Temporal determinants of tumour response to neoadjuvant rectal radiotherapy.

<h4>Introduction</h4>In locally advanced rectal cancer, longer delay to surgery after neoadjuvant radiotherapy increases the likelihood of histopathological tumour response. Chronomodulated radiotherapy in rectal cancer has recently been reported as a factor increasing tumour response to...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Kendrick Koo, Rachel Ward, Ryan L Smith, Jeremy Ruben, Peter W G Carne, Hany Elsaleh
Formato:	article
Lenguaje:	EN
Publicado:	Public Library of Science (PLoS) 2021
Materias:	Medicine R Science Q
Acceso en línea:	https://doaj.org/article/96dd169f25c34797a2611dcab2aeed7d
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:96dd169f25c34797a2611dcab2aeed7d
record_format	dspace
spelling	oai:doaj.org-article:96dd169f25c34797a2611dcab2aeed7d2021-12-02T20:15:41ZTemporal determinants of tumour response to neoadjuvant rectal radiotherapy.1932-620310.1371/journal.pone.0254018https://doaj.org/article/96dd169f25c34797a2611dcab2aeed7d2021-01-01T00:00:00Zhttps://doi.org/10.1371/journal.pone.0254018https://doaj.org/toc/1932-6203<h4>Introduction</h4>In locally advanced rectal cancer, longer delay to surgery after neoadjuvant radiotherapy increases the likelihood of histopathological tumour response. Chronomodulated radiotherapy in rectal cancer has recently been reported as a factor increasing tumour response to neoadjuvant treatment in patients having earlier surgery, with patients receiving a larger proportion of afternoon treatments showing improved response. This paper aims to replicate this work by exploring the impact of these two temporal factors, independently and in combination, on histopathological tumour response in rectal cancer patients.<h4>Methods</h4>A retrospective review of all patients with rectal adenocarcinoma who received long course (≥24 fractions) neoadjuvant radiotherapy with or without chemotherapy at a tertiary referral centre was conducted. Delay to surgery and radiotherapy treatment time were correlated to clinicopathologic characteristics with a particular focus on tumour regression grade. A review of the literature and meta-analysis were also conducted to ascertain the impact of time to surgery from preoperative radiotherapy on tumour regression.<h4>Results</h4>From a cohort of 367 patients, 197 patients met the inclusion criteria. Complete pathologic response (AJCC regression grade 0) was seen in 46 (23%) patients with a further 44 patients (22%) having at most small groups of residual cells (AJCC regression grade 1). Median time to surgery was 63 days, and no statistically significant difference was seen in tumour regression between patients having early or late surgery. There was a non-significant trend towards a larger proportion of morning treatments in patients with grade 0 or 1 regression (p = 0.077). There was no difference in tumour regression when composite groups of the two temporal variables were analysed. Visualisation of data from 39 reviewed papers (describing 27379 patients) demonstrated a plateau of response to neoadjuvant radiotherapy after approximately 60 days, and a meta-analysis found improved complete pathologic response in patients having later surgery.<h4>Conclusions</h4>There was no observed benefit of chronomodulated radiotherapy in our cohort of rectal cancer patients. Review of the literature and meta-analysis confirms the benefit of delayed surgery, with a plateau in complete response rates at approximately 60-days between completion of radiotherapy and surgery. In our cohort, time to surgery for the majority of our patients lay along this plateau and this may be a more dominant factor in determining response to neoadjuvant therapy, obscuring any effects of chronomodulation on tumour response. We would recommend surgery be performed between 8 and 11 weeks after completion of neoadjuvant radiotherapy in patients with locally advanced rectal cancer.Kendrick KooRachel WardRyan L SmithJeremy RubenPeter W G CarneHany ElsalehPublic Library of Science (PLoS)articleMedicineRScienceQENPLoS ONE, Vol 16, Iss 6, p e0254018 (2021)
institution	DOAJ
collection	DOAJ
language	EN
topic	Medicine R Science Q
spellingShingle	Medicine R Science Q Kendrick Koo Rachel Ward Ryan L Smith Jeremy Ruben Peter W G Carne Hany Elsaleh Temporal determinants of tumour response to neoadjuvant rectal radiotherapy.
description	<h4>Introduction</h4>In locally advanced rectal cancer, longer delay to surgery after neoadjuvant radiotherapy increases the likelihood of histopathological tumour response. Chronomodulated radiotherapy in rectal cancer has recently been reported as a factor increasing tumour response to neoadjuvant treatment in patients having earlier surgery, with patients receiving a larger proportion of afternoon treatments showing improved response. This paper aims to replicate this work by exploring the impact of these two temporal factors, independently and in combination, on histopathological tumour response in rectal cancer patients.<h4>Methods</h4>A retrospective review of all patients with rectal adenocarcinoma who received long course (≥24 fractions) neoadjuvant radiotherapy with or without chemotherapy at a tertiary referral centre was conducted. Delay to surgery and radiotherapy treatment time were correlated to clinicopathologic characteristics with a particular focus on tumour regression grade. A review of the literature and meta-analysis were also conducted to ascertain the impact of time to surgery from preoperative radiotherapy on tumour regression.<h4>Results</h4>From a cohort of 367 patients, 197 patients met the inclusion criteria. Complete pathologic response (AJCC regression grade 0) was seen in 46 (23%) patients with a further 44 patients (22%) having at most small groups of residual cells (AJCC regression grade 1). Median time to surgery was 63 days, and no statistically significant difference was seen in tumour regression between patients having early or late surgery. There was a non-significant trend towards a larger proportion of morning treatments in patients with grade 0 or 1 regression (p = 0.077). There was no difference in tumour regression when composite groups of the two temporal variables were analysed. Visualisation of data from 39 reviewed papers (describing 27379 patients) demonstrated a plateau of response to neoadjuvant radiotherapy after approximately 60 days, and a meta-analysis found improved complete pathologic response in patients having later surgery.<h4>Conclusions</h4>There was no observed benefit of chronomodulated radiotherapy in our cohort of rectal cancer patients. Review of the literature and meta-analysis confirms the benefit of delayed surgery, with a plateau in complete response rates at approximately 60-days between completion of radiotherapy and surgery. In our cohort, time to surgery for the majority of our patients lay along this plateau and this may be a more dominant factor in determining response to neoadjuvant therapy, obscuring any effects of chronomodulation on tumour response. We would recommend surgery be performed between 8 and 11 weeks after completion of neoadjuvant radiotherapy in patients with locally advanced rectal cancer.
format	article
author	Kendrick Koo Rachel Ward Ryan L Smith Jeremy Ruben Peter W G Carne Hany Elsaleh
author_facet	Kendrick Koo Rachel Ward Ryan L Smith Jeremy Ruben Peter W G Carne Hany Elsaleh
author_sort	Kendrick Koo
title	Temporal determinants of tumour response to neoadjuvant rectal radiotherapy.
title_short	Temporal determinants of tumour response to neoadjuvant rectal radiotherapy.
title_full	Temporal determinants of tumour response to neoadjuvant rectal radiotherapy.
title_fullStr	Temporal determinants of tumour response to neoadjuvant rectal radiotherapy.
title_full_unstemmed	Temporal determinants of tumour response to neoadjuvant rectal radiotherapy.
title_sort	temporal determinants of tumour response to neoadjuvant rectal radiotherapy.
publisher	Public Library of Science (PLoS)
publishDate	2021
url	https://doaj.org/article/96dd169f25c34797a2611dcab2aeed7d
work_keys_str_mv	AT kendrickkoo temporaldeterminantsoftumourresponsetoneoadjuvantrectalradiotherapy AT rachelward temporaldeterminantsoftumourresponsetoneoadjuvantrectalradiotherapy AT ryanlsmith temporaldeterminantsoftumourresponsetoneoadjuvantrectalradiotherapy AT jeremyruben temporaldeterminantsoftumourresponsetoneoadjuvantrectalradiotherapy AT peterwgcarne temporaldeterminantsoftumourresponsetoneoadjuvantrectalradiotherapy AT hanyelsaleh temporaldeterminantsoftumourresponsetoneoadjuvantrectalradiotherapy
_version_	1718374542401863680

Temporal determinants of tumour response to neoadjuvant rectal radiotherapy.

Ejemplares similares