Bladder perforation during transurethral resection of bladder tumour is not a result of a deficient structure of the bladder wall

Table 1 Basic oncological and surgical characteristics of the study population (per protocol analysis)

		Group 1 (perforation)	Group 2 (no perforation)	P value (group 1 vs. group 2)	Total
Number of patients		11	13	n.a.	24
Men		7	6		11
Women		4	7	0.39 *	13
Mean age of patients (years)		74.8	72.3	0.32 **	73.5
% of recurrent tumours		45.5	38.5	0.73 *	41.7
Mean recurrence rate (for recurrent tumours)		0.58/year	1.18/year	0.17 ***	0.92/year
Mean tumour diameter (centimetres)		2.25	1.68	0.45 ***	1.94
% of operations performed by residents in training		45.5	53.8	0.22 *	50.0
Stage of bladder cancer	Ta	8	13	0.13 *	21
	Tis	0	0		0
	T1	2	0		2
	≥ T2	1	0		1
Cancer grade	Low grade	6	11	0.11 *	17
Cancer grade	High grade	5	2	0.11 *	7

Stage of bladder cancer (according to TNM classification)
Ta non-invasive papillary carcinoma, Tis carcinoma in situ, T1 tumour invades subepithelial connective tissue, T2 tumour invades the muscle
*Pearson’s chi-square test
**unpaired t test
***Mann-Whitney U test

ISSN: 1477-7819