Prognostic value of flow cytometry in carcinoma of the kidney
Article published in Urologia Polska 2004/57/3.

authors

Janusz Dembowski ¹, Michał Wróbel ¹, Anna Kołodziej ¹, Danuta Duś ², Bartosz Małkiewicz ¹, Jarosław Kasprzak ¹, Krzysztof Dudek ³

¹ Katedra i Klinika Urologii Akademii Medycznej we Wrocławiu
² Instytut Immunologii PAN we Wrocławiu
³ Politechnika Wrocławska, Instytut Konstrukcji i Eksploatacji Maszyn

keywords

kidney, renal cancer, DNA content, S Phase Fraction, Proliferating Phase Fraction

summary

introduction

Renal cancer remains a diagnostic and therapeutic problem in view of distant metastases, even in cases of small tumours (T1T2) and primary disease (N0M0). Finding additional prognostic factors is necessary to apply earlier adjuvant immunotherapy. One of such factors can be DNA content in the neoplasmatic cell nucleus, different from that in the normal cell. Poor prognosis depends also on other parameters as S-Phase Fraction (SPF) and Proliferating Phase Fraction (PPF) which reveal mitotic activity of the cell. The present paper was aimed at determining the prognostic value of DNA ploidy, S-phase fraction and proliferating phase fraction, as compared with classical factors - tumour staging T and its malignancy (grading, G).

material and methods

51 patients underwent surgery for renal cancer N0M0. They were divided into group I - with no metastases, and group II - where metastases appeared during follow up for 18 to 36 months. Three prospective operative specimen were taken and stored at -22oC. Samples were stained with propinium iodide and evaluated in a flow cytometer (FACSCalibur, Beckton-Dickinson). Ploidy was compared to a standard lymphocyte suspension. Statistical analysis was performed by Fisher's exact test (comparison of aneuploidy frequency) and UMann-Whitney test (comparing S-Phase and Proliferating Phase fractions). Calculations were performed with support of STATISTICA v.6.0 software (StatSoft).

results

The incidence of aneuploidy in Fisher's test was 23,5 percent - 15 and 54,5 percent in groups I and II, respectively (p<0,05). Average S-phase fraction in UMann-Whitney test was 9,9 percent - 8,5 and 14.9 percent in groups I and II, respectively (p<0,01). The proliferating fraction in UMann-Whitney test was 15 percent - 12,7 and 23,2 percent in groups I and ii, respectively (p<0,001. The highest sensitivity (81,8 percent) in predicting metastases formation had T>2 stage of the tumour and SPF >11 percent. The other factors (nuclear grade, aneuploidy, PPF and SPF) did not reveal higher sensitivity alone nor in combination. The highest specificity (94,9 percent) - at a low sensitivity - was produced by combination of T, nuclear grade and aneuploidy. SPF over 11 percent was connected with highest negative prognostic value (93,1 percent). Highest positive prognostic value was obtained by aneuplody combined with tumour stage T.

conclusions

Aneuploidy in combination with T>2 is connected with 66,7 percent probability of progression in patients with primary N0M0 tumour. This group of patients should be subjected to an particularly accurate follow-up and - perhaps - adjuvant immunotherapy. Such intensive control is not needed for patients with low SPF.