Detection of circulating tumor cells in peripheral blood of patients with tongue squamous cell carcinoma and its relationship with clinical features and prognosis: a retrospective study

Circulating tumor cells (CTCs) are a promising biomarker for assessment of prognosis. The study was to analyse the relationship between preoperative and postoperative peripheral blood CTC and clinical features and prognosis in patients with tongue squamous cell carcinoma (TSCC).

85 with TSCC and 30 tongues with benign disease who underwent surgical treatment from May 2016 to May 2023 were retrospectively analysed. CTC testing was performed twice for TSCC group before and after surgery and only before the surgery for the benign disease group, only one test was performed before surgery.The association of CTCs with clinical features and progression-free survival (PFS) was also analyzed.

The positive rates of CTCs in patients with TSCC were 90.6% before treatment and 72.9% after treatment, respectively. CTCs were not detected in patients with benign disease group before treatment. There was no significant difference in the number of CTCs before and after treatment in patients with disease progression (P > 0.05). However, the number of CTCs after treatment in patients with disease remission (DR) and stable disease (SD) was significantly lower than before treatment, and the difference was statistically significant (P < 0.05). The results of the log-rank test demonstrated that the postoperative CTC was associated with the PFS (P < 0.05), whereas the preoperative CTC was not related to the PFS. The Cox proportional hazard regression model indicated that postoperative CTC and lymph node metastasis were independent risk factors.

Postoperative CTCs may be an independent risk factor for a poor prognosis in patients with TSCC and CTC may serve as a valuable biomarker for prognostic monitoring for TSCC patients.