Letter to the Editor: “Added value of apparent diffusion coefficient distinguishing between serous and mucin-producing pancreatic cyst neoplasms”

by Wisam Sbeit, Moaad Farraj, Anas Kadah, Tawfik Khoury (wisams@gmc.gov.il)

Added value of apparent diffusion coefficient distinguishing between serous and mucin-producing pancreatic cyst neoplasms

Dear Editor,

We read with interest the article by Pallavi Pandey et al entitled ” Added value of apparent diffusion coefficient distinguishing between serous and mucin-producing pancreatic cyst neoplasms” [1]. We congratulate them for their contribution to the evolving field of pancreatic cyst diagnosis by incorporating this noninvasive modality, and would like to shed light and comment on several points in an attempt to make them clearer.

In their “introduction section”, the authors stated that resection is recommended for all patients with worrisome features including cyst > 3 cm, thickened /enhancing cyst walls, main duct size 5-9 mm, non-enhancing mural nodule and abrupt change in caliber of the pancreatic duct with distal pancreatic atrophy according to International consensus guidelines from 2012 [2]. Actually, this statement is mistaken and misleading according to the same guidelines and the American Gastroenterology Association gridlines [3] advocating further investigation by Endoscopic Ultrasound – Fine Needle Aspiration ( EUS- FNA) in this subset of patients, and consider resection only in the presence of “findings suggestive of malignancy” including cytology positive or suspicious of malignancy, definite mural nodule, thickened cyst wall or intraductal mucin suggestive of main duct involvement.

In the “study population section”: Despite the thorough description of the multidisciplinary pancreatic cyst clinic (MPCC) work, which seems very interesting, data of the 68 patients group are obscure and  we could not understand how did they reach the conclusion of “confirmed diagnosis” (according to their announcement). We think it is necessary and more convincing to present all cysts characteristics including imaging findings, cyst fluid analysis and cytology; and we would like to see all these data.

Although histology is the gold standard for cyst type diagnosis, still, EUS-FNA with chemical cyst fluid analysis for Carcino Embryonic Antigen (CEA) play a major role in routine day practice in differentiating mucinous from other pancreatic cyst types [4–6]. In their articles, the authors did not present the values of CEA. We assume that it would be very interesting to compare the results of diffusion-weighted imaging (DWI) in magnetic resonance imaging (MRI) with cyst fluid CEA values, as this may strengthen their conclusion regarding the added value of DWI in differentiation mucinous from other cyst types.

We will be very grateful upon receiving the authors’ response.