Comparison of pathological complete response rates after neoadjuvant short-course radiotherapy or chemoradiation followed by delayed surgery in locally advanced rectal cancer

• Published in: European journal of surgical oncology 2018-07, Vol.44 (7), p.1013-1017
• Main Authors: Hoendervangers, Sieske, Couwenberg, Alice M., Intven, Martijn P.W., van Grevenstein, Wilhelmina M.U., Verkooijen, Helena M.
• Format: Article
• Language: English
• Subjects: Chemoradiation; Locally advanced rectal cancer; Pathological complete response; Short course radiotherapy
• ISSN: 0748-7983; 1532-2157
• DOI: 10.1016/j.ejso.2018.03.014

Patients with locally advanced rectal cancer (LARC) who are unfit for chemoradiation (CRT), are often offered short-course radiotherapy followed by delayed surgery (SCRT-delay). This entails a lower radiation dose, no chemotherapy and a shorter treatment period. This may lower their chances for complete tumor response and, as such, organ-sparing approaches. The purpose of this study was to compare the pathological complete response (pCR) rates between neoadjuvant CRT and SCRT-delay in patients with LARC in a nationwide database from the Netherlands. In the population based Netherlands Cancer Registry, clinical stage III rectal cancer patients, diagnosed between 2008 and 2014, who underwent CRT or SCTR-delay were selected. pCR (ypT0N0), near pCR (ypT0-1N0), and tumor and nodal downstaging were compared between the treatment groups using multivariable logistic regression analysis. 386 patients underwent SCRT-delay and 3659 patients underwent CRT. The pCR-rate in the SCRT-delay group was significantly lower compared to the CRT-group (6.4% vs. 16.2%, p