Observation of tumour thickness and resection margin at surgical excision of primary oral squamous cell carcinoma—assessment by ultrasound

(a) Partially resected tongue tumour (B) with metal instrument (C) in the cut to provide a surface to reflect ultrasound. Ultrasound probe (A) is placed on the surface of tongue (labels match diagram in Fig. 3). Patient 9 in Table 1. (b) Ultrasound image of part (a). Note 2 pairs of electronic cursors to measure the distance from tongue surface to the deep margin of the tumour, and from the latter to the surgical cut. Field width: 26mm. (c) Line diagram of part (b). S: tongue surface. T: tumour. M: metal instrument (bright white line). D: deep surgical margin. The surgical margin is clearly shown to be separate from the hypoechoic tumour. The gap between D and M is filled with water during ultrasound imaging. Note 2 pairs of cursors to show where measurements were made.

(a) Partially resected tongue tumour with ultrasound-reflective instrument in the cut. Patient 1 in Table 1. (b) Ultrasound image of part (a). In this case, the surgical cut is quite close to the deep margin of the tumour, rendering the latter difficult to delineate (see Fig. 4 for macroscopic specimen). Field width=26mm. (c) Line diagram of part (b). T: tumour. M: metal instrument. Note 2 pairs of cursors to show where measurements were made.

Diagram of partially resected tumour (B) being assessed by ultrasound for depth clearance, with a reflective instrument (C) in the surgical cut. A: ultrasound probe (contra-angle).

(a–c) Macroscopic specimen (a) and diagram (b) of excised tongue squamous cell carcinoma (same case as in Fig. 2). In part (b), note proximity of deep tumour margin T to the surgical margin Q. S: surface of tongue and of tumour. Part (c) is the ultrasound image of the tumour before excision. Note how well the tumour outline matches that in the macroscopic specimen.

Scatter plot of tumour thickness measurements by ultrasound and by histology. Note the plotted points nearly all lie on a straight line, showing a strong positive relationship (P<0.01).