Changes of serum p53 antibodies and clinical significance of radiotherapy for esophageal squamous cell carcinoma

Table 1 Sequential change of positive rate of serum p53-Abs in EC patients before and after radiotherapy

Groups	n	-	+	%	χ2	P
Before RT	46	28	18	39.1	0.000	1.0001
20 Gy	46	28	18	39.1	0.187	0.6662
40 Gy	46	30	16	34.8	4.696	0.0303
60 Gy	46	39	7	15.2	6.646	0.0104

¹Before RT vs 20 Gy;

²Before RT vs 40 Gy;

³40 Gy vs 60 Gy;

⁴Before RT vs 60 Gy.