Which Is the Best Surgical Approach for the Pancreatic Cancer? A Classification of Pancreatic Cancer to Guide Operative Decisions Is Needed
We read with great interest the article by Yosuke Inoue et al 1 We recognize the important concept of systematic mesopancreas dissection (SMD), which is classified into three levels and used to guide operative decisions. The authors state that the supracolic anterior artery-first approach (SAA) was feasible in all types of patients. However, we contend that the SAA is the best way to treat all types of periampullary tumors and that the current classification of SMD is adequate to guide operative decisions.
Until now, the optimal surgical technique of pancreatic cancer has remained controversial. Hirota et al 2 introduced a no-touch technique, which has many potential advantages; however, there is high risk in patients with superior mesenteric vein/portal vein (SMV/PV) invasion or compression by the tumor. Weitz et al 3 described an artery-first approach technique (AFA), which differs from the classic resection technique. However, the AFA is more difficult and involves unnecessary dissection of the SMA in patients without SMV/PV distortion. Therefore, the most effective technique remains unidentified. The most important classification systems for pancreatic cancer are currently the Union Internationale Contre le Cancer system and the Japan Pancreas Society system, both of which are based on the TNM system. 4 However, despite the worldwide application of these systems, little information is available on their use in operative decision-making. The current absence of an adequate classification system to guide surgeons in choosing the best operative technique leads to nonvalidated, “personal” treatment regimens.
Inoue et al 1 report a new classification of SMD that is used to guide operative decisions. We agree with the defined operative extent for Level 1 tumors. However, the technique is not the best choice for some Level 1 tumors. For example, it is difficult to dissect SMV in large solid pseudopapillary tumors of the pancreatic head with SMV/PV invasion or compression classified as requiring Level 1 dissection. For these cases, the Level 3 technique may be more appropriate. Moreover, tumors with the SMV/PV invasion classified as requiring Level 2 dissection should receive the Level 3 technique. Pancreatic cancer is classified as requiring Level 3 dissection; however, if the pancreatic cancer without SMV/PV invasion or compression is a small tumor, dissecting the SMA as for Level 3 is unnecessary. The technique used for Level 1, requiring SMV dissection first, provides radical resection. Therefore, we consider that the systematic mesopancreas dissection classification adequately determines the operative extent, but not the operative technique.
We herein suggest a new classification system that guides the operative decision. Using computed tomography, we divided pancreatic carcinomas into the following 8 types (other periampullary tumors are divided into 4 types) according to whether the tumor invades or compresses the surrounding vasculature and the degree of invasion.
The aim of our classification is to expedite treatment consensus regarding the best surgical technique. For type I cancer, we recommend the SMV-first approach as Hirota et al 2 described. In our center, the SMA is lifted to the right as the preset tape is moved from the rear of the SMV to the right side. In this way, we avoid passage of a tape along the SMA, but also achieve exposure of the mesouncinate, facilitating total mesopancreas excision. For type II cancer, we reported a new technique called the “total arterial devascularization-first” technique (TADF), which is similar to the Inoue et al 1 Level 3 technique. 5 The different steps are that we first ligate the gastroduodenal artery and transect the pancreas to achieve the total arterial devascularization aim.