Bladder cancer recurrence in papillary urothelial neoplasm of low malignant potential (PUNLMP) compared to G1 WHO 1999: a population-based study

Figures & data

Figure 1. Flow chart describing the selection, exclusion, and follow-up of patients in the study. NMIBC: non-muscle invasive bladder cancer; SNRUBC: Swedish National Registry of Urinary Bladder Cancer.

Table 1. Baseline characteristics for patients in the Swedish National Registry of Urinary Bladder Cancer (SNRUBC) diagnosed in 2004–2008 with papillary urothelial neoplasm of low malignant potential (PUNLMP) or TaG1 bladder cancer.

	PUNLMP (n = 135)		TaG1 (n = 2176)
	n	%	n	%
Year of diagnosis
2004	24	(18)	357	(16)
2005	38	(28)	450	(21)
2006	25	(19)	428	(20)
2007	20	(15)	455	(21)
2008	28	(21)	486	(22)
Age
Mean	66		69
SD	13		12
Age (dichotomized)
≤65	60	(44)	815	(37)
>66	75	(56)	1361	(63)
Sex
Male	96	(71)	1577	(72)
Female	39	(29)	599	(28)
CCI
0	91	(67)	1323	(61)
1	16	(12)	354	(16)
2	15	(11)	294	(14)
≥3	13	(10)	205	(9.4)
Married
No	51	(38)	869	(40)
Yes	84	(62)	1307	(60)
Education
Low	56	(43)	933	(44)
Intermediate	52	(40)	806	(38)
High	22	(17)	399	(19)
Health care region
Stockholm/Gotland	38	(28)	413	(19)
Uppsala/Örebro	18	(13)	459	(21)
South-eastern	9	(7)	253	(12)
Southern	11	(8)	439	(20)
Western	17	(13)	440	(20)
Northern	42	(31)	172	(8)

Age is stratified above or below the mean age in the study population (≤65 and >66 years). Charlson Comorbidity Index (CCI) is calculated for a 10-year period before diagnosis. Educational level is categorized as low (≤9 year education), intermediate (10–12 years), and high (≥13 years), corresponding to mandatory school, high school, and college/university.

Figure 2. Kaplan–Meier graphs with a cumulative incidence of recurrence for PUNLMP and TaG1.

Table 2. Risk of recurrence evaluated in a Cox regression model.

	Recurrence
	N	HR (multivariate)	95% CI	p-Value
Grade WHO 1999
PUNLMP	135	1	–	–
TaG1	2176	1.6	1.2–2.0	<0.001
Age
(Continuous)	2311	1.0	1.0–1.0	<0.001
Sex
Male	1673	1	–	–
Female	638	1.1	0.93–1.2	0.45
CCI
0	1414	1	–	–
1	370	1.2	1.1–1.4	0.01
2	309	1.5	1.3–1.7	<0.001
≥3	218	1.6	1.4–1.9	<0.001
		p (overall): <0.001
Married
No	920	1	–	–
Yes	1391	0.96	0.86–1.1	0.46
Education
Low	989	1	–	–
Intermediate	858	1.1	0.96–1.2	0.18
High	421	0.92	0.79–1.1	0.29
Missing	43	p (overall): 0.08
Health care region
Stockholm/Gotland	451	1	–	–
Uppsala/Örebro	477	1.3	1.1–1.5	0.01
South-Eastern	262	0.98	0.80–1.2	0.86
Southern	450	1.3	1.1–1.5	0.004
Western	457	1.4	1.2–1.6	<0.001
Northern	214	1.1	0.85–1.3	0.66
		p (overall): <0.001

HR: hazard ratio; PUNLMP: papillary urothelial neoplasm of low malignant potential; CCI: Charlson Comorbidity Index. Education was stratified as follows: Low (≤9 years of education), intermediate (10–12 years), and high (≥13 years).

Table 3. Recurrence and progression in previous studies with $\ge$50 cases of PUNLMP (adapted from Hofmann et al.) [7].

Study	Number of cases	Recurrence (%)	Progression (%)	Mean follow-up
Present study	135	21	0.7	3.6 years
Hentschel et al. [5]	127	51	3.9	38.4 months
Oosterhuis et al. [10]	116	26	2.6	79 months
Cheng et al. [11]	112	27	3.6	12.8 years
Holmäng et al. [12,13]	95	35	0	>5 years
Fuji et al. [14]	50	60	8.0	11.7 years

Haggstrom C, Liedberg F, Hagberg O, et al. Cohort profile: the Swedish National Register of Urinary Bladder Cancer (SNRUBC) and the bladder cancer data base Sweden (BladderBaSe). BMJ Open. 2017;7(9):e016606.

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Holmang S, Hedelin H, Anderstrom C, et al. Recurrence and progression in low-grade papillary urothelial tumors. J Urol. 1999;162(3 Part 1):702–707.

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Fujii Y, Kawakami S, Koga F, et al. Long-term outcome of bladder papillary urothelial neoplasms of low malignant potential. BJU Int. 2003;92(6):559–562.

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