Background Neoadjuvant chemotherapy for breast cancer has the potential to achieve a pathological complete response in up to 40 per cent of patients, converting disease that was initially node‐positive to node‐negative. This has raised the question of whether sentinel lymph node biopsy could be an alternative to axillary lymph node dissection in these patients. The aim was to undertake a systematic review and meta‐analysis of the accuracy and reliability of sentinel lymph node biopsy after neoadjuvant chemotherapy in patients with initial biopsy‐proven node‐positive breast cancer. Methods A literature search was conducted using PubMed, Ovid MEDLINE, Embase and Web of Science databases up to 30 April 2017. Inclusion criteria for studies were pathological confirmation of initial node‐positive disease, and sentinel lymph node biopsy performed after neoadjuvant chemotherapy followed by axillary lymph node dissection. Results A total of 13 studies met the inclusion criteria and were included in the analysis (1921 patients in total). The pooled estimate of identification rate was 90 (95 per cent c.i. 87 to 93) per cent and the false‐negative rate was 14 (11 to 17) per cent. In subgroup analysis, the false‐negative rate with use of dual mapping was 11 (6 to 15) per cent, compared with 19 (11 to 27) per cent with single mapping. The false‐negative rate was 20 (13 to 27) per cent when one node was removed, 12 (5 to 19) per cent with two nodes removed and 4 (0 to 9) per cent with removal of three or more nodes. Conclusion Sentinel lymph node biopsy after neoadjuvant chemotherapy in patients with biopsy‐proven node‐positive breast cancer is accurate and reliable, but requires careful patient selection and optimal surgical techniques.

Among the majority of respondents to this survey, MBP is used routinely for rectal operations. For colonic surgery, laparoscopic surgeons have a significantly lower use of MBP. Use of oral antibiotic bowel preparation remains uncommon.

The effect of SNM in this animal model is governed principally by frequency, with an optimum of 2 Hz. If animal data can be translated to humans, optimization of SNM frequency may offer a clinically relevant improvement in the efficacy of SNM. Surgical relevance Sacral neuromodulation (SNM) for faecal incontinence currently employs stimulation parameters that have been derived empirically and may not be optimal. This study used an animal model of SNM and focused on its acute effect on anal canal cortical evoked potentials (EPs). It was found that SNM potentiated EPs, with a clear optimum at a frequency of 2 Hz. If this finding is applicable to the mechanism of action of human SNM, this suggests that there may be a clinically relevant improvement by reducing stimulus frequency from its typical value of 14 Hz to 2 Hz.

The colonic mucus gel layer (MGL) is a critical component of the innate immune system acting as a physical barrier to microbes, luminal insults, and toxins. Mucins are the major component of the MGL. Selected microbes have the potential to interact with, bind to, and metabolize mucins. The tolerance of the host to the presence of these microbes is critical to maintaining MGL homeostasis. In disease states such as ulcerative colitis (UC), both the mucosa associated microbes and the constituent MGL mucins have been shown to be altered. Evidence is accumulating that implicates the potential for mucin degrading bacteria to negatively impact the MGL and its stasis. These effects appear more pronounced in UC.   This review is focused on the host-microbiome interactions within the setting of the MGL. Special focus is given to the mucolytic potential of microbes and their interactions in the setting of the colitic colon.