case_images: PMC11780275_01
case_images: H&E stain of abdominal mass: The tumor is growing in sheets and large nodules, with intervening fibrous bands, and a few scattered cystic/pseudoglandular structures. The overall cytomorphology is somewhat monotonous, with scattered large pleomorphic cells. Tumor cells show minimal to moderate eosinophilic to clear cytoplasm. Overt cytoplasmic mucin is not seen. Chromatin patterns range from slightly open, with small punctate nucleoli, to hyperchromatic and smudgy. Single-cell necrosis is scattered throughout. Mitotic figures are readily identifiable. These features are non-specific, and, on their own merit, do not raise the possibility of mucoepidermoid carcinoma. Only post hoc knowledge of the patient's prior diagnosis led to the correct diagnosis of this metastatic deposit.
case_images: TCA-16-e70001-g003.jpg
case_images: PMC11780275_01_TCA-16-e70001-g003.jpg
case_images: tca70001-fig-0001
case_images: The pathology result was compatible with adenosquamous carcinoma with pericardium and large vessel invasion (Figure 1).
case_images: (A) Cytokeratin AE1/AE3 immunostain of abdominal mass: Diffuse strong positive in all tumor cells. (B) p53 Immunostain of abdominal mass: Aberrant overexpression pattern, typically correlating to an underlying TP53 abnormality. (C) p63 Immunostain of abdominal mass: Diffuse strong nuclear positivity in all tumor cells.
case_images: TCA-16-e70001-g001.jpg
case_images: PMC11780275_01_TCA-16-e70001-g001.jpg
case_images: tca70001-fig-0002
case_images: Immunohistochemistry (IHC) stains were positive for p63, p40, CD117, and CD5 but negative for PAX8 and ER, which was not matched to the IHC stain of the previous endometrioid adenocarcinoma (Figure 2A-C).