title: Long-term outcome and factors influencing the outcome of thymectomy for myasthenia gravis.
abstract: Thymectomy has gained widespread acceptance as a treatment for patients with myasthenia gravis (MG). Patients with myasthenia gravis who had undergone thymectomy by extended transsternal approach between 1981 and 1987 were retrospectively reviewed to evaluate the result of thymectomy, time to remission, time to maximum improvement and factors influencing remission after thymectomy. There were 128 patients, 45 men and 83 women and the mean ages at the time of thymectomy were 35.7 and 32.2 years respectively. After thymectomy, 41.2% of the patients were in remission, 53% improved and 5.8% had no response. The remission rates at 1, 2, 5 and 10 years after thymectomy were 9%, 17%, 37% and 53% respectively and the median time to remission was 9 years. The maximum improvement rates at 1, 2, 5 and 10 years after thymectomy were estimated to be 30%, 40%, 57% and 78% respectively and the median time to maximum improvement was 3.6 years. Patients with ocular MG, longer duration of symptoms before thymectomy and atrophic thymus gland appeared to take longer to achieve remission although none of the factors was significantly associated with the time to remission. Thymectomy is beneficialfor MG patients with satisfactory remission and improvement rates. It is recommended that thymectomy should be advocatedfor these patients early in the course of the disease because the duration of the symptoms appeared to be the main determinant of the outcome.
authors.affiliation: Division of Neurology, Department of Medicine, Ramathibodi Hospital, Rama 6 Road, Bangkok 10400, Thailand. rarwt@mahidol.ac.th
authors.forename: Rawiphan
authors.initials: R
authors.lastname: Witoonpanich
authors.forename: Charungthai
authors.initials: C
authors.lastname: Dejthevaporn
authors.forename: Theerayuth
authors.initials: T
authors.lastname: Srisinroongruang
authors.forename: Wises
authors.initials: W
authors.lastname: Subhannachart
authors.forename: Sukasom
authors.initials: S
authors.lastname: Attanavanich
authors.forename: Somboon
authors.initials: S
authors.lastname: Boonkasem
authors.forename: Ammarin
authors.initials: A
authors.lastname: Thakkinstian
mesh_terms: D000328:Adult; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009157:Myasthenia Gravis / Q000601:surgery*; D012074:Remission Induction; D012189:Retrospective Studies; D013934:Thymectomy; D013997:Time Factors; D016896:Treatment Outcome