The role of radiation therapy in the management of craniopharyngioma: a 25-year experience and review of the literature

Abstract

Purpose: To review the outcome and quality of life at 5 years and more of 37 children treated with radiation therapy combined or not with surgical resection for a craniopharyngioma in a single institution.

Methods and materials: From January 1969 through December 1992, 37 children received external therapy at the Institut Gustave Roussy (Villejuif, France). Age ranged between 1 and 15 years (mean 7.4), M/F sex ratio was 0.76. In approximately one-half of the cases (18/37), radiation therapy was applied in conjunction with a surgical resection, and in almost one-half of the cases (18/37) as part of a salvage program following local failure. Total dose ranged between 45 and 56 Gy (median 50) given with a conventional fractionation in most children. Survival (S), event-free survival (EFS) were computerized according to the Kaplan-Meier method and prognostic factors for local failure and functional status analyzed. Functional outcome was evaluated according to the Wen score in 4 grades (gr 1: normal with/without hormonal replacement, gr 4: totally dependent, gr 2 and 3: intermediate disabilities).

Results: At the time of analysis, 24 children (65%) were alive with NED, 4 (11%) alive after failure, and 9 (24%) dead of various causes. Following therapy, S and EFS regularly degraded and didn't seem to reach a plateau before 9 years (5 and 10 year S and EFS, respectively, 91, 65, and 78 and 56.5%). This was due to the occurrence of late failures (5 and 8.5 years) and late lethal complications (1 in-field glioblastoma multiforme at 9 years). A significant gain on EFS followed the introduction of modern imaging (p = 0.03), the association of surgical resection with RT (p = 0.01) and of higher doses of radiation superior or equal to 55 Gy (p = 0.05); a similar gain on S was observed in patients with a good initial performance status (p = 0.05). It is remarkable that surgical salvage of local failures following RT could induce prolonged remission in 4 children. Functional outcome was impaired in all but 5 children out of 35 fully evaluable (86%) and related with the initial symptomatology and/or therapy. Endocrinological, visual, neurological functions were affected in 97, 34, and 40%, respectively. It appeared correlated with the initial performance status (p = 0.02) and possibly with a younger age at treatment (p = 0.07).

Conclusions: Long-term follow-up beyond 5 years is warranted in craniopharyngioma to assess tumor control and functional outcome after radiation therapy. Although this therapeutical modality provides a high cure rate alone or in combination with surgery and even though at the time of failure, further strategies should aim to limit the severe toxicity (i.e., Wen gr 3 + 4) that was observed in more than one-third of our patients.