Cited by 37Mathematical Biology Tumor GrowthEffects of Radiation ExposureRadiation Therapy and Dosimetry

Three endpoints of in vivo tumour radiobiology and their statistical estimation

Open access
Demidenko, Eugene·2010·International Journal of Radiation Biology

Abstract

PURPOSE: To review the existing endpoints of tumour growth delay assays in experimental radiobiology with an emphasis on their efficient estimation for statistically significant identification of the treatment effect. To mathematically define doubling time (DT), tumour-growth delay (TGD) and cancer-cell surviving fraction (SF) in vivo using exponential growth and regrowth models with tumour volume measurements obtained from animal experiments. MATERIALS AND METHODS: A statistical model-based approach is used to define and efficiently estimate the three endpoints of tumour therapy in experimental cancer research. RESULTS: The log scale is advocated for plotting the tumour volume data and the respective analysis. Therefore, the geometric mean should be used to display the mean tumour volume data, and the group comparison should be a t-test for the log volume to comply with the Gaussian-distribution assumption. The relationship between cancer-cell SF, TGD and rate of growth is rigorously established. The widespread formula for cell kill is corrected; it has been rigorously shown that TGD is the difference between DTs. The software for the tumour growth delay analysis based on the mixed modeling approach with a complete set of instructions and example can be found on the author's webpage. CONCLUSIONS: The existing practice for TGD data analysis from animal experiments suffers from imprecision and large standard errors that yield low power and statistically insignificant treatment effect. This practice should be replaced with a model-based statistical analysis on the log scale.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.3109/09553000903419304

Cites

30 of 30 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • The combination of palbociclib and cetuximab was proposed as a potential strategy to overcome cetuximab resistance by targeting cyclin D1 deregulation.

    “The combination of the CDK4/6 inhibitor palbociclib and the EGFR inhibitor cetuximab was proposed as a potential strategy to overcome cetuximab resistance by targeting cyclin D1 deregulation (28).”

    From Statistical Assessment of Drug Synergy from <i>In Vivo</i> Combination Studies Using Mouse Tumor Models (2023) · cites this paper as [28]

    The Introduction and Discussion describe statistical estimation of tumour-treatment endpoints, while the photodynamic radiotherapy example concerns a mouse prostate-tumour model. Searches for palbociclib, cetuximab resistance, and cyclin D1 found no passage addressing the proposed combination or its rationale in our copy. (LLM, conf=0.78)

    Experimental — accuracy not yet measured

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

1 of the 31 references couldn’t be matched to a known paper.

Research works printed but not linked: 1

  1. Hall EJ Radiobiology for the radiobiologist 2000 5th ed. Philadelphia Lippincott

Cited by

Sorted by citations

Authors
Demidenko, E.
Affiliations
Dartmouth College (US)
Corresponding author
Demidenko, Eugene
Venue
International Journal of Radiation Biology
Published
2010-02
Volume
86
Issue
2
Pages
164-173
ISSN
  • 0955-3002 (ISSN-L)
  • 1362-3095
OpenAlex
W2135761571
Cited by
37
References
31
Citations by year
2026: 2 · 2025: 2 · 2024: 2 · 2023: 5 · 2021: 4 · 2020: 3 · 2019: 3 · 2018: 1 · 2017: 5 · 2016: 2 · 2015: 3 · 2013: 2 · 2012: 1
FWCI
1.37
Type
journal article
Language
en
Open access
Locations
  • International Journal of Radiation Biology (publishedVersion)
  • PubMed (publishedVersion)
  • PubMed Central (acceptedVersion)
Funders
  • National Institutes of Health
  • National Cancer Institute (R01CA130880, P30CA023108)
Topics
  • Physical Sciences › Mathematics › Modeling and Simulation › Mathematical Biology Tumor Growth
  • Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Effects of Radiation Exposure
  • Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Radiation Therapy and Dosimetry
Keywords
tumour growth delay, tumor doubling time, surviving fraction, tumor regrowth, exponential growth model, geometric mean, mixed modeling, statistical power, tumor volume
MeSH terms
Animals, Cell Survival, Models, Biological, Neoplasms, Experimental, Photochemotherapy, Radiobiology, Models, Statistical, Endpoint Determination

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review