Prevalence of nodal involvement in rectal cancer after chemoradiotherapy.

BACKGROUND: The purpose of this study was to investigate the prevalence of ypN+ status according to ypT category in patients with locally advanced rectal cancer treated with chemoradiotherapy and total mesorectal excision, and to assess the impact of ypN+ on disease recurrence and survival by pooled analysis of individual-patient data. METHODS: Individual-patient data from 10 studies of chemoradiotherapy for rectal cancer were included. Pooled rates of ypN+ disease were calculated with 95 per cent confidence interval for each ypT category. Kaplan-Meier and Cox regression analyses were undertaken to assess influence of ypN status on 5-year disease-free survival (DFS) and overall survival (OS). RESULTS: Data on 1898 patients were included in the study. Median follow-up was 50 (range 0-219) months. The pooled rate of ypN+ disease was 7 per cent for ypT0, 12 per cent for ypT1, 17 per cent for ypT2, 40 per cent for ypT3, and 46 per cent for ypT4 tumours. Patients with ypN+ disease had lower 5-year DFS and OS (46.2 and 63.4 per cent respectively) than patients with ypN0 tumours (74.5 and 83.2 per cent) (P < 0.001). Cox regression analyses showed ypN+ status to be an independent predictor of recurrence and death. CONCLUSION: Risk of nodal metastases (ypN+) after chemoradiotherapy increases with advancing ypT category and needs to be considered if an organ-preserving strategy is contemplated.

When patients are diagnosed with rectal cancer and the tumour grows beyond the rectal wall there is a high risk that the tumour has spread to nearby lymph nodes. This study showed that this relationship between tumour invasion depth and lymph node involvement is similar after treatment with (chemo)radiotherapy. Patients who have tumour cells remaining in the lymph nodes after (chemo) radiotherapy have a worse prognosis than patients who do not have cancer cells remaining in the lymph nodes. When an organ-preserving treatment is considered as an alternative therapy, this should be kept in mind during patient counselling.

T2-weighted, apparent diffusion coefficient and 18F-FDG PET histogram analysis of rectal cancer after preoperative chemoradiotherapy.

BACKGROUND: The aim of our study was to investigate the correlation among T2-weighted (T2w) images, apparent diffusion coefficient (ADC) maps, 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) images, histogram analysis and the pathological response in locally advanced rectal cancer (LARC) after preoperative chemoradiotherapy (pCRT). METHODS: Patients with LARC were prospectively enrolled between February 2015 and August 2018 and underwent PET/magnetic resonance imaging (MRI). MRI included T2w and diffusion-weighted imaging (DWI)-sequences. ADC maps and PET images were matched to the T2w images. Voxel-based standardized uptake values (SUVs,) ADC and T2w-signal-intensity values were collected from the volumes of interest (VOIs) and mean, skewness and kurtosis were calculated. Spearman's correlation coefficient was applied to evaluate the correlation among the variables and tumor regression grade (TRG), T stage, N stage and fibrosis. RESULTS: Twenty-two patients with biopsy-proven LARC in the low or mid rectum were enrolled [17 males, mean age was 69 years (range 49-85 years)]. Seven patients experienced complete regression (TRG1). A significant positive correlation was found between SUV mean values (ρ = 0.480; p = 0.037) and TRG. No other significant correlations were found. CONCLUSIONS: Histogram analysis of SUV values is a predictor of TRG in LARC.

Multicentre randomized clinical trial of colonic J pouch or straight stapled colorectal reconstruction after low anterior resection for rectal cancer.

BACKGROUND: Colonic J pouch reconstruction has been found to be associated with a lower incidence of anastomotic leakage than straight anastomosis. However, studies on this topic are underpowered and retrospective. This randomized trial evaluated whether the incidence of anastomotic leakage was reduced after colonic J pouch reconstruction compared with straight colorectal anastomosis following anterior resection for rectal cancer. METHODS: This multicentre RCT included patients with rectal carcinoma who underwent low anterior resection followed by colorectal anastomosis. Patients were assigned randomly to receive a colonic J pouch or straight colorectal anastomosis. The main outcome measure was the occurrence of major anastomotic leakage. The incidence of global (major plus minor) anastomotic leakage and general complications were secondary outcomes. Risk factors for anastomotic leakage were identified by regression analysis. RESULTS: Of 457 patients enrolled, 379 were evaluable (colonic J pouch arm 190, straight colorectal arm 189). The incidence of major and global anastomotic leakage, and general complications was 14·2, 19·5 and 34·2 per cent respectively in the colonic J pouch group, and 12·2, 19·0 and 27·0 per cent in the straight colorectal anastomosis group. No statistically significant differences were observed between the two arms. In multivariable logistic regression analysis, male sex (odds ratio 1·79, 95 per cent c.i. 1·02 to 3·15; P = 0·042) and high ASA fitness grade (odds ratio 2·06, 1·15 to 3·71; P = 0·015) were independently associated with the occurrence of anastomotic leakage. CONCLUSION: Colonic J pouch reconstruction does not reduce the incidence of anastomotic leakage and postoperative complications compared with conventional straight colorectal anastomosis. Registration number NCT01110798 (http://www.clinicaltrials.gov).

Local excision in rectal cancer patients with major or complete clinical response after neoadjuvant therapy: a case-matched study.

PURPOSE: To assess the long-term oncological outcomes in patients with locally advanced rectal cancer who underwent neoadjuvant therapy followed by local or total mesorectal excision. METHODS: Patients with locally advanced rectal adenocarcinoma who received neoadjuvant therapy from 2005 to 2017 were evaluated. Those with major or complete clinical response underwent a full-thickness local excision. Kaplan-Meier estimates were used to evaluate overall, disease-free, and local recurrence-free survival of patients who underwent local excision (LE group) and were compared with a matched cohort of patients who underwent total mesorectal excision (TME group). RESULTS: Among 252 patients who received neoadjuvant therapy for rectal cancer, 51 (20.2%) underwent a local excision. At a median follow-up of 61 months, patients who underwent local excision were stoma-free in 88.2% of cases and with rectum preserved in 78.5% of cases, respectively. The estimated 5-year local, disease-free, and overall survival was 91.8% vs 97.6% (95% CI: 79.5-96.8 vs 84.6-99.6), 86.7% vs 86.4% (95% CI: 72.5-93.9 vs 70.1-94.1), and 85% vs 90% (95% CI: 69.0-93.0% vs 75.3-96.2), in the study and matched control group, respectively. None of the differences was statistically significant. CONCLUSIONS: One-fifth of patients with locally advanced rectal cancer are manageable with a rectum-sparing approach after neoadjuvant therapy. With this strategy, about 80% patients will have their rectum preserved and 90% will be without stoma at long term.

Metastatic pattern and new primary tumours after neoadjuvant therapy and surgery in rectal cancer.

AIM: Current follow-up guidelines for distant tumour recurrence after rectal cancer surgery are not defined or agreed. The aim was to elucidate the pattern of recurrence over time and provide information that could help direct a strategy for surveillance. METHOD: In all, 378 patients with locally advanced rectal cancer were treated with preoperative chemoradiotherapy and surgery with curative intent. Patients were followed up with a standard protocol, and data were prospectively collected in a dedicated database. Disease-free survival and overall survival were calculated. RESULTS: Within a median follow-up time of 75 months, rates of local and distant recurrence were 2.6% and 21.7%, respectively. Risk factors for recurrence were a baseline carcinoembryonic antigen > 5.0 ng/ml, a distance from the anal verge ≤ 5 cm, R1 resection margins, G3 grading, ypT staging > 2, positive lymph node status and a tumour regression grade of 3-5. Disease-free survival did not vary significantly between patients with lung and extra-pulmonary metastases (P = 0.59). The only factor associated with increased risk of lung metastases was a distance of the tumour from the anal verge of ≤ 5 cm (P = 0.01). Most recurrences occurred within the first 3 years after surgery (74.4%). The first site of recurrence was most frequently the lung (52.0%). The most frequent new primary malignancy was lung cancer (22.5%). CONCLUSIONS: Patients undergoing curative therapy for rectal cancer often experience distant recurrence; the majority of recurrences occur within the first 3 years after surgery and lung metastases are the most common. A predictive factor for pulmonary recurrence is a tumour in the lower rectum.

Bowel function and quality of life after local excision or total mesorectal excision following chemoradiotherapy for rectal cancer.

BACKGROUND: Local excision for rectal cancer is expected to offer a better functional outcome than conventional surgery. The aim of the present study was to compare quality of life and bowel function in patients with rectal cancer who underwent either local excision or conventional surgery after chemoradiotherapy. METHODS: This was a retrospective multicentre study. Patients who underwent local excision were compared with those who had mesorectal excision. Quality of life and bowel function were investigated using validated questionnaires (European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30, EORTC QLQ-CR29 and Memorial Sloan-Kettering Cancer Center Bowel Function Instrument) at a median follow-up of 49 (range 13-95) months. Further analysis was undertaken of data from patients who underwent local excision alone compared with those requiring subsequent radical surgery. Statistical significance was set at P < 0·010. RESULTS: The mean constipation score was significantly better in the local excision group than in the mesorectal excision group (3·8 (95 per cent c.i. 0·3 to 7·2) versus 19·8 (12·1 to 27·4); P < 0·001). Compared with patients who underwent mesorectal excision, those who had local excision had less sensation of incomplete emptying (mean score 3·7 (3·4 to 4·0) versus 2·8 (2·5 to 3·1); P < 0·001) and second bowel movements within 15 min (mean score 3·6 (3·3 to 3·9) versus 3·0 (2·7 to 3·3); P = 0·006). Patients who underwent local excision alone scored better than those who had mesorectal excision, particularly for bowel function, who, in turn, scored better than patients requiring subsequent radical surgery following local excision. CONCLUSION: Patients who underwent local excision had a better quality of life and bowel function than those who underwent mesorectal excision.

Rectal sparing approach after preoperative radio- and/or chemotherapy (RESARCH) in patients with rectal cancer: a multicentre observational study.

BACKGROUND: Rectum-sparing approaches appear to be appropriate in rectal cancer patients with a major (mCR) or complete clinical response (cCR) after neoadjuvant therapy. The aim of the present study is to evaluate the effectiveness of rectum-sparing approaches at 2 years after the completion of neoadjuvant treatment. STUDY DESIGN: Patients with rectal adenocarcinoma eligible to receive neoadjuvant therapy will be prospectively enrolled. Patients will be restaged 7-8 weeks after the completion of neoadjuvant therapy and those with mCR (defined as absence of mass, small mucosal irregularity no more than 2 cm in diameter at endoscopy and no metastatic nodes at MRI) or cCR will be enrolled in the trial. Patients with mCR will undergo local excision, while patients with cCR will either undergo local excision or watch and wait policy. The main end point of the study is to determine the percentage of rectum preservation at 2 years in the enrolled patients. CONCLUSION: This protocol is the first prospective trial that investigates the role of both local excision and watch and wait approaches in patients treated with neoadjuvant therapy for rectal cancer. The trial is registered at clinicaltrials.gov (NCT02710812).

T1 colon cancer in the era of screening: risk factors and treatment.

BACKGROUND: The aim of this study was to identify risk factors for lymph node positivity in T1 colon cancer and to carry out a surgical quality assurance audit. METHODS: The sample consisted of consecutive patients treated for early-stage colon lesions in 15 colorectal referral centres between 2011 and 2014. The study investigated 38 factors grouped into four categories: demographic information, preoperative data, indications for surgery and post-operative data. A univariate and multivariate logistic regression analysis was performed to analyze the significance of each factor both in terms of lymph node (LN) harvesting and LN metastases. RESULTS: Out of 507 patients enrolled, 394 patients were considered for analysis. Thirty-five (8.91%) patients had positive LN. Statistically significant differences related to total LN harvesting were found in relation to central vessel ligation and segmental resections. Cumulative distribution demonstrated that the rate of positive LN increased starting at 12 LN harvested and reached a plateau at 25 LN. CONCLUSIONS: Some factors associated with an increase in detection of positive LN were identified. However, further studies are needed to identify more sensitive markers and avoid surgical overtreatment. There is a need to raise the minimum LN count and to use the LN count as an indicator of surgical quality.

Surgical Unit volume and 30-day reoperation rate following primary resection for colorectal cancer in the Veneto Region (Italy).

BACKGROUND: The aim of this study was to evaluate the impact of Surgical Unit volume on the 30-day reoperation rate in patients with CRC. METHODS: Data were extracted from the regional Hospital Discharge Dataset and included patients who underwent elective resection for primary CRC in the Veneto Region (2005-2013). The primary outcome measure was any unplanned reoperation performed within 30 days from the index surgery. Independent variables were: age, gender, comorbidity, previous abdominal surgery, site and year of the resection, open/laparoscopic approach and yearly Surgical Unit volume for colorectal resections as a whole, and in detail for colonic, rectal and laparoscopic resections. Multilevel multivariate regression analysis was used to evaluate the impact of variables on the outcome measure. RESULTS: During the study period, 21,797 elective primary colorectal resections were performed. The 30-day reoperation rate was 5.5% and was not associated with Surgical Unit volume. In multivariate multilevel analysis, a statistically significant association was found between 30-day reoperation rate and rectal resection volume (intermediate-volume group OR 0.75; 95% CI 0.56-0.99) and laparoscopic approach (high-volume group OR 0.69; 95% CI 0.51-0.96). CONCLUSIONS: While Surgical Unit volume is not a predictor of 30-day reoperation after CRC resection, it is associated with an early return to the operating room for patients operated on for rectal cancer or with a laparoscopic approach. These findings suggest that quality improvement programmes or centralization of surgery may only be required for subgroups of CRC patients.

Outcome and prognostic factors of local recurrent rectal cancer: a pooled analysis of 150 patients.

BACKGROUND: Surgery is the only curative treatment in patients with locally recurrent rectal cancer (LRRC). The aim of this study was to evaluate the outcome and the prognostic factors of tumour-free resection margin (R0) and overall survival (OS) in LRRC. METHODS: Consecutive LRRC patients observed between 1987 and 2005 in three Italian university hospitals were evaluated. Survival curves were estimated using the Kaplan-Meier method and compared with the log-rank test. In order to identify factors associated with both R0 resection and OS, a logistic regression analysis was performed in patients who underwent surgery with curative intent. RESULTS: Out of 150 patients with LRRC, 107 underwent surgery, but since 7 were found to have unresectable disease only 100 underwent surgical resection. Of them, 51 underwent radical and 49 extended resection. Sixty of the 107 patients underwent multimodality treatment. In 61 patients, R0 resection was achieved. Median OS after surgery was 43.4 months. In patients, who had surgery with curative intent, independent variables associated with R0 resection were: surgery for the primary tumour performed in other hospitals (p = 0.042) extended resection (p = 0.025) and use of positron emission tomography (PET) as a staging modality (p = 0.03). Independent variables associated with OS were: post-operative radiotherapy (p = 0.004), stage of the primary tumour (p = 0.004), R0 resection (p = 0.00001), and use of PET (0.02). CONCLUSIONS: Resection for LRRC results in improved survival. Other than the well-known prognostic factors R0 resection and OS, PET scan has an independent impact both on OS and R0 resection. It should therefore be included in routine clinical practice when staging LRRC.

Large-scale phylogenomic analysis reveals the phylogenetic position of the problematic taxon Protocruzia and unravels the deep phylogenetic affinities of the ciliate lineages.

The Ciliophora is one of the most studied protist lineages because of its important ecological role in the microbial loop. While there is an abundance of molecular data for many ciliate groups, it is commonly limited to the 18S ribosomal RNA locus. There is a paucity of data when it comes to availability of protein-coding genes especially for taxa that do not belong to the class Oligohymenophorea. To address this gap, we have sequenced EST libraries for 11 ciliate species. A supermatrix was constructed for phylogenomic analysis based on 158 genes and 42,158 characters and included 16 ciliates, four dinoflagellates and nine apicomplexans. This is the first multigene-based analysis focusing on the phylum Ciliophora. Our analyses reveal two robust superclades within the Intramacronucleata; one composed of the classes Spirotrichea, Armophorea and Litostomatea (SAL) and another with Colpodea and Oligohymenophorea. Furthermore, we provide corroborative evidence for removing the ambiguous taxon Protocruzia from the class Spirotrichea and placing it as incertae sedis in the phylum Ciliophora.

Ozonation effects for excess sludge reduction on bacterial communities composition in a full-scale activated sludge plant for domestic wastewater treatment.

Activated sludge process is the most widely diffused system to treat wastewater to control the discharge of pollutants into the environment. Microorganisms are responsible for the removal of organic matter, nitrogen, phosphorous and other emerging contaminants. The environmental conditions of biological reactors significantly affects the ecology of the microbial community and, therefore, the performance of the treatment process. In the last years, ozone has been used to reduce excess sludge production by wastewater treatment plants (WWTPs), whose disposal represents one of the most relevant operational costs. The ozonation process has demonstrated to be a viable method to allow a consistent reduction in excess sludge. This study was carried out in a full-scale plant treating municipal wastewater in two parallel lines, one ozonated in the digestion tank and another used as a control. Bacterial communities of samples collected from both lines of digestion thanks were then compared to assess differences related to the ozonation treatment. Data were then analysed with terminal restriction fragment length polymorphism (T-RFLP) analysis on 16S rRNA gene. Differences between bacterial communities of both treated and untreated line appeared 2 weeks after the beginning of the treatment. Results demonstrated that ozonation treatment significantly affected the activated sludge in WWTP.

Telomerase is an independent prognostic marker of overall survival in patients with colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is an important cause of cancer-related death. Prediction of recurrence is an important issue in the treatment of disease, particularly for stage II patients. The level of telomere-specific reverse transcriptase (hTERT), the catalytic component of the telomerase complex, increases along with CRC progression, but its prognostic value is still unclear. METHODS: One hundred and thirty-seven CRC patients were studied for hTERT expression in tumour cells by real-time PCR. hTERT level was evaluated as a prognostic factor of overall survival (OS) in all patients and of disease recurrence in a subgroup of 50 stage II patients. RESULTS: The median hTERT level was 93.8 copies (interquartile range 48-254). Patients with high hTERT levels (above the median) showed a significantly worse survival than those with low hTERT levels (below the median; log-rank test P<0.0001; hazard ratio (HR)=3.30 (95% confidence interval (CI) 1.98-5.52); P<0.0001). The negative prognostic value of high hTERT level is independent of the pathological stage and microsatellite instability (HR=2.09 (95% CI 1.20-3.64), P=0.009). Moreover, in stage II CRC, high hTERT levels identified patients with a higher risk of disease recurrence (HR=3.06 (95% CI 1.03-9.04), P=0.043) and death (HR=3.24 (95% CI 1.37-7.71), P=0.008). CONCLUSION: hTERT level is an independent prognostic marker of OS in CRC patients. In addition, assessment of hTERT level could improve stratification of stage II CRC patients for the risk of disease recurrence.

Clinical and molecular features of attenuated adenomatous polyposis in northern Italy.

BACKGROUND: Attenuated familial adenomatous polyposis (AFAP) is characterized by the presence of 10-99 colorectal adenomas. The disease may be associated with mutations in either APC or MUTYH genes. We purposed to evaluate the contribution of adenomatous polyposis coli (APC) and MutY homologue (MUTYH) germline alterations to the AFAP phenotype and to identify genotype/phenotype correlations. METHODS: During counselling for familial adenomatous polyposis (FAP), 91 probands (and 107 affected individuals) who met the criteria of AFAP were identified. Eighty-two families were screened for constitutional mutations of the APC and MUTYH genes. RESULTS: MUTYH mutations were detected in 21 families (25.6 % of the 82 tested), and APC mutations in 7 (8.5 %). Overall, constitutional alterations were found in 34.1 % of the probands. Patients with APC mutations were younger at cancer onset and had a higher mean number of polyps (48.5 ± 33.0 in APC+ individuals vs. 35.7 ± 24.9 in MUTYH+ individuals, and 33.2 ± 18.4 in the "no mutation" group). Clinical features rendered the "no mutation" group closer to MUTYH+ than to the APC+ group. Colorectal cancer at diagnosis was detected in 40 % of AFAP individuals. CONCLUSIONS: AFAP is a new clinical entity with its frequency in the general population still undefined. The number of adenomas varies greatly, with an average of 30-40 lesions. The molecular basis of AFAP can be established in approximately 1/3 of the patients. Both MUTYH and APC genes are implicated in AFAP, though the role of MUTYH is of considerably greater relevance.

Clinical and molecular detection of inherited colorectal cancers in northeast Italy: a first prospective study of incidence of Lynch syndrome and MUTYH-related colorectal cancer in Italy.

The reported incidence of hereditary colorectal cancers (CRCs) is widely variable. The principal aim of the study was to prospectively evaluate the incidence of familial CRCs in a region of northern Italy using a standardized method. Consecutive CRC patients were prospectively enrolled from October 2002 to December 2003. Patients underwent a structured family history, the microsatellite instability (MSI) test and a screen for MUTYH mutations. Following family history patients were classified as belonging to high, moderate and mild risk families. Immunohistochemistry for MLH1, MSH2, MSH6 and PMS2 proteins and investigation for MLH1/MSH2 mutations, for MLH1 promoter methylation and for the V600E hotspot BRAF mutation were performed in high MSI (MSI-H) cases. Of the 430 patients enrolled, 17 (4%) were high risk [4 hereditary non-polyposis colorectal cancer (HNPCC), 12 suspected HNPCC and 1 MUTYH-associated adenomatous polyposis coli (MAP)], 53 moderate risk and 360 mild risk cases. The MSI test was performed on 393 tumours, and 46 (12%) of them showed MSI-H. In these patients, one MLH1 pathogenetic mutations and two MSH2 pathogenetic mutations were found. Thirty-two (70%) MSI-H cases demonstrated MLH1 methylation and/or BRAF mutation: None of them showed MLH1/MSH2 mutation. Two biallelic germline MUTYH mutations were found, one with clinical features of MAP. A strong family history of CRC was present in 4% of the enrolled cases; incidence of MLH1/MSH2 or MUTHY mutations was 1.3% and of MSI-H phenotype was 12%. MLH1 methylation and BRAF mutation can exclude 70% of MSI-H cases from gene sequencing.