Yes, it is a general answer without knowing the background scenario. I’m sorry if I made a mistake. In general, I think the criteria for decision making should not be based on a prognostic model from an observational study, but on a RCT that demonstrates the safety & efficacy of carrying out or sparing the intervention. A prognostic model would allow stratifying individuals, but given that outcomes are conditioned to the intervention, a prognostic model can be used to define better eligibility criteria that requires validation in a RCT. As far as I know, a prognostic model based on an observational study should not in itself guide that decision making. In my opinion, this is a mistake. For example, it is believed that subjects with low-risk febrile neutropenia treated with high levels of supportive care may be given reduced support, but clinicians do not worry that this may increase their risk. When deciding on admission to the ICU, it is considered that those with a high risk of death should not be admitted, but it is not taken into account that the mortality on the normal hospitalization ward will be even higher. The literature is full of similar examples. The problem is the observational nature of the studies, not taking into account interactions or not testing the new criteria for stratification in RCTs. In your specific case, you cannot assume that a low probability of lymph node involvement after radical surgery is similar to a low probability of long-term local recurrence in absence of that surgery. For this reason, you cannot assume that lymphadenectomy is not critical to prevent relapse even in the low-risk group, nor can you predict what would happen to high-risk subjects if they did not have the surgery.
As you can see in the paper by Giuliano (above), the criteria for not operating is based on disease-free survival in a RCT with 10 years follow-up. The end point ‘number of positive nodes’ is just a surrogate variable, whose prognostic value depends on the background knowledge of each disease, but cannot be directly inferred or assimilated with a survival end point.