Departments of *Pathology ‡General Surgery §Surgical Oncology, Emory University School of Medicine and Winship Cancer Institute ∥Department of Pathology, Piedmont Hospital, Atlanta, GA †Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY Departments of ¶Pathology #General Surgery, Wayne State University and Karmanos Cancer Institute, Detroit, MI.
Am J Surg Pathol. 2014 Apr;38(4):480-93. doi: 10.1097/PAS.0000000000000165.
Pancreaticoduodenectomy (PD) specimens present a challenge for surgical pathologists because of the relative rarity of these specimens, combined with the anatomic complexity. Here, we describe our experience on the orientation, dissection, and sampling of PD specimens for a more practical and accurate evaluation of pancreatic, distal common bile duct (CBD), and ampullary tumors. For orientation of PDs, identification of the "trapezoid," created by the vascular bed at the center, the pancreatic neck margin on the left, and the uncinate margin on the right, is of outmost importance in finding all the pertinent margins of the specimen including the CBD, which is located at the upper right edge of this trapezoid. After orientation, all the margins can be sampled. We submit the uncinate margin entirely as a perpendicular inked margin because this adipose tissue-rich area often reveals subtle satellite carcinomas that are grossly invisible, and, with this approach, the number of R1 resections has doubled in our experience. Then, to ensure proper identification of all lymph nodes (LNs), we utilize the orange-peeling approach, in which the soft tissue surrounding the pancreatic head is shaved off in 7 arbitrarily defined regions, which also serve as shaved samples of the so-called "peripancreatic soft tissue" that defines pT3 in the current American Joint Committee on Cancer TNM. With this approach, our LN count increased from 6 to 14 and LN positivity rate from 50% to 73%. In addition, in 90% of pancreatic ductal adenocarcinomas there are grossly undetected microfoci of carcinoma. For determination of the primary site and the extent of the tumor, we believe bisectioning of the pancreatic head, instead of axial (transverse) slicing, is the most revealing approach. In addition, documentation of the findings in the duodenal surface of the ampulla is crucial for ampullary carcinomas and their recent site-specific categorization into 4 categories. Therefore, we probe both the CBD and the pancreatic duct from distal to the ampulla and cut the pancreatic head to the ampulla at a plane that goes through both ducts. Then, we sample the bisected pancreatic head depending on the findings of the case. For example, for proper staging of ampullary carcinomas, it is imperative to take the sections perpendicular to the duodenal serosa at the "groove" area, as ampullary carcinomas often extend to this region. Amputative (axial) sectioning of the ampulla, although good for documentation of the peri-Oddi spread of the intra-ampullary tumors, unfortunately disallows documentation of mucosal spread of the papilla of Vater tumors (those arising from the edge of the ampulla, where the ducts transition to duodenal mucosa and extending) into the neighboring duodenum. Axial sectioning also often fails to document tumor spread to the "groove" area. In conclusion, knowledge of the gross characteristics of the anatomic hallmarks is essential for proper dissection of PD specimens. The approach described above allows practical and accurate documentation and staging of pancreas, distal CBD, and ampullary cancers.
胰十二指肠切除术（PD）标本对外科病理学家来说是一个挑战，因为这些标本相对较少见，加上解剖结构复杂。在这里，我们描述了我们在 PD 标本定向、解剖和取样方面的经验，以便更实际和准确地评估胰腺、远端胆总管（CBD）和壶腹肿瘤。为了对 PD 进行定向，识别由中心血管床、左侧胰颈边缘和右侧钩突边缘形成的“梯形”至关重要，因为这样可以找到标本的所有相关边缘，包括位于该梯形右上边缘的 CBD。定向后，可以对所有边缘进行取样。我们将整个钩突边缘作为垂直墨缘送检，因为这个富含脂肪的区域经常会发现肉眼看不见的微小卫星癌，采用这种方法，我们的 R1 切除率增加了一倍。然后，为了确保正确识别所有淋巴结（LN），我们采用了橙皮样方法，其中胰头周围的软组织被刮除 7 个任意定义的区域，这些区域也作为所谓的“胰周软组织”的刮取样本，该组织定义了当前美国癌症联合委员会 TNM 分期中的 pT3。采用这种方法，我们的淋巴结计数从 6 增加到 14，淋巴结阳性率从 50%增加到 73%。此外，在 90%的胰腺导管腺癌中，有肉眼无法检测到的癌微灶。为了确定原发部位和肿瘤范围，我们认为胰头的横断（矢状）切片不如横断（水平）切片有揭示性。此外，记录壶腹十二指肠面的发现对于壶腹癌及其最近的特定部位分类为 4 个类别至关重要。因此，我们从远端向壶腹探查 CBD 和胰管，并在穿过两条管道的平面上将胰头横断至壶腹。然后，根据病例的发现对横断的胰头进行取样。例如，对于正确分期壶腹癌，必须在“凹槽”区域取垂直于十二指肠浆膜的切片，因为壶腹癌通常延伸到该区域。尽管壶腹的轴向（冠状）切片有利于记录胰管内肿瘤在Oddi 周围的扩散，但不幸的是，它不能记录 Vater 乳头肿瘤（起源于壶腹边缘，即胆管过渡到十二指肠黏膜的部位，并向相邻的十二指肠延伸）的黏膜扩散。轴向切片也经常不能记录肿瘤向“凹槽”区域的扩散。总之，了解解剖标志的大体特征对于 PD 标本的正确解剖至关重要。上述方法允许对胰腺、远端 CBD 和壶腹癌进行实际和准确的记录和分期。
