Accuracy of deep neural learning models in the imaging prediction of pathological complete response after neoadjuvant chemoradiotherapy for locally advanced rectal cancer: a systematic review.

PURPOSE: Up to 15-27% of patients achieve pathologic complete response (pCR) following neoadjuvant chemoradiotherapy (CRT) for locally advanced rectal cancer (LARC). Deep neural learning (DL) algorithms have been suggested to be a useful adjunct to allow accurate prediction of pCR and to identify patients who could potentially avoid surgery. This systematic review aims to interrogate the accuracy of DL algorithms at predicting pCR. METHODS: Embase (PubMed, MEDLINE) databases and Google Scholar were searched to identify eligible English-language studies, with the search concluding in July 2022. Studies reporting on the accuracy of DL models in predicting pCR were selected for review and information pertaining to study characteristics and diagnostic measures was extracted from relevant studies. Risk of bias was evaluated using the Newcastle-Ottawa scale (NOS). RESULTS: Our search yielded 85 potential publications. Nineteen full texts were reviewed, and a total of 12 articles were included in this systematic review. There were six retrospective and six prospective cohort studies. The most common DL algorithm used was the Convolutional Neural Network (CNN). Performance comparison was carried out via single modality comparison. The median performance for each best-performing algorithm was an AUC of 0.845 (range 0.71-0.99) and Accuracy of 0.85 (0.83-0.98). CONCLUSIONS: There is a promising role for DL models in the prediction of pCR following neoadjuvant-CRT for LARC. Further studies are needed to provide a standardised comparison in order to allow for large-scale clinical application. PROPERO REGISTRATION: PROSPERO 2021 CRD42021269904 Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021269904 .

The utility of ctDNA in colorectal cancer with peritoneal metastases.

BACKGROUND: The development of peritoneal metastases (PM) in patients with colorectal cancer (CRC) connotates a poor prognosis. Circulating tumour (ctDNA) is a promising tumour biomarker in the management CRC. This systematic review aimed to summarize the role of ctDNA in patients with CRC and PM. METHODS: Following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, a systematic review of the literature until June 2022 was performed. Studies reporting on the utility of ctDNA in colorectal PM were included. A total of eight eligible studies were identified including a total of 167 patients. RESULTS: The findings from this review suggest an evolving role for ctDNA in CRC with PM. ctDNA can be isolated from both plasma and peritoneal fluid, with peritoneal fluid preferred as the liquid biopsy of choice with higher mutation detection rates. Concordance rates between tissue and plasma/peritoneal ctDNA mutation detection can vary, but is generally high. ctDNA has a potential role in monitoring anti-EGFR treatment response and resistance, as well as in predicting future prognosis and recurrence. The detection of ctDNA in plasma of patients with isolated PM is also possibly suggestive of occult systemic disease, and patients exhibiting such ctDNA positivity may benefit from systemic treatment. Limitations to ctDNA mutation detection may include the size of peritoneal lesions, as well as the fact that PM poorly shed ctDNA. CONCLUSION: While these findings are promising, further large-scale studies are needed to better evaluate the utility of ctDNA in this subset of patients.

Massive gastric distension due to bulimia nervosa: a hotpot emergency.

Acute massive gastric distension is a rare but potentially life-threatening surgical complication of bulimia nervosa. This results from repeated binge eating and is likely compounded by increased gastric compliance and delayed gastric emptying. We describe a case of acute massive gastric distension in a 26-year-old female with undiagnosed bulimia nervosa who underwent a laparotomy and anterior gastrotomy after failed conservative measures for gastric decompression. It highlights the importance of early recognition of a potentially life-threatening condition and that a multi-disciplinary approach is necessary to prevent the recurrence and morbidity associated with it.

Anastomotic Leak in Colorectal Surgery: Predictive Factors and Survival.

<br><b>Introduction:</b> Anastomotic leak (AL) is a serious complication following colorectal surgery.</br> <br><b>Aim:</b> The aim of this study was to identify factors associated with the development of AL and to analyze its impact on survival.</br> <br><b>Materials and methods:</b> All consecutive adult colorectal cancer resections performed between 2007 and 2020 with curative intent and anastomosis formation were included from a prospectively maintained database. The primary outcome measure was the rate of AL. The secondary outcome measure was 5-year overall survival (OS).</br> <br><b>Results:</b> There were 6837 eligible patients. The rate of AL was 2.2% and 4.0% in patients with colon and rectal cancer, respectively. AL was a significant independent predictor of reduced 5-year OS in patients who underwent curative surgery for rectal cancer (odds ratio 2.293, p = 0.009). Emergency surgery (p = 0.015), surgery at a public hospital (p = 0.002), and an open surgical approach (p = 0.021) were all associated with a significantly higher risk of AL in patients with colon cancer, with higher rates of AL noted in left colectomies as compared to right hemicolectomies (4.4% <i>vs.</i> 1.3%, p < 0.001). In rectal cancer patients, AL was associated with neoadjuvant chemoradiotherapy (p = 0.038) and male gender (p = 0.002). The anastomosis formation technique (hand-sewn <i>vs.</i> stapled) did not impact the rate of AL (p = 0.116 and p = 0.198 with colon and rectal cancer, respectively).</br> <br><b>Discussion:</b> Clinicians should be cognizant of the predictive factors for AL and should consider early intervention for at-risk patients.</br>.

Predictive Factors for Anastomotic Leak in Colorectal Surgery: A Bi-National Database Study.

IntroductionAnastomotic leak (AL) is a serious complication following colorectal surgery. This study aimed to identify factors associated with the development of AL and analyze its impact on survival.Materials and MethodsAll consecutive adult colorectal cancer resections with curative intent and anastomosis formation were included from a prospectively maintained bi-national database between 2007 and 2020. The primary outcome measure was the rate of AL. The secondary outcome measure was 5-year overall survival (OS).ResultsThere were 7566 eligible patients. The rate of AL was 2.3% and 4.4% in patients with colon and rectal cancer respectively. AL was a significant independent predictor of reduced 5-year OS in patients who underwent curative surgery for rectal cancer (Odds ratio 1.999, p = 0.017). Emergency surgery (p = 0.013), surgery at a public hospital (p < 0.01), and an open surgical approach (p = 0.002) were all significantly associated with a higher risk of AL in patients with colon cancer, with higher rates of AL noted in left colectomies as compared to right hemicolectomies (6.8% vs 1.6%, p < 0.05). In rectal cancer patients, ultra-low anterior resections had the highest risk of AL (4.6%), and associations were found with neoadjuvant chemotherapy (p = 0.011), surgery in a public hospital (p = 0.019), and an open approach (p = 0.035). Anastomosis formation technique (hand-sewn vs stapled) did not impact on rate of AL.DiscussionClinicians should be cognizant of the predictive factors for AL and consider early intervention for patients at risk of this.

Survival benefit of neoadjuvant chemotherapy and surgery versus surgery first for resectable colorectal liver metastases: a cohort study.

BACKGROUND: There is continued debate about the survival benefit of neoadjuvant chemotherapy (neoCT) in patients with resectable colorectal liver metastases (CRLM). METHODS: In this retrospective cohort study, we included 201 patients with metastatic colorectal cancer who underwent their first CRLM resection and achieved resection of all sites of disease. We compared the overall survival (OS) and progression-free survival (PFS) between patients who received neoCT prior to CRLM resection with those who underwent CRLM upfront. A multivariable Cox proportional hazard regression analysis was performed to adjust for potential confounders. RESULTS: A total of 101 of 201 (51.2%) patients received chemotherapy prior to CRLM resection and 100 of 201 had surgery upfront. Multivariable Cox proportional hazard regression showed no statistically significant difference in the hazard of death for those given neoCT prior to resection of CRLM compared with surgery first for both OS and PFS (OS: hazard ratio 1.74, 95% confidence interval 0.85-3.55, P = 0.127, PFS: hazard ratio 1.42, 95% confidence interval 0.93-2.19, P = 0.107). CONCLUSION: In our series of patients with metastatic colorectal cancer who achieved surgical resection of all sites of disease, neoCT prior to CRLM resection was not associated with any survival benefit.