Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Jul;24(7):721-730.
doi: 10.1007/s10151-020-02210-z. Epub 2020 Apr 22.

Cortical processing to anorectal stimuli after rectal resection with and without radiotherapy

S Haas  1   2 , P M Faaborg  3   4 , M Gram  5 , L Lundby  6   4 , C Brock  5 , A M Drewes  5   4 , S Laurberg  6   4 , K Krogh  7   4 , P Christensen  6   4
Affiliations

Cortical processing to anorectal stimuli after rectal resection with and without radiotherapy

S Haas et al. Tech Coloproctol. 2020 Jul.

Abstract

Background: Bowel dysfunction is common after surgery for rectal cancer, especially when neoadjuvant radiotherapy is used. The role of sensory function in the pathogenesis remains obscure, and the aim of the present study was to characterize the sensory pathways of the brain-gut axis in rectal cancer patients treated with resection ± radiotherapy compared with healthy volunteers.

Methods: Sensory evaluation by (neo)rectal distensions was performed and sensory evoked potentials (SEPs) were recorded during rapid balloon distensions of the (neo)rectum and anal canal in resected patients with (n = 8) or without (n = 12) radiotherapy. Twenty healthy volunteers were included for comparison. (Neo)rectal latencies and amplitudes of SEPs were compared and spectral band analysis from (neo)rectal and anal distensions was used as a proxy of neuronal processing.

Results: Neorectal sensation thresholds were significantly increased in both patient categories (all p < 0.008). There were no differences in (neo)rectal SEP latencies and amplitudes between groups. However, spectral analysis of (neo)rectal SEPs showed significant differences between all groups in all bands (all p < 0.01). On the other hand, anal SEP analyses only showed significant differences between the delta (0-4 Hz), theta (4-8 Hz) and, gamma 32-50 Hz) bands (all p < 0.02) between the subgroup of patients that also received radiotherapy and healthy volunteers.

Conclusions: Surgery for rectal cancer leads to abnormal cortical processing of neorectal sensation. Additional radiotherapy leads to a different pattern of central sensory processing of neorectal and anal sensations. This may play a role in the functional outcome of these patients.

Keywords: Evoked potentials; Functional; Radiotherapy; Rectal resection.

PubMed Disclaimer

References

    1. Mulsow J, Winter DC (2011) Sphincter preservation for distal rectal cancer—a goal worth achieving at all costs? World J. Gastroenterol 17(7):855–861 - DOI
    1. Scheer AS, Boushey RP, Liang S, Doucette S, O'Connor AM, Moher D (2011) The long-term gastrointestinal functional outcomes following curative anterior resection in adults with rectal cancer: a systematic review and meta-analysis. Dis Colon Rectum 54(12):1589–1597 - DOI
    1. Emmertsen KJ, Laurberg S (2008) Bowel dysfunction after treatment for rectal cancer. Acta Oncol 47(6):994–1003 - DOI
    1. Emmertsen KJ, Laurberg S (2012) Low anterior resection syndrome score: development and validation of a symptom-based scoring system for bowel dysfunction after low anterior resection for rectal cancer. Ann Surg 255(5):922–928 - DOI
    1. Peeters KC, van de Velde CJ, Leer JW, Martijn H, Junggeburt JM, Kranenbarg EK, Steup WH, Wiggers T, Rutten HJ, Marijnen CA (2005) "Late side effects of short-course preoperative radiotherapy combined with total mesorectal excision for rectal cancer: increased bowel dysfunction in irradiated patients—a Dutch colorectal cancer group study. J Clin Oncol 23(25):6199–6206 - DOI

Publication types

LinkOut - more resources