Table 2 Mucinous borderline tumor (MBOT) and mucinous carcinoma (MOC) cases from the Genomic Analysis of Mucinous Tumors (GAMuT) cohort with discrepancies between p53 immunohistochemistry (IHC) and TP53 mutation status by sequencing.
Case | Tumor type | Detected mutation | AF | Method | IHC result | IHC source | Possible explanations |
|---|---|---|---|---|---|---|---|
C1454 | MBOT | p.V216L | 0.31 | SureSelect panel | Normal | TMA (then full) | IARC: missense Clinvar: likely pathogenic False negative normal IHC |
C1961 | MOC | p.Q375* | 0.37 | SureSelect panel | Normal | TMA (then full) | Late truncating mutation expressing nonfunctional protein as false negative normal IHC |
C1981 | MOC | p.R156H | 0.36 | SureSelect panel | Normal | TMA (then full) | IARC: missence Clinvar: VUS |
15404 | MOC | NMD | NA | Exome | Abnormal OE90 | Full | Clear IHC signal: suboptimal sequencing, mutation in something other than p53 that influences p53 expression |
VOA3937 | MOC | NMD | NA | Exome | Abnormal OE90 | Full | Clear IHC signal: suboptimal sequencing, mutation in something other than p53 that influences p53 expression |
WM1070 | MOC | NMD | NA | Exome (unpaired) | Abnormal OE70 (MOC) normal (MBOT) | Full | False positive IHC; tumor heterogeneity |
C885 | MOC | NMD | NA | SureSelect panel | Abnormal CA100 | TMA (then full) | Clear IHC signal: false negative sequencing, undetected large deletion |
