Discussion
The Japanese guideline for pancreatic cancer recommends ERCP if there are findings suggestive of pancreatic cancer, such as pancreatic duct dilation or stenosis, even if imaging does not show any evidence of a mass (5). Although no pathologic diagnosis was obtained in our patient using pancreatic juice cytology obtained during ERCP, we were able to make the diagnosis using specimens obtained from SPACE. Iiboshi et al compared patients diagnosed using single pancreatic juice cytology versus SPACE, and report that the sensitivity, specificity, and accuracy of SPACE are 100%, 83.3%, and 95%, respectively (6). The advantage of SPACE lies in its better sensitivity for micropancreatic cancer (4).
According to previous reports, patients with early pancreatic cancer are rarely symptomatic but frequently demonstrate focal branch-duct dilation, focal irregular stenosis, small cystic lesions around the area of ductal stenosis, and distal dilation of the main pancreatic duct on EUS and MRCP (4). In patients with PCIS, assessment with ERCP frequently reveals irregularity, noncontinuous narrowing, granular defects, and dilation. Kikuyama et al report that patients with stage 0 disease demonstrate a high degree of fatty change on enhanced CT, in the pancreatic parenchyma around the area of PCIS (7). In certain patients with PCIS, focal pancreatitis with inflammatory cells, desmoplastic changes, fibrosis, and fatty changes are observed in the parenchyma around the area of PCIS (8-10). Ikeda et al classify PCIS into 3 types: flat, low papillary, and mixed (11). Based on this classification system, our patient’s disease would be classified as the low papillary type, which may tend to spread intraductally. As PCIS with intraductal spread into the main pancreatic duct and the branch duct can cause focal pancreatitis, patients may experience stenosis and dilation of the main pancreatic duct. We confirmed the presence of lymphocyte infiltration in our patient, and we believe that his stenosis was triggered by inflammation.
In Japan, the use of an oral fluoropyrimidine (S-1) is indicated for postoperative adjuvant chemotherapy in patients with pancreatic cancer (12). However, there is no evidence of the need for adjuvant chemotherapy for PCIS. More case reports are needed to determine whether adjuvant chemotherapy is indeed indicated for patients with PCIS.
As in our case, patients with both gastric cancer and pancreatic body cancer may require total gastrectomy with distal pancreatectomy, since distal gastrectomy with distal pancreatectomy may leave the patient with venous stasis and insufficient arterial perfusion to the remnant stomach. On the other hand, spleen preserving distal pancreatectomy with conservation of the splenic artery and vein for a pancreatic benign or low grade malignant tumor has accepted (13). Based on a review of the PubMed database, no case of synchronous gastric cancer and PCIS. More case reports are needed to determine whether the extent of lymph node dissection can be safely reduced for advantage of nutrition.