Dataset Information

Growth dynamics of untreated glioblastomas in vivo.

ABSTRACT:

Background

Glioblastomas are primary malignant brain tumors with a dismal prognosis. Knowledge of growth rates and underlying growth dynamics is useful for understanding basic tumor biology, developing realistic tumor models, and planning treatment logistics.

Methods

By using repeated pretreatment contrast-enhanced T1-weighted MRI scans from 106 patients (aged 26-83 years), we studied the growth dynamics of untreated glioblastomas in vivo. Growth rates were calculated as specific growth rates and equivalent volume doubling times. The fit of different possible growth models was assessed using maximum likelihood estimations.

Results

There were large variations in growth rates between patients. The median specific growth rate of the tumors was 1.4% per day, and the equivalent volume doubling time was 49.6 days. Exploring 3 different tumor growth models showed similar statistical fit for a Gompertzian growth model and a linear radial growth model and worse fit for an exponential growth model. However, large tumors had significantly lower growth rates than smaller tumors, supporting the assumption that glioblastomas reach a plateau phase and thus exhibit Gompertzian growth.

Conclusion

Based on the fast growth rate of glioblastoma shown in this study, it is evident that poor treatment logistics will influence tumor size before surgery and can cause significant regrowth before adjuvant treatment. Since there is a known association between tumor volume, extent of surgical resection, and response to adjuvant therapy, it is likely that waiting times play a role in patient outcomes.

SUBMITTER: Stensjoen AL

PROVIDER: S-EPMC4578579 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Publications

Growth dynamics of untreated glioblastomas in vivo.

Stensjøen Anne Line AL Solheim Ole O Kvistad Kjell Arne KA Håberg Asta K AK Salvesen Øyvind Ø Berntsen Erik Magnus EM

Neuro-oncology 20150310 10

<h4>Background</h4>Glioblastomas are primary malignant brain tumors with a dismal prognosis. Knowledge of growth rates and underlying growth dynamics is useful for understanding basic tumor biology, developing realistic tumor models, and planning treatment logistics.<h4>Methods</h4>By using repeated pretreatment contrast-enhanced T1-weighted MRI scans from 106 patients (aged 26-83 years), we studied the growth dynamics of untreated glioblastomas in vivo. Growth rates were calculated as specific ...[more]

PMID: 25758748

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Dataset Information

Growth dynamics of untreated glioblastomas in vivo.

Background

Methods

Results

Conclusion

Publications

Growth dynamics of untreated glioblastomas in vivo.

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