Standardized grossing protocol is useful for the pathology reporting of malignant neoplasms other than adenocarcinomas

Abstract

Background: There is no universally accepted protocol for gross examination of pancreaticoduodenectomy specimens. Standardized protocol (SP), known as Leeds Pathology Protocol, was previously validated in pancreatic adenocarcinoma. In this study we aimed to assess usefulness of SP in a series of specimens with pancreatic, ampullary, and duodenal malignant neoplasms other than adenocarcinomas. Materials and methods: SP was based on multi-colour inking and serial slicing of the specimens in a plane perpendicular to the duodenal axis. SP was used in a prospective cohort of 35 neoplasms of neuroendocrine, acinar, and solidpseudopapillary lineage (SP cohort). Surgical margin status, primary tumour stage, and lymph node yield in SP group were compared with corresponding data of a historical cohort of 19 cases examined using nonstandardized protocol (NSP). Samples examined in NSP and SP cohorts were comparable in terms of basic clinical characteristics, median tumour diameter, and distribution of histopathological diagnostic categories. Results: In SP cohort we noticed: (1) higher rate of detection of tumour tissue at surgical margins, (2) more frequent peripancreatic fat tissue invasion, (3) higher percentage of perineural invasion, (4) larger number of lymph nodes retrieved from the specimen, in comparison to NSP group. Application of SP was associated with significantly higher number of tissue blocks taken for histology. Conclusions: SP can be successfully applied for macroscopical examination of pancreaticoduodenectomy specimens with malignant pancreatic, ampullary, and duodenal neoplasms other than adenocarcinomas. SP with proper microscopical diagnosis enables an appropriate schedule of patients with these neoplasms to adjuvant therapy and surveillance programmes.