Thirteen years follow-up after radical transsternal thymectomy for myasthenia gravis. Do short-term results predict long-term outcome?

OBJECTIVE: Long-term evaluation of efficacy and quality of life after radical surgical approach for myasthenia gravis (MG). Comparison between short-term follow-up and long-term outcome.

METHODS: All patients (n=26, 16 men and 10 women, mean age: 40.7 years) underwent total transsternal thymectomy for MG between 1986 and 1989. Prospective analysis of the patients for short-term follow-up (mean 22.4 months) was published in 1991. The same group of patients was reevaluated in 2001 (range of follow-up 11.4-15.2 years) and assessed according to the classification of Osserman and Oosterhuis.

RESULTS: Mean follow-up was 13.0 years (range 11.4-15.2 years). Two patients were lost from follow-up and one died 4 years after thymectomy for reasons unrelated to MG (n=23). No early or late postoperative mortality was observed. One sternal osteomyelitis occurred. Late postoperative morbidity included sternal instabilities (n=2), mild residual thoracic pain (n=6), and hypertrophic scars (n=7). Five patients were rehospitalized for aggravating MG and needed plasmapheresis (n=3) and intubation (n=1). Thirteen patients (56.5%) showed objective clinical improvement, including six patients (26.1%) with complete remission. Eleven patients (47.8%) do not take any medication at all. Because some late relapse may occur several years after operation, the rate of improvement decreased slightly, whereas the difference between short and long-term follow-up was not statistically significant (P=0.405). Twenty patients (87%) returned to work, including part-time occupation (n=4). Fourteen patients (61%) are performing sports regularly.

CONCLUSIONS: Our data confirm that radical, transsternal thymectomy is an effective and safe therapeutic modality for MG. Short-term results seem to deteriorate over time, therefore long-term studies for minimally invasive approaches have to prove equal results before replacing the standard procedure.