, lower mortality, and a much higher likelihood of long-term survival than unscreened patients in the general population diagnosed with PDAC”, report Marcia Canto (Johns Hopkins Medicine, Baltimore, Maryland, USA) and co-workers in JAMA Oncology.
As the rarity of PDAC makes it unfeasible to conduct a randomised clinical trial comparing the benefits of surveillance with no surveillance, the team assessed the outcomes of
26 high-risk individuals who had PDAC detected during their participation in the screening programme between 1998 and 2021 with those of 1504 age-, sex- and year of diagnosis-matched PDAC patients included in the Surveillance, Epidemiology, and End Results program, whose cancer was detected outside of screening.
The high-risk patients had either at least one first-degree relative with PDAC and at least one pair of affected first-degree relatives (61.5%), or a known germline mutation associated with hereditary pancreatic cancer in ATM, BRCA1, BRCA2, CDKN2A, PALB2 or STK11 (38.5%).
The high-risk cohort were followed-up for a median of 2.5 years; PDAC was diagnosed at baseline in 23.1% of the patients, while the median time from baseline to diagnosis for the non-prevalent cases was 5.8 years.
At time of diagnosis, the high-risk patients had a significantly smaller primary tumour diameter than the controls (median 2.5 vs 3.6 cm) and were significantly more likely to be diagnosed with stage I (38.5 vs 10.3%) or stage II (30.8 vs 25.1%) disease. High-risk patients were also significantly less likely to have distant disease at diagnosis (26.9 vs 53.8%).
Half of both the high-risk patients and controls had tumours located in the pancreas head, but the high-risk patients were more likely to have tumours in the body or tail (50.0 vs 29.8%) and less likely to have tumours in other sites (0 vs 19.2%).
While the majority of both high-risk patients and controls underwent Whipple procedures (50.0 vs 63.0%), the former were more likely to have distal surgery (44.4 vs 28.0%) and less likely to undergo total pancreatectomy (5.6 vs 9.1%).
Moreover, the 5-year rate of PDAC mortality was significantly lower for the high-risk patients than controls, at 43% versus 86%, with a hazard ratio (HR) for death of 3.58 for non-screened controls versus high-risk patients.
And this was reflected in a significant 4.19-fold longer median overall survival (OS) among the high-risk patients than controls (61.7 vs 8.0 months) and an increase in rates of both 1-year (84 vs 38%) and 5-year OS (50 vs 9%).
Furthermore, among the 20 patients who had screen-detected PDAC, the median OS was 144 months versus a median 9 months for their matched controls, with 5-year OS rates of 61% and 9%, respectively.
“While the current study provides encouraging results and underscores the potential of surveillance and early detection to improve survival of patients with PDAC in a well-defined high-risk cohort, it is unclear whether surveillance outside specialized centers can be recommended”, Canto et al comment.
“The benefits of surveillance have to be weighed against potential harms”, they write, noting the low diagnostic yield of PDAC or high-grade dysplasia at surgery and the risk of false–negative findings.
Nevertheless, the authors conclude: “These findings suggest that selective surveillance of individuals at high risk for pancreatic cancer may improve clinical outcomes.”
News stories are provided by medwireNews, which is an independent medical news service provided by Springer Healthcare Ltd. © 2024 Springer Healthcare Ltd, part of the Springer Nature Group
JAMA Oncol 2024; doi:10.1001/jamaoncol.2024.1930