1,720,971 research outputs found
Sentinel Lymph Node in Rectal Cancer: Role of Transanal Endoscopic Microsurgery
No full textL'abstract è presente nell'allegato / the abstract is in the attachmen
Oncologic and survival outcomes of pT2N0 rectal adenocarcinoma treated by transanal local excision: a retrospective cohort study
Full text linkBackground: The optimal management of pT2N0 rectal adenocarcinoma remains controversial, especially when tumours are incidentally diagnosed after local excision. Although total mesorectal excision (TME) is the standard approach, its associated morbidity has led to the exploration of conservative strategies. This study compares oncologic outcomes amongst three post-excision management options: salvage surgery, adjuvant radiotherapy, and no further treatment. Methods: This retrospective cohort comprised 90 patients with pT2N0 rectal adenocarcinoma who were treated by transanal excision at a single tertiary centre from 1993 to 2025. All patients were staged N0 on MRI and divided into three groups: Group A (no further treatment), Group B (adjuvant radiotherapy), and Group C (completion salvage surgery). The primary outcomes were overall survival (OS) and disease-free survival (DFS), with additional analyses of histopathologic prognostic factors. Results: Median follow-up was 31 months. OS varied significantly across groups (p = 0.015), with the highest survival in Group B, followed by Group C and Group A. DFS showed no significant difference between groups. Patients in Group B had the lowest mortality (8.7%) and recurrence (30.4%) rates. Tumour budding was a significant predictor of poor prognosis in multivariate analysis. Local excision alone was associated with higher recurrence and mortality rates. Conclusion: In selected patients with pT2N0 rectal cancer discovered after transanal excision, adjuvant radiotherapy may provide outcomes comparable to salvage surgery and serve as an alternative in patients not suitable for surgery. High-risk histopathologic features should inform further management, as local excision alone was associated with worse outcomes. Multidisciplinary evaluation remains crucial for treatment planning
Should be a locally advanced colon cancer still considered a contraindication to laparoscopic resection?
Full text linkBackground The role of elective laparoscopic resection (LR) for the treatment of locally advanced colon cancer (LACC) is unclear. Most studies have retrospectively investigated the outcomes of LR for pT4 cancers, while clinical T4 (cT4) cancers are excluded in the large randomized controlled trials comparing LR and open resection (OR). The aim of this study was to investigate the outcomes in patients undergoing elective LR for LACC. Methods A prospective single-institution database including consecutive patients undergoing elective LR for clinical LACC (high-risk T3 or T4 N0-2) between March 1996 and March 2017 was retrospectively reviewed. A multivariate analysis was performed to identify predictors of conversion to OR and risk factors for adverse oncologic outcomes. Results A total of 300 patients undergoing LR for LACC were included. A multi-visceral resection was needed in 17 (5.7%) patients. A total of 63 (21%) LRs were converted to OR, mainly due to suspected adjacent organ invasion (82.5%) or obesity (9.5%). Overall postoperative Clavien-Dindo 3-4 complication rate was 4.7%, with no significant differences between completed and converted LRs. Final pathology showed 18 (6%) pT2, 215 (71.7%) pT3, 54 (18%) pT4a, and 13 (4.3%) pT4b cancers. A R0 resection was achieved in 98.3% of patients. On multivariate analysis, tumor size >= 7 cm and tumor site (splenic flexure) were the independent risk factors for conversion to OR. A pT4 colon cancer and LNR of 0.25 or greater, but not conversion to OR, were independently associated with both poorer OS and DFS. Conclusion(s) Clinical LACC should not be considered a contraindication to LR itself. Bulky tumors >= 7 cm and splenic flexure cancers are at higher risk of conversion to OR; however, there is no increased postoperative morbidity or adverse oncologic outcomes in converted patients
Hybrid laparo-endoscopic techniques for challenging colorectal lesions: a systematic review
Full text linkBackground: Colorectal cancer screening has increased the detection of polyps requiring resection, but standard endoscopic techniques such as endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) are often unsuitable for large, fibrotic, or anatomically challenging lesions. Segmental colectomy remains definitive but carries substantial morbidity, particularly for benign disease. Laparo-endoscopic cooperative surgery (LECS) and related hybrid techniques have emerged as minimally invasive alternatives bridging the gap between endoscopic and surgical resection. Methods: A systematic review was performed according to PRISMA guidelines, querying PubMed, Embase, and Cochrane databases (1985-2024). Studies reporting combined laparoscopic-endoscopic resections for colorectal lesions unsuitable for standard endoscopic treatment were included. Outcomes assessed included additional surgery, adenocarcinoma detection, complication rates, surgery for complications, conversion to open surgery, and recurrence. Random-effects models were used to calculate pooled proportions and 95% confidence intervals (CIs). Results: Twenty-seven studies encompassing 1112 patients were included. The pooled rate of additional surgery was 5% (95% CI 3-8%; I2 = 0%), including 7% (95% CI 5-9%) for oncologic indications. Adenocarcinoma was identified in 12% of resected lesions (95% CI 8-16%), underscoring limitations of preoperative staging. Overall complications occurred in 7% (95% CI 5-10%), with surgery for complications required in only 1% (95% CI 0-2%). Conversion to open surgery occurred in 2% (95% CI 1-3%). Long-term follow-up demonstrated a local recurrence rate of 3% (95% CI 2-6%; I2 = 0%). Conclusions: Hybrid laparoscopic-endoscopic resections are safe, effective, and reproducible options for complex colorectal lesions not amenable to standard endoscopic resection. These techniques achieve low complication and recurrence rates while preserving bowel and minimizing morbidity associated with colectomy. Given the 12% incidence of unexpected adenocarcinoma, intraoperative adaptability and multidisciplinary expertise are essential. Prospective multicenter studies with standardized reporting are needed to refine patient selection and confirm long-term oncologic safety
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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