title: Expression of CD7, CD20 and CDX-2 in a secondary signet-ring cell tumor of the prostate: a case report.
abstract: As is well-known, signet ring cell carcinoma (SRCC) rarely appears as a histological finding in the prostatic tissue. Nevertheless, a differentiation should be made between a primary tumor and a metastatic disease. We describe the case of a 52-year-old man with lower urinary tract symptoms, serum total PSA of 0.2 ng/ml, elevated serum CEA and CA19-9 levels. Two years prior to presentation, he underwent total gastrectomy with histological findings indicating poor differentiated adenocarcinoma with signet-ring cell. A palpable nodule was found on digital rectal examination and for this reason he underwent 12-core transperineal prostate biopsy with a diagnosis of poor differentiated adenocarcinoma with signet-ring cell and adipose tissue infiltration. Immunohistochemical examinations revealed positivity for PAS, CK7 and CDX-2, focal positivity for CK20 and negativity for PSA and PSAP. The diagnosis of a prostatic secondary SRCC was possible given the positivity to CK7, CDX-2, focal positivity to CK20 and negativity to PSA.
authors.forename: S
authors.initials: S
authors.lastname: Cimino
authors.forename: G I
authors.initials: GI
authors.lastname: Russo
authors.forename: V
authors.initials: V
authors.lastname: Favilla
authors.forename: E
authors.initials: E
authors.lastname: Fragala
authors.forename: Z
authors.initials: Z
authors.lastname: Collura
authors.forename: A
authors.initials: A
authors.lastname: Zanghi
authors.forename: T
authors.initials: T
authors.lastname: Castelli
authors.forename: M
authors.initials: M
authors.lastname: Madonia
authors.forename: G
authors.initials: G
authors.lastname: Morgia
mesh_terms: D018951:Antigens, CD20 / Q000378:metabolism*; D019011:Antigens, CD7 / Q000378:metabolism*; D000071616:CDX2 Transcription Factor; D018279:Carcinoma, Signet Ring Cell / Q000378:metabolism* / Q000556:secondary; D018398:Homeodomain Proteins / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000556:secondary; D013274:Stomach Neoplasms / Q000473:pathology; D015534:Trans-Activators / Q000378:metabolism*
chemical_list: D018951:Antigens, CD20; D019011:Antigens, CD7; D000071616:CDX2 Transcription Factor; D018398:Homeodomain Proteins; D015534:Trans-Activators