[Detection of circulating tumor cells from peripheral blood in patients with transitional cell carcinoma--pilot study. Comparison with the standard histopathological staging].

BACKGROUNDS

The aim of this pilot study was to investigate whether UP-II and EGFR genes expression detection with RT-PCR and the use of immunohistochemistry methods on patient samples taken before and after surgery could be used as a cancer marker for detection of circulating tumor cells in peripheral blood of patients with TCC. Another goal of this study was to identify whether surgery can influence the amount of circulating tumor cells and to correlate the samples with standard histopathological staging.

MATERIALS AND METHODS

A total of 43 patients with histologically provenTTC was enrolled in the study. There were 33 men and 10 women in the sample, mean age was 65 +/- 12 years (range 37-85 years). Forty (93.0%) patients had TCC of the urinary bladder, 2 (4.6%) had TCC of renal pelvis and 1 (2.3%) had TCC of urinary bladder, urethra, and renal pelvis. A sample of 10 ml of peripheral blood was collected from each patient before and within 1 hour after a surgery. Blood samples were used for immunomagnetic separation of circulating tumor cells and determination of UP-II and EGFR genes expression. Subsequently, cancer tissue was processed, endolymphatic, intravascular and peritoneal invasion determined and CK-7, CK-20, stromelysin, Ki-67 and p53 expression evaluated. Blood samples taken before and after the surgery were also subjected to immunohistochemical analysis using hematoxylin-eosin (HE) staining and staining by Papanicolaus (PAP). CK-7 and CK-20 expression was also evaluated.

RESULTS

EGFR and UP-II were expressed in 24 of the 35 (68.6%) and in 19 of the 35 (54.3%) cancer tissues samples, respectively. EGFR was expressed neither in blood samples nor in immuno-separated cell samples. UP-II was expressed in 1 of the 19 (5.3%) samples of immuno-separated cells acquired before the surgery and in no sample of immuno-separated cells obtained after the surgery (P < 0.9999). Moreover, UP-II was expressed in 2 of the 32 (6.3%) whole blood samples taken before the surgery and in 3 out of 32 (9.4%) whole blood samples taken within an hour after the surgery (P < 0.9999). Histopathological examination showed TCC invasion in 11 of the 43 patients: 1 patient with intravascular, 6 with endolymphatic, 1 with intravascular and endolymphatic and 3 with intravascular, endolymphatic and perineural invasion. Immunohistochemical examination of separated blood before and after the surgery by PAP and HE staining, CK-7 and CK-20 expression were negative in nearly all samples. Immunohistochemical examination ofTCC tissue showed positive results in 97.7% for CK-7expression, 74.4% for CK-20 and 97.7% for stromelysin. Cytological examination of urine was positive in 19 (50%) patients and correlated well with higher grade G3 in 20 (46.5%) patients. Ki-67 expression was significantly higher in patients with G3 (31.15%) in comparison to patients with G1 (7.53%) (p < 0.01). There was no significant association between grade and expression of p53 and stromelysin in cancer tissue.

CONCLUSION

Our preliminary tests did not show any significant change to EGFR and UP-II expression in peripheral blood and in immuno-separated cells before and after a surgery. The results for a group of patients with lower pTNM grade did not confirm the presence of malignant urothelial cells in peripheral blood.