Immunohistochemically, the adenocarcinomas were positive for CK7 (4/4), CEA (4/4), MUC6 (3/3), PAX8 (3/4), CK20 (2/4), CDX2 (2/4), and estrogen receptor (1/4).
Biopsy findings revealed a moderately differentiated adenocarcinoma with immunohistochemical profile supporting prostate as the primary tumor site: negative for cytokeratin-7 and cytokeratin-20 and positive for prostate-specific antigen, prostate-specific acid phosphatase, and alpha-methylacyl-CoA-racemase.
The tumor cells were positive for CDX-2 and cytokeratin 20 and negative for cytokeratin 7 and thyroid transcription factor-1, consistent with an enteric/colonic-type adenocarcinoma, demonstrating progressive atypia and malignancy.
After 12 mo of treatment with icotinib, ovarian biopsy showed adenocarcinoma with CDX2(-), TTF-1(+++), PAX8(-), CK-7(+++), CK-20(++), and Ki67(15%+), accompanied with EGFR 19-del mutation and T790M mutation.
Moreover, immunohistochemical staining of the tissue specimen for thyroid transcription factor 1, cytokeratin 7 (CK7), and CK20 and CT-guided gun biopsy of the lung mass confirmed the presence of an adenocarcinoma that originated from the lung.
Immunohistochemically, the adenocarcinomas were positive for MUC6 (4/5), PAX8 (3/5), CK7 (5/5), CK20 (1/5), CDX2 (5/5), CA19.9 (5/5), CEA (4/5), CA125 (5/5), and hepatocyte nuclear factor 1β (5/5). p16, estrogen receptor, and Napsin A were negative in all cases tested, whereas p53 exhibited mutation-type staining in 3/5 cases.
The aim of this study was to explore a new intestinal marker, SATB2, in conjunction with CDX2 and CK20 in differential diagnosis of sinonasal adenocarcinomas.
Factors related with shorter overall survival was adenocarcinoma histology (<i>P</i>=0.001), increased CA19-9 (<i>P</i>=0.003), increased CEA (<i>P</i>=0.047), increased LDH (<i>P</i><0.001), CK20 positivity (<i>P</i>=0.002), presence of bone metastasis (<i>P</i>=0.017), metastasis not confined to the lymph nodes (<i>P=</i>0.015), unfavorable clinical group based predefined category (<i>P</i>=0.017), and patients with no treatment (<i>P</i><0.001).
Histopathological and immunohistochemical examination revealed a well-differentiated adenocarcinoma (strongly positive staining for cytokeratin 20 and CDX2), pT3N0 stage IIA.
Twenty-five previously reported cases, classified as mucinous adenocarcinoma and adenocarcinoma, not otherwise specified, also had similar characteristics to enteric-type adenocarcinoma and generally expressed CK20, CDX2, CEA, and/or MUC2.Some of these cases had a thymic cyst.
Comparison of spheroids with the original tumour revealed that spheroid culture generally preserved adenocarcinoma histology and expression patterns of cytokeratin 20 and carcinoembryonic antigen.
As was expected, CK7 expression was documented in all 9 PEACs and 20 tPCAs while CK20 was significantly more prevalent in adenocarcinoma that originated from colorectal.
Regarding MSI, in case with no BRAF mutations, a progressive decrease in CK20 expression was noted, and in BRAF-mutated adenocarcinomas, no expression of CK20 was observed.
Immunohistochemically, the adenocarcinoma strongly stained for cytokeratin 20 and carcinoembryonic antigen, while the endocrine component displayed a dot-like positivity for pan-cytokeratins and chromogranin.
Therefore, we evaluated the combined immunohistochemical expression of CK7 and CK20 on paraffin-embedded material of 214 resection specimens for adenocarcinoma, comprising 66 esophageal, 73 cardiac and 75 distal gastric adenocarcinomas (UICC-classification).
This report directly compares CK20 mRNA and protein expression in serial sections of archival, formalin-fixed, paraffin-embedded (FFPE) colorectal adenocarcinomas.
In gastrointestinal carcinomas similarly examined, CK 20 has been detected in almost all cases (50/52) of colorectal adenocarcinomas, including all grades of differentiation and malignancy and also metastatic tumors, whereas CK 20 immunostaining in gastric carcinomas has been found less consistent and more heterogeneous.