RESUMO
Autoimmune pancreatitis (AIP) has attracted much attention in the last two decades, and due to the diagnostic value of immunoglobulin G4 (IgG4), the number of cases diagnosed in clinical practice has markedly increased. However, in contrast to prototypic IgG4-related type 1 AIP, a minor subtype of AIP, referred to as type 2 AIP, is less widely known and has thus not yet been characterized in detail. Type 2 AIP is unrelated to IgG4 and is a completely distinct entity from type 1 AIP. One confusing factor is that the two types of AIP share patterns of clinical presentation (e.g., acute pancreatitis and painless jaundice) and imaging abnormalities (e.g., diffuse or segmental enlargement). Since there are currently no established serum markers, the diagnosis of type 2 AIP is highly challenging and requires the tissue confirmation of neutrophilic injury to the pancreatic ducts, a finding designated as a granulocytic epithelial lesion. Approximately one-third of cases are associated with inflammatory bowel disease, particularly ulcerative colitis; however, the pathological relationship between these two conditions has not yet been clarified. Unanswered questions relate to its pathophysiology, the potential development of a similar granulocytic injury in other organs, and the characteristics of pediatric cases. This review summarizes consensus and controversies surrounding type 2 AIP, with the aim of increasing awareness and highlighting the unmet needs of this underrecognized condition.
RESUMO
BACKGROUND: We propose a new classification for the location of gastric cancer - the PTD classification (i.e., zones P, T, and D; see below), with the zones classified according to the physiological lymphatic flow. METHODS: Three hundred and thirty-six patients with T1 or small T2 gastric cancer who underwent sentinel node mapping at our hospital were enrolled. The relationship between the location of the gastric cancer and the physiological lymphatic flow derived from sentinel node mapping was investigated. Lymphatic basins were defined as lymphatic zones divided by the stream of stained lymphatic canals. RESULTS: One hundred and forty-six patients underwent standard gastrectomy with more than D2 dissection and the other 190 patients underwent function-preserving gastrectomy with the omission of lymph node dissection outside the lymphatic basin. In the former group, the progression pattern of lymph node metastasis was observed; nodal metastasis occurred in sentinel nodes first, and rarely extended outside the lymphatic basin. In the latter group, none of the patients have had a recurrence. The PTD classification we propose is as follows: the dividing line between the proximal region (zone P) and the transitional region (zone T) is the line that links the point of the watershed between the left gastroepiploic artery and right gastroepiploic artery, to the point that is the inflow point of the first descending branch of the left gastric artery; and the dividing line between zone T and the distal region (zone D) is an arc at a radius of 8 cm from the pylorus. There were no lymphatic basins within the right gastric artery area for tumors located in zone T. CONCLUSION: The advantage of the PTD classification is that if the PTD classification were to be used as a guide for gastric resection procedures, preservation of the pylorus would become possible without diminishing the prognosis in patients with cT1N0 cancer located in zone T.
