The hazard of accelerated tumor clonogen repopulation during radiotherapy
Paper cited by one technology page, indexed on Europe PMC as PubMed record 3390344 and published in Acta oncologica; the citing page links this DOI, which is how the record was matched.
Overview
When analysis of results of radiotherapy for nearly 500 patients with oropharyngeal cancer showed evidence for rapid tumor regrowth during extensions of treatment from about 5 weeks to about 8 weeks, we searched the literature on radiotherapy for head and neck cancer to determine whether it revealed similar evidence of accelerated tumor regrowth. Estimates of doses to achieve local control in 50% of cases (TCD50) were made from published local control rates, and the dependence of these doses on overall treatment duration was evaluated. In parallel, published scattergrams were analyzed to estimate the rate of tumor regrowth over the period of 4-10 weeks from initiation of therapy. Both analyses suggested that, on average, clonogen repopulation in squamous cell carcinomas of the head and neck accelerates only after a lag period of the order of 4 +/- 1 weeks after initiation of radiotherapy and that a dose increment of about 0.6 Gy per day is required to compensate for this repopulation. Such a dose increment is consistent with a 4-day clonogen doubling rate, compared with a median of about 60 days in published reports of unperturbed tumor growth rates. The values presented here are average values for a large number of patients: it is necessary, not only to verify the results of these retrospective analyses in prospective studies, but also to develop methods to predict the time of onset and rate of accelerated tumor clonogen repopulation in the individual patient.
Indexed on Europe PMC as PubMed record 3390344 (DOI 10.3109/02841868809090333). Matched by DOI alone: one technology page cites this DOI among its external links (the pages are listed under Related), and this page was written so that the citation resolves inside OnCo. No figure has been checked by an editor.
One technology page on OnCo cites this paper by its DOI; this record gives the citation a page of its own so a reader can follow it without leaving OnCo. Read the abstract above alongside the citing page listed under Related; the record was created automatically from the Europe PMC entry and its figures have not been checked by hand.
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