One of the most difficult clinical questions for both MG patients and physicians is how to predict whether adult patients with oculomotor MG will convert to systemic MG, which has not yet been fully determined due to the relative rarity of MG and the lack of prospective studies. Some retrospective studies have shown that the transition from oculomotor MG to systemic MG occurs mostly within 2 years of disease onset, but the risk factors for this transition have not been clarified, and it is inconclusive whether the use of immunosuppressive drugs prevents this transition. Some studies have shown that the rate of progression to the systemic form is lower in patients using hormones than in those using cholinesterase inhibitors alone, which seems to suggest that early diagnosis and treatment can help reduce the likelihood of conversion from oculomotor to systemic form, but these nonrandomized studies have too many confounding factors to draw substantial conclusions. These confounding factors include the duration of oculomotor disease, serologic parameters, and hormone dosage, whereas in a retrospective study of 2,000 patients, the rate of conversion of oculomotor to systemic forms was essentially constant between 1940 and 2000, another indication that additional immunosuppressive interventions do not change the status quo. The EPITOME study, initiated in 2012 with the aim of answering this question, has so far enrolled insufficient patients to proceed. Preliminary results of the ‘ROG’ scale used by UK experts to predict the likelihood of conversion of oculomotor type to systemic type were communicated and reported at the 2015 British Annual Neurology Meeting, where the main risk factors included thymic hyperplasia, seropositivity, and co-morbid other autoimmune disorders, and patients possessing these factors were significantly more likely to develop systemic Patients with these factors are significantly more likely to develop systemic MG. Autoimmune diseases such as MG are very complex, and further data from prospective randomized studies are needed to clarify many aspects of the transition from oculomotor to systemic forms!