The Frequency of Circulating Tumour Cells and the Correlation with the Clinical Response to Standard Chemoradiotherapy in Locally Advanced Nasopharyngeal Carcinoma: A Prospective Study

Figures & data

Figure 1 Typical CTCs and white blood cells. (A) imFISH identified DAPI-positive, CD45-negative CTCs with more than two CEP8 signals and DAPI-positive, CD45-positive white blood cells with two CEP8 signals. (B) CTCs according to the number of CEP8 signals: 3, triploid; 4, tetraploid; and 5 or more, multiploid. Arrows indicate CTCcells.

Table 1 Demographic and Clinical Characteristics of Patients with and Without Circulating Tumor Cells

	No. of Patients (%)			P
Total N=50	CTC-Negative (N=23)	CTC-Positive (N=27)
Sex
Male	30 (60)	13 (57)	17 (63)	0.64
Female	20(40)	10(43)	10(37)
Age
<40	6(12)	2 (9)	4 (15)	0.60
40–60	36 (72)	16 (70)	20 (74)
>60	8 (16)	5 (22)	3 (11)
Biopsy history
Positive	10 (20)	5 (22)	5 (19)	1.0
Family history
With positive family history	16(32)	9(39)	7(26)	0.32
Smoking status
Positive^a	25 (50)	12 (52)	13 (48)	0.77
Stage
III	28 (56)	12 (52)	16 (59)	0.86
IVa	15 (30)	8 (35)	7 (26)
IVb	7(14)	3(13)	4(15)
T stage
T2	6 (12)	2 (9)	4 (15)	0.66
T3	28 (56)	12 (52)	16 (59)
T4	16 (32)	9 (39)	7 (26)
N stage
N0–N1	11 (22)	6 (26)	5 (19)	0.66
N2	32 (64)	14 (61)	18 (67)
N3	7 (14)	3 (13)	4 (15)

Note: ^aIncludes both former and current smokers.

Table 2 CTC Changes Among Patients with and Without Complete Response to Treatment

	No. of CTC (Mean ± SD)		P
	Before Treatment	After Treatment
Patients with CR
Triploidy	2.61±2.25	0.91±2.37	0.017
Tetraploidy	0.48±0.67^a	0.09±0.29	0.015
Multiploidy	0.61±0.89	0	0.003
Patients without CR
Triploidy	5.67±7.45	0.5±0.84	0.151
Tetraploidy	2.00±2.27^a	0	0.136
Multiploidy	1.67±1.97	0.17±0.41	0.122

Notes: ^aNumbers of tetraploidy CTC before treatment was significantly different among patients with CR and patients without CR (P=0.019).

Abbreviations: CR, complete response; CTC, circulating tumor cell; NS, not significant; SD, standard deviation.

Figure 2 The change in total CTC count before and after treatment in baseline CTC-positive LANPC patients. **P<0.001.

Table 3 Univariate and Multivariate Regression Analyses of Predictors for Complete Response to the Treatment in Patients with Locally Advanced Nasopharynx Carcinoma

Variable	Univariate^a		Multivariate^b
OR (95% CI)	P-Value	OR (95% CI)	P-Value
Age	1.1 (1.1–1.2)	0.008	1.1 (1.1–1.3)	0.005
Gender	2.6 (0.8–8.3)	0.11
Positive total CTC	0.5 (0.1–1.4)	0.17
Triploidy CTC	0.9 (0.7–1.1)	0.31
Tetraploidy CTC	0.5(0.2–1.1)	0.045
Multiploidy CTC	0.5(0.2–1.2)	0.09

Notes: ^aUnivariate logistic regression analysis was used to investigate variables as potential predictors of complete response to the treatment. Variables included, age, gender, TNM stage, positivity of circulating tumor cells; ^bmultivariate analysis was performed using the backward method.

Abbreviations: CI, confidence interval; CTC, circulating tumor cells.

Table 4 The Correlation Between the Number of Positive CTC Before Treatment and Clinical Response After Treatment and During Follow-Up

Clinical Response	No. of Patients		P
CTC-Negative	CTC-Positive
After treatment
CR	13	10	0.17
Non-CR	10	17
First follow-up^a
CR	13	17	0.64
Non-CR	10	10
Second follow-up^b
CR	17	18	0.58
Non-CR	6	9

Notes: ^aThree months after the treatment; ^bthree years after the treatment.

Abbreviations: CR, complete response; CTC, circulating tumor cell.

Table 5 Progression-Free and Overall Survival in LANPC Patients with Circulating Tumor Cells

	No. of Patients	No. of Relapses (%)	PFS Rate at 2 Years (95% CI)	p Value by log rank test
CTC-positive	27	7 (26%)	75% (0.6–0.9)	0.03
CTC-negative	23	1 (4%)	92% (0.8–1.0)
	No. of patients	No. of deaths (%)	OS rate at 2 years (95% CI)
CTC-positive	27	3 (11%)	91% (0.8–1.0)	0.09
CTC-negative	23	0 (0)	100%

Abbreviations: CI, confidence interval; CTC, circulating tumor cells; No, number; PFS, progression-free survival; OS, overall survival.