Molecular profiling of pediatric and young adult colorectal cancer reveals a distinct genomic landscapes and potential therapeutic avenues.

Colorectal cancer (CRC) is a global health concern, and the incidence of early onset (EO) CRC, has an upward trend. This study delves into the genomic landscape of EO-CRC, specifically focusing on pediatric (PED) and young adult (YA) patients, comparing them with adult (AD) CRC. In this retrospective monocentric investigation, we performed targeted next-generation sequencing to compare the mutational profile of 38 EO-CRCs patients (eight PED and 30 YA) to those of a 'control group' consisting of 56 AD-CRCs. Our findings reveal distinct molecular profiles in EO-CRC, notably in the WNT and PI3K-AKT pathways. In pediatrics, we observed a significantly higher frequency of RNF43 mutations, whereas APC mutations were more prevalent in adult cases. These observations suggest age-related differences in the activation of the WNT pathway. Pathway and copy number variation analysis reveal that AD-CRC and YA-CRC have more similarities than the pediatric patients. PED shows a peculiar profile with CDK6 amplification and the enrichment of lysine degradation pathway. These findings may open doors for personalized therapies, such as PI3K-AKT pathway inhibitors or CDK6 inhibitors for pediatric patients. Additionally, the distinct molecular signatures of EO-CRC underscore the need for age-specific treatment strategies and precision medicine. This study emphasizes the importance of comprehensive molecular investigations in EO-CRCs, which can potentially improve diagnostic accuracy, prognosis, and therapeutic decisions for these patients. Collaboration between the pediatric and adult oncology community is fundamental to improve oncological outcomes for this rare and challenging pediatric tumor.

Superior rectal artery preservation to reduce anastomotic leak rates in familial adenomatous polyposis patients treated with total colectomy and ileorectal anastomosis.

BACKGROUND: Total colectomy with ileorectal anastomosis (TC/IRA) is one of the prophylactic surgical options in patients with familial adenomatous polyposis (FAP). This study investigated the effectiveness of superior rectal artery (SRA) preservation during TC/IRA in reducing anastomotic leakage (AL). METHODS: This retrospective study was based on prospectively collected data (01/2000 - 12/2022) at the National Cancer Institute, Milan, Italy. FAP patients undergoing TC/IRA were enrolled. A 1:1  propensity score matching (PSM) was performed. Associations between SRA preservation and complications were investigated using univariate and multivariate analysis. RESULTS: The study population included 211 patients undergoing TC/IRA (Sex: 106 Male, 105 Female; Age: median 30 yrs, IQR: 20-48 yrs), 82 with SRA preservation (SRA group) and 129 without SRA preservation (controls). After PSM, 75 patients were considered for each group. SRA preservation was associated with fewer complications (OR 0.331, 95% CI 0.116; 0.942) in univariate logistic regression analysis. AL events were significantly fewer in the SRA group than in the control group (0 vs 12, p = 0.028). The SRA group had fewer overall surgical complication and pelvic sepsis rates (p = 0.020 and p = 0.028, respectively). Median operative time was significantly longer in the SRA group (340 min vs 240 min, p<0.001), and median hospital stay was significantly shorter (6 vs 7 days, p=0.017). Twenty-seven patients in the SRA group experienced intraoperative anastomotic bleeding, which was controlled endoscopically. Superimposable results were obtained analyzing the whole patient cohort. CONCLUSIONS: SRA preservation can be considered an advantage in this patient population, despite adding a further technical step during surgery and thereby prolonging the operative time. Intraoperative endoscopic checking of possible anastomotic bleeding sites is recommended.

Risk of desmoid tumours after open and laparoscopic colectomy in patients with familial adenomatous polyposis.

BACKGROUND: Desmoid tumour (DT) is a main cause of death after prophylactic colectomy in patients with familial adenomatous polyposis (FAP). The purpose of this study was to evaluate the impact of prophylactic laparoscopic colectomy on the risk of developing DT in patients with FAP. METHODS: The database of a single institution was reviewed. Patients with classical FAP with defined genotype who underwent either open or laparoscopic colectomy between 1947 and 2011 were included in the study. The impact of various demographic and clinical features on the risk of developing DT was assessed. RESULTS: A total of 672 patients underwent prophylactic colectomy: 602 by an open and 70 by a laparoscopic approach. With a median (range) follow-up of 132 (0-516) months in the open group and 60 (12-108) months in the laparoscopic group, 98 patients (16·3 per cent) developed DT after an open procedure compared with three (4 per cent) following laparoscopic surgery. The estimated cumulative risk of developing DT at 5 years after surgery was 13·0 per cent in the open group and 4 per cent in the laparoscopic group (P = 0·042). In multivariable analysis, female sex (hazard ratio (HR) 2·18, 95 per cent confidence interval 1·40 to 3·39), adenomatous polyposis coli mutation distal to codon 1400 (HR 3·85, 1·90 to 7·80), proctocolectomy (HR 1·67, 1·06 to 2·61), open colectomy (HR 6·84, 1·96 to 23·98) and year of surgery (HR 1·04, 1·01 to 1·07) were independent risk factors for the diagnosis of DT after prophylactic surgery. CONCLUSION: Laparoscopic surgery decreased the risk of DT after prophylactic colectomy in patients with FAP.

Quantitative and qualitative characterization of plasma DNA identifies primary and recurrent colorectal cancer.

Because plasma DNA may be a useful tool for cancer detection, we screened primary tumors and related multiple plasma samples at the time of surgery and during the follow-up period for plasma DNA level as well as for K-Ras mutations and p16INK4a promoter hypermethylation in colorectal cancer patients. At the time of surgery, DNA levels were higher in tumor patients than in healthy donors, and K-Ras and p16INK4a alterations were detected in 7 and 11 cancers respectively, and in all related plasma samples. During the follow-up, plasma DNA levels decrease progressively but rapidly increased when a relapse occurred, whereas K-Ras and p16INK4a alterations were detected only in relapsed patients. Therefore, combined quantitative and qualitative analyses of plasma DNA confirm the presence of colorectal cancer, define disease-free status and indicate the presence of relapse.