Risk factors and nomogram to predict skip metastasis in papillary thyroid carcinoma

Background

Papillary thyroid carcinoma (PTC) is the most common endocrine malignancy. Skip metastases of PTCs are easily misdiagnosed before surgery, and it could lead to re-operation and affect the prognosis. Although there are a few studies about nomograms for predicting central lymph node metastases (CLNM) or lateral lymph node metastases (LLNM) of PTCs, there are few studies about nomograms for skip metastases. Based on the clinical and ultrasonographic characteristics of patients with PTCs, the aim of our study was to investigate the risk factors and establish a nomogram for predicting the risk of skip metastases in PTCs.

Methods

This study enrolled 218 PTCs patients with lateral cervical lymph node metastases and their data were analyzed retrospectively. According to the postoperative pathological results, the patients were divided into skip-positive group and skip-negative group. In order to establish the nomogram, univariate and multivariate analyses were used to estimate risk factors of skip metastases. The receiver operating characteristic (ROC) curve, internal calibration plot and decision curve analysis (DCA) were used to evaluate the nomogram model's efficacy.

Results

There were statistical differences between skip-positive group and skip-negative group in tumor location, the maximum diameter (D) and capsule invasion (P<0.05). No statistical differences were observed in sex, age, Hashimoto's thyroiditis, multifocality, anteroposterior diameter/transverse diameter (A/T) ratio, shape, margin, microcalcification, intra-nodular vascularity and preoperative serum thyroglobulin (Tg) (P≥0.05). The risk factors of skip metastases in PTCs were D ≤10 mm, location in the upper portion and capsule invasion. The area under the curve (AUC) of nomogram was 0.877, the accuracy was 85.32%, the sensitivity was 60.98%, and the specificity was 90.96%. The calibration curve and the Hosmer-Lemeshow goodness of fit test showed that the consistency between the nomogram and the actual observation was good. The DCA showed that most PTC patients might benefit from the predictive nomogram model.

Conclusions

A nomogram for predicting skip metastases in PTCs may be useful in clinical diagnosis and treatment.

Combining Clinicopathologic and Ultrasonic Features for Predicting Skip Metastasis of Lateral Lymph Nodes in Papillary Thyroid Carcinoma

Background

Skip metastasis, regarded as lateral lymph node metastasis (LLNM) without involving the central lymph node metastasis (CLNM), in papillary thyroid carcinoma (PTC) patients is commonly unpredictable. The purpose of the present research was to investigate the independent risk factors of skip metastasis in patients with PTC.

Methods and Materials

In the present research, 228 consecutive PTC patients who experienced total thyroidectomy coupled with central and lateral lymph node dissection from May 2020 to September 2022 at the Affiliated hospital of Jiangsu University were included in our research. Univariate and multivariate analysis were then applied to investigate the risk factors of skip metastasis in patients with PTC. Furthermore, a predictive model of skip metastasis was then constructed based on risk factors.

Results

The skip metastasis rate was 11.8% (27/228) in the current research. After the univariate and multivariate analysis, tumor size ≤ 10 mm, unilaterality, microcalcification, and upper tumor location were determined to be predictive factors of skip metastasis. The risk score of skip metastasis was calculated: risk score = 1.229 × (if tumor nodule ≤ 10mm) + 1.518 × (if unilaterality nodule) + 1.074 × (if microcalcification in nodule) + 2.332 × (if nodule in upper location).

Conclusion

Tumor size ≤ 10 mm, unilaterality, microcalcification, and upper tumor location can increase the occurrence of skip metastasis in patients with PTC, which is expected to provide useful information to guide the suitable intraoperative window.

Degenerative Changes in Aging Human Pelvic Lymph Nodes-A Reason to Rethink Staging and Therapy of Regional Malignancies?

Lymph node metastases are common in pelvic urological tumors, and the age-related remodeling process of the pelvic lymph nodes influences metastatic behavior. The aim of this work is to characterize age-related degenerative changes in the pelvic lymph nodes with respect to their occurrence and extent. A total of 5173 pelvic lymph nodes of 390 patients aged 44 to 79 years (median 68 years, IQR 62-71 years) were histologically examined for degenerative structural changes. Lymph node size, lipomatous atrophy, capsular fibrosis, framework fibrosis, and calcifications were recorded semi-quantitatively and evaluated by age group. Significantly more lymph nodes <10 mm were found in older patients (p = 0.001). The incidence of framework fibrosis, capsular fibrosis, and calcifications increased significantly with increasing patient age (p < 0.001). In lipomatous atrophy, an increase in mild to moderate lipomatous atrophy was observed with increasing age (p < 0.001). In this, the largest study to date on this topic, age-related degenerative changes in pelvic lymph nodes were proven. Due to the consecutive decrease in hte filtration function of pelvic lymph nodes with increasing age, staging and therapy of metastatic pelvic urologic carcinomas should be reconsidered.

Predicting skip metastasis in lateral lymph nodes of papillary thyroid carcinoma based on clinical and ultrasound features

Background

Skip metastasis in papillary thyroid cancer (PTC), defined as lateral lymph node metastasis (LLNM) without the involvement of central lymph node metastasis (CLNM), is generally unpredictable. Our study aimed to develop a model to predict skip metastasis by using clinicopathological and ultrasound factors of PTC.

Methods

We retrospectively reviewed the medical records of patients who underwent total thyroidectomy and central lymph node dissection (CLND) plus lateral lymph node dissection (LLND) between January 2019 and December 2021 at the First Affiliated Hospital of Soochow University. Furthermore, univariate and multivariate analyses assessed the clinical and ultrasound risk factors. Receiver operating characteristic (ROC) curves were used to find the optimal cut-off values for age and dominant nodule diameter. Multivariate logistic regression analysis results were used to construct a nomogram and were validated internally.

Results

In all patients, the skip metastasis rate was 15.4% (41/267). Skip metastasis was more frequently found in patients with a tumour size ≤10 mm (OR 0.439; P = 0.033), upper tumour location (OR 3.050; P=0.006) and fewer CLNDs (OR 0.870; P = 0.005). After analysing the clinical and ultrasound characteristics of the tumour, five factors were ultimately associated with lateral lymph node skip metastasis and were used to construct the model. These factors were an age >40 years, tumour diameter <9.1 mm, upper tumour location, non-smooth margin and extrathyroidal extension. The internally evaluated calibration curves indicated an excellent correlation between the projected and actual skip metastasis probability. The nomogram performed well in discrimination, with a concordance index of 0.797 (95% CI, 0.726 to 0.867).

Conclusions

This study screened for predictors of skip metastasis in PTC and established a nomogram that effectively predicted the risk of potential skip metastasis in patients preoperatively. The method can predict and distinguish skip metastases in PTC in a simple and inexpensive manner, and it may have future therapeutic utility.

The proposed modification of TNM staging and therapeutic strategy for skip metastasis in papillary thyroid carcinoma: A multicenter retrospective cohort study

BACKGROUND

Skip metastasis is a special type of lateral lymph node metastasis, which is not classified definitely by the eighth edition of the AJCC TNM staging system. The aim of the research was to study the prognosis of skip metastasis in PTC patients, and carry out a more appropriate N staging for skip metastasis.

METHODS

Study subjects were 3167 patients with papillary thyroid carcinoma (PTC), who underwent thyroidectomy at three clinical centers from 2016 to 2019. We identified two well-balanced cohorts matched on the basis of propensity score.

RESULTS

During a median follow-up of 42 months, recurrence occurred in 68 (4.3%) patients with lymph node metastasis. 34 cases recurred in 1120 patients with central lymph node metastasis (N1a), and 34 recurred in 461 patients with lateral lymph node metastasis (N1b), among which 73 patients were diagnosis with skip metastasis. The RFS of N1a was significantly lower than that of N1b (p < 0.001). After propensity-score matching, recurrence rate was significantly lower in the skip metastasis group than in the LLNM group (p = 0.039), whereas the rate was similar in the skip metastasis groups and the CLNM group (p = 0.29).

CONCLUSIONS

In conclusion, our study indicated that, among patients with LLNM, those with positive skip metastasis showed significantly lower recurrence, exhibiting a similar rucurrence tendency as patients with CLNM. Thus, skip metastasis could be categorized into N1a stage rather than N1b stage based on the AJCC TNM staging system. The downstaging of skip metastasis may reveal more conservative treatment strategy.

Patterns of Neck Nodal Metastasis from Oral Cavity Carcinoma

Nitin KhuntetaObjectives  The aim is to study the patterns of lymph node metastasis from various sites in oral cavity cancer and determine the risk factors for metastasis. Materials and Methods  It is a prospective observational study. The inclusion criteria were-245 patients of carcinoma buccal mucosa, anterior two-thirds of tongue, hard palate, oral surface of soft palate, floor of mouth, vestibule, and alveolus. The exclusion criteria were-patients who had received preoperative chemotherapy or radiotherapy and patients with recurrent disease. Statistical Methods  All data were analyzed using SPSS 18.0 and Graphpad prism 7 software for statistical analysis. Count data have been expressed as percentages (%). The χ ² test was used for univariate analysis of the risk factors of cervical lymph node metastasis. The odds ratio value (with 95% confidence interval) was used to express the risk of cervical lymph node metastasis. p -Value of <0.05 was considered as the difference with statistical significance. Results  The most common site involved was buccal mucosa. Patterned lymph node metastasis was seen in 93.5% cases. Skip metastasis was seen in 4.31% cases. Level I b was the most common site of nodal involvement for all primary subsites of oral cavity cancer. The incidence of positive nodes on histopathological analysis was highest in cases of lower alveolus (63.15%), followed by tongue. Conclusion  In our study, patterns of lymph node metastasis for oral cavity cancer were comparable to other studies with large number of subjects. The incidence of skip metastasis or aberrant status was low. On multivariate analysis, depth of invasion of tumor, pathologic grade, pathologic T stage, and morphologic type of growth were found to be independent predictors of risk for metastasis.

The Prognosis of Skip Metastasis in Papillary Thyroid Microcarcinoma Is Better Than That of Continuous Metastasis

CONTEXT

A few papillary thyroid microcarcinomas (PTMCs) may have skip metastasis (SLNM), but the risk factors remain controversial and the prognosis is unclear.

OBJECTIVES

To investigate the incidence, lymph node metastasis (LNM) patterns, risk factors, and prognosis of SLNM in PTMCs.

METHODS

We reviewed the medical records of PTMC patients who underwent thyroid surgery in our institution. Analyses of risk factors were performed for SLNM. Recurrence-free survival (RFS) of SLNM, central lymph node metastasis (CLNM), and continuous metastasis (CLNM and lateral lymph node metastasis [CLNM + LLNM]) were compared after propensity score matching (PSM).

RESULTS

SLNM was detected in 1.7% (50/3923) and frequently involved level III (66.7%). Compared with CLNM + LLNM, SLNM had more LNM at a single level (P < 0.01) and less LNM at 2 levels (P < 0.05). A tumor size of 0.5 to 1 cm (odds ratio [OR], 2.26; 95% CI, 1.27-4.00) and location in the upper pole (OR, 3.30; 95% CI, 2.02-5.40) were independent risk factors for SLNM. A total of 910 (23.2%) PTMCs with LNM were included in the prognostic analysis. At a median follow-up of 60 months, the RFS of SLNM did not differ from that of CLNM (P = 0.10) but was significantly higher than that of CLNM + LLNM (P < 0.01) after using PSM.

CONCLUSIONS

When the tumor size is 0.5 to 1 cm or its location is in the upper pole, we must remain vigilant to SLNM in PTMC. Because its prognosis is comparable to that of only CLNM and better than that of CLNM + LLNM, less intensive treatment should be considered.

Surgeon-Pathologist Team Approach Dramatically Affects Lymph Nodes Detection and Improves Patients' Short-Term Outcome

Simple Summary

Appropriate lymph node harvesting for patients with gastric cancer is fundamental for a correct staging and is strongly related to survival. In this study, we present a new protocol for on-site macroscopic evaluation and sampling of lymph nodes for gastric cancer patients. With the joint collaboration of surgeons and pathologists, our method aims to provide the largest possible number of analyzed lymph nodes per patient, allowing for a better staging. We are convinced that this approach is routinely feasible, and our preliminary results seem to confirm better patient stratification compared to other lymph node dissection methods.

Abstract

The downstaging of gastric cancer has recently gained particular attention in the field of gastric cancer surgery. The phenomenon is mainly due to an inappropriate sampling of lymph nodes during standard lymphadenectomy. Hence, collection of the maximum number of lymph nodes is a critical factor affecting the outcome of patients. None of the techniques proposed so far have demonstrated a real efficiency in increasing the number of identified lymph nodes. To harvest the maximum number of lymph nodes, we designed a protocol for on-site macroscopic evaluation and sampling of lymph nodes according to the Japanese Gastric Cancer Association protocol. The procedure was carried out by a surgeon/pathologist team in the operating room. We enrolled one hundred patients, 50 of whom belonged to the study group and 50 to a control group. The study group included patients who underwent lymph node dissection following the proposed protocol; the control group encompassed patients undergoing standard procedures for sampling. We compared the number and maximum diameter of lymph nodes collected in both groups, as well as some postoperative variables, the 30-day mortality and the overall survival. In the study group, the mean number of lymph nodes harvested was higher than the control one (p = 0.001). Moreover, by applying the proposed technique, we sampled lymph nodes with a very small diameter, some of which were metastatic. Noticeably, no difference in terms of postoperative course was identified between the two groups, again supporting the feasibility of an extended lymphadenectomy. By comparing the prognosis of patients, a better overall survival (p = 0.03) was detected in the study group; however, to date, no long-term follow-up is available. Interestingly, patients with metastasis in node stations number 8, 9, 11 or with skip metastasis, experienced a worse outcome and died. Based on our preliminary results, the pathologist/surgeon team approach seems to be a reliable option, despite of a slight increase in sfaff workload and technical cost. It allows for the harvesting of a larger number of lymph nodes and improves the outcome of the patients thanks to more precise staging and therapy. Nevertheless, since a higher number of patients are necessary to confirm our findings and assess the impact of this technique on oncological outcome, our study could serve as a proof-of-concept for a larger, multicentric collaboration.

Trans-lymphatic contrast-enhanced ultrasound with sentinel lymph node biopsy for detecting cervical skip metastasis to lymph nodes in early-stage oral tongue squamous cell carcinoma

OBJECTIVES

The purpose of this study was to assess whether trans-lymphatic contrast-enhanced ultrasound (CEUS) combined with sentinel lymph node biopsy can be used to assess the status of cervical lymph nodes and skip metastasis in patients with early squamous cell carcinoma (SCC) of the oral tongue.

METHODS

This study included 21 subjects with early oral tongue SCC who received multiple intramucosal peritumoral injections of Sonazoid. CEUS examinations were performed immediately after Sonazoid injection to identify sentinel lymph nodes (SLNs). The SLNs were excised for histological examination to determine if the lymph nodes has metastases.

RESULTS

Thirty-five SLNs were detected by CEUS after Sonazoid injection in the subjects. SLNs were identified in 20 of the total 21 subjects. Four participants had metastasis to lymph nodes, and one had skip metastasis in level Ⅲ. In one subject, SLNs were successfully detected in level Ⅳ without skip metastasis.

CONCLUSIONS

Trans-lymphatic CEUS combined with sentinel lymph node biopsy showed high accuracy for evaluating cervical lymph node status. This could be a reliable approach for detecting cervical skip metastases of lymph nodes in early-stage oral cancer patients.

Toluidine blue for the detection of sentinel lymph nodes in patients with thyroid cancer

Introduction

Thyroid cancer (TC) demonstrates steady growth in incidence worldwide and remains an urgent problem in oncology. The detection of sentinel lymph nodes (SLN) with a selective dye and further histological examination in selecting the proper (personalized) surgical strategy and the volume of surgical intervention for clinically undetermined regional lymph nodes. The purpose of the study is to evaluate the effectiveness and safety of intraoperative detection of SLN with a 1% toluidine blue aqueous solution.

Material and methods

The significant tasks are to identify the pattern of TC metastases to cervical lymph nodes, to establish the prevalence of "skip" metastases, to compare the frequency of complications after total thyroidectomy and central neck dissection and lateral neck dissection with total thyroidectomy and central neck dissection, and to determine the feasibility of the application of lateral neck dissections in patients with papillary and follicular TC without metastases to regional lymph nodes (according to physical examination and ultrasound).

Results

According to our data the SLN identification rate was 97.6%. Sensitivity, specificity, positive predictive value, negative predictive value, and frequency of false negative and false positive results was 89.2, 94.6, 88.03, 95.16, 10.8, and 5.4%, respectively. The most common metastasis was in the central neck compartment (83.7%). Skip metastases were determined in 4.9% of patients.

Conclusions

The low prevalence of "skip" metastases and a significant risk of postoperative complications (wound exudation, lymphorrhagia, inflammation, hypoparathyroidism, paresis of the vocal cords) support the idea that lateral neck dissection is appropriate only in cases of confirmed metastases by physical examination and/or ultrasound at the preoperative stage.

Predictors of Central Compartment Involvement in Patients with Positive Lateral Cervical Lymph Nodes According to Clinical and/or Ultrasound Evaluation

Lymph node neck metastases are frequent in papillary thyroid carcinoma (PTC). Current guidelines state, on a weak level of evidence, that level VI dissection is mandatory in the presence of latero-cervical metastases. The aim of our study is to evaluate predictive factors for the absence of level VI involvement despite the presence of metastases to the lateral cervical stations in PTC. Eighty-eight patients operated for PTC with level II–V metastases were retrospectively enrolled in the study. Demographics, thyroid function, autoimmunity, nodule size and site, cancer variant, multifocality, Bethesda and EU-TIRADS, number of central and lateral lymph nodes removed, number of positive lymph nodes and outcome were recorded. At univariate analysis, PTC location and number of positive lateral lymph nodes were risk criteria for failure to cure. ROC curves demonstrated the association of the number of positive lateral lymph nodes and failure to cure. On multivariate analysis, the protective factors were PTC located in lobe center and number of positive lateral lymph nodes < 4. Kaplan–Meier curves confirmed the absence of central lymph nodes as a positive prognostic factor. In the selected cases, Central Neck Dissection (CND) could be avoided even in the presence of positive Lateralcervical Lymph Nodes (LLN+).

The Significance of Skip Mediastinal Lymph Node Metastasis in the Prognosis of Patients with Resected Non-Small-Cell Lung Carcinoma: Is It Really a Better N2 Disease Subtype?

Objective: In this study, we aimed to reveal the prognostic differences between skip and non-skip metastasis mediastinal lymph node (MLN) metastasis.

Methods: A total of 202 patients (179 males and 23 females; mean age, 59.66 ± 9.89 years; range: 29–84 years) who had ipsilateral single-station MLN metastasis were analyzed in two groups retrospectively between January 2009 and December 2017: “skip ipsilateral MLN metastasis” group (sN2) (n = 55,27.3%) [N1(–), N2(+)], “non-skip ipsilateral MLN metastasis” group (nsN2) (n = 147,72.7%) [N1(+), N2(+)].

Results: The mean follow-up was 42.63 ± 34.91 months (range: 2–117 months). Among all patients, and in the sN2 and nsN2 groups, the median overall survival times were 63.5 ± 4.56, 68.8 ± 7, and 59.3 ± 5.35 months, respectively, and the 5-year overall survival rates were 38.2%, 46.3%, and 36.4%.

Conclusion: Skip metastasis did not take its rightful place in TNM classification; thus, further studies will be performed. To detect micrometastasis, future studies on skip metastasis should examine non-metastatic hilar lymph nodes (LNs) through staining methods so that heterogeneity in patient groups can be avoided, that is, to ensure that only true skip metastasis cases are included. Afterwards, more accurate and elucidative studies on skip metastasis can be achieved to propound its prognostic importance in the group of N2 disease.

Skip metastasis in mediastinal lymph node is a favorable prognostic factor in N2 lung cancer patients: a meta-analysis

Background

Skip metastasis is a common lymph node metastatic pattern in non-small cell lung cancer (NSCLC). The relationship between skip metastasis and specific clinicopathologic factors and the prognostic value of skip metastasis are controversial.

Methods

A systematic search and analysis of skip metastasis in NSCLC was conducted in the databases of PubMed, EMBASE, and Web of Science up to Dec 2019. Summarized hazard ratio (HR), mean difference (MD), and odds ratio (OR) with associated 95% confidence intervals (CI) were evaluated to investigating the relationship between skip metastasis and overall survival (OS), disease-free survival (DFS), recurrence-free survival (RFS) and clinicopathological features in NSCLC.

Results

29 studies with a total of 1,806 skip and 4,670 non-skip N2 patients were included. The upper lobe tumor showed a higher rate of skip metastasis compared with lower lobe one (RR =1.16, 95% CI: 1.00–1.34, P=0.044, I²=39.8%). The presence of skip metastasis correlated with superior overall survival (HR =0.74, 95% CI: 0.66–0.83, P<0.001, I²=48.2%) and DFS or RFS (HR =0.71, 95% CI: 0.61–0.84, P<0.001, I²=18.2%). Further subgroup analyses indicated similar results in articles that reported intrapulmonary lymph node dissection (HR =0.67, 95% CI: 0.57–0.77, P<0.001, I²=0).

Conclusions

The results indicate that the presence of skip metastasis is associated with a marked increase in survival of NSCLC patients compared to patients with non-skip N2 metastasis. These results suggest that skip metastasis might be a distinct subgroup for purposes of N staging of NSCLC patients, and intrapulmonary lymph node assessment is needed.

A Specific Predicting Model for Screening Skip Metastasis From Patients With Negative Central Lymph Nodes Metastasis in Papillary Thyroid Cancer

Skip metastasis is a specific type of papillary thyroid cancer lymph node metastasis (LNM). The present study aimed to clarify the typical clinical characteristics of skip metastasis and optimize the prediction model, so as to provide a more individual treatment mode for skip metastasis. We retrospectively analyzed 1075 PTC patients with different lymph node metastasis statuses from two clinical centers. Comparisons have been made between patients with skip metastasis and other types of LNM. Univariate and multivariate analyses were performed to detect the risk factors for skip metastasis with negative LNM, and a nomogram for predicting skip metastasis was established. The rate of skip metastasis was 3.4% (37/1075). Compared with other types of LNM, significant differences showed in tumor size, upper portion location, thyroid capsular invasion, and ipsilateral nodular goiter with the central lymph node metastasis (CLNM) group, and in age and gender with the lateral lymph node metastasis (LLNM) group. Four variables were found to be significantly associated with skip metastasis and were used to construct the model: thyroid capsular invasion, multifocality, tumor size > 1 cm, and upper portion. The nomogram had good discrimination with a concordance index of 0.886 (95% confidence interval [CI], 0.823 to 0.948). In conclusion, the significant differences between skip metastasis and other types of LNM indicated that the lymph node drainage pathway of skip metastasis is different from either CLNM or LLNM. Furthermore, we established a nomogram for predicting risk of skip metastasis, which was able to effectively predict the potential risk of skip metastasis in patients without preoperative LNM clue.

Metastatic Patterns of Mediastinal Lymph Nodes in Small-Size Non-small Cell Lung Cancer (T1b)

Background: Lymph node metastasis (LNM) status is critical to the treatment. Fewer studies has focused on LNM in patients with small-size non-small cell lung cancer (NSCLC). This study aims to investigate clinicopathological characteristics associated with skip N2 (SN2) and non-skip N2 (NSN2) metastasis, and their metastatic patterns in NSCLC with tumor size of 1–2 cm.

Methods: We reviewed the records of NSCLC patients with tumor size of 1–2 cm who underwent lobectomy with systematic lymph node dissection (LND) between January 2013 and June 2019. Clinical, radiographical, and pathological characteristics were compared among N1, SN2, and NSN2 groups. Metastatic patterns of mediastinal lymph node were analyzed based on final pathology.

Results: A total of 63 NSCLC patients with tumor size of 1–2 cm were staged as pN2, including 25 (39.7%) SN2 and 38 (60.3%) NSN2. The incidence rates of SN2 and NSN2 were 2.8% (25/884) and 4.3% (38/884), respectively. For all clinicopathological characteristics, no significant difference was observed among the groups of N1, SN2, and NSN2. For the tumor located in each lobe, specific nodal drainage stations were identified: 2R/4R for right upper lobe; 2R/4R and subcarinal node (#7) for right middle lobe and right lower lobe; 4L and subaortic node (#5) for left upper lobe; #7 for left lower lobe. However, there were still a few patients (10.9%, 5/46) had the involvement of lower zone for tumors of upper lobe and the involvement of upper zone for lower lobe.

Conclusions: SN2 occurs frequently in patients with small-size NSCLC. Whether lobe-specific selective LND is suitable for all small-size patients deserves more studies to confirm. Surgeons should be more careful when performing selective LND for tumors located in the lower and upper lobes.

Prevalence, Risk Factors And Location Of Skip Metastasis In Papillary Thyroid Carcinoma: A Systematic Review And Meta-Analysis

Background

Skip metastasis is a special type in cervical lymph node metastasis (LNM) of patients diagnosed with papillary thyroid carcinoma (PTC) which induced poor prognosis. There are few studies about skip metastasis and conclusions remained uncertain. Therefore, this study aims to explore the frequency and to investigate risk factors of skip metastasis in PTC.

Methods

Through searching the keyword by PubMed and Embase databases which articles published up to 1^st August 2018 about skip metastasis in papillary thyroid carcinoma, we extract data in order to assure whether those materials meet the criteria.

Results

The prevalence of skip metastasis is 12.02% in light of our meta-analysis of 18 studies with 2165 patients. The upper pole location (RR = 3.35, 95% CI =1.65-6.79, P = 0.0008) and tumors size ≤1 cm (RR = 2.65, 95% CI =1.50-4.70, P = 0.0008) are significantly associated with skip metastasis, whereas lymphovascular invasion (RR = 0.33, 95% CI =0.15-0.75, P = 0.0083) exists lower rate of skip metastasis. Multifocality, gender, age, bilaterality, thyroiditis and Extrathyroidal extension (ETE) are insignificantly associated with skip metastasis. Level II and level III are the most frequently affected areas.

Conclusion

The lateral compartment should be carefully examined especially for those PTC patients who present primary tumors in the upper lobe with a primary tumor size ≤10 mm which could be detected with skip metastasis.

Clinicopathological features of T1 colorectal carcinomas with skip lymphovascular invasion

With recent advances in endoscopic treatment, many T1 colorectal carcinomas (CRCs) are resected endoscopically with a negative margin. However, some lesions exhibit skip lymphovascular invasion (SLVI), which is defined as the discontinuous foci of the tumor cells within the colon wall. The aim of the present study was to reveal the clinicopathological features of T1 CRCs with SLVI and validate the Japanese guidelines regarding SLVI. A total of 741 patients with T1 CRCs that were resected surgically between April 2001 and October 2016 in our hospital were divided into two groups: With SLVI and without SLVI. Clinicopathological features compared between the two groups were patient's gender, age, tumor size, location, morphology, lymphovascular invasion, tumor differentiation, tumor budding and lymph node metastasis. The incidence of T1 CRCs with SLVI was 0.9% (7/741). All cases with SLVI were found in the sigmoid colon or rectum. T1 CRCs with SLVI showed significantly higher rates of lymphovascular invasion than those without SLVI (P<0.01). In conclusion, lymphovascular invasion was a significant risk factor for SLVI in T1 CRCs, and for which surgical colectomy was necessary. The Japanese guidelines are appropriate regarding SLVI. Registered in the University Hospital Medical Network Clinical Trials Registry (UMIN000027097).

Prognostic Significance of Solitary Lymphnode Metastasis and Micrometastasis in Gastric Cancer

Gastric cancer (GC) used to be one of the most common malignancies in the world and still is the second leading cause of malignancy-related death in the Far East. The most significant factors that were found to be associated with the clinical outcome in patients with non-metastatic (M₀) gastric cancer is tumor's depth of invasion, the presence and the extend of lymphnode involvement, as well as the histological type according to Lauren (intestinal or diffuse). Although it is generally accepted that D2 gastrectomy is the procedure of choice to achieve adequate oncologic excision, there are quite many concerns for its use in patients with early gastric cancer (EGC), where N_o or N₁ specimens are frequently reported. The last two decades, with the evolvement of cancer cell detection techniques, the attend of the medical community is focused on GC patients with solitary lymphnode metastasis (SLN) or micrometastasis (mM). There is a discussion whether SLN should be attributed as the “real” sentinel node (SN) and its projection on patients' survival. The aim of this study is to review the recent literature and attempt to clarify the clinical significance of SLN in gastric cancer.

Skip lateral lymph node metastasis leaping over the central neck compartment in papillary thyroid carcinoma

Objective

This study was performed to investigate the frequency and pattern as well as the predictive factors of skip metastasis (lateral cervical lymph node metastasis without central lymph node metastasis) in papillary thyroid carcinoma (PTC).

Methods

450 PTC patients who received total thyroidectomy with central neck dissection(CND) combined with modified radical lateral neck dissection(LND) were divided into two groups: with or without skip metastases. The clinicopathological characteristics were statistically compared and analyzed, and univariate and multivariate analyses were performed to detect the risk factors of skip metastasis.

Results

The skip metastasis rate was 8.7% (39/450), and patients with skip metastases had fewer lateral lymph node metastases but were more likely to have single-level lateral metastasis, which are considered Level II(P<0.05). Skip metastasis was significantly associated with the primary tumor location in the upper portion (OR=18.495, 95% CI 6.612-51.731), a primary tumor size ≤10mm (OR=32.492, 95% CI 11.973-88.174) and Capsule invasion (OR=5.822, 95% CI 1.954-17.343) as demonstrated by our prospective study of 10 patients who received an injection of 0.1 ml carbon nanoparticles under ultrasonography in the upper portion of the lobe: 7(70%) had lateral compartment lymph node black staining without ipsilateral center compartment lymph node staining. However, skip metastasis did not affect the PTC patients’ long-term tumor-free survival rate (P=0.432).

Conclusion

Skip metastases can be common, and the primary tumor location in the upper portion, a primary tumor size ≤10 mm, and capsular invasion are closely linked to skip metastasis. The lateral compartment should be carefully evaluated.

Prognostic impact of lymph node skip metastasis in Stage III colorectal cancer

AIM

The aim of this study was to evaluate the prognostic impact of lymph node skip metastasis (LNSM) in patients with Stage III colorectal cancer.

METHOD

Between April 2003 and December 2014, a total of 41 patients with lymph node skip metastasis (skip+) were compared with 86 patients with pericolic lymph node metastases [lymph node distribution (LND)1] and 57 patients with intermediate and/or main lymph node metastasis (LND2+3). All patients had radical D3 lymphadenectomy, performed either laparoscopically or as open surgery.

RESULTS

The frequency of pT1-2 stage cancer was significantly higher in the skip+ group than in the LND1 group (26.8% vs 5.8%, P = 0.001). The number of metastatic lymph nodes in the skip+ group was lower than in the LND2+3 group (1.9 ± 1.5 vs 6.5 ± 6.0, P < 0.001). The 3-year disease-free survival (DFS) of the skip+, LND1 and LND2+3 groups was 64.8%, 69.7% and 40.1%, respectively (P = 0.008). The 3-year systemic recurrence rates of the skip+, LND1 and LND2+3 groups were 30.2%, 20.3% and 48.1%, respectively; (P = 0.002). Cox regression analysis revealed that preoperative carcinoembryonic antigen (CEA) of ≥ 5 ng/ml [hazard ratio (HR) = 2.2, P = 0.029], poor differentiation (HR = 3.8, P = 0.001) and skip+ (HR = 0.2, P = 0.021) were independently prognostic factors for DFS.

CONCLUSION

The prognosis for the LND1-negative lymph node skip metastasis group was better than for the LND2+3 group and was comparable with that of the LND1 group after radical D3 lymphadenectomy.

A case of rectal carcinoid, 7 mm in diameter, with skip metastasis to the lateral lymph node

The present case study presented a 59-year-old man with a 7 mm submucosal tumor in the lower rectum and swelling in a 7 mm lateral lymph node (the obturator lymph node). No swelling of the lymph nodes within the mesorectum was observed. The patient underwent laparoscopic intersphincteric resection with left side lateral lymphadenectomy. At the pathological examination, the patient was diagnosed with a rectal neuroendocrine tumor (Grade 1; carcinoid), which had invaded the perirectal tissues and exhibited lateral lymph node metastasis; however, mesorectal lymph node metastasis was not observed, therefore, the definitive diagnosis was rectal carcinoid with skip metastasis to the lateral lymph node. No sign of recurrence was observed at the 3 year follow-up. The treatment algorithm of rectal carcinoid was decided by the risk of lymph node metastasis. The present study confirmed skip metastasis to the lateral lymph node from the rectal carcinoid, which is typically very slow growing and has a low grade malignant potential.

Analysis of factors influencing skip lymphatic metastasis in pN(2) non-small cell lung cancer

OBJECTIVE

Although many clinical studies on skip lymphatic metastasis in non-small cell lung cancer have been reported, the risk factors for skip lymphatic metastasis are still controversy and debatable. This study investigated, by multivariate logistic regression analysis, the clinical features of skip metastasis to mediastinal lymph nodes (N(2)) in non-small cell lung cancer (NSCLC) patients.

METHODS

We collected the clinicopathological data of 256 pN(2)-NSCLC patients who underwent lobectomy plus systemic lymph node dissection in Fujian Medical University Union Hospital. The cases in the present study were divided into two groups: skip metastasis (N(2) skip+) and non- skip metastasis (N(2) skip-). A retrospective analysis of clinical pathological features of two groups was performed. To determine an independent factor, multivariate logistic regression analysis was used to identify possible risk factors.

RESULTS

A total of 256 pN(2)-NSCLC patients were recruited. The analysis results showed that gender, pathologic types, surgery, pleural involvement, smoking history, age, tumor stages, and differentiation were not statistical significant factors impacting on skip metastasis in pN(2)-NSCLC (P>0.05), whereas tumor size was an independent factor for skip metastasis (P=0.02).

CONCLUSIONS

The rate of skip lymphatic metastasis increases in pN(2)-NSCLC patients, in accompany with an increased tumor size.