Indocyanine Green Fluorescence Imaging in the Surgical Management of Skin Squamous Cell Carcinoma

Figures & data

Table 1 Demographic and Clinical Characteristics of the Patients with SSCC

	The Experimental Group Received ICG Fluorescence Imaging (n=60)	The Conventional Group Without ICG Fluorescence Imaging (n=38)
Age (y)	51.3 ± 16.6	48.9 ± 12.4
Scarring time (y)	29.9 ± 16.8	33.4 ± 17.9
Duration of ulcer (y)	15.2 ± 15.9	11.2 ± 16.2
Gender (n)
Male	44	21
Female	16	17
Anatomical location (n)
Head and neck	21	12
Upper limb	7	4
Lower limb	32	22
Ulcer area (cm^2)	87.1 ± 57.2	71.4 ± 35.5
<50 (n)	34	18
50~100 (n)	14	12
>100 (n)	12	8
Degree of differentiation (n)
Moderately differentiated (MD)	2	1
Well differentiated (WD)	58	37
Lymph node metastases (n)
With	2 (MD)	2 (WD)
	3 (WD)
Without	55	36

Figure 1 Three types of ICG fluorescence imaging.

Figure 2 Preoperative ICG fluorescence imaging of a scar cancer of left medial malleolus. (A) The gross appearance; (B) Visible light image under near-infrared imaging; (C) Fluorescence image under preoperative imaging. Red arrows indicate tissues with strong fluorescence signals; (D) The HE staining of the biopsied tumor tissues. The scale bar indicates 100 μm.

Table 2 Intraoperative Real-Time ICG Fluorescence Imaging (IFI) and Recurrence

	Total Number of Cases (n)	Number of Recurrent Cases (n)	Recurrence Rates (%)
Receiving radical resection under IFI	53	5	9.4
With residual fluorescent signals	24	3	12.5
Without any residual fluorescent signals	29	2	6.8
Receiving routine radical resection without IFI	35	4	11.4

Figure 3 A male with scar carcinoma of left inguinal region and thigh, receiving radical resection under intraoperative real-time ICG fluorescence imaging. (A) The gross appearance of the tumor; (B) The gross appearance of the wound after tumor resection; (C) Visible light image of the wound under intraoperative imaging; (D) Fluorescence image of the wound under intraoperative imaging. Red arrow indicates residual fluorescent signals; (E) The HE staining of the biopsied tissues in the superior margin of the wound after tumor resection; (F) The HE staining of the biopsied tissues in the outer margin of the wound after tumor resection; (G) The HE staining of the biopsied tissues in the medial lower margin of the wound after tumor resection. The scale bars indicate 200 μm.

Figure 4 A female with squamous cell carcinoma of scalp, receiving preoperative and intraoperative ICG fluorescence imaging. (A) The gross appearance of the tumor; (B) Visible light image of the tumor under preoperative imaging; (C) Fluorescence image of the tumor under preoperative imaging; (D) Drawing the surgical margin based on the range of fluorescence; (E) The gross appearance of the wound after tumor resection; (F) Visible light image of the wound under intraoperative imaging; (G) Fluorescence image of the wound under intraoperative imaging; No residual fluorescence signal was found; (H) The HE staining of the resected tumor tissues. The scale bar indicates 200 μm.

Table 3 Lymph Nodes Examination

	Total Number of Cases (n)	Inguinal	Popliteal	Axillary
Lymphadenopathy	15	12	2	1
Lymph node metastases	5	4	1	0
Chronic inflammation	4	2	1	1
Without pathological biopsy	6	6	0	0

Figure 5 Preoperative ICG fluorescence imaging of the sentinel lymph nodes on the right lower limb. (A) The surface location of the groin lymph nodes; A-1. Visible light image of the groin lymph nodes; A-2. Fluorescence image of the groin lymph nodes; (B) The surface location of the lymph nodes on the inner right thigh. B-1. Visible light image of the lymph nodes on the inner right thigh; B-2. Fluorescence image of the lymph nodes on the inner right thigh; (C) The HE staining of the resected tumor tissues. The scale bar indicates 100 μm.

Figure 6 Intraoperative ICG fluorescence imaging of the well differentiated squamous cell carcinoma of the right leg. (A) The gross appearance of the tumor; (B) The gross appearance of the operation area in the right groin; (C) The postoperative residual limb; (D) The gross appearance of two lymph nodes in the right groin; (E) Visible light image of the two groin lymph nodes; (F) Fluorescence image of the two groin lymph nodes; (G) The gross appearance of another two lymph nodes in the right groin; (H) Visible light image of another two groin lymph nodes; (I) Fluorescence image of another two groin lymph nodes; (J) The HE staining of the resected tumor tissues. The scale bar indicates 100 μm.