ReviewsDesmoplasia and Biophysics in Pancreatic Ductal Adenocarcinoma Can We Learn From Breast Cancer?Di Maggio, Francesco MD, MChir*; El-Shakankery, Karim Hussien MBChB†Author Information From the *Department of Surgery, Guys and St Thomas NHS Foundation Trust †Department of Medicine, The Royal London Hospital, Barts Health NHS Trust, London, United Kingdom. Received for publication April 4, 2019; accepted January 16, 2020. Address correspondence to: Karim Hussien El-Shakankery, MBChB, Department of Medicine, The Royal London Hospital, Barts Health NHS Trust, London, United Kingdom (e-mail: Karim.firstname.lastname@example.org; Karimhussien.email@example.com). The two authors equally contributed to the manuscript. The authors declare no conflict of interest. Pancreas: March 2020 - Volume 49 - Issue 3 - p 313-325 doi: 10.1097/MPA.0000000000001504 Buy Metrics Abstract Pancreatic ductal adenocarcinoma (PDAC) treatments have historically focused on targeting tumor cells directly. However, in pancreatic masses, the stroma encasing the malignant epithelial cells constitutes up to 80% to 90% of the tumor bulk. This extracellular matrix, which was previously neglected when designing cancer therapies, is now considered fundamental for tumor progression and drug delivery. Desmoplastic tissue is extensively cross-linked, resulting in tremendous tensile strength. This key pathological feature is procarcinogenic, linking PDAC and breast cancer (BC). Physical forces exerted onto cellular surfaces are detected intracellularly and transduced via biochemical messengers in a process called mechanotransduction. Mechanotransduction and tensional homeostasis are linked, with an integral role in influencing tumor growth, metastasis, and interactions with the immune system. It is essential to enhance our knowledge of these integral elements of parenchymal tumors. We aim to review the topic, with a special emphasis on desmoplastic processes and their importance in pancreatic and BC development and treatments, mindful that innovative diagnostic and therapeutic strategies cannot focus on biochemical pathways alone. We then focus on common therapeutic targets identified in both PDAC and BC models and/or patients, aiming to understand these treatments and draw similarities between the two tumors. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.