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Patterns of Failure Using a Conformal Radiation Therapy Tumor Bed Boost for
Medulloblastoma
Suzanne L. Wolden, Ira J. Dunkel, Mark
M. Souweidane, Laura Happersett, Yasmin Khakoo,
Karen Schupak, David Lyden, Steven A. Leibel
From the Departments of Radiation Oncology, Pediatrics, and
Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY. Address reprint requests to Suzanne L. Wolden, MD,
Department of Radiation Oncology, 1275 York Ave, Box 22, New York, NY 10021;
email: woldens@mskcc.org.
Purpose. To assess the patterns of failure for patients with
medulloblastoma receiving a conformal tumor bed boost rather than
a boost to the entire posterior fossa.
Patients and Methods. From 1994 to 2002, 32 consecutive
patients with newly diagnosed medulloblastoma treated at Memorial
Sloan-Kettering Cancer Center (New York, NY) received a conformal
boost to the tumor bed in conjunction with craniospinal radiation
therapy.
Twenty-eight patients also received chemotherapy.
The median
age was 9 years (range, 3 to 34 years), and the male to female ratio
was 3:1.
Twenty-seven patients had standard-risk disease, and five
patients had high-risk disease.
Craniospinal doses ranged from 23.4
to 39.6 Gy, and total tumor bed doses ranged from 54 to 59.4 Gy. Results. With a median follow-up of 56 months, six patients
have relapsed; five relapsed outside of the posterior fossa, and
one failed within the posterior fossa, outside of the high-dose boost
volume.
Five-year actuarial disease-free and overall survival rates
were 84% and 85%, respectively.
Freedom from posterior fossa failure
was 100% and 86% at 5 and 10 years, respectively.
Freedom from
distant failure was 84% at 5 years, with a trend for improvement when
full-dose craniospinal radiation (36 to 39.6 Gy) was used compared
with a reduced dose (23.4 Gy) of radiation (100% v 63%,
respectively; P = .06).
No other predictive variables were
identified. Conclusion. Conformal treatment to the tumor bed allows for
significant sparing of critical structures.
The posterior fossa failure
rate in this series is similar to that reported when the entire
posterior fossa is treated.
This approach should be investigated
further in a phase III trial.
© 2003 American Society for
Clinical Oncology
Source: http://www.jco.org/cgi/content/abstract/21/16/3079
HTML Full Text: http://www.jco.org/cgi/content/full/21/16/3079
PDF Full Text: http://www.jco.org/cgi/reprint/21/16/3079
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