The German National Case Collection for Familial Pancreatic Cancer (FaPaCa) Knowledge Gained in 20 Years

Background: Familial pancreatic carcinoma (FPC) is a rare hereditary tumor syndrome with a heterogeneous clinical phenotype. The study of FPC also contributes to a better understanding of the more common sporadic pancreatic ductal adenocarcinoma (PDAC). We report on the past 20 years' experience of the German National Case Collection for Familial Pancreatic Carcinoma (FaPaCa) of the German Cancer Aid (Deutsche Krebshilfe). Methods: From 1999 onward, families in which at least two first-degree relatives had PDAC, and which did not meet the criteria for any other tumor syndrome, have been entered into the FaPaCa registry and analyzed both clinically and with molecular genetic techniques. Persons at risk are offered the opportunity to participate in an early detection program. Results: From June 1999 to June 2019, 227 families (a total of 2579 persons) met the criteria for entry into the FaPaCa registry. PDAC was the sole tumor entity present in 37% of the families (95% confidence interval [31.1; 44.1]); in the remaining 63% [55.9; 68.9], other tumor types were present as well, particularly breast cancer (70 families, 31% [24.9; 37.3]), colon carcinoma (25 families, 11% [7.3; 15.8]), and melanoma (22 families, 9.7% [6.2; 14.3]). The mode of inheritance of PDAC was autosomal dominant in 72% [65.5; 77.6] of the families. Predisposing germ-line mutations were found in 25 of the 150 (16.7%) families studied, in the following genes: BRCA2 (9 families), CDKN2A (5 families), PALB2 (4 families), BRCA1 (3 families), ATM (2 families), and CHEK2 (2 families). The early detection program revealed high-grade cancer precursor lesions or a PDAC in 5 of the participating 110 persons at risk (4.5%, [1.5; 10.3] during a period of observation of at least five years. Conclusion: The care of families with FPC is complex and should be provided in centers with the necessary expertise. Prospective, controlled longitudinal studies are needed to determine whether the screening of persons at risk for PDAC truly lessens mortality and is cost-effective.