Trans-anal minimally invasive surgery for rectal neoplasia: Experience from single tertiary institution in China

Table 1 Patients’ clinical and pathological characteristics

	Benign (n = 3)	Malignant1 (n = 22)	All (n = 25)
Mean age, yr (SD)	55.3 (7.5)	51.3 (13.8)	51.8 (13.2)
Gender
Male	1	8	10 (40%)
Female	2	14	15 (60%)
Mean body mass index, kg/m2 (SD)	23.9 (1.3)	23.9 (3.0)	23.9 (2.9)
Pre-TAMIS excision	0	5	5 (20%)
Mean lesion size, cm (SD)	1.1 (0.7)	1.1 (0.5)	1.1 (0.5)
Mean distance from anal verge, cm (SD)	9.3 (0.6)	8.3 (1.6)	8.4 (1.6)
Final pathology
Benign	3		3 (12%)
Malignant			22 (88%)
Adenocarcinoma		6	6 (24%)
Mid-high differentiation		6	6 (24%)
Low differentiation		0	0
T0 (no residual tumor)		0	0
T1		5	5 (20%)
T2-3		1	1 (4%)
NET		16	16 (64%)
Lymph-vascular invasion	0	1	1 (4%)
Positive margin	0	5	5 (20%)
Position
Lloyd-Davies	3	15	18 (72%)
Jackknife	0	7	7 (28%)
Mean duration of surgery, min (SD)	58.0 (37.0)	61.8 (24.7)	61.3 (25.5)
Mean blood loss, mL (SD)	5 (0)	8.6 (4.4)	8.2 (4.3)
Mean length of post-operative stay	2.3 (1.5)	2.8 (1.4)	2.7 (1.4)

¹Includes in situ and invasive adenocarcinoma and neuroendocrine tumors. NET: Neuroendocrine tumors.

Table 2 Characteristics of patients with positive resection margin

Patients’ No	Age	Gender	BMI (kg/m2)	Distance from anal verge (cm)	Diameter (cm)	Surgery duration (min)	Position	Post-op stay	Type of positive margin	Pathology	Post-op treatment
1	58	2	19.9	7	2	50	Lloyd-Davies	1	Lateral	Adenocarcinoma	Curative surgery
2	75	2	23.2	10	2	60	Lloyd-Davies	1	Basal	NET-G1	Imatinib
3	64	2	26.1	6	1.5	45	Lloyd-Davies	4	Basal	NET-G1	Imatinib
4	63	2	20.0	10	0.5	60	Lloyd-Davies	2	Lateral	NET-G1	Imatinib
5	59	1	24.8	8	1.5	30	Lloyd-Davies	3	Lateral	Adenocarcinoma	Chemo-radiation

NET: Neuroendocrine tumors.