title: Correlation of CEA but not CA 19-9 as serum biomarkers of disease activity in a case of metastatic rectal adenocarcinoma.
abstract: We present the case of a 62-year-old-man with moderately differentiated adenocarcinoma of the rectum. This patient underwent neoadjuvant chemoradiation and surgical resection followed by adjuvant chemotherapy. After completing therapy, this patient had 2 instances of CEA elevation, both of which preceded the discovery of recurrent disease. While on treatment for these recurrences, CA 19-9 increased rapidly to 4,405. This CA 19-9 elevation persisted for approximately 4 months in the absence of clinical, radiographic or additional serologic evidence of progressive disease before returning to baseline. Shortly after this tumor marker normalized, a small area of locally recurrent disease was discovered. This case highlights the utility and pitfalls of colorectal cancer disease monitoring with CEA and CA 19-9. The differential diagnosis of CA 19-9 elevation is discussed in this report.
authors.affiliation: a Pennsylvania State College of Medicine ; Pennsylvania State Hershey Cancer Institute ; Hershey , PA USA.
authors.forename: Eric I
authors.initials: EI
authors.lastname: Marks
authors.forename: Matthew
authors.initials: M
authors.lastname: Brennan
authors.forename: Wafik S
authors.initials: WS
authors.lastname: El-Deiry
mesh_terms: D000230:Adenocarcinoma / Q000097:blood* / Q000473:pathology / Q000628:therapy; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000097:blood*; D018395:CA-19-9 Antigen / Q000097:blood*; D002272:Carcinoembryonic Antigen / Q000097:blood*; D005472:Fluorouracil / Q000627:therapeutic use; D006801:Humans; D002955:Leucovorin / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009944:Organoplatinum Compounds / Q000627:therapeutic use; D016634:Radiosurgery; D012004:Rectal Neoplasms / Q000097:blood* / Q000473:pathology / Q000628:therapy
chemical_list: D014408:Biomarkers, Tumor; D018395:CA-19-9 Antigen; D002272:Carcinoembryonic Antigen; D009944:Organoplatinum Compounds; D002955:Leucovorin; D005472:Fluorouracil
keywords: CA 19-9; CEA; metastatic colorectal adenocarcinoma; tumor marker