Somatic NGS Analysis of DNA Damage Response (DDR) Genes ATM, MRE11A, RAD50, NBN, and ATR in Locally Advanced Rectal Cancer Treated with Neoadjuvant Chemo-Radiotherapy.

BACKGROUND: Neoadjuvant chemo-radiotherapy (nCRT) represents the standard of care for locally advanced rectal cancer (LARC); however, there exists no biomarker that can predict the cancer's response to treatment as less than 20% of patients experience pathological complete response (pCR). Ionizing radiations induce double strand breaks (DSBs) and trigger a DNA damage response (DDR) involving ATM, ATR, and the MRN complex (MRE11, Rad50, and NBS1). In this study, we performed an extensive mutational analysis of the genes involved in the DDR pathway in LARC patients who have undergone nCRT. METHODS: 13 LARC patients with pCR and 11 LARC patients with partial response (pPR) were investigated using a NGS dedicated panel, designed for formalin-fixed paraffin-embedded (FFPE) samples, containing ATR, ATM, and MRE11-RAD50-NBN genes. The identified variants were classified according to guidelines' recommendations. RESULTS: Eight non-benign variants, six of which were observed in 3 (23%) out of 13 pCR patients, were identified. In particular, a pCR patient carried out a pathogenetic frameshift mutation in exon 21 of the RAD50 gene. The two remaining non-benign missense variants were found in 2 (18%) out of 11 patients in the pPR group. CONCLUSIONS: Our data show that the genes involved in the Homologous Recombination (HR) pathway are rarely mutated in LARC; however, given the identification of a missense mutation in RAD 50 in one case of pCR, it could be worth exploring its potential role as a biomarker in larger series.

Laparoscopic versus open rectal resection: a 1:2 propensity score-matched analysis of oncological adequateness, short- and long-term outcomes.

BACKGROUND: Laparoscopic resections for rectal cancer are routinely performed in high-volume centres. Despite short-term advantages have been demonstrated, the oncological outcomes are still debated. The aim of this study was to compare the oncological adequateness of the surgical specimen and the long-term outcomes between open (ORR) and laparoscopic (LRR) rectal resections. METHODS: Patients undergoing laparoscopic or open rectal resections from January 1, 2013, to December 31, 2019, were enrolled. A 1:2 propensity score matching was performed according to age, sex, BMI, ASA score, comorbidities, distance from the anal verge, and clinical T and N stage. RESULTS: Ninety-eight ORR were matched to 50 LRR. No differences were observed in terms of operative time (224.9 min. vs. 230.7; p = 0.567) and postoperative morbidity (18.6% vs. 20.8%; p = 0.744). LRR group had a significantly earlier soft oral intake (p < 0.001), first bowel movement (p < 0.001), and shorter hospital stay (p < 0.001). Oncological adequateness was achieved in 85 (86.7%) open and 44 (88.0%) laparoscopic resections (p = 0.772). Clearance of the distal (99.0% vs. 100%; p = 0.474) and radial margins (91.8 vs. 90.0%, p = 0.709), and mesorectal integrity (94.9% vs. 98.0%, p = 0.365) were comparable between groups. No differences in local recurrence (6.1% vs.4.0%, p = 0.589), 3-year overall survival (82.9% vs. 91.4%, p = 0.276), and disease-free survival (73.1% vs. 74.3%, p = 0.817) were observed. CONCLUSIONS: LRR is associated with good postoperative results, safe oncological adequateness of the surgical specimen, and comparable survivals to open surgery.

Clinico-pathological Features of Colon Cancer Patients Undergoing Emergency Surgery: A Comparison Between Elderly and Non-elderly Patients.

BACKGROUND: Colorectal cancer (CRC) is one of the most common cancers in patients older than 65 years. Emergency presentation represents about 30% of cases, with increased morbidity and mortality rates. The aim of this study is to compare the perioperative outcome between elderly and non-elderly patients undergoing emergency surgery. METHOD: We retrospectively analysed CRC patients that underwent emergency surgery at the Departments of Surgery of the Sapienza University Sant'Andrea Hospital in Rome, and at San Donato Hospital in Arezzo, between June 2012 and June 2017. Patients were divided into two groups: non-elderly (< 65 years) and elderly (≥ 65 years). Variables analysed were sex, onset symptoms, associated disease, ASA score, tumor site and TNM stage, surgical procedures and approach, and morbidity and mortality. RESULTS: Of a total of 123 patients, 29 patients were non-elderly and 94 patients were elderly. No significant differences were observed in sex, onset symptoms and tumor site between the two groups. Comorbidities were significantly higher in elderly patients (73.4% vs 41.4%, p<0.001). No significant differences were observed between the two groups in surgical approach and the rate of one-stage procedures. Elderly patients were more frequently treated by Hartmann's procedure compared to non-elderly patients (20.2% vs 6.9%). Left colorectal resection with protective ileostomy was most frequent in the non-elderly group (27.6% vs 11.7%). No significant differences were found in the pT and pN categories of the TNM system between the two groups. However, a higher number of T3 in non-elderly patients was observed. A consistent number of non-oncologically adequate resections were observed in the elderly (21.3% vs 3.5%; p<0.03). The morbidity rate was significantly higher in the elderly group (31.9 % vs 3.4%, p<0.001). No significant difference was found in the mortality rate between the two groups, being 13.8% in the elderly and 6.9% in the non-elderly. CONCLUSIONS: Emergency colorectal surgery for cancer still presents significant morbidity and mortality rates, especially in elderly patients. More aggressive tumors and advanced stages were more frequent in the non-elderly group and as a matter it should be taken into account when treating such patients in the emergency setting in order to perform a radical procedure as much as possible.

Curative and Prophylactic Surgery of Young-onset Colorectal Cancer in Inherited Syndromes: A 15-Year Monocentric Retrospective Experience.

BACKGROUND/AIM: Although genoproteomic and clinicopathological knowledge on Lynch syndrome (LS) and familial adenomatous polyposis (FAP) has notably increased during the past two decades and even though surgery represents the mainstay of treatment for both conditions, as of 2019, the surgical choice in terms of timing and procedure still appears controversial in the absence of definitive guidelines. MATERIALS AND METHODS: Data were retrospectively analyzed of patients with colorectal cancer (CRC) surgically treated at our Institution between 1st January 2003 and 31st December 2018. Particular attention was given to patients with LS and FAP ≤45 years of age (young-onset CRC); for this category of patients, the surgical procedures performed were compared in terms of benefits and disadvantages. RESULTS: A total of 1,878 primary CRCs were submitted to major surgery; young-onset malignancies accounted for 3.8% of all CRCs. Thirteen young-onset inherited CRCs were surgically removed from 11 patients with LS and two with FAP. Segmental colectomy and restorative proctocolectomy were the procedures most frequently performed in young patients with LS and FAP, respectively. CONCLUSION: In the light of our retrospective results, we highlight the need for randomized controlled trials comparing the surgical options for LS- and FAP-related CRC developing in young patients. Defining the advantages and risks of each surgical option is of the utmost importance in order to improve prognosis of such patients and establish unanimous recommendations.

Study of histopathologic parameters to define the prognosis of stage II colon cancer.

PURPOSE: Stage II colon cancer (CC) represents a challenging scenario for the choice of adjuvant chemotherapy; here, histologic factors need to be weighed up to establish the risk of recurrence. Tumor budding (TB) has recently been indicated as a confident predictor of clinical outcome in CC. Likewise, the presence of poorly differentiated clusters (PDCs) in a tumor has been pointed out as a leading criterion of a tumor grading system. Our aim was to evaluate in patients with stage II CC the relationship between these features and clinical outcome. PATIENTS AND METHODS: The study included 174 cases of stage II CC; histopathologic parameters such as TB, PDCs, microsatellite instability (MSI), and CDX2 expression were analyzed. RESULTS: There were 107 (70.9%), 32 (21.2%), and 12 (7.9%) TB scored 1, 2, and 3 respectively; 113 (72.9%), 30 (19.4%), and 12 (7.7%) tumors showed grade 1, 2, and 3 PDCs respectively. A high-MSI was detected in 32 cases (18.4%) while CDX2 was negative in 20 (11.5%) tumor samples. In the whole study population, only the TB was found to be associated with disease-specific survival (P = 0.01). No parameter apart from age (P = 0.04) was a significant prognostic factor for overall survival (P < 0.05). Other commonly reported variables, including tumor size, degree of tumor differentiation, lymphovascular invasion, number of lymph nodes harvested ≥ 12, MSI, and PDCs, were not shown to have significant results. CONCLUSIONS: Although confirmatory studies are awaited, our work supports the role of the TB in defining risk groups of the stage II CC.

Reconstruction After Distal Gastrectomy for Gastric Cancer: Billroth 2 or Roux-En-Y Procedure?

BACKGROUND/AIM: Distal gastrectomy (DG) represents the only curative treatment for most mid-lower gastric cancers (GCs). As of 2017, however, no reconstructive modality to conduct after DG has gained unanimous consensus. Additionally, most authors have investigated Billroth 1 and Roux-en-Y (RY) rather than Billroth 2 (B2) reconstruction. We analyzed B2 and RY gastrojejunostomy to identify the preferable technique and augment the available information on B2 restoration. PATIENTS AND METHODS: We retrospectively selected 132 GC patients who were consecutively submitted to DG at our institution between April 2005 and February 2016. B2 and RY anastomosis were accomplished as methods of reconstruction (respectively 36 and 96 cases). We compared these techniques in terms of clinicopathological, surgical, postoperative and oncologic outcomes. RESULTS: Compared to RY gastrojejunostomy, B2 reconstruction was significantly associated with a greater mean number of harvested lymph nodes (26.03 vs. 21.65, p=0.045) but also with a longer hospital stay (22.8 vs. 15.7 days) (p=0.022) and higher readmission rate (28.57% vs. 3.1%, p<0.0001). On multivariate analysis, reconstruction method was the most significant independent prognostic factor for hospital readmission. CONCLUSION: In light of our results, we propose that B2 gastrojejunostomy deserves more study in order to better identify the best post-DG anastomosis.

Emergency surgery for colorectal cancer does not affect nodal harvest comparing elective procedures: a propensity score-matched analysis.

PURPOSE: About 30% of colorectal cancers (CRCs) present with acute symptoms. The adequacy of oncologic resections is a matter of concern since few authors reported that emergency surgery in these patients results in a lower lymph node harvest (LNH). In addition, emergency resections have been reported with a longer hospital stay and higher morbidity rate. We thus conducted a propensity score-matched analysis with the aim of investigating LNH in emergency specimens comparing with elective ones. Secondary aim was the comparison of morbidity and hospital stay. METHODS: Eighty-seven consecutive R0 emergency surgical procedures were matched with elective CRCs using the propensity score method and the following covariates: age, sex, stage, and localization. Groups were compared using univariate and multivariate analyses. Outcome measures were LNH, nodal ratio, Clavien's morbidity grades, and hospital stay. RESULTS: Emergency patients presented more metastatic nodes compared with elective ones (p 0.017); however, both presented a comparable mean LNH. Multivariate analysis documented that a T stage ≥3 was the only variable correlated with a nodal positivity (OR 6.3). On univariate analysis, emergency CRCs had a longer mean hospital stay compared with elective resections (p 0.006) and a higher rate of Clavien ≥4 events (p 0.0173). Finally, emergency resection and an age >66 years were variables independently correlated with a mean hospital stay >10 days (OR, respectively, 3.7 and 3.5). CONCLUSIONS: Emergency CRC resections were equivalent to the elective procedures with respect to LNH. However, emergency surgery correlated with a longer mean hospital stay. Graphical abstract Emergency and Elective resections for CRC provide similar LNH.

Left-sided early onset colorectal carcinomas: A sporadic neoplasm with aggressive behavior.

BACKGROUND: Early onset (≤50y) colorectal carcinomas (EO-CRCs) are increasing in incidence according to epidemiological data. We investigated clinical-pathological, molecular features and outcomes of 62 left sided EO-CRCs (EOLS-CRCs) and compared them to a group of late onset (≥65) LS-CRCs (LOLS-CRCs). MATERIALS AND METHODS: Samples were evaluated for pathological features and microsatellite instability (MSI). Overall survival (OS), disease free survival (DFS) and disease specific survival were evaluated in both groups. RESULTS: Five out 62 (8%) EOLS-CRCs showed MSI phenotype. Interestingly these cases were aged 26-39y. Most EOLS-CRCs present at advanced stage and this was statistically significant when compared to LOLS-CRCs. OS was better in EOLS-CRCs whilst DFS showed a worst profile in EOLS-CRCs either in low and high stages even though young patients were treated more often with adjuvant chemotherapy compared to older ones at the same disease stage. CONCLUSIONS: Most EOLS-CRCs are sporadic non Lynch, microsatellite stable (MSS) CRCs. Our data show that when compared with LOLS-CRCs the early group represents an aggressive disease with worst outcome underlining a possible different carcinogenic pathway.

Value of diffusion-weighted MRI and apparent diffusion coefficient measurements for predicting the response of locally advanced rectal cancer to neoadjuvant chemoradiotherapy.

PURPOSE: The aim of our study was to assess the performance value of magnetic resonance imaging (MRI) in the restaging of locally advanced rectal cancer after neoadjuvant chemoradiotherapy (CRT) and in the identification of good vs. poor responders to neoadjuvant therapy. MATERIALS AND METHODS: A total of 34 patients with locally advanced rectal cancer underwent MRI prior to and after CRT. T stage and tumor regression grade (TRG) on post-CRT MRI was compared with the pathological staging ypT and TRG. Tumor volume and the apparent diffusion coefficient (ADC) were measured using diffusion-weighted imaging (DWI) before and after neoadjuvant CRT; the percentage of tumor volume reduction and the change of ADC (ΔADC) was also calculated. ADC parameters and the percentage of tumor volume reduction were correlated to histopathological results. The diagnostic performance of ADC and volume reduction to assess tumor response was evaluated by calculating the area under the ROC curve and the optimal cut-off values. RESULTS: A significant correlation between the T stage and the TRG defined in DW-MRI after CRT and the ypT and the TRG observed on the surgical specimens was found (p = 0.001; p < 0.001). The mean post-CRT ADC and ΔADC in responder patients was significantly higher compared to non-responder ones (p = 0.001; p = 0.01). Furthermore, the mean post-CRT ADC values were significantly higher in tumors with T-downstage (p = 0.01). CONCLUSION: DW-MRI may have a significant role in the restaging and in the evaluation of post-CRT response of locally advanced rectal cancer. Quantitative analysis of DWI through ADC map may result in a promising noninvasive tool to evaluate the response to therapy.

Right Colectomy for Cancer: A Matched Comparison of Three Different Surgical Approaches.

PURPOSE: The standard approach to right colon cancer resection is still a matter of debate and includes laparoscopy, open midline incision, or open transverse incision. We aimed this study to compare the short- and long-term results of laparoscopic right-colectomy with those provided by the open approaches. METHODS: Of the 176 patients who underwent right-colectomy at our Department for nonmetastatic colon cancer, 40 patients treated by laparoscopy, 40 treated by transverse incisions, and 40 treated by midline incisions were selected and matched using the propensity score method. Short-term results included: operating time, morbidity rate, number of lymph-nodes harvested (LNH), patients' recovery features, and costs. Long-term results included: disease-specific survivals and the rate of incisional hernias. The sub-groups were compared using t-test and Chi-square tests, whereas the Kaplan-Meier method was used to assess survivals. RESULTS: Laparoscopies were the longer procedures, providing similar morbidity rates and LNH in comparison with the open approaches. Laparoscopy provided a faster return to oral intake and a shorter use of analgesics comparing with the midline approach; however, it showed only a minor consumption of analgesics in comparison with transverse laparotomy. There were no differences in the hospital stay and the long-term results were comparable between sub-groups. Costs analysis documented minor but not significant surgical expenses for the transverse approach. CONCLUSIONS: Laparoscopy was documented safe, with similar morbidity rates and long-term results comparing with open surgery. Laparoscopy provided better functional short-term results comparing with the midline approach, but only small differences with respect to the transverse incision approach.

Laparoscopic versus robotic-assisted colectomy and rectal resection: a systematic review and meta-analysis.

PURPOSE: Lately, the main technical innovations in the field of colorectal surgery have been the introduction of laparoscopic and robotic techniques; the aim of this study is to investigate the results and the advantages of these two surgical approaches. METHODS: Twenty-two studies including 1652 laparoscopic and 1120 robotic-assisted resections were analyzed and categorized into right, left, and pelvic resections of the middle/low rectum, aiming to the following outcomes: operating time, blood loss, bowel function recovery, return to oral intake, morbidity, hospital stay, and costs. RESULTS: The vast majority of the studies were non-randomized investigations (19/22 studies) enrolling small cohorts of patients (median 55.0 laparoscopic and 34.5 robotic-assisted group) with a mean age of 62.2-61.0 years. Funnel plot analysis documented heterogeneity in studies which combined cancers and benign diseases. Our meta-analysis demonstrated a significant difference in favor of laparoscopic procedures regarding costs and operating time (standardized mean difference (SMD) 0.686 and 0.493) and in favor of robotic surgery concerning morbidity rate (odds ratio (OR) 0.763), although no benefits were documented when analyzing exclusively randomized trials. When we differentiated approaches by side of resections, a significant difference was found in favor of the laparoscopic group when analyzing operating time in left-sided and pelvic procedures (SMD 0.609 and 0.529) and blood loss in pelvic resections (SMD 0.339). CONCLUSION: Laparoscopic techniques were documented as the shorter procedures, which provided lower blood loss in pelvic resections, while morbidity rate was more favorable in robotic surgery. However, these results could not be confirmed when we focused the analysis on randomized trials only.

Left-sided early-onset vs late-onset colorectal carcinoma: histologic, clinical, and molecular differences.

OBJECTIVES: Carcinomas of the left colon represent a neoplasm of older patients (late onset), but epidemiologic evidence has been showing an increasing incidence in patients 50 years or younger (early onset). In this study, we investigate pathologic and molecular features of early- and late-onset carcinoma of the left colon. METHODS: We selected 22 patients 50 years or younger and 21 patients 70 years or older with left-sided colorectal carcinoma (CRC). All samples were evaluated for pathologic features, microsatellite instability, and KRAS and BRAF mutations. Moreover, both groups were analyzed to identify CpG island methylator phenotype features and assessed with restriction landmark genome scanning (RLGS) to unveil differential DNA methylation patterns. RESULTS: Early-onset patients had advanced pathologic stages compared with late-onset patients (P = .0482). All cases showed a microsatellite stable profile and BRAF wild-type sequence. Early-onset patients (43%) more frequently had mutations at KRAS codon 12 compared with late-onset patients (14%) (P =.0413). RLGS showed that patients younger than 50 years who had CRC had a significantly lower percentage of methylated loci than did patients 70 years or older (P = .04124), and differential methylation of several genomic loci was observed in the two groups. CONCLUSIONS: Our results suggest that left-sided CRCs may present differential patterns of aberrant DNA methylation when they are separated by age.

Human papillomavirus does not have a causal role in colorectal carcinogenesis.

AIM: To investigate the presence of human papillomavirus (HPV) DNA along with the integration, the quantification and the expression of the HPV16 in colorectal cancers. METHODS: A prospective series of colorectal tumors were genotyped for HPV DNA. The clinical and pathological variables of the HPV-positive tumors were compared to those of HPV-negative samples. The integration status of HPV16 was evaluated by calculating E2/E6 ng ratios. HPV16-positive tumors were also evaluated for (1) E2, E4, E5, E6 and E7 viral gene ng quantification; (2) relative quantification compared to W12 cells; and (3) viral E2, E4, E5, E6 and E7 mRNA transcripts by real-time polymerase chain reaction. RESULTS: HPV infection was detected in 16.9% of all tumors examined, and HPV16 was the most frequent type detected (63.6% of positive tissues). Notably, the clinical and pathological features of HPV-positive colorectal cancers were not significantly different than those of HPV-negative cancers (χ (2) and t-test for all clinical and pathological features of HPV-positive vs HPV-negative colorectal cancers: p ns). HPV16 DNA was present exclusively in episomal form, and the HPV16 E2, E4, E5, E6 and E7 genes were detected in trace nanogram quantities. Furthermore, the HPV16 genes ranged from 10(-3) to 10(-9) compared to W12 cells at an episomal stage. Although the extractions were validated by housekeeping gene expression, all the HPV16 positive tissues were transcriptionally inactive for the E2, E4, E5, E6 and E7 mRNAs. CONCLUSION: Based on our results, HPV is unlikely involved in colorectal carcinogenesis.