Original article: general thoracic
Adjuvant radiation therapy for stage II thymoma

https://doi.org/10.1016/S0003-4975(02)03828-6Get rights and content

Abstract

Background. Thymoma is difficult to study because of its indolent natural history. The criteria for administration of adjuvant radiation therapy remain controversial, and it is unclear whether patients with Masaoka stage II thymoma benefit from adjuvant radiation. The goal of this report was to determine whether or not this group benefits from radiation therapy in terms of disease-specific survival and tumor recurrence.

Methods. Case records of the Massachusetts General Hospital were retrospectively reviewed from 1972 to 1999. One hundred fifty-five patients underwent resection for thymoma, of which, 49 had stage II disease. The world literature was reviewed using a Medline search (1966 to 2001), and a secondary review of referenced works was performed.

Results. Fourteen stage II patients underwent radiation therapy. Thirty-five did not receive radiation therapy. Baseline prognostic factors between radiated and nonradiated groups were similar. All patients underwent complete resection. The addition of adjuvant radiotherapy did not significantly alter local or distant recurrence rates in stage II thymoma. Disease-specific survival at 10 years in stage II patients was 100% with radiotherapy and without radiotherapy (p = 0.87). There was one recurrence in the nonradiated group at 180 months, which was outside the usual radiation portal.

Conclusions. Most stage II patients do not require adjuvant radiation therapy and can be observed after complete resection.

Section snippets

Patient population and follow-up

After approval from the Institutional Review Board, the surgical logs and pathology files at the Massachusetts General Hospital were retrospectively reviewed between 1972 and 1999. One hundred fifty-five patients underwent thymoma resection. Of these, 49 had stage II disease and form the basis for this report. Hospital and office medical records were reviewed, and demographic and tumor-related data were entered into a computerized database. Patient follow-up was obtained by review of hospital

Results

The median age at diagnosis was 56 years (range, 13 to 82 years). Twenty-seven (55%) patients were male. Sixteen patients (32.7%) had myasthenia gravis. There were no significant demographic differences between radiated and nonradiated patients.

Surgery was offered as initial treatment to all patients. Seven surgeons performed thymoma resection with total thymectomy via median sternotomy. All 49 patients with stage II disease underwent complete resection, with negative microscopic margins.

Comment

The most important determinants of long-term survival in thymoma are completeness of resection [11], Masaoka stage [15], and Mueller-Hermelink histologic classification 16, 17, 18, 19, 20. The prognostic importance of these determinants has been verified in several large studies. Unfortunately, recommendations for the appropriate use of adjuvant radiation therapy for stage II thymoma are wide ranging and controversial. Current recommendations advocate radiation of all patients with stage II

References (33)

  • E. Ruffini et al.

    Recurrence of thymomaanalysis of clinicopathologic features, treatment and outcome

    J Thorac Cardiovasc Surg

    (1997)
  • A. Boonen et al.

    Thymoma-associated systemic lupus erythematosus, exacerbating after thymectomya case report and review of the literature

    Rheumatology

    (2000)
  • K.B. Wilkins et al.

    Clinical and pathologic predictors of survival in patients with thymoma

    Ann Surg

    (1999)
  • J.S. Welsh et al.

    Association between thymoma and second neoplasms

    JAMA

    (2000)
  • W.J. Curran et al.

    Invasive thymomathe role of mediastinal irradiation following complete or incomplete surgical resection

    J Clin Oncol

    (1988)
  • J.B. Krueger et al.

    Stage III thymomaresults of postoperative radiation therapy

    Radiology

    (1988)
  • Cited by (112)

    • Thymic epithelial tumors. Thymoma

      2021, Medicine (Spain)
    • Thymic tumors and results of radiotherapy

      2018, Reports of Practical Oncology and Radiotherapy
    • Survival Impact of Adjuvant Radiation Therapy in Masaoka Stage II to IV Thymomas: A Systematic Review and Meta-analysis

      2016, International Journal of Radiation Oncology Biology Physics
      Citation Excerpt :

      Postoperative RT in stage I thymomas is unlikely to offer improved treatment outcomes (25). Some researchers do not recommend adjuvant management in completely resected stage II (26-29), but the determination of PORT indication has been a controversial topic. Given the well-localized tumor characteristics of stage II disease, good local tumor control has been achievable with complete surgical resection.

    • Judge a man by his questions rather than his answers

      2016, Journal of Thoracic and Cardiovascular Surgery
    View all citing articles on Scopus
    View full text