Learning curve analysis for lateral pelvic lymph node dissection in rectal cancers – Outcomes improve with experience

IntroductionLateral pelvic lymph node dissection (LPLND) is a technically challenging procedure and its learning curve has not been analysed against an oncologically relevant outcome. The purpose of the study was to determine the learning curve for LPLND in rectal cancers using nodal retrieval as performance measure.MethodsConsecutive LPLND for rectal adenocarcinomas from a single institution were retrospectively analysed. Cumulative sum (CUSUM) control charts were used to detect difference in performance with respect to lymph node yield. Negative binomial regression was used to determine factors influencing nodal harvest using Incidence Risk Ratios (IRR). Separate CUSUM curves were generated for open and minimally invasive surgeries (MIS).ResultsOne-hundred and twenty patients were included and all received preoperative radiation. MIS was used in 53.3%. Median lymph node yield was 6 with 20% nodal positivity. Increasing experience (IRR – 1.196) and MIS (IRR – 1.586) were the only factors that influenced nodal harvest. CUSUM charts revealed that learning curve was achieved after the 83rd case overall and after the 19 operations in MIS. There was a 20% increase in nodal yield after every 30 MIS LPLND performed.ConclusionsLearning curve for LPLND is relatively long and only increasing experience and minimally invasive operations increased nodal yield.     

Redefining synchronous colorectal cancers based on tumor clonality

To analyze the possible clonal origin of a part of Synchronous colorectal cancer (SCRC), we studied 104 paired-SCRCs from 52 consecutive patients without hereditary forms of CRC. We used a Single-Nucleotide Polymorphism array to characterize the genomic profiles, and subsequently used a statistical application to define them according to clonality within the same individual. We categorized the ensuing groups according to colonic location to identify differential phenotypes. The SCRC Monoclonal group (M) (19 cases) was divided into Monosegmental (MM) and Pancolonic (MP) groups. The SCRC Polyclonal group (P) (33 cases) was also divided into Monosegmental (PM) and Pancolonic (PP), the first exhibiting preference for left colon. The MM group showed a high rate of mucinous tumors, the lowest mean-number of tumors and associated-polyps, and the worst prognosis. The MP group included the largest mean-number of associated-polyps, best prognosis and familial cancer component. The PM group seemed to be a “frontier” group. Finally, the PP group also exhibited a mucin component, the highest mean-number of tumors (4.6) compared with the mean-number of polyps (7.7), poor prognosis and sporadic cases. Most relevant differential genomic regions within M groups were gains on 1q24 and 8q24, and deletions on 1p21 and 1p23 for MM, while within P were the gains on 7q36 and deletions on 1p36 for PM. The statistical application employed seems to define clonality more accurately in SCRC -more likely to be polyclonal in origin-, and together with the tumor locations, helped us to configure a classification with prognostic and clinical value.     

Lymphatic spread of T2 gallbladder carcinoma: Regional lymphadenectomy is required independent of tumor location

BackgroundThis study aimed to investigate the incidence and distribution of regional lymph node metastasis according to tumor location, and to clarify whether tumor location could determine the extent of regional lymphadenectomy in patients with pathological T2 (pT2) gallbladder carcinoma.MethodsIn total, 81 patients with pT2 gallbladder carcinoma (25 with pT2a tumors and 56 with pT2b tumors) who underwent radical resection were enrolled. Tumor location was determined histologically in each gallbladder specimen.ResultsSurvival after resection was significantly worse in patients with pT2b tumors than those with pT2a tumors (5-year survival, 72% vs. 96%; p = 0.027). Tumor location was an independent prognostic factor on multivariate analysis (hazard ratio, 14.162; p = 0.018). The incidence of regional lymph node metastasis was significantly higher in patients with pT2b tumors than in those with pT2a tumors (46% vs. 20%; p = 0.028). However, the number of positive nodes was similar between the two groups (median, 2 vs. 2; p = 0.910). For node-positive patients with pT2b tumors, metastasis was found in every regional node group (12%–63%), whereas even for node-positive patients with pT2a tumors, metastasis was observed in regional node groups outside the hepatoduodenal ligament.ConclusionsTumor location in patients with pT2 gallbladder carcinoma can predict the presence or absence of regional lymph node metastasis but not the number and anatomical distribution of positive regional lymph nodes. The extent of regional lymphadenectomy should not be changed even in patients with pT2a tumors, provided that they are fit enough for surgery.     

Impact of primary tumor location on outcome of liposarcoma patients,a retrospective cohort study

BackgroundTumor location as a prognostic factor for patients with liposarcoma (LPS) has been studied modestly with varying outcomes. The aim was to establish the impact of tumor location on recurrence and survival of LPS patients.MethodsA retrospective database of patients treated for LPS until December 2017 was used to assess 5-year local recurrence-free survival (LRFS), distant metastasis-free survival (DMFS) and disease-specific survival (DSS) per tumor location using the Kaplan-Meier method and log-rank test. A multivariable Cox regression analysis was performed to adjust for other prognostic factors.ResultsIn total, 518 patients were identified with a median follow-up of 68 months (interquartile range 31–138). Patients with retroperitoneal/intrathoracic WDLPS or DDLPS (p = 0.014), or testicular WDLPS (p = 0.026) developed a local recurrence more often than patients with other tumor locations. No differences between LPS subtypes and tumor location in the development of metastases (p = 0.600) was observed. Five-year LRFS differed significantly between tumor locations (p < 0.001) as well as 5y-DSS (p < 0.001), but 5y-DMFS did not (p = 0.241), with retroperitoneal/intrathoracic LPS having a worse prognosis. Patients with WDLPS in the extremity, trunk or testicular region did not die of disease, except for the rare occasion of dedifferentiation upon recurrence. After adjustment for other prognostic factors, tumor location was only of prognostic value for DSS (retroperitoneal/intrathoracic vs. extremity: HR 5.08, 95% CI 2.41–10.71, p < 0.001).ConclusionFor all tumor locations, DSS mimicked DMFS except for retroperitoneal/intrathoracic LPS, where DSS mimicked LRFS and where DSS was worse than DMFS. This implies that these patients die of local disease instead of metastatic disease.     

Simulação de manejo de via aérea difícil para residentes: estudo comparativo prospectivo

Background and objectivesProcedural simulation training for difficult airway management offers acquisition opportunities. The hypothesis was that 3 hours of procedural simulation training for difficult airway management improves: acquisition, behavior, and patient outcomes as reported 6 months later.MethodsThis prospective comparative study took place in two medical universities. Second‐year residents of anesthesiology and intensive care from one region participated in 3 h procedural simulation (intervention group). No intervention was scheduled for their peers from the other region (control). Prior to simulation and 6 months later, residents filled‐out the same self‐assessment form collecting experience with different devices. The control group filled‐out the same forms simultaneously. The primary endpoint was the frequency of use of each difficult airway management device within groups at 6 months. Secondary endpoints included modifications of knowledge, skills, and patient outcomes with each device at 6 months. Intervention cost assessment was provided.Results44 residents were included in the intervention group and 16 in the control group. No significant difference was observed for the primary endpoint. In the intervention group, improvement of knowledge and skills was observed at 6 months for each device, and improvement of patient outcomes was observed with the use of malleable intubation stylet and Eschmann introducer. No such improvement was observed in the control group. Estimated intervention cost was 406€ per resident.ConclusionsA 3 h procedural simulation training for difficult airway management did not improve the frequency of use of devices at 6 months by residents. However, other positive effects suggest exploring the best ratio of time/acquisition efficiency with difficult airway management simulation.ClinicalTrials.gov IdentifierNCT02470195.