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Page 2 of 7 Mammana et al. Mini-invasive Surg 2020;4:37 I http://dx.doi.org/10.20517/2574-1225.2020.24
[2]
Blalock and colleagues , in 1939, were the first to report a dramatic improvement in symptoms following
thymectomy in a patient affected by a cystic thymic tumor and MG. Since then, several other reports
[3]
followed, highlighting a positive outcome of thymectomy in nonthymomatous MG . However, in the
absence of any formal evidence, the real benefit of this procedure remains in doubt.

[4]
Retrospective studies were analyzed by an in-depth review in 2000 ; while the majority of reports
demonstrated a favorable response from thymectomy in rates of disease remission or improvement, several
methodological flaws precluded the investigators from drawing firm conclusions. A major breakthrough in
the role of thymectomy for nonthymomatous MG was made only recently in 2016 by the Thymectomy Trial
[5]
in Non-Thymomatous Myasthenia Gravis Patients Receiving Prednisone Therapy (MGTX) . This large
international, randomized, single-blind trial was conducted to determine whether extended transsternal
thymectomy combined with a standardized prednisone protocol would be superior to prednisone alone
after 3 years. A total of 126 patients from 36 institutions affected by generalized nonthymomatous MG,
with strict inclusion criteria (age of 18 to 65 years, Myasthenia Gravis Foundation of America (MGFA)
clinical class II to IV disease, positivity for acetylcholine-receptor (AChR) antibody, and disease duration
less than 5 years) were randomized into the two treatment arms. The results from this study unequivocally
demonstrated that thymectomy was beneficial with respect to clinical outcomes and requirements for
[6]
prednisone therapy in patients affected by generalized nonthymomatous MG .

Over the years, surgical approaches to thymectomy have evolved, with the aim of reducing surgical
morbidity and of increasing the acceptance of such procedure for benign diseases, especially in young
patients. Minimally invasive approaches include transcervical, videothoracoscopic (VATS), subxyphoid,
[7]
and robot-assisted (RATS; robot-assisted thoracic surgery) thymectomy . Various authors and meta-
analyses have demonstrated that minimally invasive approaches to thymectomy are associated with
better surgical outcomes and fewer surgical complications than the transsternal open approach, with no
[8]
significant differences in MG complete remission rates .
Currently, there is no definitive evidence in the literature that supports the use of one minimally invasive
approach over the others; therefore, the decision is mostly based on the surgeon’s preference. Factors that
play a role in the choice of the surgical approach are perceived difficulty, ergonomics and the learning curve
of the procedure, as well as the possibility of carrying out a thorough, extended thymectomy, which means
[9]
the removal of the whole thymus with the surrounding fatty tissue of the neck and the mediastinum . This
is a capital concept in surgery for MG, as various authors have demonstrated that ectopic thymic foci are
interspersed in the anterior mediastinal fat in up to 98% of patients, and that the removal of all thymic foci
increases the probability of a complete remission of MG after surgery [10,11] .

At the Division of Thoracic Surgery of Padua University Hospital (Italy), starting from 2002, we developed
a program of RATS thymectomy, and we currently adopt this approach for all patients who undergo
[12]
thymectomy for nonthymomatous MG . In this article, the rationale, indications, technique and outcomes
of robotic thymectomy for MG are reviewed.

RATIONALE FOR ROBOTIC THYMECTOMY
The most widespread robotic system nowadays is the Da Vinci surgical system (Intuitive Surgical, Inc.
Sunnyvale, CA, USA). This consists of a designed surgeon’s console, a vision system, and a patient-side
cart supporting the interactive robotic arms. The console is connected to the video system and the robotic
cart, and it represents the interface between the surgeon and the robotic system. The surgeon sees the
operative field through binoculars located in the upper part of the console and his/her fingers grasp the
master controls below the display and moves the robotic arms. The system translates the three-dimensional