Significance of epidermal growth factor receptor and c-erbB-2 protein expression in transitional cell cancer of the upper urinary tract for tumour recurrence at the urinary bladder.

An immunohistochemical study of the expression of epidermal growth factor receptor (EGFR) and c-erbB-2 protein was performed in fresh-frozen sections from 30 patients with transitional cell cancers (TCCs) of the upper urinary tract (15 renal pelvic cancers, 15 ureteral cancers) who underwent total nephroureterectomy. We followed them and examined whether TCC appeared in the urinary bladder. The follow-up period ranged from 116 to 2348 days (mean 666 days). The mean period until a secondary urinary bladder cancer appeared was 306 days (116-829 days). Thirteen of those 30 TCCs (43.3%) showed increased expression of EGFR, and 11 TCCs (36.7%) showed increased expression of c-erbB-2. In 12 of 30 patients (40.0%), a secondary urinary bladder cancer appeared after surgery. In only one of the ten patients (10.0%) whose tumours did not exhibit increased expression of either of these receptors the tumour recurred in bladder. On the other hand, in 11 of 20 (55.0%) patients whose tumours had increased EGFR and/or c-erbB-2 expression, secondary urinary bladder cancers recurred after surgery (P < 0.05). Thus, the recurrence rate of TCCs with increased EGFR and/or c-erbB-2 expression was significantly higher than that of tumours showing no increased expression of these receptors (P < 0.01). These results suggest that the immunohistochemical detection of the expression of EGFR and c-erbB-2 in urothelial cancers of the upper urinary tract might be a useful method for determining the likelihood of secondary bladder cancer recurrences.