Pancreatic cystic lesions are increasingly common incidental findings on abdominal imaging tests. However, the prevalence of pancreatic #cysts varies extremely with the method of imaging used and among studies. Still, even by conservative estimations, 3% of all patients undergoing routine computed tomography (#CT) of the abdomen for unrelated indications are now incidentally found to have a pancreatic cyst [1], [2]. And if the prevalence is detected by #MRI, it ranges from 13-20% [3], [4]. However, autopsy studies have evidenced a much higher number of pancreatic cysts, revealing that up to 50% of the elderly population presented at least one pancreatic cyst at postmortem examinations.
Mucinous cysts constitute the majority of premalignant cysts. The World Health Organization has classified cystic mucin-producing neoplasms of the pancreas into intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic neoplasms (MCNs). These cysts bear a significant #malignant potential to progress to pancreatic cancer [5]. On the other hand, benign cysts such as serous cystic neoplasms (SCNs) and solid pseudopapillary tumors (SPTs) rarely or never give rise to malignant #cancer.
Discrimination between different cyst types is difficult and several studies have reported that there are still not clinically available methods to effectively differentiate pancreatic cysts among benign, premalignant and malignant lesions. In the clinical practice, the accuracy for the discrimination of these cysts ranges from of 43% [6] to 70% [7], the latter reached by physicians with 10+ years of experience in abdominal imaging.
Unfortunately, aside from the assessment of morphological changes on costly and inconvenient serial imaging tests, to date there are no reliable biomarkers to predict #progression of these cyst and usually final diagnosis can only be made on the basis of follow-up examinations, histopathological processing after biopsy or postresection. Importantly, surgery of pancreatic cystic lesions may dramatically reduce the quality of life of the patients as these surgeries come with 50% chance of complications and a 5% chance of death and it has been demonstrated that around 60% of them end up having been unnecessary because the cyst was benign [8]–[10].
What the field needs now is a reliable method for an early differential diagnosis. Here is where #AI can play a key role.
[1] I. K. Ip, K. J. Mortele, L. M. Prevedello, and R. Khorasani, “Focal cystic pancreatic lesions: Assessing variation in radiologists’ management recommendations,” Radiology, vol. 259, no. 1, pp. 136–141, 2011, doi: 10.1148/radiol.10100970.
[2] T. A. Laffan et al., “Prevalence of unsuspected pancreatic cysts on MDCT,” Am. J. Roentgenol., vol. 191, no. 3, pp. 802–807, 2008, doi: 10.2214/AJR.07.3340.
[3] K. S. Lee, A. Sekhar, N. M. Rofsky, and I. Pedrosa, “Prevalence of incidental pancreatic cysts in the adult population on MR imaging.,” Am. J. Gastroenterol., vol. 105, no. 9, pp. 2079–2084, Sep. 2010, doi: 10.1038/ajg.2010.122.
[4] X.-M. Zhang, D. G. Mitchell, M. Dohke, G. A. Holland, and L. Parker, “Pancreatic Cysts: Depiction on Single-Shot Fast Spin-Echo MR Images,” Radiology, vol. 223, no. 2, pp. 547–553, May 2002, doi: 10.1148/radiol.2232010815.
[5] M. Del Chiaro et al., “European evidence-based guidelines on pancreatic cystic neoplasms,” Gut, vol. 67, no. 5, pp. 789–804, 2018, doi: 10.1136/gutjnl-2018-316027.
[6] B. C. Visser, B. M. Yeh, A. Qayyum, L. W. Way, C. E. McCulloch, and F. V. Coakley, “Characterization of cystic pancreatic masses: Relative accuracy of CT and MRI,” Am. J. Roentgenol., vol. 189, no. 3, pp. 648–656, 2007, doi: 10.2214/AJR.07.2365.
[7] D. V. Sahani, N. I. Sainani, M. A. Blake, S. Crippa, M. Mino-Kenudson, and C. Fernandez Del-Castillo, “Prospective evaluation of reader performance on MDCT in characterization of cystic pancreatic lesions and prediction of cyst biologic aggressiveness,” Am. J. Roentgenol., vol. 197, no. 1, pp. 53–61, 2011, doi: 10.2214/AJR.10.5866.
[8] M. G. Keane et al., “Clinical and radiological features that predict malignant transformation in cystic lesions of the pancreas: a retrospective case note review,” AMRC Open Res., vol. 1, p. 4, 2020, doi: 10.12688/amrcopenres.12860.2.
[9] K. V. Anonsen, T. Buanes, B. I. Rosok, T. Hauge, and B. Edwin, “Outcome of laparoscopic surgery in patients with cystic lesions in the distal pancreas,” J. Pancreas, vol. 16, no. 3, pp. 266–270, 2015, doi: 10.6092/1590-8577/2993.
[10] P. J. Allen, “Operative Resection is Currently Overutilized for Cystic Lesions of the Pancreas,” J. Gastrointest. Surg., vol. 18, no. 1, pp. 182–183, 2014, doi: 10.1007/s11605-013-2395-y.
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