Number Of Central Nodes Research Articles

Risk factors for skip metastasis and lateral lymph node metastasis of papillary thyroid cancer

BackgroundLymph node metastases from papillary thyroid cancer is believed to disseminate sequentially, first to the central neck and later to the lateral neck. Skip metastases of papillary thyroid cancer, however, are defined as lateral lymph node metastasis without central lymph node metastasis. The aim of this study was to investigate the risk factors for skip metastases and lateral lymph node metastasis of papillary thyroid cancer. MethodsWe reviewed 721 papillary thyroid cancer patients undergoing total thyroidectomy with central lymph node dissection and lateral lymph node dissection during 2013 to 2018. Multivariate logistic regression analysis was performed to identify clinicopathologic risk factors for skip metastasis and lateral lymph node metastasis of papillary thyroid cancer. ResultsThe rate of skip metastases was 7.4% (42 of 567 patients). Multivariate analysis showed that female sex and papillary thyroid microcarcinoma (≤ 1 cm) were independent risk factors for skip metastases, with odds ratios ([OR], 95% confidence interval [CI]) of 2.29 (1.02–5.16) and 2.84 (1.46–5.16), respectively. Intrathyroidal spread of papillary thyroid cancer and an increased number of central lymph nodes dissected were inversely associated with skip metastases with ORs (95% CI) of 0.13 (0.02–0.99) and 0.88 (0.83–0.94), respectively. In contrast, a greater tumor size, central lymph node metastasis, an increased number of central lymph nodes dissected, and an increased number of lateral lymph nodes dissected were associated with a lateral lymph node metastasis risk of papillary thyroid cancer, with ORs (95% CI) as follow: 1.67 (1.08–2.59), 3.07 (1.71–5.52), 1.25 (1.14–1.37), and 1.07 (1.04–1.10), respectively, by multivariate analysis. ConclusionGreater tumor size, central lymph node metastasis, and an increased number of both central lymph nodes and lateral lymph nodes dissected were predictors for lateral lymph node metastasis of papillary thyroid cancer. In addition, papillary thyroid microcarcinoma was an independent risk factor for skip metastases. A complete and comprehensive central compartment dissection may decrease the false-positive detection of skip metastases of papillary thyroid cancer.

Short and Long-Term Potential Role of Carbon Nanoparticles in Total Thyroidectomy with Central Lymph Node Dissection

Whether we should use carbon nanoparticle (CN) routinely in thyroid surgery is still controversial. 406 papillary thyroid cancer (PTC) patients who underwent total thyroidectomy (TT) with bilateral central lymph node dissection (CLND) from January 2010 to December 2012 were retrospectively analyzed. The incidence of transient hypoparathyroidism and hypocalcemia in CN group was significantly lower than the control group at second, fifth day after surgery (P = 0.004, 0.042, 0.002 and 0.045 respectively). However, no significant difference existed between the two groups about the permanent hypoparathyroidism and hypocalcemia (P = 1.000). Total number of central lymph nodes and metastatic lymph nodes in CN group were more than those in control group (P = 0.031 and 0.038 respectively). However, recurrence was not significantly different between the two groups after at least 5-year follow up (P = 0.7917). In the subgroup of prophylactic and therapeutic CLND study, no significant difference existed between the two groups (P = 0.5295 and 0.8459 respectively). CN significantly help in identifying the parathyroid glands in surgery and increased the number of lymph nodes in central compartment. However, we should not exaggerate the function of CN since it couldn’t improve the permanent hypoparathyroidism and recurrence in PTC patients who underwent TT with bilateral CLND.

Carbon nanoparticles facilitate lymph nodes dissection and parathyroid glands identification in reoperation of papillary thyroid cancer.

The aim of the study was to investigate whether carbon nanoparticles (CNs) can improve the dissection of lymph nodes and protect parathyroid glands (PGs) during reoperation for patients with papillary thyroid carcinoma (PTC).PTC patients who previously underwent thyroidectomy and later received reoperation between January 2009 and January 2016 were retrospectively recruited. We compared the patients who had CN suspension injected into the residual thyroid gland with a control group of patients who did not have the injection. The primary endpoints were the number of lymph nodes dissected, the number of PGs identified and reimplanted, and the rate of postoperative hypoparathyroidism.CN suspension injection was conducted in 55 of 174 patients. The total number of lymph nodes and metastatic lymph nodes dissected between the 2 groups were not different (22.8 ± 13.7 vs 21.0 ± 13.3, P = .481 and 5.5 ± 3.8 vs 4.8 ± 4.0, P = .695). The number of central lymph nodes and metastatic central lymph nodes in the CN group was significantly higher than those dissected in the control group (8.7 ± 6.9 vs 6.2 ± 5.2, P = .037 and 2.7 ± 1.9 vs 2.1 ± 1.6, P = .012). More PGs were identified (2.42 ± 1.15 vs 1.58 ± 1.12, P = .001) and fewer were reimplanted (48 vs 90, P = .040) in the CN group. Patients who had CN suspension injection had a lower rate of transient hypoparathyroidism (14/55 vs 50/119, P = .043) but no significant difference in the rate of permanent hypoparathyroidism (1/55 vs 9/119, P = .173).CN suspension injection improves dissection of central lymph nodes and identification of PG in PTC patients undergoing reoperation and lowers the rate of postoperative transient hypoparathyroidism.

Laparoscopic complete mesocolic excision (CME) with completely medial approach for right-hemi colon cancer

Laparoscopic complete mesocolic excision (CME) has the potential to become the standard procedure of colon cancer surgery for its lower local recurrence rate and improved prognosis. Completely medial approach (CMA) is a promising access of laparoscopic CME in right hemicolectomy. A 45-year-old female patient was diagnosed as right-hemi colon cancer. Based on this case, we share the surgical strategies of laparoscopic CME with completely medial access combined with our previous study. Laparoscopic CME emphasized on en bloc resection of mesocolon without defections to the planes. Besides, further dissection is needed for cancer at the hepatic flexure, which involves subpyloric lymph nodes and of greater omentum that is within 15 cm of the tumor and along the greater curvature. The operation time was 128 min and the blood loss was 10 mL. The total number of central lymph nodes retrieved was 19. The time for passage of flatus and hospitalization were 2 and 12 days respectively. Laparoscopic CME with completely medial access is technically feasible, and should be conducted by experienced hand in right hemicolectomy.

Bilateral axillo-breast approach robotic thyroidectomy: review of evidences.

The bilateral axillo-breast approach (BABA) is one of the most popular contemporary remote-access thyroidectomy techniques. While the initial experiences with BABA endoscopic thyroidectomy (ET) were associated with some technical challenges and safety concerns, many limitations of the technique could now be substantially overcome by BABA robotic thyroidectomy (RT). In this review, the current literature evidences of BABA RT were analyzed. Data regarding the patient selection, the learning curve, and the comparison with open thyroidectomy (OT) and BABA ET were examined. Careful case selection for BABA RT should be undertaken according to factors related to the patient and the thyroid pathology. The learning curve of BABA RT was about 40 cases. Comparing to OT, BABA RT was comparable to OT for the complication profiles and most perioperative outcomes. But it was associated with longer operative time, higher cost and possibly inferior oncological control with lower number of central lymph node (LN) retrieved. When compared to BABA ET, BABA RT was comparable for most perioperative outcomes except longer operative time and higher cost. Yet, BABA RT was superior to BABA ET for better oncological control. BABA RT is a safe and effective procedure for most benign thyroid conditions and low-risk differentiated thyroid cancers (DTC).

Risk factors for central neck lymph node metastases in papillary thyroid microcarcinoma.

e17583 Background: Papillary thyroid microcarcinoma (PTMC) accounts for nearly half of all cases of thyroid papillary cancer. Although PTMC has a good prognosis, lymph node metastasis, especially central lymph node metastasis (CLNM), is the leading cause of local recurrence. The value of central lymph node dissection in PTMC remains controversial. Few studies have focused on the relationship between CLNM and multifocality in PTMC. This retrospective study of a large cohort of patients with PTMC aimed to identify assess the predictive value of multifocality for identifying patients at high risk of CLNM who may benefit from central lymph node dissection. Methods: Patients with PTMC who underwent total or hemi-thyroidectomy with effective unilateral or bilateral central lymph node dissection at Zhejiang Caner Hospital between January 2007 and December 2015 were enrolled ( n = 3543). Number and laterality of PTMC foci, extrathyroidal extension (ETE), tumor size, age, sex, positive/total number of central lymph nodes and other clinicopathological factors were recorded. The chi-square test was used for univariate analysis; logistic regression, for multivariate analysis. Results: Multifocality, age, sex, tumor size, ETE and nodular goiter were significantly associated with central lymph node metastasis (CLNM) in univariate analysis. Multifocality was an independent predictive factor for CLNM in multivariate analysis. Compared to unifocal disease, the odds ratio (OR) for CLNM was 1.447 for patients with ¡Ý 2 tumor foci ( P < 0.001) and 2.978 for patients with ¡Ý 3 tumor foci ( P < 0.001). Conclusions: Multifocality with ¡Ý 3 tumor foci was an independent predictive factor for CLNM in PTMC. Multifocality should be assessed when selecting patients for prophylactic central neck lymph node dissection, and we recommend patients with multifocality should undergo more radical treatment.

Application of carbon nanoparticles accelerates the rapid recovery of parathyroid function during thyroid carcinoma surgery with central lymph node dissection: A retrospective cohort study

Background and ObjectivesThe aim of this study was to evaluate the efficacy of carbon nanoparticles in identifying lymph nodes and promoting parathyroid gland function recovery after thyroid carcinoma surgery along with central lymph node dissection. MethodsA total of 231 patients who underwent thyroid carcinoma surgery combined with central lymph node dissection were divided into two groups: the CN group (intraoperative carbon nanoparticles injections) and the control group (no injection). Datas were collected respectively on the pre-operative, 1st, 7th and 30th postoperative days and monthly thereafter. While the pathological results (e.g. amount of incidental removed parathyroid glands and lymph nodes dissected), complications (e.g. rates of vocal cord paralysis, the neuromuscular symptoms, hypocalcemia and hypoparathyroidism), as well as follow-up outcomes of the serum Ca2+ and PTH levels were gathered and measured to be included in. ResultsIn regard to the results of the pathological tests, the control group had a relatively higher incidence of incidental parathyroidectomy when compared to the CN group (P < 0.05). The mean number of central lymph nodes dissected was rather higher in the CN group than that of the control group (P < 0.05).With respect to the follow-up results, the CN group had an earlier and faster recovery of serum PTH levels as compared to the control group (P < 0.05). The serum PTH levels of the CN group were apparently higher than that of the control group at the first week and month postoperatively (P < 0.05). No significant differences were found in rates of long-term postoperative complications between the two groups (P > 0.05). ConclusionCarbon nanoparticles play a key role in accurately identifying lymph nodes, reducing mistaken excision of parathyroid glands, accelerating rapid recovery of parathyroid function during thyroid carcinoma surgery with central lymph node dissection, without increasing the probability of postoperative complications.

Propensity score-matched analysis of robotic versus endoscopic bilateral axillo-breast approach (BABA) thyroidectomy in papillary thyroid carcinoma

The da Vinci surgical robot system was developed to overcome the weaknesses of endoscopic surgery. However, whether robotic surgery is superior to endoscopic surgery remains uncertain. Therefore, the purpose of this study was to compare the surgical and oncologic outcomes between endoscopic and robotic thyroidectomy using bilateral axillo-breast approach (BABA). Between January 2008 and June 2015, papillary thyroid carcinoma patients who underwent thyroidectomy with central neck dissection using endoscopic (n=480) or robotic (n=705) BABA were primarily reviewed. We performed 1:1 propensity score matching and 289 matched pairs were yielded. Operation time was significantly longer in the robotic thyroidectomy than in the endoscopic thyroidectomy (184.9 vs. 128.9min, P<0.001). A significantly higher number of central lymph nodes (CLNs) were resected in the robotic thyroidectomy than in the endoscopic thyroidectomy (5.3 vs. 4.4, P=0.003). However, the incidence of other outcomes including hospital stay, postoperative duration, thyroglobulin level, radioactive iodine ablation, hemorrhage, chyle leakage, wound infection, recurrent laryngeal nerve injury, and loco-regional recurrence did not significantly differ between the endoscopic thyroidectomy and the robotic thyroidectomy. Endoscopic thyroidectomy is comparable with robotic thyroidectomy in view of surgical complications and LRR. Because robotic thyroidectomy resected a larger number of CLNs than did endoscopic thyroidectomy, further long-term follow-up studies will be required to clarify the possible prognostic benefits of robotic thyroidectomy.

Evaluating the influence of prophylactic central neck dissection on TNM staging and the recurrence risk stratification of cN0 differentiated thyroid carcinoma

The purpose of this study was to explore the risk factors that were associated with central lymph node metastasis (CLNM) in patients with clinical nodal negative differentiated thyroid carcinoma (cN0 DTC) after prophylactic central neck dissection (pCND). The influence of pCND on TNM staging and recurrence risk stratification (RRS) in patients with cN0 DTC was also evaluated in our study. A total of 153cN0 DTC patients in Guangdong general hospital who underwent thyroidectomy with pCND from March2014 to October2014 were enrolled in this study. The relations of CLNM with clinicopathologic characteristics of cN0 DTC were analyzed by univariate and multivariate logistic regression. The influence of pCND on migration of TNM staging and RRS in cN0 DTC was observed. In the present study, CLNM was found in 42.5% (65 of 153cases) of patients with cN0 DTC. On univariate analysis, the age less than 45years old, tumor size more than 2cm, pT staging, and a total number of central lymph nodes dissected more than 3 were significantly associated with CLNM (P<0.05); however, gender, tumors affecting both lobes, multifocality, capsular invasion, and Hashimoto's thyroiditis were not related with CLNM (P>0.05). On multivariate logistic regression, age<45years (P=0.001) and a total number of central lymph nodes dissected >3(P=0.002) were significantly associated with CLNM. Because of the identification of CLNM in the implementation of pCND, 15 (9.8%) of 153cN0 DTC patients were upgraded in TNM staging; all these patients were older than 45years. Fifty-six patients (36.6%) developed higher RRS (from low to intermediate) after pCND. For younger patients (age<45years), careful preoperative assessment of the lymph node status must be done; surgeons should consider this risk factor when deciding whether to perform pCND. Thorough lymphadenectomy in the implementation of pCND can avoid residual lymph node metastasis and help to increase the incidence of CLNM. pCND can indentify occult CLNM which allows more precise TNM staging (for patients with age≥45years) and RRS.

Impact of central node dissection on postoperative morbidity in pediatric patients with suspected or proven thyroid cancer

Pediatric risk factors for postoperative morbidity after central node dissection are ill-defined. This outcome study aimed to evaluate operative morbidity in patients aged ≤18years after total thyroidectomy with or without central node dissection for suspected or proven thyroid cancer. Included were 102 patients with hereditary C-cell hyperplasia, 66 patients with medullary, 60 patients with papillary, and 2 patients with follicular thyroid cancer. In all 230 patients, 131 of whom underwent central node dissection, transient recurrent laryngeal nerve palsy was significantly associated only with central node dissection (100% vs 55%; P=.010). Transient and permanent hypoparathyroidism were significantly associated with age (means of 11.9years versus 7.8years, and 12.9years versus 8.5years; P≤.002); central node dissection (80% vs 50%, and 100% vs 54%; P≤.001); and the number of central lymph nodes cleared (means of 12.2 nodes versus 5.4 nodes, and 26.9 nodes versus 5.8 nodes, P<.001). These effects were stronger for permanent than transient hypoparathyroidism. Correlations between permanent hypoparathyroidism and the number of nodes cleared on central node dissection (r=0.35) were closer than those between permanent hypoparathyroidism and age (r=0.15), but similar for transient hypoparathyroidism (r=0.22 and r=0.25). Owing to the incremental morbidity from central node dissection, the extent of a neck operation, in experienced hands, should be tailored to the extent of the underlying disease regardless of the child's age. The notion that the experience of the center and surgeons may be more important than the age of the child requires validation in independent series across different health care settings.

The Number of Lymph Nodes and Relationship with Presence of Thyroiditis and Thymic Tissue in the Central Neck Dissection Materials for Thyroid Papillary Carcinoma: Pathologic Analysis

Background: Central lymph node dissection (CLND) for papillary thyroid carcinoma (PTC) allows correct pathologic staging of lymph nodes and planning of postoperative management. The purpose of this study was to determine the number of the lymph nodes in the CLND and the relationship to presence of chronic lymphocytic thyroiditis (CLT) and thymic tissue (TT). Methods: Total thyroidectomy and CLND materials from 153 patients with PTC were included in this study. Two histopathologic features (presence of CLT and TT) were evaluated for their value in adequacy of CLND. Results: Histopathologic examination revealed CLT and TT in CLND materials in 70 (46%) and 63 (41%) patients, respectively. Total number of lymph nodes in CLND materials was significantly higher in CLT (+) and TT (+) groups (p Conclusions: Our study demonstrates that presence of CLT in thyroid gland has been associated with higher number of central lymph nodes mainly due to increased number of benign hyperplastic lymph nodes. It may be possible to conclude that upper limit of lymph nodes for satisfactory CLND would be higher to correctly evaluate central lymph node status in existing staging systems if specimens have CLT. Results of this study also show that the presence of TT in surgical materials may represent the adequacy of CLND.

Robotic versus Open Thyroidectomy for Differentiated Thyroid Cancer: An Evidence-Based Review.

While open thyroidectomy (OT) is advocated as the gold standard treatment for differentiated thyroid cancer, the contemporary use of robotic thyroidectomy (RT) is often controversial. Although RT combines the unique benefits of the surgical robot and remote access thyroidectomy, its applicability on cancer patients is challenged by the questionable oncological benefits and safety. This review aims to analyze the current literature evidence in comparing RT to OT on thyroid cancers for their perioperative and oncological outcomes. To date, no randomized controlled trial is available in comparing RT to OT. All published studies are nonrandomized or retrospective comparisons. Current data suggests that RT compares less favorably than OT for longer operative time, higher cost, and possibly inferior oncological control with lower number of central lymph nodes retrieved. In terms of morbidity, quality of life outcomes, and short-term recurrence rates, RT and OT are comparable. While conventional OT continues to be appropriate for most thyroid cancers, RT should better be continued by expert surgeons on selected patients who have low-risk thyroid cancers and have high expectations on cosmetic outcomes. Future research should embark on prospective randomized studies for unbiased comparisons. Long-term follow-up studies are also needed to evaluate outcomes on recurrence and survival.

A systematic review and meta-analysis evaluating completeness and outcomes of robotic thyroidectomy.

Despite immense interest, robotic-assisted thyroidectomy (RT) remains controversial in differentiated thyroid carcinoma (DTC). This systematic review and meta-analysis compared surgical completeness and/or oncological outcomes between RT and open thyroidectomy (OT) in low-risk DTC. Systematic review. A systematic review was performed to identify studies that compared surgical completeness and/or oncological outcomes between RT and OT in DTC. Any study that compared at least one parameter relating to surgical completeness and/or oncological outcome for DTC was considered. Number of central lymph nodes (CLNs) retrieved during central neck dissection (CND), preablation stimulated thyroglobulin (sTg) level, radioiodine uptake on post-therapy scan, and locoregional recurrence (LRR) were examined. Meta-analysis was performed using a fixed or random-effects model depending on heterogeneity between studies. Ten studies were eligible. Of the 2,205 DTCs, 752 (34.1%) had RT, whereas 1,453 (65.9%) had OT. Relative to OT, RT had significantly fewer CLNs retrieved during CND (4.7 ± 3.2 vs. 5.5 ± 3.8, standardized mean difference [SMD] = -0.240, 95% confidence interval [CI]: -0.364 to -0.116, P < .001) and higher preablation sTg level (3.6 ± 6.7 ng/mL vs. 2.0 ± 5.0 ng/mL, SMD = 0.272, 95% CI: 0.022 to 0.522, P = .033). Interestingly, these differences were more evident in the robotic transaxillary approach (RTAA) than the robotic bilateral axillo-breast approach. After a mean follow-up of 17.7 months, no LRR was found in RT, whereas after 18.6 months, one LRR was found in OT. Relative to OT, total thyroidectomy by RTAA was associated with fewer CLNs retrieved and less-complete thyroid resection. However, using RTAA is unlikely to compromise the outcomes of low-risk DTC because of its inherently good prognosis.

A systematic review and meta-analysis comparing outcomes between robotic-assisted thyroidectomy and non-robotic endoscopic thyroidectomy

BackgroundDespite its feasibility, using the da Vinci robot in remote-access thyroidectomy remains controversial. This meta-analysis compared surgical and oncological outcomes between robotic-assisted thyroidectomy (RT) and non-robotic endoscopic thyroidectomy (ET). MethodsA systematic review was performed to identify studies comparing outcomes between RT and ET. Outcomes included operating time, drain output, complications, number of central lymph nodes retrieved, and preablation stimulated thyroglobulin level. A random-effects model was used. ResultsSix studies were eligible. Of the 3510 patients, 2167 (61.7%) underwent RT whereas 1343 (38.3%) underwent ET. Despite a higher drain output (185.8 mLs versus 173.3 mLs, P = 0.019), RT had fewer temporary recurrent laryngeal nerve injury (2.6% versus 3.3%, P = 0.035) and shorter length of hospital stay (3.4 d versus 3.5 d, P = 0.030). In terms of oncological outcomes, despite higher incidence of multicentricity and larger tumors, the number of central lymph nodes retrieved during unilateral central neck dissection in RT was significantly greater than ET (4.5 ± 2.6 and 3.4 ± 2.5, P < 0.001) whereas the preablation stimulated thyroglobulin was comparable (0.8 ng/mL versus 1.1 ng/mL, P = 0.456). However, follow-up data were relatively scarce. ConclusionsAdding the robot in remote-access thyroidectomy was associated with a significantly lower risk of temporary recurrent laryngeal nerve injury and shorter length of hospital stay. However, despite achieving a comparable level of surgical completeness for low-risk differentiated thyroid carcinoma between RT and ET, this study highlighted the limitations with the current literature and the need for more prospective studies with adequate follow-up.

Negative Prognostic Implication of Fibrotic Pattern in Papillary Thyroid Cancer

Objectives: Lymph node metastasis in papillary thyroid cancer occurs 40-60% of the time. Extrathyroidal extension and large tumor size are the most reliable predicting factors for central lymph node metastasis whose prognostic value is controversial. In this study, we evaluated the relationship between a specific finding of primary tumor in the thyroid, fibrosis, and negative prognostic factors. Methods: We reviewed patients who underwent total thyroidectomy and central lymph node dissection with or without lateral lymph node dissection for papillary thyroid cancer (PTC), from January to December, 2011. We defined (+) finding when the degree of fibrosis comprised 10% or more of the primary tumor. Correlation between degree of fibrosis and negative prognostic factors, including age, gender, tumor size, extrathyroidal extension (ETE), number of central lymph node (CLN) metastases, and lateral cervical lymph node metastasis (LCLNM), was analyzed. Results: Of the 481 patients, fibrosis (+) group included 387 patients (80.5%). On the chi-square test, age, gender, tumor size, and LCLNM were not correlated with fibrosis. ETE (+) group comprised of higher rate of fibrosis (+) group (90.4%) compared to ETE (-) group (64.9%, P &lt; 0.001). CLN metastasis (+) comprised of higher rate of fibrosis (+) group (84.6%) compared to CLN metastasis (-) group (76.5%, P = 0.017). On the multivariate analysis, ETE was a significant risk factor of fibrosis (odds ratio = 2.545, P &lt; 0.001, confidence interval from 1.775 to 3.649). Conclusions: Fibrosis in PTC can be a risk factor of extrathyroidal extension, a negative prognostic factor. This suggests that the behavior of fibrotic tumor is, possibly, more aggressive than non-fibrotic tumor.

Effects of leaders and social power on opinion formation in complex networks

Social networks are inevitable parts of daily life and there has been an increasing interest in analyzing social phenomena on networked structures. Evolution of opinion formation is one of the topics that has attracted many scholars in the field. In this work we consider the influence of leaders and social power in the evolution of opinion formation. A number of central nodes with specific properties (e.g. nodes with highest degree, betweenness or vulnerability values) are taken as leaders whose opinions are kept unchanged, that is, not influenced by other agents. The leaders try to coordinate the opinions of other agents where the connection structure is considered to be preferential attachment scale-free, Watts–Strogatz small-world or Erdős–Rényi random networks. Numerical simulations show that scale-free networks provide faster consensus compared with other networks. We also study the effects of social power on the consensus time. The social power of a node is considered to be a function of its centrality. Having leaders in the network, we show that the consensus time could be significantly decreased by introducing social power. For scale-free networks, there is an optimal degree of social power in which the consensus time is minimal. These results show the appropriateness of scale-free topology in hierarchal organizations where leaders posit influence on peripheral agents.

Laparoscopic complete mesocolic excision (CME) with medial access for right-hemi colon cancer: feasibility and technical strategies

This study was designed to investigate the feasibility and technical strategies of laparoscopic complete mesocolic excision (CME) for right-hemi colon cancer. The clinical and pathological findings of 64 patients with right-hemi colon cancer who underwent laparoscopic CME between March 2010 and September 2011 were collected retrospectively. Among them, 35 cases were eligible for the final analysis through various screening factors. The quality of surgery also was assessed by reviewing the recorded video obtained through the operations in terms of specimen anatomic planes and completeness of the excised mesocolon. Laparoscopic CME is focused on applying the concept of enveloped visceral and parietal planes during the operations. Laparoscopic approach proceeds with medial access where the dissection starts at ileocolic vessel before proceeds along with the superior mesenteric vessel. The access also emphasized en bloc resection of mesocolon without defections to the planes. Besides, lymph node resections at the root of ileocolic; right colic and middle colic vessels are necessary for ileocecum cancer. Cancers at the hepatic flexure requires further dissection of subpyloric lymph nodes and of greater omentum that is within 15cm of the tumor and along the greater curvature. Thirty-five cases were evaluated as good plane. The median total number of central lymph nodes retrieved was 19 (range, 15-25) and central lymph node metastasis was found in 5 of all stage III cases. The median operation time was 2.6h and the blood loss was 80mL. The median time for passage of flatus and hospitalization were 2 and 12days respectively. Complications were observed in three cases. CME is a novel concept for colon cancer surgery and might be a standard for the procedure. Laparoscopic CME with medial access is technically feasible and randomized trials are needed to evaluate its long-term outcomes.

A note on radially Moore digraphs

Let D be a regular digraph with radius s. Then D is a radially Moore digraph if it has the maximum possible number of nodes and the diameter of D does not exceed s+1. We show that for each s and t there exists a regular radially Moors digraph of degree t with radius s. Moreover, we give an upper bound for the number of central nodes in radially Moore digraphs with degree two.