AgNOR count and subjective AgNOR pattern assessment (SAPA) score in carcinoma of the pancreatic head including periampullary tumors

Abstract

Context: Only a few studies are available in the literature regarding the AgNOR (argyrophilic nucleolar organizer region) count in pancreatic adenocarcinoma but studies on the SAPA (subjective AgNOR pattern assessment) score are completely lacking. Objective: We attempted to estimate the AgNOR count and the SAPA score in carcinoma of the pancreatic head including periampullary tumors and to correlate them with other various clinico-histological parameters. Setting: Patients undergoing pancreatic resection at the University Hospital, Banaras Hindu University, Varanasi, India. Patients: Twenty-four cases of carcinoma of the pancreatic head including periampullary tumors. In addition, on the resected specimen of the pancreas, the area which was normal was chosen and, in that normal tissue, the AgNOR was also studied. Main outcome measures: Patients were studied for the AgNOR count and the SAPA score, and the values were correlated with the size of the tumor, the type of tumor and histological type and grade of tumor. Results: The values of the AgNOR count and the SAPA score were significantly higher in cases of pancreatic cancer than in the healthy pancreas. The AgNOR count was 1.6±0.1 in the healthy pancreas while it was 2.8±0.5 in cases of pancreatic carcinoma (P<0.001). The SAPA score was 5.6±0.2 in the healthy pancreas while it was 8.0±1.4 in pancreatic carcinoma (P<0.001). Tumors less than or equal to 2 cm in size had an AgNOR count of 2.6±0.08 while the AgNOR count was 3.4±0.02 in tumors larger than 2 cm (P<0.001). The SAPA score was also higher in tumors greater than 2 cm in size (7.3±0.2 vs. 9.4±0.8; P<0.001). Periampullary tumors had a significantly lower (P<0.001) AgNOR count (2.7±0.06) and SAPA score (7.8±0.2) as compared to carcinoma of the head of the pancreas (AgNOR count 3.3±0.03 and SAPA score 9.2±0.7). Well-differentiated carcinomas had significantly lower AgNOR counts as compared to other tumors except acinar cell carcinomas since acinar cell carcinomas are also well-differentiated tumors. The SAPA score was also higher in moderately-differentiated tumors and the difference between moderately-differentiated tumor and other types of tumors was significant although there was no significant difference between cystadenocarcinomas and unclassified tumors, and between acinar cell carcinomas and well-differentiated tumors on SAPA scoring. Conclusions: The values of the AgNOR count and the SAPA score are well-correlated with the size of the tumor, the type of tumor and the histological grade.