Author
N° patients
SA
Masaoka stage I/II
TS (cm)
5-year survival (%)
FU (months)
RR (%)
OC (%)
OT (min)
POS (days)
Roviaro et al. [3]
22
uVATS
22
–
–
–
4.5
4.5
75a
6a
Cheng et al. [12]
44
uVATS
27/17
7.7a
100
34.6a
0
0
194a
7.6a
Odaka et al. [14]
22
uVATS
–
–
–
21.6a
0
0
194a
4.6a
Agasthian et al. [15]
50
uVATS
25/25
5a
100
58a
2
0
150a
5a
Pennathur et al. [11]
18
bVATS
5/13
3.5a
100
27b
0
0
–
2.9
Takeo et al. [16]
34
bVATS
15/19
5.2a
100
65a
2.8
0
219a
10.5a
Kimura et al. [17]
45
uVATS
41/4
4.8a
–
–
6.7
0
180a
14a
Liu et al. [13]
76
u/bVATS
57/19
4.6a
100
61.9a
2.6
1.3
142a
7.1a
Odaka et al. [18]
57
uVATS
29/28
4.3a
100
43a
1.7
0
225a
4a
Mussi et al. [19]
13
Robotic
7/6
3.3a
100
14.5b
0
7.7
139a
4a
Marulli et al. [20]
79
Robotic
30/49
3.7a
90
51.7a
1.3
1.3
165a
4.4a
Ye et al. [10]
23
Robotic
21/2
2.9a
–
16.9a
0
0
97a
3.7a
Schneiter et al. [21]
19
Robotic
8/11
4.0b
–
26b
11.1
0
–
5b
Is There a Technological Advantage of Robotic Compared to VATS Thymectomy?
Many surgeons are still reluctant to undertake a VATS or robotic thymectomy in patients with thymoma for several reasons that stem from technical and oncologic concerns. The main technical reasons against VATS are the following: the upper mediastinum is a delicate and, for VATS, difficult-to-reach anatomical area, with vulnerable large vessels and nerves. The two-dimensional view of the operative field, the surgeon’s tremor enhanced by the thoracoscopic instruments and the fact that the instruments do not articulate, make it difficult to operate in a fixed and tiny three-dimensional space such as the mediastinum. Moreover, the VATS thymectomy is considered a technically challenging operation requiring a long learning curve [6]. The oncologic concerns are related to the possible breach of tumor capsule with risk of tumor seeding locally or in the pleural cavity and to the difficult evaluation of resection margins with reduced oncologic accuracy and safety.
The introduction of robotic surgical systems has added a new dimension to conventional VATS providing additional advantages and overcoming some technical and methodological limits: (1) the improved dexterity of instruments that can articulate with 7° of freedom and rotate 360°, allows complex three-dimensional movements superior to that permitted by conventional minimally invasive instruments, enhancing the dissection safe around vessels and nerves and more comfortable in tiny and remote areas such as the superior horns or the contralateral mediastinum; (2) the high-resolution, three-dimensional real-time video image permits the best possible and magnified view of the surgical field, and (3) the filtering of hand tremors allows greater technical precision. To date, however, no studies demonstrated a superiority of robotic approach for thymoma resection compared with standard VATS (level of evidence very low). As reported in Table 54.1, the rate of open conversion, the operative time, the size of the tumor were comparable in VATS and robotic studies. No papers focused on the percentage of capsule breaching, on the rate of open conversion related to technical reasons and on the rate of complete resection (level of evidence very low). In addition there is a significant difference between series regarding the rate of Masaoka stage I and II, the extension of resection, the size of the tumor, the selection criteria for minimally invasive approach and the surgical technique: some authors [20] adopted a “no-touch technique” with an “en bloc” resection of thymus and perithymic fat tissue according to the International Thymic Malignancy Interest Group criteria [22], while other authors [14, 23] preferred a partial thymectomy. In some studies [11, 19] a limit of 3 cm of diameter of the tumor was established, in other series [13, 15, 18, 20] a limit of 5 cm was considered safe, while some authors [12, 16] accepted also greater size. These differences were independent of surgical approach (VATS or robotic).