Multidisciplinary treatment of patients with rectal cancer: Development during the past decades and plans for the future

Abstract

In rectal cancer treatment, both the local primary and the regional and systemic tumour cell deposits must be taken care of in order to improve survival. The three main treatments, surgery, radiotherapy, and chemotherapy, each with their own advantages and limitations, must then be combined to improve results. Several large randomized trials have shown that combinations of the modalities have markedly reduced the loco-regional recurrences, but have not yet had any major influence on overall survival. The best integration of the weakest modality, to date the drugs (conventional cytotoxics and biologicals), is not known. A new generation of trials exploring the best sequence of treatments is required. Furthermore, treatment of rectal cancer is administered to populations of individuals, based upon clinical factors and imaging, and can presently not be further individualized. There is an urgent need to develop response predictors.

Figure 1.

Subgrouping of localized rectal cancer assessed by MRI ¹⁾ and recommended primary treatment. ¹⁾The algorithm does not primarily address the risk of systemic disease, although this risk also increases with the presence of many of ‘the risk factors’, however, not necessarily parallel to the local failure rate (LFR). The algorithm is also ‘too simplified’ in that also other factors like size of the mesorectum, anterior or posterior location, extramural vascular invasion (EMVI+) are relevant. The recommendations are the ones in use at most centres in Sweden in 2011. ²⁾Calculated in the group of patients planned for surgery, i.e. irrespective of the surgical outcome. The figures are valid if the surgeon is an experienced rectal cancer surgeon and no pretreatment is given. ³⁾A local procedure is possible in a few patients (chiefly pT1, sm1 (+2), N0). This group is in the text referred to as ‘very favourable’. ⁴⁾CRT means chemoradiotherapy to 50.4 Gy in 1.8 Gy fractions with 5-fluorouracil (capecitabine); 5 × 5 Gy with delayed surgery is used in patients not fit for CRT.