This is a protocol for a Cochrane Review (prognosis). The objectives are as follows:

Primary objectives

To identify and estimate the prognostic value of molecular biomarkers as predictors of pathological complete response to neoadjuvant chemoradiotherapy in people with locally advanced rectal cancer.

Table 1 summarises the review question in population, index prognostic factor, comparator prognostic factor(s), outcome, timing, and setting (PICOTS) format.

Secondary objectives

To explore the following biomarker measurement, treatment, and study design factors as possible sources of heterogeneity in the association between the prognostic factor and pathological response: type of assay/measurement method, biomarker positivity criteria or cut-off point, chemotherapy regimen, and radiotherapy regimen.