NANETS2023 Basic Science (28 abstracts)
1Department of Surgery, University of Alabama at Birmingham, Birmingham, AL; 2Department of Pathology, University of Alabama at Birmingham, Birmingham, AL; 3Department of Biology, Tuskegee University, Tuskegee, AL
Background: Following IHC of CALR, H-scoring was performed by a pathologist. H-scoring was validated by MIF of the same tissue, wherein random-forest machine learning (ML) classifiers were employed to classify cells. ML classifiers were trained to distinguish between pNET cells and tumor stroma using approximately 30% of cells for the respective cell population of interest in each TMA core. Pearsons correlations were used to evaluate the relationship between H-scoring and mean fluorescent intensity in tumor cells. H-scoring was then evaluated for a relationship with clinical variables, including tumor grade and metastatic status (both lymphatic and distant). 111 resected pNET samples were analyzed.
Methods: CALR MIF was performed for 40/89 patients. CALR H-scoring and IF were highly correlated (r= 71 [95% CI 50-83]; p < 0.0001). CALR expression was significantly higher in pNETs compared to normal pancreatic islets (p < 0.0001), as well as in primary pNETs compared to distant metastatic pNETs (P =0.02). There was however no difference in CALR expression based on tumor grade (0.82) or N stage (0.58).
Results: CALR MIF was performed for 40/111 patients. CALR H-scoring and IF were highly correlated (r= 71 [95% CI 50-83]; p < 0.0001). CALR expression differed significantly between pNETs and normal pancreatic islets (p < 0.0001), approached significance by N stage (P =0.07), but did not differ by M stage (P =0.72) or tumor grade (P =0.78).
CALR H Score (mean ± sd) | p value | |||
Tumor/Islet | Tumor (n =111) 217±95 | Islet(n =17) 53±51 | < 0.0001* | |
Grade | G1 (n =51) 213±101 | G2 (n =52) 218±92 | G3 (n =6) 241±73 | 0.82 |
M Stage | M0 (n =63) 232±86 | M1 (n =38) 186±105 | Mx (n =10) | 0.02* |
N Stage | N0 (n =62) 219±96 | N1 (n =26) 232±85 | Nx (n =23) | 0.58 |
Conclusion: CALR expression is increased in pNETs compared to normal islets and may be decreased in cases of distant metastatic disease. Future studies will aim to examine these relationships in a larger cohort with more diverse clinical outcome to better define this relationship.
Abstract ID 23717