Prevention of Recurrent Superficial Bladder Tumors by Oral Etretinate: Preliminary Results of a Randomized, Double Blind Multicenter Trial in Switzerland

Abstract

Retinoids influence the proliferation and differentiation of epithelial tissues. Preliminary results of a double-blind randomized trial in the prevention of recurrent superficial bladder tumors are promising. Patients treated with an oral etretinate tend to have less tumor recurrences and transurethral resections. The number of multifocal recurrences after 12 months of treatment is significantly lower (p less than 0.02). There also are less dropouts owing to inefficacy of treatment (p less than 0.036).

Vitamin A supplements, fried foods, fat and urothelial cancer. A case‐referent study in Stockholm in 1985–87

“…The retinoids used in vitamin A supplements are chemically more closely related to retinol than to the plantderived active carotene, and the evidence of a protective effect against cancer is stronger for active carotene than for retinol (Ziegler, 1989). The retinoids used in treating superficial cancer of the urinary bladder (Alfthan et al, 1983;Studer et al, 1984) probably have a stronger biological effect than the retinyl-esters used in vitamin supplements.…”

“…Retinoids, analogues of vitamin A, are used to treat superficial cancer of the urinary bladder (Alfthan et al, 1983;Studer et al, 1984). Animal data support an inhibitory effect of retinoids on carcinogenesis in the urinary bladder In the industrialized world some 130,000 cases of urinary bladder cancer occurred in 1980 as estimated by Parkin et al (1988).…”

The effectiveness of retinoic acid treatment in bladder cancer: Impact on recurrence, survival and TGFα and VEGF as end-point biomarkers.

“…There were fewer dropouts owing to inefficacy of treatment. 22 A third study showed a recurrence rate over two years of 38% in the control group patients with superficial bladder tumors, whereas, recurrence rate was 18% significantly lower in the etretinate-treated group with a higher cumulative recurrence inhibition rate. Side-effects (dry lips, cheilitis, stomatitis, dermal desquamation, etc.)…”

“…20 However, several historically controlled as well as prospectively randomized, placebo-controlled trials of retinoids in superficial bladder cancer were disappointing or inconclusive and reported significant patient toxicities even with the least toxic natural and synthetic retinoids. [21][22][23][24][25][26][27] We aimed at investigating the potential retinoid redifferentiation therapy for bladder cancer, in our local Upper Egyptian patients with their distinct ethnic and ecological predisposing characteristics, as the major cancer reported. We suggested that underestimation of resistance development through hastened clearance by the retinoid-inducible cytochrome P450s (Cyp450s) was a major cause for failure of previous studies.…”

Adjuvant Treatment with a Vitamin A Analogue (Etretinate) after Transurethral Resection of Superficial Bladder Tumors

“…A coding and transcription error of approximately 10% was found. This, together with the longer follow-up explains some minor differences between the preliminary findings that were reported 10 years ago and these final results [11], Student's t test, the x2 test, the Wilcoxon test and the Mann-Whitney U test or Fisher test were used for statistical evaluation [11][12][13][14],…”