This is a very interesting question, but considering the heterogeneity in the precursor lesion of pancreatic ductal adenocarcinoma (PDAC), the doubling time of each cell is different. Ki-67-positive cells show rapid proliferation, while Ki-67-negative quiescent cells correspond to the potentially cancer stem cells located in the niche.   

Thanks Mr Yoshida,

You’re right. Doubling time depends on the cell phenotypic attributes (i.e., being quiescent, proliferative), but I want to know doubling time on average. For example, if a DCIS tumor has 300 cells and after 100 hours tumor cells increases to 600, doubling time is 100 hours.

Diffucult answer. Influences tumor size, grade, age of parient...

Found this article, may be of interest.CANCER June 15, 2003 / Volume 97 / Number 12

Says 120 days (60 to 180) depending grade

Hope helps