Long-term evaluation of extended thymectomy with anterior mediastinal dissection for myasthenia gravis

Background. Thymectomy for the treatment of myasthenia gravis (MG) is well established. The extent Of resection, however; remains a source for debate. Outcomes for newer surgical techniques need to be compared to more extensi ve procedures. Methods. A retrospective review was done of 64 consecutive patients who und erwent transsternal thymectomy with extended anterior mediastinal dissectio n for MG between 1979 and 2000 and who were operated on by a single surgeon . Results. Fifty-six patient charts were available, providing 58 operative pr ocedures. Three patients had died of unrelated causes. The mean age of symp tom onset was 36.0 +/- 2.5 years, with a mean duration of 3.3 +/- 0.5 years until surgery was undertaken. The mean length of follow-up was 69.8 +/- 0. 8 years. Operative procedures were associated with a 10.3% major morbidity rate and no mortality. Drug five remission was achieved in 50.0% of the pat ients, and symptoms were absent or improved in 76.8% of the patients. Patie nts followed zip long-term (> 10 years) achieved the greatest remission rat e (71.4%) and symptomatic improvement (85.7%). After thymectomy, the mean d osages of prednisone and Mestinon decreased by 69.3% and 58.8%, respectivel y. Conclusions. Extended thymectomy provides excellent overall symptom improve ment, which is enhanced over time. This re-view provides a basis for long-t erm comparison with other less invasive and perhaps less extensive procedur es.