Fig. 4

Histopathological observation and CTC count in pre/post-chemotherapy in CTC positive HNSCC (A) Histopathological representation of studied subjects based on Grade. Two images in the first column depict the image of two patients (Patients 1 and 2) of Grade I, the middle column represents the images of two patients (Patients 3 and 4) of Grade II, and the last column represents the images of two patients (Patients 5 and 6) of Grade-III. Histopathological slides were examined using the Hematoxylin and Eosin (H/E) procedure. B Distribution of CTC-positive patients based on the grades and CTCs count (n = 64). Black circular dots represent the number of CTCs (n = 64). Data is represented here as mean ± SD and one-way ANOVA was carried out to compare the number of CTCs and the Grade of CTC-positive patients and found highly significant. C The number of CTCs in blood samples was tested before and after three cycles of chemotherapy (n = 10). Mann–Whitney unpaired nonparametric unpaired t-test was performed and found highly significant. **p-value < 0.01, ***p-value < 0.005