Is thymomectomy equivalent to complete thymectomy in non-myasthenic patients with early-stage thymoma?

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed is whether thymomectomy can be equivalent to thymectomy for non-myasthenic early-stage thymoma in terms of recurrence and survival. Ten papers were chosen to answer the question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers were tabulated. All studies included in this analysis are retrospective; most of them are small and from single-institution experiences, and only 3 used propensity-matched analysis to minimize the patients' selection bias. The choice of performing thymectomy or thymomectomy was based on surgeons' preference rather than on a standardized surgical approach. Most papers found that thymectomy was equivalent to thymomectomy in terms of outcomes, but these results could be affected by the intergroup differences in terms of follow-up length, administration of induction or adjuvant therapy, histological subtypes distribution and tumour size. Conversely, the studies of the Japanese Association for Research on the Thymus and the Chinese Alliance for Research in Thymoma found a higher rate of local recurrence in the thymomectomy group than in the thymectomy group. The National Comprehensive Cancer Network, National Cancer Institute and International Thymic Malignancy Interest Group recommend complete thymectomy in non-myasthenic patients with early thymoma; therefore, the identified studies in this review are not strong enough to change this recommendation.