title: Prognostic value of nuclear area index in combination with the World Health Organization grading system for patients with renal cell carcinoma.
abstract: OBJECTIVE
  To assess the diagnostic accuracy of the World Health Organization (WHO) grading system for renal cell carcinoma (RCC) in terms of nuclear size evaluation. Furthermore, the prognostic usefulness of the nuclear area index (NAI), a new nuclear morphometric parameter expressed as the mean nuclear area (MNA) ratio of cancer to normal tubular cells, is investigated.
  
  
  METHODS
  Measurement of the nuclear areas of cancer and normal tubular cells was performed on the histologic slides from the 76 patients with RCC, and the distribution of MNA and NAI was compared among the WHO grades. The clinical usefulness of MNA, NAI, grade, and TNM categories for the prediction of the progression-free and cause-specific survival of the patients was examined.
  
  
  RESULTS
  MNA for cancer cells and NAI significantly increased according to the grade. NAI was 1.0 or less in 9 of the 10 patients with G1 tumors and more than 1.0 in 12 of the 13 patients with G3 tumors, whereas the NAI ranged widely from 0.53 to 2.0 in 53 patients with G2 tumors. By multivariate analysis, including grade and TNM categories, NAI and MNA were independent variables for survival in all the patients as well as for cancer progression in localized disease.
  
  
  CONCLUSIONS
  WHO G2 RCCs are actually composed of tumors with varying nuclear size, and the prognosis of the patients with G2 tumors varied as well. NAI could provide improved prognostic information for the patients with RCC, especially in G2 cases.
authors.affiliation: Department of Urology, Fukui Medical University, Fukui, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kanamaru
authors.forename: H
authors.initials: H
authors.lastname: Akino
authors.forename: Y
authors.initials: Y
authors.lastname: Suzuki
authors.forename: S
authors.initials: S
authors.lastname: Noriki
authors.forename: K
authors.initials: K
authors.lastname: Okada
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D002292:Carcinoma, Renal Cell / Q000401:mortality / Q000473:pathology*; D005500:Follow-Up Studies; D006801:Humans; D007680:Kidney Neoplasms / Q000401:mortality / Q000473:pathology*; D007684:Kidney Tubules / Q000166:cytology; D008875:Middle Aged; D011379:Prognosis; D016019:Survival Analysis; D014944:World Health Organization