Pattern Of Lymph Node Metastasis Research Articles

A predictive model of lymph node metastasis for thymic epithelial tumours.

Thymic epithelial tumours (TETs) are relatively rare indolent malignancies in the mediastinum. Lymph node metastasis (LNM) is an important prognostic indicator for TETs; however, the pattern of LNM involved in TETs has yet to be elucidated. Patients diagnosed with histologically confirmed thymoma (A-B3), thymic carcinomas and thymic neuroendocrine tumours, between 1988 and 2016 were identified from the Surveillance, Epidemiology, and End Results database. Univariable and multivariable logistic regression analyses were applied to identify the predictors for LNM. The predictive nomogram was built from the independent risk factors and measured using the concordance statistic. The overall proportion of TETs with LNM was 18.5% (200/1048). The rate of LNM in thymoma, thymic carcinomas and thymic neuroendocrine tumours was 6.8% (42/622), 30.2% (100/331) and 61.1% (58/95), respectively. According to the logistic regression analysis, histology type and T stage were independent factors correlated with LNM. A predictive nomogram model was developed with a concordance statistic of 0.807 (95% confidence interval: 0.773-0.841), which was significantly better than the T stage (P < 0.001) while had limited benefit to the histology type (P = 0.047). The calibration curve for the nomogram comparing the predicted and actual probabilities after bias correction showed good agreement. Nodal involvement was not uncommon in TETs. Main factors related to LNM in TETs were histology type and T stage. The probability of LNM could be well calculated using the predictive model.

Patterns and influence of nodal metastases after neoadjuvant chemoradiation and R0 resection in esophageal adenocarcinoma

ObjectiveLittle is known about the pattern of nodal metastases in patients with esophageal adenocarcinoma who have received neoadjuvant chemoradiation and undergone surgery. We sought to assess this pattern and evaluate its association with prognosis. MethodsAll patients with esophageal adenocarcinoma who underwent neoadjuvant chemoradiation and R0 esophagectomy between 2010 and 2018 at our institution were included (n = 537). The primary objective was to evaluate the association of sites of lymph node metastases with disease-free survival. The number of nodal stations and individual sites of nodal metastases were evaluated first in univariable then in separate multivariable Cox regression models adjusted for clinical factors. ResultsOf 537 patients, 193 (36%) had pathologic nodal metastases at the time of surgery; 153 (28%) had single-station disease, 32 (6.0%) had 2-station disease, and 8 (1.5%) had 3-station disease. The majority of patients with multiple positive nodal stations had positive nodes in the paraesophageal (93%) and/or left gastric stations (60%). Multivariable models controlling for clinical factors showed that an increasing number of positive nodal stations (hazard ratio, 1.59; 95% CI, 1.35-1.84; P < .01)—in particular, the subcarinal (hazard ratio, 2.78; 95% CI, 1.54-5.03; P < .01) and paraesophageal stations (hazard ratio, 2.0; 95% CI, 1.58-2.54; P < .01)—was associated with increased risk of recurrence. ConclusionsOne-third of patients who have undergone R0 resection for esophageal adenocarcinoma following induction chemoradiation therapy have metastatic lymph nodes. An increasing number of nodal stations, particularly paraesophageal and subcarinal metastases, were associated with increased risk of recurrence.

Pattern of Cervical Lymph Node Metastasis in Squamous Cell Carcinoma of Buccal Mucosa and Its Correlation for Optimal Neck Management

Objective: To document cervical node metastasis in oral squamous cell carcinoma (OSCC) of buccal mucosa and analyze the oncological necessity of most suitable neck dissection, in population of a tertiary care hospital.&#x0D; Study Design: Descriptive cross-sectional study.&#x0D; Place and Duration of Study: Maxillofacial department, Abbasi Shaheed Hospital, Karachi Pakistan, from Jul 2018 to Jul 2020.&#x0D; Methodology: It was a study of 110 histopathologically proven patients of Oral Squamous Cell Carcinoma of buccal mucosa. Non-probability sampling technique was used and sample size was calculated with help of WHO software using 8% prevalence of cervical metastasis in oral squamous cell carcinoma of buccal mucosa, 95% confidence interval, 7% margin of error. Patients aged 18-75 years, either gender, resectable tumor with or without lymph node involvement were included. Patients treated previously, with distant metastasis, unfit for general anesthesia and not willing to give consent were excluded. Tumor resection with selective neck dissection was done by one experienced surgeon and specimens were sent to same laboratory for histopathology. Data was collected on a proforma and analyzed using SPSS version 26.&#x0D; Result: Out of 110 patients 93 (84.5%) were male and 17 (15.5%) were female. Mean age was 43 years ± 12.75. Occurrence of occult metastasis was 41.8%. According to histopathologically positive metastatic node, highest incidence was in level I 21 (19.1%) followed by levels I, II, III 12 (10.9%) and levels I-II 7 (6.4%), while positive levels I, II, III, IV were seen in only 2 (1.8%) cases.&#x0D; Conclusion: Oral Squamous Cell Carcinoma.............

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

A few papillary thyroid microcarcinomas (PTMCs) may have skip metastasis (SLNM), but the risk factors remain controversial and the prognosis is unclear. To investigate the incidence, lymph node metastasis (LNM) patterns, risk factors, and prognosis of SLNM in PTMCs. 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). 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. 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.

Incidence and outcomes of nodal metastasis in clinically nonmuscle-invasive bladder cancer.

577 Background: Radical cystectomy (RC) is recommended in NMIBC patients with high risk of progression or persistent disease despite intravesical therapy. The role and extent of lymphadenectomy is controversial and not universally performed in this population. The objective of this study is to evaluate the incidence and pattern of nodal metastasis in patients undergoing radical cystectomy for treatment of clinically non-muscle invasive bladder cancer. Methods: Prospectively collected data of patients who underwent RC and ‘super-extended’ LND with intent-to-cure for urothelial carcinoma of the bladder between 2002 and 2019 were examined. Inclusion criteria were(a) clinical stage Ta, Tis,or T1, (b) muscle present and not involved,(c) no prior diagnosis of T2 disease, (d) no prior neoadjuvant therapy, and (e) super-extended lymphadenectomy performed to level of IMA with mapping information available. Logistic regression analysis was used to evaluate for predictors of node metastasis. Results: A total of 223 patients met inclusion criteria with a median follow up of 8.2 years (IQR 4.1-10.7). Lymph node metastasis was identified in 8.1% (18/223) of the cohort. Nodal metastasis was present in 0 patients with cTis, 0 patients with cTa, and 11.6% (18/155) of patients with cT1 disease. Of the 18 patients with LNM in cT1 disease, 61% (11/18) had positive nodes below the common ileac vessel bifurcation, 6% (1/18) had positive nodes below the level of aortic bifurcation, and 33% (6/18) had distant metastasis to lymph nodes beyond aortic bifurcation. No skip metastasis were identified. After RC, 89% of cT1 with nodal metastasis had muscle invasive disease. On logistic regression analysis, presence of LVI on TURBT specimen was a significant predictor of LNM (OR 6.8, CI 2.2-20.9). Five-year RFS was 91%, 82%, and 61% in patients with pNMIBC, cNMIBC, and pMIBC, respectively. Conclusions: Routine lymph node dissection is necessary in patients undergoing RC for cT1 disease due to risk of upstaging and LNMs. Presence of LVI in TURBT specimen of cNMIBC is a predictor of nodal metastasis. In patients with nodal disease, metastasis beyond the limits of a standard lymph node template occurred in two-thirds of patients, however a standard pelvic node dissection would have identified all patients with node positive disease.

Pattern and clinical significance of lymph node metastasis from hepatocellular carcinoma.

431 Background: We investigated clinical features and prognostic significance as well as the significance of local treatment on LN metastasis from HCC. Methods: The patients diagnosed of HCC with LN metastasis from 2001 to 2019 were evaluated. The HCC was diagnosed using image study and serum tumor marker based on Korean Liver Cancer Study Group guideline. The LN metastasis was diagnosed in accordance to diagnosis criteria in imaging study. The pattern of LN metastasis was evaluated based on imaging study and stratified by 3 groups: group A, regional LN metastasis group, group B, beyond regional intra-abdomen LN metastasis and group C, extra-abdomen LN metastasis group. Results: A total of 852 patients were included. The local treatment of either resection or RT were performed in 265 patients (31.1%). The OS between 3 groups was significantly different; the 1-year OS was 39.8%, 25.5% and 22.2% for group A, B and C, respectively ( p&lt;0.001). The local treatment group presented favorable features involving better liver function, controlled primary cancer and lesser extra-nodal metastasis than no local treatment group (CP-A: 72.5% vs. 54.2%, control of primary cancer: 44.9% vs. 8.7%, extra-nodal metastasis: 85.3% vs. 52.1%, p&lt;0.001). After propensity score matching (PSM), the features were well balanced between the two groups. The OS was significantly better in the local treatment group even after PSM (1-year OS: 51.8% vs. 26.6%, p&lt;0.001). Local treatment showed superior OS in both LN only metastasis and LN plus extra-nodal metastasis (62.3% vs. 31.6% vs. 45.0% vs. 23.4%, p&lt;0.001). In LN only metastasis patients, the dynamics of disease progression showed no difference between two groups ( p=0.651). Conclusions: This study showed that the survival and pattern of failure were significantly different depending on the location of LN metastasis. In patients with regional LN metastasis, active local treatment would enhance the survival of patients.

Clinicopathologic features and lymph node metastasis pattern of the cervical MiNEN.

Mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) is a rare type of cervical tumor. Its clinicopathological features, lymph node (LN) metastatic patterns and outcomes are still unclear. We have analyzed the clinicopathological information of 26 patients with cervical MiNEN. The median age of onset for cervical MiNEN was 48 years. Macroscopically, polyps and nodules were the main types. The neuroendocrine components included small cell neuroendocrine carcinoma (SCNEC) (14/26 cases), large cell neuroendocrine carcinoma (LCNEC) (10/26 cases), and typical carcinoid (2/26 cases). Non-neuroendocrine components included adenocarcinoma (AC) (12/26, including one case of AC in situ) and squamous cell carcinoma (SC) (10/26) and adeno-squamous cell carcinoma (ASC) (4/26). Of the 16 AC cases, 15 were human papilloma virus (HPV)-associated AC and one was HPV-independent AC. Except for the case of MiNEN with HPV-independent AC, all cases were diffusely and strongly positive for p16 protein. The lympho-vascular space invasion (LVSI) was seen in 17/26 cases, and the components that invade lymphatic vessels were mainly neuroendocrine carcinomas (NECs) (15/17), followed by SC (1/17) and AC (1/17). Ten patients developed LN metastases, including six in combined SCNECs (6/14) and four in combined LCNECs (4/10); the metastatic component was pure NEC in eight cases (8/10) and SC or AC in two cases (2/10). NEC component is the key factor that determines the clinical behavior and prognosis of cervical MiNEN.

Clinical implications of lymphadenectomy for invasive ductal carcinoma of the body or tail of the pancreas.

AimThe appropriate extent of lymphadenectomy for pancreatic cancer of the body/tail has not been standardized worldwide. The present study evaluated the optimal extent of harvesting lymph nodes.MethodsPatients who underwent distal pancreatectomy for invasive ductal carcinoma of the pancreas between 2007 and 2018 were retrospectively reviewed. Patients were subclassified into three groups depending on the tumor location: pancreatic body (Pb), proximal pancreatic tail (Ptp), and distal pancreatic tail (Ptd). The pancreatic tail was further divided into even sections of Ptp and Ptd. Patterns of lymph node metastasis and the impact of lymph node metastasis on the prognosis were examined.ResultsA total of 120 patients were evaluated. Fifty‐eight patients had a tumor in the Pb, 38 in the Ptp, and 24 in the Ptd. No patients with a Ptd tumor had metastasis beyond the peripancreatic and splenic hilar lymph nodes (LN‐PSH). All patients with metastasis to the lymph nodes along the common hepatic artery (LN‐CHA) or along the left lateral superior mesenteric artery (LN‐SMA) also had metastasis to the LN‐PSH. Recurrence after surgery occurred significantly earlier in this population. In a multivariate analysis, metastasis to the LN‐CHA or LN‐SMA (hazard ratio [HR] 3.3; P = .04) was an independent risk factor for overall survival. Furthermore, high levels of preoperative serum CA19‐9 (HR 10.9; P = .013) were a predictive factor for metastasis to the LN‐CHA or LN‐SMA.ConclusionsMetastasis to the LN‐CHA or LN‐SMA was rare but a significant prognostic factor in patients with pancreatic body/tail cancer.

Patterns of lymph node metastases and their implications in individualized radiotherapeutic clinical target volume delineation of regional lymph nodes in patients with endometrial cancer.

Purpose: To study the patterns of lymph node metastasis (LNM) of endometrial cancer (EC) and to clarify the individualized clinical target volume delineations of regional lymph nodes (CTVn). Methods: Data from a total of 556 patients with EC who had undergone total hysterectomy associated with bilateral salpingo-oophorectomy (TH/BSO) and systematic lymphadenectomy were retrospectively examined. The clinicopathological factors related to LNM were analyzed using logistic regression analysis. Results: LNM was found in 76 of 556 patients, resulting in a metastasis rate of 13.67%. The rates of LNM in patients with fundus and cornua lesions were 7.56% for para-aortic nodes and 14.41% for pelvic lymph nodes. The rates of LNM in patients with sidewall lesions were 3.15% for para-aortic nodes and 10.22% for pelvic lymph nodes. The rates of LNM in patients with lower uterine segment and cervix lesions were 12.50% for para-aortic nodes and 26.67% for pelvic lymph nodes. Deep myometrial invasion, histological type, histological differentiation, and lymphovascular space invasion (LVSI) emerged as statistically significant risk factors for pelvic LNM of EC (P = 0.008, 0.015, < 0.001, 0.005, respectively). Grade 3 differentiation had a strong influence on LNM to the para-aortic nodes (P = 0.015). Conclusions: Myometrial invasion, histological type, histological differentiation, and LVSI were related to pelvic LNM and grade 3 was associated with para-aortic LNM. These factors should be considered comprehensively to design the CTVn for intensity-modulated radiation therapy (IMRT) of EC. For patients with lower uterine segment/cervix and fundus/cornua lesions, delineating the irradiation field of the para-aortic nodal region may confer a benefit.

A survey of lymph node involvement under preoperative medical imaging in cervical cancer patients

Objective: To investigate the characteristics and distribution patterns of clinically metastatic nodes assessed by Computed Tomography (CT) in preoperative cervical cancer patients; to address the importance of obturator and/or inguinal lymph nodes as sentinel lymph nodes. Methods: A total of 217 patients with cervical carcinoma treated by lymph node dissection (LND) between 2009 and 2014 were included. All preoperative CT/MRI (Magnetic Resonance Imaging) imaging data of these patients were reviewed. The relationship of patient characteristics age, tumor stages, and corresponding lymph node metastasis status were analyzed. We put emphasis on the distribution pattern of positive lymph nodes from pre-operative imaging and compared the different frequencies of each regional and non-regional lymph node group respectively. The data of the 5-year survival rate from follow-up was taken into consideration too. SPSS 24.0 (IBM Corp., Chicago, IL, USA) was used for statistical analysis. Results: The overall lymph node metastasis (LNM) rate was 92.6% in 217 cases. When regional nodes were involved, obturator groups were concerned in 154 (76.6%). The inguinal group was involved in 146 (72.6%) in the area of non-regional lymph node. The 5-year survival rates of return visits were 92.6% and 82.1% in stage IB and IIA, respectively. Age distribution was not associated with the International Federation of Gynecology and Obstetrics (FIGO) stage as well as the incidence and patterns of nodal metastasis. Conclusions: obturator and inguinal groups play a decisive role in the metastases process of cervical cancer, and can be regarded as a candidate for sentinel lymph nodes.

Locoregional Extension Patterns of Nasopharyngeal Carcinoma Detected by FDG PET/MR.

PurposeWe sought to define the locoregional extension patterns of nasopharyngeal carcinomas (NPCs) by positron emission tomography (PET)/magnetic resonance imaging (MRI) and to improve clinical target volume (CTV) delineation.MethodsBetween May 2017 and March 2021, 331 consecutive patients with nonmetastatic NPCs who underwent pretreatment, simultaneous whole-body PET/MRI for staging were included in this study.ResultsThe high-risk regions included the base of the sphenoid bone, the prestyloid compartment, prevertebral muscle, foramen lacerum, medial pterygoid plate, sphenoidal sinus, clivus, petrous apex, and foramen ovale. When the high-risk regions were invaded, the incidence rates of tumor invasion into the medium-risk regions increased. In contrast, when the high-risk regions were not involved, the incidence rates of tumor invasion into the medium-risk regions were mostly less than 10%, excluding the post-styloid compartment and oropharynx. According to the updated consensus guidelines of the neck node levels for head and neck tumors from 2013, level IIa (77.3%, 256/331), level IIb (75.8%, 251/331), and level VIIa (71.3%, 236/331) were the most frequently involved levels, followed by levels III (42.6%), Va (13.9%), IVa (8.8%), IVb (3.6%), Ib (3.6%), Vb (2.4%), VIIb (2.4%), VIII (1.8%), Vc (0.9%), and Xa (0.3%). Skip lymph node metastasis occurred in only 1.9% of patients.ConclusionsFor NPCs, primary disease and regional lymph node spread follow an orderly pattern, and a skip pattern of lymph node metastasis was unusual. Involved level radiotherapy might be feasible for cervical lymph node levels below the caudal border of cricoid cartilage and level VIIb.

Clinicopathological characteristics of papillary thyroid cancer located in the isthmus with Delphian lymph node metastasis

Papillary thyroid carcinomas (PTC) arising from the isthmus have aggressive clinical and pathological features, especially regarding the Delphian lymph node (DLN), which are associated with poor overall and disease-specific survival of patients with head and neck cancer. In the present study, we evaluated clinicopathological characteristics in 195 DLN-positive isthmus PTCs (14.9%) and their lymph node metastatic pattern in 1305 isthmus PTC patients in our hospital between January 2016 and July 2019. Furthermore, a multivariate analysis was conducted to investigate independent risk factors for isthmus PTC with a positive DLN. The results showed that a positive DLN was significantly related to tumour size, extrathyroid extension, median number of DLN, and metastasis to the central, bilateral central, lateral, and pretracheal lymph nodes. Meanwhile, patients with DLN-positive PTC had a significantly increased incidence of suspected preoperative lymph node status than patients with DLN-negative PTC. Multivariate logistic regression of DLN metastasis in PTC located in the isthmus showed that tumour size, extrathyroid extension, and metastasis to the central, bilateral central, lateral, and pretracheal lymph nodes, were independent risk factors.

Narrative review of patterns of lymphatic drainage in early-stage non-small cell lung cancer

: In non-small cell lung cancer (NSCLC), the presence of metastatic nodal disease has been shown to be the most important predictor of long-term disease-specific survival after surgical resection. In patients with early stage, node-negative NSCLC who undergo complete resection, the current standard of care, a significant portion have recurrence of disease within 24 months after surgery. This has raised interest in better understanding the lymphatic drainage of these cancers to determine the exact patterns of loco-regional spread, and whether sentinel lymph node (SLN) identification can be utilized to aid in management of these diseases. Anatomic studies that have attempted to map the lymphatic drainage of tumors from different locations within the lung have revealed patterns of direct mediastinal drainage, which may help explain the prevalence of skip metastases, which is the presence of N2 disease in the absence of N1 disease. This article will provide a narrative review of primary literature concerning the anatomy of the pulmonary lymphatic system, patterns of nodal metastasis in NSCLC as studied through various techniques (including blue dye, radiocolloid tracers, and near-infrared image-guided SLN mapping), and opportunities for improvement in our understanding of how lung tumors interact with the lymphatic system on a structural level.

EMT-related genes are unlikely to be involved in extracapsular growth of lymph node metastases in gastric cancer

BackgroundIn gastric cancer (GC), extracapsular growth (ECG) pattern of lymph node metastases is associated with decreased overall survival rates compared to intracapsular lymph node metastases (ICG). Epithelial-to-mesenchymal transition (EMT) plays a pivotal role in hematogenous metastatic spread. Aim of the present study was to analyze if EMT related genes are involved in the growth pattern of lymph node metastases in GC. MethodsOut of our prospective database with 529 patients who underwent surgical resection for GC between 2002 and 2014 forty lymph node positive patients were identified (20 ECG, 20 ICG). The expression of 84 EMT-associated genes were analyzed by RT2 Profiler PCR Array (n = 20). Results were validated by Real-Time PCR (n = 20). ResultsGC with ECG showed differently expressed EMT related genes. GC leading to ECG showed an upregulation of three and downregulation of eleven genes. Those differences, however, could not be confirmed in PCR analysis. ConclusionsThis study demonstrates that EMT related genes are not responsible for the different growth patterns of lymph node metastases in GC. Further studies are required to evaluate the underlying mechanisms of ECG in GC as it might provide a potential therapeutic target for this subgroup of more aggressive tumors in the future.

Cancer of Pharyngoesophageal Junction: A Different Subtype From Hypopharyngeal and Cervical Esophageal Cancer?

BackgroundSquamous cell cancers in the hypopharynx (HP) and cervical esophagus (CE) are different diseases with different staging systems and treatment approaches. Pharyngoesophageal junction (PEJ) tumor involves both the hypopharynx and the cervical esophagus simultaneously, but few reports focused on PEJ tumors. This study aimed to clarify clinical characteristics and the treatment approaches of PEJ tumors.Patients and MethodsA total of 222 patients with squamous cell carcinoma in the HP, PEJ, and CE were collected between January 2008 and June 2018 in Fudan University Shanghai Cancer Center. We compared different lymph node metastatic patterns of three diseases above and the survival of different tumor locations, different lymph node metastasis, and different radiotherapy approaches.ResultsFor HP, PEJ, and CE cancer, the upper and middle cervical lymph node metastatic rates were 85.7%, 47.1%, and 5.8%, respectively; the lower cervical lymph node metastatic rates were 36.7%, 42.9%, and 35.0%, respectively; and the mediastinal lymph node metastatic rates were 2.0%, 72.9%, and 80.6%, respectively. The 3-year overall survival rates were 69.5% in the HP group, 52.0% in the PEJ group, and 69.6% in the CE group (p = 0.024). No survival differences were found between the involved-field-irradiation and elective-node-irradiation subgroups among PEJ tumors (p = 0.717 for OS and p = 0.454 for PFS, respectively).ConclusionHP cancers had a high prevalence in all cervical lymph node metastases, while CE cancers had a lower prevalence in the cervical and mediastinal lymph node metastases. PEJ cancer had the combined metastatic patterns of both HP and CE cancers. Involved field irradiation was feasible in chemoradiotherapy for PEJ cancers.

Implications of Isolated Para-Aortic Lymph Node Metastasis in Endometrial Cancer: A Large-Scale, Multicenter, and Retrospective Study

Objective: To systematically evaluate lymph node metastasis (LNM) patterns in patients with endometrial cancer (EC) who underwent complete surgical staging, which included systematic pelvic and para-aortic lymphadenectomy.Methods: Four thousand and one patients who underwent complete surgical staging including systematic pelvic and para-aortic lymphadenectomy for EC were enrolled from 30 centers in China from 2001 to 2019. We systematically displayed the clinical and prognostic characteristics of patients with various LNM patterns, especially the PLN-PAN+ [para-aortic lymph node (PAN) metastasis without pelvic lymph node (PLN) metastasis]. The efficacy of PAN+ (para-aortic lymph node metastasis) prediction with clinical and pathological features was evaluated.Results: Overall, 431 of the 4,001 patients (10.8%) showed definite LNM according to pathological diagnosis. The PAN+ showed the highest frequency (6.6%) among all metastatic sites. One hundred fourteen cases (26.5%) were PLN-PAN+ (PAN metastasis without PLN metastasis), 167 cases (38.7%) showed PLN+PAN-(PLN metastasis without PAN metastasis), and 150 cases (34.8%) showed metastasis to both regions (PLN+PAN+). There was also 1.9% (51/2,660) of low-risk patients who had PLN-PAN+. There are no statistical differences in relapse-free survival (RFS) and disease-specific survival (DSS) among PLN+PAN-, PLN-PAN+, and PLN+PAN+. The sensitivity of gross PLNs, gross PANs, and lymphovascular space involvement (LVSI) to predict PAN+ was 53.8 [95% confidence interval (CI): 47.6–59.9], 74.2 95% CI: 65.6–81.4), and 45.8% (95% CI: 38.7–53.2), respectively.Conclusion: Over one-fourth of EC patients with LMN metastases were PLN-PAN+. PLN-PAN+ shares approximate survival outcomes (RFS and DSS) with other LNM patterns. No effective clinical methods were achieved for predicting PAN+. Thus, PLN-PAN+ is a non-negligible LNM pattern that cannot be underestimated in EC, even in low-risk patients.

Prognostic Factors and Lymph Node Metastasis Patterns of Primary Duodenal Cancer.

The effectiveness and extent of regional lymph node dissection in primary duodenal cancer (DC) remains unclear. This study aimed to analyze the prognostic factors and lymph node metastasis (LNM) patterns in DC. Fifty-three patients who underwent surgical resection for DC between January 1998 and December 2018 at two institutions were retrospectively analyzed. Univariate and multivariate analyses were performed on the prognostic factors of resected DC. Moreover, the relationships between depth of tumor invasion and incidence of LNM and between tumor location and LNM stations were analyzed. The five-year survival rate of the study population was 68.9%. Multivariate survival analysis demonstrated that histologic grade G2-G4, presence of LNM, pT3-4, and elevated preoperative CA19-9 were the independent poor prognostic factors. No patient with pTis-T2 had LNM. On the other hand, LNM was found in 70% of patients with pT3-4. Among 36 patients who underwent pancreaticoduodenectomy (PD), LNM around the pancreatic head was observed, regardless of the duodenal cancer site, including the duodenal bulb and the third to the fourth portion. Histologic grade G2-G4, presence of LNM, pT3-T4, and elevated preoperative CA19-9 were the independent poor prognostic factors in patients with resected DC. Our results suggested that lymph node dissection could be omitted for DC Tis-T1a. Moreover, based on the high frequency of LNM in T3-4 cases, PD with lymph node dissection in the pancreatic head region was considered necessary for T3-4 DC at any site.

Lymph node metastasis pattern and significance of left gastric artery lymph node dissection in esophagectomy for esophageal cancers

PurposeTo investigate the lymph node metastasis pattern and significance of dissection of the left gastric artery lymph nodes in radical en bloc esophagectomy for esophageal squamous carcinomas based on the lymphatic drainage pathway revealed by carbon nanoparticle labeling.Materials and methodsPatients who underwent en bloc esophagectomy endoscopically were retrospectively enrolled. Carbon nanoparticles were injected in the submucosa of upper thoracic esophagus to label the relevant draining lymph nodes. The clinical data, lymph nodes dissected, surgical technique, and complications were analyzed.ResultsEn bloc esophagectomy was successful in all 179 patients. Metastases to the left gastric artery lymph nodes were positive in 42 patients (23.5%) but negative in 137 (76.5%). The left gastric lymph nodes were labeled, whereas no celiac lymph nodes were labeled by carbon nanoparticles. A total of 4652 lymph nodes were resected, with 26 lymph nodes per patient. Seventy-three patients had lymph node metastasis (73/179). Seventeen patients had metastasis to the recurrent laryngeal nerve lymph nodes (9.5%). The metastasis rate of the lower thoracic esophageal cancer to the left gastric artery lymph nodes was 37.0%, significantly greater than that at the middle (15.4%) or upper (6.7%) thoracic segment. The lymph node metastasis rate was significantly (P < 0.05) increased with the length of the cancerous lesion, infiltration depth, and poor differentiation. Univariate analysis revealed that the metastasis rate to the left gastric artery lymph nodes was significantly (P < 0.05) associated with paraesophageal lymph node metastasis, para-cardial lymph metastasis, and TNM classification. Multivariate analysis indicated that cancer location (odds ratio 8.32, 95% confidence interval 2.12–32.24) was significantly (P < 0.05) associated with metastasis to the left gastric artery lymph nodes, with the cancer at the middle and lower thoracic segments significantly more than in the upper thoracic segment.ConclusionCertain patterns exist in lymph node metastasis of esophageal cancer, and in radical esophagectomy of esophageal cancers, dissection of the left gastric artery lymph nodes is necessary to prevent possible residual or metastasis of esophageal squamous carcinomas based on the lymphatic drainage pathway of esophageal carcinomas demonstrated by carbon nanoparticle labeling.

MA17.02 Visualization of Patterns of Lymph Node Metastases in Non-Small Cell Lung Cancer Using Network Graph Analysis

We visualized complicated patterns of lymph node metastases in surgically resected non-small cell lung cancer. Preliminary results will be presented in Japanese at the 38th Annual Meeting of the Japanese Association for Chest Surgery on May 2021 and in English at this conference.

A modified pathological N1 classification strategy based on the systematic dissection of N1 nodes for non-small cell lung cancer

The Tumor, Node, Metastasis (TNM) staging system has been adopted by the Union for International Cancer Control (UICC) and the American Joint Committee on Cancer (AJCC) for approximately 50 years. The N1 descriptor has rarely been modified since it was first proposed. Nevertheless, heterogeneity of the N1 disease should be prioritized because the survival outcomes vary greatly in N1 cohort. It has been discovered that prognostic differences exist between various patterns of N1 lymph node metastasis in previous studies. However, the absence of stations 13/14 lymph nodes data has always been an urgent problem to be solved. On the premise of complete intrapulmonary lymph node retrieval, based on the clinical experience our team had accumulated, we used subcategories within the N1 descriptor based on the location of involved N1 lymph nodes. We defined new N1a as involvement of peripheral zone lymph nodes (stations 12-14), and new N1b as involvement of hilar zone lymph nodes (stations 10-11). This new system could improve the ability to identify the heterogeneity of N1 disease. We propose that this modified classification strategy can be used as a more effective N1 descriptor.