Preoperative marking of the proximal resection margin in esophageal cancer with a surgical fiducial marker: First experiences

Table 1 Baseline characteristics of study participants, n (%)/mean ± SD

Characteristic	Study population n = 10
Age, years	68 ± 6.9
Sex
Male	8 (80)
Female	2 (20)
ASA
ASA score: 2	3 (30)
ASA score: 3	7 (70)
cT11	0 (0)
cT2	3 (30)
cT3	5 (50)
cT4	2 (20)
cN01	5 (50)
cN1	3 (30)
cN2	2 (20)
Surgical procedure: Hybrid esophagectomy	8 (80)
Surgical procedure: Open esophagectomy	2 (20)

¹TNM classification of malignant tumors.

ASA: American society of anesthesiology.

Table 2 Histopathology and operation details, n (%)/mean ± SD

Characteristic	Study population n = 10
Tumor type: Adenocarcinoma	8 (80)
Tumor type: Mixed neuroendocrine non-neuroendocrine neoplasm	1 (10)
Tumor type: Mucoepidermoid carcinoma	1 (10)
pT11	4 (40)
pT2	1 (10)
pT3	5 (50)
pN01	5 (50)
pN1	3 (30)
pN2	2 (20)
Tumor regression scoring according to Mandard, 2	3 (30)
Tumor regression scoring according to Mandard, 3	4 (40)
Tumor regression scoring according to Mandard, 4	1 (10)
Tumor regression scoring according to Mandard, 5	1 (10)
No neoadjuvant treatment	1 (10)
Tumor size in millimeters	32.7 ± 23.8
Palpable tumor, yes	7 (70)
Palpable tumor, no	3 (30)
Microscopic distance to proximal tumor resection line, mm	37.3 ± 17.9
Macroscopic distance to proximal tumor resection line, mm	45.3 ± 17.3
R0 resection	10 (100)
R1 resection	0 (0)
Barrett’s dysplasia in resected tissue	2 (20)
No Barrett’s dysplasia in resected tissue	8 (80)

¹TNM classification of malignant tumors.

Table 3 Implantation details, n (%)/mean ± SD

Characteristic	Study population n = 10
Distance from incisors to proximal tumor border, cm	39.3 ± 5.8
Distance from surgeon’s proposed proximal resection line to BioXmark®, cm1	3.8 (± 1.1)
Number of implantations per patient	4
Amount of BioXmark® per implantation, μL	82 ± 17.5
BioXmark® visible on intraoperative ultrasound in vivo	6 (60)
BioXmark® not visible or missing data on intraoperative ultrasound in vivo	4 (40)
BioXmark® visible on intraoperative ultrasound ex vivo	3 (30)
BioXmark® not visible or missing data on intraoperative ultrasound ex vivo	7 (70)

¹A positive value means the line was proximal to BioXmark^®, and a negative value means the line was distal to BioXmark^®.