Background: The risks of local recurrence and treatment-related morbidity need to be balanced after local excision of early rectal cancer. The aim of this meta-analysis was to determine oncological outcomes after local excision of pT1–2 rectal cancer followed by no additional treatment (NAT), completion total mesorectal excision (cTME) or adjuvant (chemo)radiotherapy (aCRT).Methods: A systematic search was conducted in PubMed, Embase and the Cochrane Library. The primary outcome was local recurrence. Statistical analysis included calculation of the weighted average of proportions.Results: Some 73 studies comprising 4674 patients were included in the analysis. Sixty-two evaluated NAT, 13 cTME and 28 aCRT. The local recurrence rate for NAT among low-risk pT1 tumours was 6·7 (95 per cent c.i. 4·8 to 9·3) per cent. There were no local recurrences of low-risk pT1 tumours after cTME or aCRT. The local recurrence rate for high-risk pT1 tumours was 13·6 (8·0 to 22·0) per cent for local excision only, 4·1 (1·7 to 9·4) per cent for cTME and 3·9 (2·0 to 7·5) per cent for aCRT. Local recurrence rates for pT2 tumours were 28·9 (22·3 to 36·4) per cent with NAT, 4 (1 to 13) per cent after cTME and 14·7 (11·2 to 19·0) per cent after aCRT.Conclusion: There is a substantial risk of local recurrence in patients who receive no additional treatment after local excision, especially those with high-risk pT1 and pT2 rectal cancer. The lowest recurrence risk is provided by cTME; aCRT has outcomes comparable to those of cTME for high-risk pT1 tumours, but shows a higher risk for pT2 tumours.

Background Tumour extension beyond the mesorectal plane (ymrT4) occurs in 5–10 per cent of patients with rectal cancer and 10 per cent of patients develop locally recurrent rectal cancer (LRRC) after primary surgery. There is global variation in healthcare delivery for these conditions. Methods An international benchmark trial of the management of ymrT4 tumours and LRRC was undertaken in France and Australia between 2015 and 2017. Heterogeneity in management and operative decision‐making were analysed by comparison of surgical resection rates, blinded intercountry reading of pelvic MRI, quality‐of‐life assessment and qualitative evaluations. Results Among 154 patients (97 in France and 57 in Australia), 31·8 per cent had ymrT4 disease and 68·2 per cent LRRC. The surgical resection rates were 88 and 79 per cent in France and Australia respectively (P = 0·112). The concordance in operative planning was low (κ = 0·314); the rate of pelvic exenteration was lower in France than Australia both in clinical practice (36 of 78 versus 34 of 40; P < 0·001) and in theoretical conditions (10 of 25 versus 50 of 57; P = 0·002). The R0 resection rate was lower in France than Australia for LRRC (25 of 49 versus 18 of 21; P = 0·007) but not for ymrT4 tumours (21 of 26 versus 15 of 15; P = 0·139). Morbidity rates were similar. Patients who underwent non‐exenterative procedures had higher scores on the mental functioning subscale at 12 months (P = 0·047), and a lower level of distress at 6 months (P = 0·049). Qualitative analysis highlighted five categories of psychosocial factors influencing treatment decisions: patient, strategy, specialist, organization and culture. Conclusion This international benchmark trial has highlighted the differences in worldwide treatment of locally advanced and LRRC. Standardized care should improve outcomes for these patients.