Inflammatory bowel disease (IBD) [i.e., Crohn’s disease (CD) and ulcerative colitis (UC)] has been considered a relative contraindication for radiation therapy (RT) to the abdomen or pelvis, potentially preventing patients with a diagnosis of IBD from receiving definitive therapy for their malignancy.

Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) conventions, a PubMed/MEDLINE literature search was conducted using the keywords RT, brachytherapy, inflammatory bowel disease, Crohn’s disease, ulcerative colitis and toxicity.

A total of 1,206 publications were screened with an addition of 8 studies identified through hand searching. Nineteen studies met the inclusion criteria for quantitative analysis. The total population across all studies was 497 patients, 50·5% having UC, 37% having CD and an additional 12·5% having unspecified IBD. Primary gastrointestinal malignancy (55%) followed by prostate cancer (40%) composed the bulk of the population. Acute and late grade 3 or greater gastrointestinal specific toxicity ranged from 0–23% to 0–13% respectively for those patients with IBD treated with RT to the abdomen or pelvis. In the literature reviewed, RT does not appear to increase fistula or stricture formation or IBD flares; however, one study did note RT to be a statistically significant risk factor for subsequent IBD flare on multivariate analysis.

A review of reported acute and late toxicities suggests that patients with IBD should still be considered for definitive radiotherapy. Patient characteristics including IBD distribution relative to the irradiated field, inflammatory activity at the time of radiation, overall disease severity and disease phenotype in the case of CD (fistulising versus stricturing versus inflammatory only) should be considered on an individual basis when evaluating potential patients. When possible, advanced techniques with strict organ at risk dose constraints should be employed to limit toxicity in this patient population.

Although hypofractionated radiotherapy has been standardised in early breast cancer, even in post-mastectomy no such consensus has been developed for locally advanced breast cancer (LABC), probably due to complex planning and field matching. This study is directed towards dosimetric evaluation and comparison of toxicity, response and disease-free survival (DFS) comparison between hypofractionation and conventional radiotherapy in post-mastectomy LABC.

In total, 222 female breast cancer patients were randomly assigned to be treated with either hypofractionated radiotherapy (n = 120) delivering 40 Gy in 15 fractions over 3 weeks or conventional radiotherapy (n = 102) with 50 Gy in 25 fractions over 5 weeks after modified radical mastectomy (MRM) along with neoadjuvant and/or adjuvant chemotherapy. All patients were planned with treatment planning software and assessed regularly during and after treatment.

Median follow-up period was 178 weeks in conventional arm (CRA) and 182 weeks in hypofractionation arm (HFA). There exists a dosimetric difference between the two arms of treatment, in spite of similar dose coverage [planning treatment volume (PTV) D90 92·04% in CRA versus 92·5% in HFA; p = 0·49], average dose in HFA is less than that of CRA (p < 0·001); so is the maximum clinical target volume (CTV) dose (p < 0·001). Similarly, average lung dose in HFA arm is significantly lower than CRA (9·9 versus 10·84; p = 0·06), but the V20Gy of lung and V30Gy of heart had no difference. The toxicity of radiation was comparable with similar mean time to produce toxicity [CRA: 7 W, HFA: 10 W; hazard ratio 0·64, 95% confidence interval (CI) = 0·28–1·45]. Three-year recurrence event was alike in two arms (CRA: 4·9%, HFA: 5·8%; p = 0·76). Mean DFS in CRA is 230 weeks and that of HFA is 235 weeks with hazard ratio 1·01 (95% CI = 0·32–3·19; p = 0·987).

Though biologically effective dose (BED) in hypofractionation is lesser than that of conventional fractionation, there are indistinguishable toxicity, locoregional recurrence, distant failure rate and DFS between the two modalities.