The value of detection of circulating tumor cells in predicting lymph node metastasis of urothelial carcinoma

Abstract

Objective To discuss the application experience and predictive value of circulating tumor cells for urothelial carcinoma. Methods The clinical data of 96 patients with urothelial carcinoma treated by Beijing Cancer Hospital Urologic Department between September 2017 and September 2019 were analyzed retrospectively to evaluate relationship between the number of CTCs and pathological outcome. The mean age of the entire cohort was 62(40-87)years, with 74 males and 22 females. There were 13 cases of upper urinary tract tumors (pyelocarcinoma and ureteral carcinoma), 83 cases of bladder carcinoma, and 12 cases of lymph node metastasis. There were 77 cases of primary onset and 19 cases of recurrence. 68 cases in single focus group and 28 cases in multiple group. There were 29 cases in non infiltrative Ta stage, 42 cases in infiltrative lamina propria T1 stage, 16 cases in infiltrative muscle T2 stage, and 9 cases in extra-muscular≥T3 stage. At least 3ml of peripheral blood was collected after fasting for at least 8 hours, After cleavage and centrifugation, immunomagnetic beads were added, folate probe was added, and then amplification was carried out. Then the copy number of CTCs in each ml of blood was calculated. Logistic linear regression was used to analyze the risk factors of lymph node metastasis. Results The mean CNC of all patients was 12.3±7.3; the mean CNC of ≤62 years old group was 10.8±4.2; the mean CNC of >62 years old group was 13.7±9.2; the mean CNC of initial cases was 11.5±5.3; the mean CNC of recurrent cases was 15.5±12.2. Age (P=0.135) and frequency of onset (P=0.087) had no effect on the number of CTCs. The average CNC of single focus group was 10.5±5.2, multiple focus group was 16.5±9.7, Ta stage group was 8.2±2.3, T1 stage group was 12.0±4.4, T2 stage group was 16.4±6.8, and ≥T3 stage group was 19.5±16.6. The number of lesions (P<0.001) was significantly correlated with pathological T stage (P<0.001) and the number of CTCs. Univariate regression analysis showed that T stage (P<0.001) and the number of CTCs (P=0.02) might be correlated with lymph node metastasis; multivariate analysis showed that only T stage could be used as an independent predictor of lymph node metastasis (P=0.002). Conclusions CTCs can be used to predict lymph node metastasis of urothelial carcinoma. Key words: Carcinoma, transitional cell; Urothelial carcinoma; Bladder cancer; Circulating tumor cells (CTCs); Lymph node metastasis; Risk factor