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Published on: June 23, 2020
How should PCNA be assessed? Total of stained cells or only the most intensely stained ones?
C Kemp1, V N Alberti, G R de Lima
1Department of Gynecology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Brazil.
Objective:
This study aimed to analyse whether a marker of proliferative activity (PCNA) could provide a prognosis of tumor evolution and to determine whether different interpretation criteria could alter the results.
Method:
The presence of PCNA in 59 patients of state II (T2 N0.1 M0) mammary carcinoma was determined.
Result:
Numerical proportions of total and intensely stained cells were established. These data were compared with anatomopathological parameters. A significant association between higher cyclin values and worse histological and nuclear grading was encountered, particularly in patients with a "negative axilla" using the PCNA index. Cyclin values were not significant in relation to any parameters when indices from the intensely stained cells were considered exclusively.
Conclusion:
Higher nuclear (NG3) and histological (HGIII) grading, associated with a high PCNA index (> 50), distinguish high-risk patients, and it is more appropriate considering all the stained cells as representative of PCNA indices, thus reflecting tumor aggressiveness.
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