Novel method may reduce adverse effects of rectal cancer treatment

Researchers from Karolinska Institute (Stockholm, Sweden) have demonstrated promising results for combining short course pre-operative radiotherapy followed by delayed surgery to treat rectal cancer.

The study recently published in The Lancet Oncology, describes how this method has fewer adverse side effects than standard rectal cancer surgery without compromising efficacy.

Annually, approximately 2000 men and women are affected by rectal cancer in Sweden. In the early 1990’s preoperative radiotherapy was introduced, leading to improved prognoses with a reduced risk of local recurrence for patients with rectal cancer.

However, due to the adverse reactions associated with radiotherapy, the optimal radiotherapy fractionation and the interval between it and the subsequent surgery has been a topic for debate. In this study, the researchers aimed to establish if the adverse effects associated with rectal cancer treatment can be reduced by increasing the duration of the course of radiation whilst administering lower doses or by increasing the time between radiation and surgery.

Rectal cancer patients were randomly allocated to one of three treatment arms; standard therapy (short-course (5×5 Gy) radiotherapy with direct surgery within a week), delayed surgery with short-course (5×5 Gy) radiotherapy followed by surgery after 4-8 weeks), or delayed surgery with long-course (25×2 Gy) radiotherapy followed by surgery after 4-8 weeks).

The results demonstrated that patients in the delayed surgery groups developed less clinical complications with similar oncological outcomes as the standard therapy group. They also discovered that there was no difference between short or long course radiotherapy apart from the longer course extending the treatment time.

“The results of the study will give rise to improved therapeutic strategies, fewer complications with a sustained low incidence of local recurrence, and better survival rates for rectal cancer patients,” commented Anna Martling from the Karolinska Institute. “The results can now be immediately put to clinical use to the considerable benefit of the patients.”

Sources: Erlandsson J, Holm T, Pettersson D, et al. Optimal fractionation of preoperative radiotherapy and timing to surgery for rectal cancer (Stockholm III): a multicentre, randomised, non-blinded, phase 3, non-inferiority trial. Lancet Oncol. doi: http://dx.doi.org/10.1016/S1470-2045(17)30086-4 (2017); www.eurekalert.org/pub_releases/2017-02/ki-nmr021017.php