Distant metastasis from bilharzial bladder cancer.

BACKGROUND

Distant metastasis is rarely described among bilharzial bladder cancer patients. However, with improved 5-year survival rates following adjuvant local therapy, distant metastasis is now reported with increasing frequency.

METHODS

Three-hundred-fifty-seven bilharzial bladder cancer patients were treated at the National Cancer Institute in Cairo, Egypt, during the period 1981-1990. They were treated with either cystectomy alone, cystectomy preceded by a short course of preoperative radiotherapy (2000 cGy/5 fractions/1 week), or cystectomy followed by postoperative irradiation (5000 cGy/25 fractions/5 weeks or 3750 cGy/30 fractions/2 weeks). These patients were retrospectively analyzed.

RESULTS

The overall 5-year actuarial rate of distant metastasis was 23% (95% confidence interval, 21-25%), which was essentially the same in the 3 therapeutic groups. Both univariate and multivariate analyses revealed that the independent risk factors for distant metastasis were pelvic lymph node involvement (P = 0.005), pathologic stage (P = 0.004), and histopathologic grade (P = 0.05). Histologic type and local pelvic recurrence appeared in the univariate analysis as working risk factors; however, they were proven by multivariate analysis to be dependent on other risk factors. Patients who had none of the independent risk factors had a lower rate of distant metastasis (II%) and a high local control rate (88%). Those who had more than one risk factor had high distant metastasis rate (51%) and low local control rate (41%), regardless of the therapeutic modality used. The identified independent risk factors determined both the distant metastasis and the local control rates.

CONCLUSIONS

Unlike previous reports, this rigorous study of distant metastasis in bilharzial bladder cancer revealed an occurrence rate of 23%. This high rate was associated with pelvic lymph node involvement, pathologic stage, and histopathologic grade. Histologic type, local pelvic recurrence, or the addition of pre- or post-operative radiotherapy proved not to be independent risk factors.