Collision tumor of the rectum: a case report of metastatic gastric adenocarcinoma plus primary rectal adenocarcinoma.
Collision tumors are thought to arise from the accidental meeting and interpenetration of two independent tumors. We report here a highly unusual case of a 61-year old man who had a unique tumor that was composed of a metastatic adenocarcinoma from the stomach to the rectum, which harbored a collision tumor of primary rectal adenocarcinoma. The clonalities of the two histologically distinct lesions of the rectal mass were confirmed by immunohistochemical and molecular analysis. Although histologic examination is the cornerstone in pathology, immunohistochemical and molecular analysis can provide evidence regarding whether tumors originate from the same clone or different clones. To the best of our knowledge, this is the first reported case of such an occurrence.
Roh
Young-Hoon
YH
Department of Pathology, Dong-A University College of Medicine 1, 3-ga, Dongdaeshin-dong, Seo-gu, Busan 602-715, Korea. msroh@dau.ac.kr.
Lee
Hyoun-Wook
HW
Kim
Min-Chan
MC
Lee
Kyeong-Woo
KW
Roh
Mee-Sook
MS
D000230:Adenocarcinoma / Q000235:genetics / Q000473:pathology* / Q000556:secondary*; D042822:Genomic Instability; D006801:Humans; D019656:Loss of Heterozygosity; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary; D012004:Rectal Neoplasms / Q000235:genetics / Q000473:pathology* / Q000556:secondary*; D013274:Stomach Neoplasms / Q000235:genetics / Q000473:pathology*