Caution is needed in interpreting the results of comparative studies regarding oncological operations by minimally invasive versus

We aim to alert the difference between groups while comparing studies of abdominal oncological operations performed either by minimally invasive or laparotomic approaches and potential conflicts of interest in presenting or interpreting the results. Considering the large volume of scientific articles that are published, there is a need to consider the quality of the scientific production that leads to clinical decision making. In this regards, it is important to take into account the choice of the surgical access route. Randomized, controlled clinical trials are the standard for comparing the effectiveness between these interventions. Although some studies indicate advantages in minimally invasive access, caution is needed when interpreting these findings. There is no detailed observation in each of the comparative study about the real limitations and potential indications for minimally invasive procedures, such as the indications for selected and less advanced cases, in less complex cavities, as well as its elective characteristic. Several abdominal oncological operations via laparotomy would not be plausible to be completely performed through a minimally invasive access. These cases should be carefully selected and excluded from the comparative group. The comparison should be carried out, in a balanced way, with a group that could also have undergone a minimally invasive access, avoiding bias in selecting those cases of minor complexity, placed in the minimally invasive group. It is not a question of criticizing the minimally invasive technologies, but of respecting the surgeon’s clinical decision regarding the most convenient method, revalidating the well-performed traditional laparotomy route, which has been unfairly criticized or downplayed by many people.

in minimally invasive approaches, but which can and should also be used in laparotomies.
Major bleeding in laparotomic surgeries, in the general reckoning of comparative studies, can represent situations of greater complexity that could not be solved by the minimally invasive route. In fact, when there are major hemorrhagic or other complex complications during a minimally invasive surgery, there is usually a disorderly conversion to "maximized" laparotomy surgery, sometimes with unfavorable outcomes 1 .

Bioethics in surgery A B S T R A C T A B S T R A C T
We aim to alert the difference between groups while comparing studies of abdominal oncological operations performed either by minimally invasive or laparotomic approaches and potential conflicts of interest in presenting or interpreting the results. Considering the large volume of scientific articles that are published, there is a need to consider the quality of the scientific production that leads to clinical decision making. In this regards, it is important to take into account the choice of the surgical access route. Randomized, controlled clinical trials are the standard for comparing the effectiveness between these interventions. Although some studies indicate advantages in minimally invasive access, caution is needed when interpreting these findings. There is no detailed observation in each of the comparative study about the real limitations and potential indications for minimally invasive procedures, such as the indications for selected and less advanced cases, in less complex cavities, as well as its elective characteristic. Several abdominal oncological operations via laparotomy would not be plausible to be completely performed through a minimally invasive access. These cases should be carefully selected and excluded from the comparative group. The comparison should be carried out, in a balanced way, with a group that could also have undergone a minimally invasive access, avoiding bias in selecting those cases of minor complexity, placed in the minimally invasive group. It is not a question of criticizing the minimally invasive technologies, but of respecting the surgeon's clinical decision regarding the most convenient method, revalidating the well-performed traditional laparotomy route, which has been unfairly criticized or downplayed by many people.
Keywords: Surgical Oncology. Selection Bias. Laparoscopy. Conversion to Open Surgery.

Surgeries initiated by minimally invasive
access and converted to laparotomy access due to some intraoperative limitation cannot be considered merely as one more procedure by laparotomy. This contaminates this group's statistics (crossover), because if they had been performed through laparotomic access from the beginning, the transoperative and, consequently, the postoperative outcomes could be different. In addition, one should consider the fact that it was not feasible to perform them through a minimally invasive access 2,3 .
The selection for minimally invasive surgeries is usually made up of less complex cases, even within the same oncological stage 2,4,5,6,7 . Patients at an earlier stage and with less comorbidity, the majority of those submitted to minimally invasive access, tend to have display outcomes, unlike the more complex and complicated ones, which are common in groups of patients submitted to laparotomic procedures 2,4,6,9 .
The lack of touch, in some situations of Perhaps, the heart of the matter is the choice of a more expensive and elective method at a disadvantage to the investment in access to fruitful assistance and cancer prevention to the majority of our needy receive either of the two interventions, randomization, control for biases and limitations) and systematic reviews that use rating scales to analyze methodological quality, free of conflicts of interest.
There is no demerit to those who continue performing highly complex oncological surgeries through an adequate laparotomic access.
population. Thus, "truths" such as incisions of adequate size, through technological access, with lower morbidity and early discharges may be secondary or more limited.