Analysis of potential risk factors for cancer incidence in patients with aristolochic acid nephropathy from Wenzhou, China

Figures & data

Table 1. The type, management and status of cancer in the patients.

Cancer type (n)	Treatment regimen	Relapse (n)	Metastatic location (n)	Death (n)
Bladder cancer (16)	1. Simple cystectomy (1)	4
	2. Prophylactic bilateral radical cystectomy (2)			Cerebral hemorrhage (1)
	3. Conservative treatment (1)		Liver (1)	1
	4. Transurethral resection plus post-operative intravesical chemotherapy (12)		Psoas (1) Liver (2)	3
Bladder cancer + Upper urinary tract cancer (13)	Radical surgical removal	7	Abdominal (1)	1
				Cancer relapse (1)
					Cerebral infarction (1)
				Septic shock (1)
Upper urinary tract cancer (8)	Radical surgical removal	2	Liver (1)	1
			Psoas (1)	1
	Gastric and breast cancer (1)	Radical surgical removal
Breast cancer (1)	Radical surgical removal
Colorectal cancer (1)	Radical surgical removal	1	Liver (1)	1
Liver and bladder cancer (1)	Radiofrequency ablation of liver cancer followed by radical cystectomy
Cancer in right parotid and left renal pelvis and ureter (1)	Radical surgical removal	1	Psoas and abdominal (1)	1

Figure 1. Different renal replacement therapies seemed to be associated with cancer at specific locations of urinary system. Patient undergoing hemodialysis developed cancer mainly in bladder (72.72%), while patient receiving peritoneal dialysis had cancer predominantly in upper urinary tract (66.67%). Fisher’s exact test was performed to compare the proportion of cancers at different locations of urinary system in patients receiving hemodialysis versus peritoneal dialysis. p = 0.022. Renal transplant did not appear to be associated with cancer at any particular locations of urinary system.

Table 2. Analysis of potential risk factors for cancer incidence in the AAN patients.

	Patients with cancer (n)
	Before ESRD	After ESRD	Patients without cancer (n)	Total (n)	p Value
Age (mean ± SD)	58.46 ± 9.83	56.88 ± 12.57	56.48 ± 10.90		0.530
Gender					0.437
Male	12	17	24	53
Female	1	12	36	49
AA dosage* (Mu Tong consumption)					0.091
<60 g	0	3	17	20
60–200 g	5	4	18	27
>200 g**	8	22	25	55	0.048
Renal replacement therapy					0.590
Renal transplant	3	15	35	53
Hemodialysis	10	11	15	36
Peritoneal dialysis	0	3	10	13
Duration of therapy (y)	4.71 ± 4.41	4.62 ± 3.31	6.12 ± 3.48		0.139
Death	7	6	7	20	<0.05

The association of cancer incidence with age, gender, AA dosage, the type of renal replacement therapies, or the duration of renal replacement therapies was analyzed using multivariable logistic regression models. p < 0.1 was considered statistically significant.

*Indicates significant association of AA dosage with cancer incidence. Relative risk of cancer incidence in patients consuming moderate or high dose of AA compared with patients consuming low dose of AA was calculated.

**Indicates a significant increase in the relative risk of cancer incidence in patients consuming more than 200 g Mu Tong.

Table 3. Analysis of correlation between polymorphism and cancer incidence in the AAN patients.

Polymorphism type	Patients with cancer (n)	Patients without cancer (n)	Total (n)	Chi-square p value
NQO1 C609T				0.47
CC	8	7	15
CT	16	25	41
TT	3	7	10
CYP1A1 A4889G				0.858
AA	17	22	39
AG	8	14	22
GG	2	3	5