title: Pathological features of renal cell carcinoma incidentally discovered at autopsy.
abstract: Renal cell carcinomas incidentally discovered at autopsy (IRCs) were retrospectively analyzed to determine whether they had any pathological features differing from clinical renal cell carcinomas (CRCs): From 7,970 autopsy cases, there were 51 cases (0.65%) of renal cell carcinoma (RC) including 42 men and 9 women (ratio 4.6:1). The mean age of RC cases was 66.3 +/- 12.9 (range of 20 to 91 years). Of the 51 RC cases, approximately half of them (25/51) were IRC cases. No difference was shown in age and sex between IRC and CRC cases. Mean tumor size of IRC was 2.6 +/- 2.5 cm in diameter. This was significantly smaller (P less than 0.01) than that of CRC (7.3 +/- 2.8 cm). Histologically, both grade 1 and clear cell type were significantly more predominant among IRC cases than CRC cases (P less than 0.01 and P less than 0.05, respectively). Only one out of 25 cases of IRC had distant metastasis, as compared to 23 out of 26 CRC cases (88.5%). These pathological features indicate that the incidentally discovered renal cell carcinoma may have less malignant potential than clinical tumors. Unexpectedly, the majority of the IRC cases (88.0%) were associated with advanced neoplasia of other sites, as compared to only 19.0% of CRC cases (P less than 0.01).
authors.affiliation: Second Department of Pathology, Mie University School of Medicine, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kihira
authors.forename: T
authors.initials: T
authors.lastname: Shiraishi
authors.forename: R
authors.initials: R
authors.lastname: Yatani
authors.forename: I
authors.initials: I
authors.lastname: Roa
authors.forename: P I
authors.initials: PI
authors.lastname: Liu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001344:Autopsy; D002292:Carcinoma, Renal Cell / Q000453:epidemiology / Q000473:pathology* / Q000556:secondary; D005260:Female; D006470:Hemorrhage / Q000209:etiology; D006801:Humans; D015994:Incidence; D007680:Kidney Neoplasms / Q000453:epidemiology / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009336:Necrosis; D009378:Neoplasms, Multiple Primary / Q000473:pathology; D012189:Retrospective Studies