Quantification of surgical workflow during robotic proctectomy.

BACKGROUND: Surgical workflow assessments offer insight regarding procedure variability. We utilised an objective method to evaluate workflow during robotic proctectomy (RP). METHODS: We annotated 31 RPs and used Spearman's correlation to measure the correlation of step time and step visit frequency with console time (CT) and total operative time (TOT). RESULTS: Strong correlations were seen with CT and step times for inferior mesenteric vein dissection and ligation (ρ = 0.60, ρ = 0.60), lateral-to-medial splenic flexure mobilisation (SFM) (ρ = 0.63), left rectal dissection (ρ = 0.64) and mesorectal division (ρ = 0.71). CT correlated strongly with medial-to-lateral (ρ = 0.75) and supracolic SFM visit frequency (ρ = 0.65). TOT correlated strongly with initial exposure time (ρ = 0.60), and medial-to-lateral (ρ = 0.67) and supracolic SFM visit frequency (ρ = 0.65). CONCLUSION: This study correlates surgical steps with CT and TOT through standardised annotation, providing an objective approach to quantify workflow.

Robotic Proctectomy: Beyond the Initial Learning Curve.

BACKGROUND: Multiple authors have described an initial learning curve (LC) for robotic proctectomy (RP), but there is scant literature regarding continued technical progression beyond this stage. Total operating time is the most commonly used metric to measure proficiency. Our goal was to examine RP experience after the initial LC looking for evidence of further technical progression. METHODS: We reviewed our robotic surgery database for a single surgeon during operations 100 through 550 to identify 83 RPs for tumor. These were divided into quartiles by series order, indicating surgeon experience level over time. Demographics and outcomes were compared among the groups. We defined percent console time (PCT) as a new metric. PCT was defined as console time divided by total operative time (TOT). RESULTS: From March 2014 through March 2019, 450 robotic colorectal operations were performed, including 83 RPs for polyp or cancer. No significant differences were found among the quartiles in regard to demographics, tumor features, hospital stay, conversions, or readmissions. As experience was gained, there were significant increases in intracorporeal anastomosis (ICA), TOT, and PCT. Complications decreased with experience. Number of lymph nodes in the specimen increased. On multivariate analysis, later experience group, body mass index ≥30, and ICA were associated with increased PCT. DISCUSSION: ICA became a routine part of RP after the initial LC, with increases in TOT and PCT. Number of lymph nodes increased and number and severity of complications decreased with experience. Increased PCT may indicate increased expertise during RP.

Advanced Intestinal Cancers often Maintain a Multi-Ancestral Architecture.

A widely accepted paradigm in the field of cancer biology is that solid tumors are uni-ancestral being derived from a single founder and its descendants. However, data have been steadily accruing that indicate early tumors in mice and humans can have a multi-ancestral origin in which an initiated primogenitor facilitates the transformation of neighboring co-genitors. We developed a new mouse model that permits the determination of clonal architecture of intestinal tumors in vivo and ex vivo, have validated this model, and then used it to assess the clonal architecture of adenomas, intramucosal carcinomas, and invasive adenocarcinomas of the intestine. The percentage of multi-ancestral tumors did not significantly change as tumors progressed from adenomas with low-grade dysplasia [40/65 (62%)], to adenomas with high-grade dysplasia [21/37 (57%)], to intramucosal carcinomas [10/23 (43%]), to invasive adenocarcinomas [13/19 (68%)], indicating that the clone arising from the primogenitor continues to coexist with clones arising from co-genitors. Moreover, neoplastic cells from distinct clones within a multi-ancestral adenocarcinoma have even been observed to simultaneously invade into the underlying musculature [2/15 (13%)]. Thus, intratumoral heterogeneity arising early in tumor formation persists throughout tumorigenesis.

Colon Tumors with the Simultaneous Induction of Driver Mutations in APC, KRAS, and PIK3CA Still Progress through the Adenoma-to-carcinoma Sequence.

Human colorectal cancers often possess multiple mutations, including three to six driver mutations per tumor. The timing of when these mutations occur during tumor development and progression continues to be debated. More advanced lesions carry a greater number of driver mutations, indicating that colon tumors might progress from adenomas to carcinomas through the stepwise accumulation of mutations following tumor initiation. However, mutations that have been implicated in tumor progression have been identified in normal-appearing epithelial cells of the colon, leaving the possibility that these mutations might be present before the initiation of tumorigenesis. We utilized mouse models of colon cancer to investigate whether tumorigenesis still occurs through the adenoma-to-carcinoma sequence when multiple mutations are present at the time of tumor initiation. To create a model in which tumors could concomitantly possess mutations in Apc, Kras, and Pik3ca, we developed a novel minimally invasive technique to administer an adenovirus expressing Cre recombinase to a focal region of the colon. Here, we demonstrate that the presence of these additional driver mutations at the time of tumor initiation results in increased tumor multiplicity and an increased rate of progression to invasive adenocarcinomas. These cancers can even metastasize to retroperitoneal lymph nodes or the liver. However, despite having as many as three concomitant driver mutations at the time of initiation, these tumors still proceed through the adenoma-to-carcinoma sequence.

Palliative surgery for malignant bowel obstruction from carcinomatosis: a systematic review.

IMPORTANCE: Care of patients with malignant bowel obstruction caused by peritoneal metastases may present an ethical dilemma for surgeons when nonoperative management fails. OBJECTIVE: To characterize outcomes of palliative surgery for malignant bowel obstruction from peritoneal carcinomatosis to guide decision making about surgery and postoperative interventions for patients with terminal illness. EVIDENCE REVIEW: We searched PubMed, EMBASE, Cochrane Library, Web of Knowledge, Cumulative Index to Nursing and Allied Health Literature Plus, and Google Scholar and performed manual searches of selected journals from inception to August 30, 2012, with no filters, limits, or language restrictions. We used database-specific combinations of the terms intestinal obstruction, malignant, surgery or surgical, and palliat*. We included studies reporting outcomes after palliative surgery for malignant bowel obstruction from peritoneal carcinomatosis from any primary malignant neoplasm and excluded case studies, curative surgery, isolated percutaneous procedures, stenting for intraluminal lesions, and studies in which benign and malignant obstructions could not be distinguished. We assessed quality with the Newcastle-Ottawa Scale. FINDINGS: We screened 2347 unique articles, selected 108 articles for full-text review, and included 17 studies. Surgery was able to palliate obstructive symptoms for 32% to 100% of patients, enable resumption of a diet for 45% to 75% of patients, and facilitate discharge to home in 34% to 87% of patients. Mortality was high (6%-32%), and serious complications were common (7%-44%). Frequent reobstructions (6%-47%), readmissions (38%-74%), and reoperations (2%-15%) occurred. Survival was limited (median, 26-273 days), and hospitalization for surgery consumed a substantial portion of the patient's remaining life (11%-61%). CONCLUSIONS AND RELEVANCE: Although palliative surgery can benefit patients, it comes at the cost of high mortality and substantial hospitalization relative to the patient's remaining survival time. Preoperatively, surgeons should present realistic goals and limitations of surgery. For patients choosing surgery, clarifying preferences for aggressive postoperative interventions preoperatively is critical given the high complication rate and limited survival after surgery for malignant bowel obstruction.

Dynamic tumor growth patterns in a novel murine model of colorectal cancer.

Colorectal cancer often arises from adenomatous colonic polyps. Polyps can grow and progress to cancer, but may also remain static in size, regress, or resolve. Predicting which polyps progress and which remain benign is difficult. We developed a novel long-lived murine model of colorectal cancer with tumors that can be followed by colonoscopy. Our aim was to assess whether these tumors have similar growth patterns and histologic fates to human colorectal polyps to identify features to aid in risk stratification of colonic tumors. Long-lived Apc(Min/+) mice were treated with dextran sodium sulfate to promote colonic tumorigenesis. Tumor growth patterns were characterized by serial colonoscopy with biopsies obtained for immunohistochemistry and gene expression profiling. Tumors grew, remained static, regressed, or resolved over time with different relative frequencies. Newly developed tumors demonstrated higher rates of growth and resolution than more established tumors that tended to remain static in size. Colonic tumors were hyperplastic lesions (3%), adenomas (73%), intramucosal carcinomas (20%), or adenocarcinomas (3%). Interestingly, the level of ß-catenin was higher in adenomas that became intratumoral carcinomas than those that failed to progress. In addition, differentially expressed genes between adenomas and intramucosal carcinomas were identified. This novel murine model of intestinal tumorigenesis develops colonic tumors that can be monitored by serial colonoscopy, mirror growth patterns seen in human colorectal polyps, and progress to colorectal cancer. Further characterization of cellular and molecular features is needed to determine which features can be used to risk-stratify polyps for progression to colorectal cancer and potentially guide prevention strategies.

Surgeon-reported conflict with intensivists about postoperative goals of care.

OBJECTIVE: To examine surgeons' experiences of conflict with intensivists and nurses about goals of care for their postoperative patients. DESIGN: Cross-sectional incentivized US mail-based survey. SETTING: Private and academic surgical practices. PARTICIPANTS: A total of 2100 vascular, neurologic, and cardiothoracic surgeons. MAIN OUTCOME MEASURES: Surgeon-reported rates of conflict with intensivists and nurses about goals of care for patients with poor postsurgical outcomes. RESULTS: The adjusted response rate was 55.6%. Forty-three percent of surgeons reported sometimes or always experiencing conflict about postoperative goals of care with intensivists, and 43% reported conflict with nurses. Younger surgeons reported higher rates of conflict than older surgeons with both intensivists (57% vs 32%; P = .001) and nurses (48% vs 33%; P = .001). Surgeons practicing in closed intensive care units reported more frequent conflict than those practicing in open intensive care units (60% vs 41%; P = .005). On multivariate analysis, the odds of reporting conflict with intensivists were 2.5 times higher for surgeons with fewer years of experience compared with their older colleagues (odds ratio, 2.5; 95% CI, 1.6-3.8) and 70% higher for reporting conflict with nurses (odds ratio, 1.7; 95% CI, 1.1-2.6). The odds of reporting conflict with intensivists about goals of postoperative care were 40% lower for surgeons who primarily managed their intensive care unit patients than for those who worked in a closed unit (odds ratio, 0.60; 95% CI, 0.40-0.96). CONCLUSIONS: Surgeons regularly experience conflict with critical care clinicians about goals of care for patients with poor postoperative outcomes. Higher rates of conflict are associated with less experience and working in a closed intensive care unit.