The logic of the robotic revolution in gynecologic oncology

Abstract

The DaVinci Robotic Surgical System (Intuitive, Sunnyvale, California, USA) is changing the surgical landscape for gynecologic cancer in the US and in many other places in the world. Yet, there is still much criticism in the media, by other medical professionals, and by medical economists about the appropriateness of such a growing focus on robotic approaches [1]. Minimally invasive approaches for the surgical treatment of endometrial cancer, and to a lesser extent cervical cancer, have been described since the early 1990s, with more recent high-quality randomized trials such as the Gynecologic Oncology Group LAP 2 showing equivalency of cancer outcome and survival to classical open surgery, with reduced adverse events [2–4]. In addition, patient acceptability is high, with an overall net benefit economically, due to shorter hospital stays, faster recovery times, and return to work. Despite these obvious advantages, and improved technology over the past two decades, laparoscopic treatment of endometrial and cervical cancer has been slowly adopted, for a number of reasons including limited dexterity with traditional laparoscopic instruments, poor ergonomics, unsteady two-dimensional field, and a steep learning curve. With limited numbers of highly skilled laparoscopic surgeons to do thorough staging procedures and/or radical surgery, incorporation of laparoscopic surgery as a standard approach for these cancers has been inconsistent at best. Robotic minimally invasive approaches to gynecologic cancers are, however, quickly changing that scenario, and bringing the advantages of the minimally invasive approach to much higher numbers of patients. Surgeons familiar with the platform easily recognize the distinct operating advantages including three-dimensional high-definition field, stable camera view, tremor reduction, wristed hand motion, and more instruments under direct surgeon control. For a gynecologic oncologist working in the US today, the sense of dramatic evolution in the surgical armamentarium is almost palpable, and it certainly seems that patients are benefitting. So what then is the criticism, and is it logical? The essence of the main criticism is that the system is too costly, that each individual procedure performed with the system is more costly, and that patient outcomes are not improved over traditional laparoscopic approaches. Since there is emotion on both sides of the debate, it can be useful to break it down logically. If we analyze the ‘robotic’ criticism as a syllogism, it could be the following: ’If P then Q.’ If a surgery is more costly (robotics), then patient outcome should be better. ’Not Q.’ Patient outcome is not better (for robotic surgery). ’Therefore, not P.’ Therefore, one should not do a more costly surgery (i.e. robotics). Is this argument valid? And is it sound? Validity means that a conclusion follows logically from the premises, whether or not the premises are true. The construct of this syllogism is a classical ‘Modus Tullens’ of propositional logic, and would be ‘valid’ since the conclusion follows from the two premises. Is it a sound argument, however? Soundness refers to an argument in which a conclusion is true AND the premises are true. Are the premises of this argument true? Currently, it has definitely been shown that robotic surgeries are more costly than regular laparoscopic approaches [5]. This cost differential may change as other robotic systems come on line in the future. We are most likely at the tip of the iceberg in terms of improving technology, enhanced competition, and streamlining of technique, with some more recent studies showing very similar costs per procedure to traditional laparoscopy [6]. What about premise 2, the outcome for patients? Studies are mixed with some showing equivalency to laparoscopy, and some showing slight improvement in outcome [7,8]. But what if the surgeons are unable or unwilling to perform the laparoscopic procedure (as has widely been the ca