Hilar Node Metastasis Research Articles

A clinicopathologic feature-based nomogram for preoperative estimation of splenic hilar lymph node metastasis in advanced proximal gastric cancer without invasion of the greater curvature

BackgroundThe indications for splenic hilar lymph node dissection in advanced proximal gastric cancer without invasion of the greater curvature are controversial. We aimed to develop a preoperative nomogram for individualized prediction of splenic hilar lymph node metastasis in non–greater curvature advanced proximal gastric cancer. MethodsFrom January 2014 to December 2021, 558 patients with non–greater curvature advanced proximal gastric cancer who underwent D2 lymphadenectomy (including splenic hilar lymph node) were retrospectively analyzed and divided into a training cohort (n = 361) and validation cohort (n = 197), depending on the admission time. A preoperative predictive nomogram of splenic hilar lymph node metastasis was established based on independent predictors identified by multivariate analysis, and the performance and prognostic value were confirmed. ResultsIn the training and validation cohorts, 48 (13.3%) and 24 patients (12.2%) had pathologically confirmed splenic hilar lymph node metastasis, respectively. Tumor located in the posterior wall, tumor size ≥5 cm, Borrmann type IV, and splenic hilar lymph node lymphadenectasis on computed tomography were preoperative factors independently associated with splenic hilar lymph node metastasis. The nomogram developed based on these four parameters had a high concordance index of 0.850 (95% confidence interval, 0.793–0.907) and 0.825 (95% confidence interval, 0.743–0.908) in the training and validation cohorts, respectively, with well-fitting calibration plots and better net benefits in the decision curve analysis. In addition, disease-free survival and overall survival were significantly shorter in the high-risk group, with hazard ratios of 3.660 (95% confidence interval, 2.228–6.011; log-rank P < .0001) and 3.769 (95% confidence interval, 2.279–6.231; log-rank P < .0001), respectively. ConclusionThe nomogram has good performance in predicting the risk of splenic hilar lymph node metastasis in non–greater curvature advanced proximal gastric cancer preoperatively, which can help surgeons make rational clinical decisions.

Anaplastic Lymphoma Kinase (ALK) Inhibitors Show Activity in Colorectal Cancer With ALK Rearrangements: Case Series and Literature Review.

Anaplastic lymphoma kinase (ALK) rearrangement is a well-known driver oncogene detected in approximately 5% of non-small cell lung cancer. However, ALK rearrangement is much less frequent in other solid tumors outside the lungs, such as colorectal cancer (CRC); thus, the optimal management of CRC with ALK rearrangements has yet to be established. In this report, we describe 2 cases of ALK-positive CRC, both of which benefited from ALK tyrosine kinase inhibitor (ALK-TKI) therapy. Case 1 was a postoperative patient with poorly differentiated colon adenocarcinoma, who was diagnosed with metastatic relapse shortly after surgery. Both fluorouracil, leucovorin, and oxaliplatin (FOLFOX) and bevacizumab combined with 5-fluorouracil, l-leucovorin, and irinotecan (FOLFIRI) proved ineffective against the disease. The patient was then treated with ensartinib, as the CAD-ALK fusion gene was detected by genomic analysis. The patient was initially treated with ensartinib monotherapy for 9 months, then with ensartinib combined with local radiotherapy and fruquintinib for another 4 months for isolated hilar hepatic lymph node metastasis. The patient experienced disease progression with an acquired ALK G1202R resistance mutation that responded well to lorlatinib. Case 2 involved a 72-year-old man with advanced colon cancer (pT4bN2aM1b, stage IV) harboring an EML4-ALK fusion. The patient underwent resection of the right colon tumor due to intestinal obstruction, but the disease continued to progress after 12 courses of FOLFIRI and bevacizumab chemotherapy. However, the patient responded remarkably well to alectinib. Our report emphasizes the importance of gene detection in the treatment of malignant tumors, and the significance of ALK mutations in CRC.

Clinical risk factors for splenic hilar nodal metastasis in remnant gastric cancer after distal gastrectomy.

270 Background: Splenectomy is usually considered to be required for complete dissection of splenic hilar lymph node (#10 LN) in gastric cancer (GC). Although spleen-preserving D2 was established for the advanced GC not invading the grater coverture based on the JCOG0110 clinical trial, D2 gastrectomy with splenectomy remains the standard procedure for the advanced GC involving grater coverture in Japan. However, the applicability of this treatment for remnant gastric cancer (RGC) is unclear because the lymphatic flow and lymphatic metastatic pattern may have been changed after initial gastrectomy. There are no guidelines for splenic hilar nodal dissection for RGC. In this study we evaluated risk factors for #10 nodal metastasis in RGC. Methods: This study retrospectively examined RGC patients who received gastrectomy with #10 nodal dissection after distal gastrectomy at two high-volume cancer centers in Japan between 1998 and 2015. Results: 99 patients were entered in this study. The #10 nodal metastatic rate was 12.1% (12/99). Initial gastrectomy was performed for benign in 42 patients and for malignant in 52 patients. The median duration from the initial gastrectomy was 20 (1-55) years. Main tumor location was lesser curvature in 46 patients, anterior wall in 11, greater curvature in 19, posterior wall in 11, and the whole in 12. Large type 3(≥8cm) and type 4 were found in 18 cases. The median tumor size was 50 (10-232) mm. The depth of invasion was cT1 in 31 patients, cT2 in 19, cT3 in 11, cT4a in 28, and cT4b in 10. Histology was differentiated type in 46 patients and undifferentiated type in 56. Completion gastrectomy was performed in 98 patients and partial gastrectomy in 1. 89 patients underwent splenectomy. The univariate analysis showed that tumor location (lesser curvature vs others, p=0.027) and depth of invasion (cT1-3 vs cT4, p=0.032) were significant risk factors for #10 nodal metastasis. By multivariate analysis, these two factors remained significant. Metastasis to #10 nodal metastasis was 0% (0/28) in patients without both risk factors, 11-12% in those with at least one risk factor, and 30% (6/20) in those with both risk factors. Conclusions: The tumors not confined to the lesser curvature and cT4 were significant risk factors for #10 nodal metastasis of RGC after distal gastrectomy. Splenectomy should be considered for complete splenic hilar nodal dissection when these risk factors are positive.

18F-FAPI PET/CT performs better in evaluating mediastinal and hilar lymph nodes in patients with lung cancer: comparison with 18F-FDG PET/CT

BackgroundThe aim of this study was to evaluate the efficacy of fluorine 18 (18F) labeled fibroblast activation protein inhibitor (FAPI) in identifying mediastinal and hilar lymph node metastases and to develop a model to quantitatively and repeatedly identify lymph node status.MethodsTwenty-seven patients with 137 lymph nodes were identified by two PET/CT images. The sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of lymph node status were analyzed, and the optimal cut-off value was identified by ROC analysis.ResultsThe SUVmax of metastatic lymph nodes on 18F-FAPI was higher than that on 18F-FDG PET/CT (10.87 ± 7.29 vs 6.08 ± 5.37, p < 0.001). 18F-FAPI presented much greater lymph node detection sensitivity, specificity, accuracy, PPV and NPV than 18F-FDG PET/CT (84% vs. 71%; 92% vs. 67%; 90% vs. 69%, 84% vs. 52%, and 92% vs. 83%, respectively). Additionally, the diagnostic effectiveness of 18F-FAPI in small lymph nodes was greater than that of 18F-FDG PET/CT (specificity: 96% vs. 72%; accuracy: 93% vs. 73%; PPV: 77% vs. 33%, respectively). Notably, the optimal cut-off value for specificity and PPV of 18F-FAPI SUVmax was 5.3; the optimal cut-off value for sensitivity and NPV was 2.5.Conclusion18F-FAPI showed promising diagnostic efficacy in metastatic mediastinal and hilar lymph nodes from lung cancer patients, with a higher SUVmax, especially in small metastatic nodes, compared with 18F-FDG. In addition, this exploratory work recommended optimal SUVmax cutoff values to distinguish between nonmetastatic and metastatic lymph nodes, thereby advancing the development of image-guided radiation.Trial registration ClinicalTrials.gov identifier: ChiCTR2000036091.

Risk evaluation of splenic hilar lymph node metastasis and survival analysis of patients with advanced gastric cancer

Abstract Background There is no consensus regarding the influence of prophylactic no. 10 lymph node (LN) dissection in patients with advanced gastric cancer (AGC). We aimed to evaluate whether patients with AGC could benefit from no. 10 LN dissection and to explore the clinicopathological indicators of no. 10 LN metastasis. Methods We analyzed the data of 218 patients with AGC who underwent standard D2 lymphadenectomy (SD2; n = 108) or modified D2 lymphadenectomy (MD2; n = 110) between January 2017 and January 2021. In addition, we examined factors influencing no. 10 LN metastasis in the SD2 group. Results Differentiation, tumor location, and no. 4 positive LNs were significantly correlated with no. 10 LN metastasis (P &lt; 0.05). Borrmann classification, differentiation, depth of invasion, LN metastasis (N), and tumor size were found to correlate with survival in univariate analyses. Age, sex, extent of gastrectomy, tumor location, and extent of lymphadenectomy were not associated with survival (P &gt; 0.05). The median survival times were 72.23 and 68.56 months for the SD2 and MD2 groups, respectively (P = 0.635). Postoperative major morbidity and mortality rates were 37.96% and 3.70% in the SD2 group, and 23.64% and 1.82% in the MD2 group, respectively. Conclusions Based on our findings, prophylactic no. 10 lymphadenectomy may be recommended in patients with AGC who exhibit positive no. 4 LN status, poor differentiation, and tumors located on the greater curvature.

Key nodal stations for predicting splenic hilar nodal metastasis in upper advanced gastric cancer without invasion of the greater curvature.

Standard surgery for upper advanced gastric cancer without invasion of the greater curvature (UGC-GC) is spleen-preserving D2 total gastrectomy without dissection of the splenic-hilar nodes (#10). However, some patients with nodal metastasis to #10 survive more than 5 years due to nodal dissection of #10. If nodal metastasis to #10 is predictable based on the positivity of other nodes dissected by the current standard surgery without #10 nodal dissection, physicians may be able to consider #10 dissection. This study retrospectively reviewed data from the National Cancer Center Hospital in Japan between 2000 and 2012. We selected cases that met the following criteria: (1) D2 or more total gastrectomy with splenectomy, (2) UGC-GC, and (3) histological type is gastric adenocarcinoma. We performed univariate and multivariate analyses concerning lymph node stations associated with #10 metastasis. A total of 366 patients were examined. A multivariate analysis revealed that #10 metastasis was associated with positivity of the nodes along the short gastric arteries (#4sa) and distal nodes along the splenic artery (#11d) (#4sa: p = 0.003, #11d: p = 0.016). When either key node was positive, the metastatic rate of #10 was 24.4%, and the therapeutic value index was 13.3. #4sa and #11d were key lymph nodes predicting #10 nodal metastasis in UGC-GC. When these key nodes are positive on computed tomography before surgery or according to a rapid pathological examination during surgery, dissection of #10 should be considered even if upper advanced tumors are not invading the greater curvature.

Diagnostic value of endobronchial ultrasound elastography in differentiating between benign and malignant hilar and mediastinal lymph nodes: a retrospective study.

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a first-line approach for diagnosing hilar and mediastinal lymph node metastasis. Endobronchial ultrasound (EBUS) elastography is an imaging technique for describing the elasticity of intrathoracic lesions. However, the reported accuracy of EBUS elastography needs to be improved. In this study, we aimed to explore the diagnostic value of EBUS elastography for differentiating between benign and malignant hilar and mediastinal lymph nodes. We conducted a single-center, retrospective study enrolling consecutive patients who received EBUS elastography followed by EBUS-TBNA at the Chinese PLA General Hospital from October 2015 to October 2022. The pathological results of EBUS-TBNA confirmed by 6-month follow-up were used as the gold standard. The ultrasound elastography parameters of lymph nodes included strain rate, stiff area ratio, and elasticity score, along with the conventional ultrasound characteristics such as short axis diameter, shape, margin, echogenicity distribution and intensity, and blood flow. The diagnostic performance of these parameters was compared, and conjointly analyzed using multivariate logistic regression. Bootstrapping resampling was applied for internal validation of the regression model. A total of 83 patients were enrolled with an average age of 57 years, and 66.3% of patients were male. In total, 131 lymph nodes were punctured, among which 79 (60.3%) were malignant. All the conventional ultrasound characteristics were significantly different between benign and malignant lymph nodes. All the ultrasound elastography parameters of malignant lymph nodes were markedly higher than those of benign lymph nodes. Multivariate logistic regression analysis showed that the margin, echogenicity intensity, blood flow, short axis diameter, and stiff area ratio were the main factors affecting the lymph node property. The diagnostic accuracy, sensitivity, and specificity were 91.8% [95% confidence interval (CI): 85.4-96.0%], 94.4% (95% CI: 86.4-98.5%), and 88.0% (95% CI: 75.7-95.5%), respectively. Bootstrap resampling validation showed a concordance index (C-index) of 0.949. The calibration plot indicated good agreement between the predicted and observed results. EBUS elastography is a promising approach for differentiating between benign and malignant lymph nodes. The combination of conventional EBUS and elastography can improve diagnostic efficacy, provide reliable complementary information, and guide the implementation of EBUS-TBNA more accurately.

Efficacy and safety of preoperative immunotherapy alone followed by surgery in the treatment of advanced gastric cancer with MSI-H/dMMR or EBV-positive.

At present, there is no consensus on whether preoperative immunotherapy (PIT) without chemotherapy followed by surgery could benefit patients with advanced gastric cancer (AGC). Here, we report a six-case series study to describe the safety and efficacy of PIT plus gastrectomy in patients with AGC. This study involved six patients with AGC who received PIT and surgery at our center between January 2019 and July 2021. Demographic characteristics, preoperative gastroscope biopsy pathology, surgical tissue pathology, radicalness of tumor resection, surgical safety, and recovery parameters were reported. Six patients, including four patients with Epstein-Barr virus (EBV)-positive gastric cancer (GC) and two patients with microsatellite instability-high (MSI-H)/expression deficiency of mismatch repair (dMMR) protein GC, were enrolled in this study. Four patients experienced immunotherapy-related adverse events (irAEs), without severe adverse events (SAEs). Five patients underwent R0 resection, and one patient underwent palliative gastrectomy due to liver and hilar lymph node metastasis. Pathologic responses from the surgical tissue were observed in all patients, including two pathological complete response (pCR). No operative complications or postoperative deaths occurred. Three patients (50%) experienced mild or moderate postoperative complications without severe postoperative complications. All six patients eventually recovered and were discharged. This study indicated that PIT was effective and tolerant in some patients with MSI-H/dMMR and/or EBV-positive AGC. PIT followed by gastrectomy might be an alternative treatment option for these selected patients.

Evaluation of the incidence of splenic hilar lymph node metastasis in patients operated on for esophagogastric junction cancer

Evaluation of the incidence of splenic hilar lymph node metastasis in patients operated on for esophagogastric junction cancer

The Role Of Serum Uric Acid And Uric Acid To Albumin Ratio For Predicting Of Lymph Node Metastasis In Lung Cancer Treated Surgically By Vats.

In recent years, a correlation between prognosis of various cancers and inflammation has been emphasized in many studies. Uric acid which is a purine metabolite is one of the serum inflammation markers. Albumin is a major component of serum protein and it is used as a parameter reflecting nutritional status and cancer aggressiveness. Here, we have investigated whether preoperative serum uric acid levels, albumin levels, and uric acid to albumin ratio predict lymph node metastasis in non-small cell lung cancer treated surgically by VATS. The medical records of patients underwent VATS lobectomy-segmentectomy for non-small cell lung cancer between January 2015 and December 2020, were reviewed retrospectively. Cut-off values of preoperative serum uric acid, albumin and uric acid to albumin ratio were determined by Receiver Operating Characteristics (ROC) analysis. Groups with and without lymph node metastasis were created according to hilar and/or mediastinal lymph node metastasis. In addition, high and low groups were created according to preoperative uric acid levels and uric acid to albumin ratio. Pearson chi-square test was used investigate whether any significant correlation between the groups. A total of 115 patients were included in the study. Lymph node metastasis in N1 and N2 stations was detected in 11 and 18 patients, respectively. Cut-off values for uric acid and uric acid to albumin ratio were 5.97 mg/dL and 1.28x10-3, respectively. There was a statistically significant correlation between lymph node metastasis and high uric acid levels (p=0.008, OR: 3.2) and high uric acid to albumin ratio (p=0.03, OR: 2.6). Preoperative serum uric acid and uric acid to albumin ratio can predict the lymph node metastasis in non-small cell lung cancer treated surgically by video assisted thoracic surgery.

Prevention and management of complications related to laparoscopic spleen-preserving hilar lymph node dissection for gastric cancer

Hilar splenic lymph node metastasis is one of the risk factors for poor prognosis in patients with proximal gastric cancer. Laparoscopic spleen-preserving splenic hilar lymph node dissection (LSPSHLD) can effectively improve the survival benefits of patients at high risk of splenic hilar lymph node metastasis. However, LSPSHLD is still a challenging surgical difficulty in radical resection of proximal gastric cancer. Moreover, improper operation can easily lead to splenic vascular injury, spleen injury and pancreatic injury and other related complications, due to the deep anatomical location of the splenic hilar region and the intricate blood vessels.Therefore, in the prevention and treatment of LSPSHLD-related complications, we should first focus on prevention, clarify the indication of surgery, and select the benefit group of LSPSHLD individually, so as to avoid the risk caused by over-dissection. Meanwhile, during the perioperative period of LSPSHLD, it is necessary to improve the cognition of related risk factors, conduct standardized and accurate operations in good surgical field exposure and correct anatomical level to avoid surrounding tissues and organs injury, and master the surgical skills and effective measures to deal with related complications, so as to improve the surgical safety of LSPSHLD.

Selective Mediastinal Lymph Node Dissection Strategy for Clinical T1N0 Invasive Lung Cancer: A Prospective, Multicenter, Clinical Trial

IntroductionWe aimed to prospectively evaluate our previously proposed selective mediastinal lymph node (LN) dissection strategy for peripheral clinical T1N0 invasive NSCLC. MethodsThis is a multicenter, prospective clinical trial in China. We set six criteria for predicting negative LN stations and finally guiding selective LN dissection. Consolidation tumor ratio less than or equal to 0.5, segment location, lepidic-predominant adenocarcinoma (LPA), negative hilar nodes (stations 10–12), and negative visceral pleural invasion (VPI) were used separately or in combination as predictors of negative LN status in the whole, superior, or inferior mediastinal zone. LPA, hilar node involvement, and VPI were diagnosed intraoperatively. All patients actually underwent systematic mediastinal LN dissection. The primary end point was the accuracy of the strategy in predicting LN involvement. If LN metastasis occurred in certain mediastinal zone that was predicted to be negative, it was considered as an “inaccurate” case. ResultsA total of 720 patients were enrolled. The median number of LN dissected was 15 (interquartile range: 11–20). All negative node status in certain mediastinal zone was correctly predicted by the strategy. Compared with final pathologic findings, the accuracy of frozen section to diagnose LPA, VPI, and hilar node metastasis was 94.0%, 98.9%, and 99.6%, respectively. Inaccurate intraoperative diagnosis of LPA, VPI, or hilar node metastasis did not lead to inaccurate prediction of node-negative status. ConclusionsThis is the first prospective trial validating the specific mediastinal LN metastasis pattern in cT1N0 invasive NSCLC, which provides important evidence for clinical applications of selective LN dissection strategy.

Survival outcome of upfront surgery for clinical single-station N2 non-small cell lung cancer.

Pathological N2 (pN2) non-small cell lung cancer (NSCLC) is diverse; its treatment depends on the clinical N (cN) status. We aimed to determine the efficacy of upfront surgery for cN2pN2 NSCLC. The study included 43 cN2pN2 NSCLC patients who underwent upfront surgery at the Shizuoka Cancer Center between 2002 and 2017. Survival outcome, focusing on cN2 status, was retrospectively investigated. Mediastinal lymph nodes were pre-operatively evaluated using computed tomography and positron emission tomography. Surgical eligibility criteria included single-station cN2. N2 with N1 and skip N2 were defined as N2 with and without ipsilateral hilar lymph node metastasis, respectively. A platinum-doublet regimen was used for adjuvant chemotherapy. Survival curves were analysed using the Kaplan-Meier method. Univariate and multivariate analyses were performed using the Cox proportional hazard regression model. Clinical-skip N2 and cN2 with N1 cases included 22 and 21 patients, respectively. Twenty-three patients received adjuvant chemotherapy. The median follow-up duration was 73months. Clinical-skip N2 had a significantly better 5-year recurrence-free survival (RFS) than cN2 with N1 (58.3 vs 28.6%, P = 0.038) and was an independent favorable RFS predictor. Recurrence within 18 months occurred in 71% of cN2 with N1 cases. Five-year overall survival and RFS rates in patients receiving adjuvant chemotherapy vs those without adjuvant chemotherapy were 82.2 vs 41.9% (P = 0.019) and 56.5 vs 28.0% (P = 0.049), respectively. Clinical-skip N2 had an excellent prognosis, and upfront surgery was acceptable. Conversely, upfront surgery followed by chemotherapy is not recommended for cN2 with N1 patients because of early recurrence.

Impact of tumor location and pleural invasion on the frequency of skip hilar lymph node metastasis in lung cancer.

The appropriate extent of hilar lymph node (LN) dissection in segmentectomy for lung cancer has not yet been fully investigated. Herein, we assessed the patterns of LN metastasis using network analyses. Patients with nodal metastases of non-small-cell lung cancer measuring ≤30 mm in diameter who underwent anatomical resection were included. The assumed pathways of metastasis were visualized using Cytoscape software. Metastasis to hilar (#10) or interlobar (#11) LNs but not to more peripheral ones was defined as skip N1 metastasis. A total of 322 patients were included, with 123 of them having pleural invasive tumors and 32 having intrapulmonary metastases. There were 130 patients with pN1 disease and 192 with pN2 disease. The overall proportion of patients with skip N1 metastasis was 17%. Patients with lower lobe tumors had more frequent skip N1 metastasis than those with upper lobe tumors (31% vs. 10%, P<0.001) but had less frequent skip N2 metastasis (10% vs. 20%, P=0.02). The rates of skip metastasis to #11i in the right S6 tumor and right S9-10 tumor were unexpectedly high (22% and 17%, respectively). Similarly, skip metastasis to #11 in the left S6 tumor was relatively high (16%). There was a significant difference in the frequency of skip LN metastasis between tumors with and without pleural invasion (44% vs. 27%, P=0.001). The pattern of LN metastasis differed according to the localized segment of the tumor and the pleural invasion status.

Tumour location predicts occult N1 nodal metastasis in clinical stage I non-small-cell lung cancer.

Pathological lymph node metastases are often observed in patients with clinical N0 lung cancer. Identifying preoperative predictors of occult hilar nodal metastasis (OHNM) is important in determining the surgical procedure in patients with clinical stage I non-small-cell lung cancer. This study aimed to determine the frequency and predictors of OHNM by tumour location in these patients. Between April 2007 and May 2019, data of patients who underwent lobectomy or segmentectomy for clinical stage I pure-solid non-small-cell lung cancer were retrospectively reviewed. The ratio of the distance from the pulmonary hilum to the proximal side of the tumour to the distance from the pulmonary hilum to the visceral pleural surface through the centre of the tumour, named 'distance ratio (DR)', was calculated. The relationship of the DR with clinicopathological findings and prognosis was discussed. A total of 357 patients were enrolled. OHNM frequency was 14.6%. Patients were divided into 2 groups based on whether the DR was ≤0.67 (central type) or >0.67 (peripheral type). The frequency of OHNM was significantly higher in the DR ≤0.67 group (21.5% vs 7.4%; P < 0.001). Multivariable analysis revealed that DR was the only independent preoperative predictor of OHNM (odds ratio, 3.63; 95% confidence interval, 1.83-7.18; P < 0.001). The frequency of OHNM was significantly lower in peripheral-type lung cancer; therefore, tumour location was the most important preoperative predictor of OHNM.

Assessment of lymph node metastasis of ≤20 mm non‐small cell lung cancer originating from superior segment compared to basal segment

Segmentectomy with curative intention is occasionally performed for early non-small cell lung cancer (NSCLC). However, a major problem has been pointed out, in that the rate of locoregional recurrence is higher after segmentectomy than after lobectomy. This study aimed to investigate differences in rates of lymph node metastasis between segment 6 and basal segment NSCLC as potential candidates for segmentectomy and to explore factors associated with locoregional recurrence of segmentectomy. We retrospectively analyzed 461 patients with lower lobe NSCLC who underwent segmentectomy or lobectomy with mediastinal lymph node dissection between 2011 and 2021. Among these, 122 patients with clinical N0 NSCLC, diameter ≤ 20 mm, and consolidation tumor ratio >0.5 were analyzed. The 122 patients were divided into a segment 6 group (n= 51) and a basal segment group (n= 71). Frequency of lymph node metastasis was significantly higher in the segment 6 group (17.7%) than in the basal segment group (4.2%; p= 0.01). Metastases to lymph node station 7 were seen in five of 122 patients (4.1%). Hilar lymph node metastasis occurred in nine of 122 patients (7.4%). Notably, metastases to station 11, 11i and 11 s lymph nodes were the most frequent patterns for hilar lymph nodes (41.7%). Station 11 lymph nodes are adjacent to the remaining lung segment or pulmonary artery in S6 segmentectomy or basal segmentectomy. Part of the NSCLC in segment 6 patients may thus be considered for lobectomy owing to the difficulty of complete dissection of station 11 lymph nodes.

An Essential Treatment Pattern of Lung Cancer: Magnetic Resonance-Guided Stereotactic Body Radiotherapy

<h3>Purpose/Objective(s)</h3> Stereotactic body radiation therapy (SBRT) has emerged as an important treatment for non-resectable lung cancer. MR-Linac can offer superior soft-tissue contrast, have the ability to visualize cancer physiology and daily on-table treatment adaptation. Obviously combined SBRT with MR-Linac holds the promise to improve the accuracy of radiotherapy and reduce the toxicity of organs-at-risk (OAR). However, data on treatment effect and patient acceptance is still limited. <h3>Materials/Methods</h3> Between July 2019 and October 2021,14 patients with lung cancer were treated with an MRI-Linac guided SBRT, of them, 6 in left upper lobe, 1 in left lower lobe, 2 in right upper lobe and 5 in right lower lobe. The CT simulation used a Siemens big-bore CT scanner (syngo CT VA62A) for all patients. All patients were treated with step and shoot intensity modulated radiotherapy (IMRT). The online plan was created while the patient was on the treatment table and based on the online MRI images; pre-treatment CT was deformably registered to the online MRI to obtain position error. All patients used adapt to position (ATP) workflow. The curative effect and adverse reactions in the process of treatment need to be paid close attention to, and the adverse reactions should be treated and recorded in time. <h3>Results</h3> Fourteen patients (with n=2 metastases; n=12 primary tumor) received MR-guided SBRT. Median prescribed does was 60Gy(range:54Gy-70Gy) and median planning target volume was 28.8cc (range:11.1-93.4cc). Two patients occurred grade I bone marrow suppression and two occurred grade II bone marrow suppression. One patient occurred grade I gastrointestinal toxicity. No patient occurred grade III or higher toxicity. Only one patient developed left lung recurrence and left hilar lymph node metastasis ten months after treatment, one patient was not re-examined, and others were controlled locally. <h3>Conclusion</h3> In summary, MR-guided SBRT of lung cancer is well-effective and well-accepted. The results are promising that it holds with prominent local control and mild adverse events. The influence of magnetic field on dosimetry remains to be studied. The relevant work is also conducted.

Correlation analysis between unenhanced and enhanced CT radiomic features of lung cancers presenting as solid nodules and their efficacy for predicting hilar and mediastinal lymph node metastases.

If hilar and mediastinal lymph node metastases occur in solid nodule lung cancer is critical for tumor staging, which determines the treatment strategy and prognosis of patients. We aimed to develop an effective model to predict hilar and mediastinal lymph node metastases by using texture features of solid nodule lung cancer. Two hundred eighteen patients with solid nodules on CT images were analyzed retrospectively. The 3D tumors were delineated using ITK-SNAP software. Radiomics features were extracted from unenhanced and enhanced CT images based on AK software. Correlations between radiomics features of unenhanced and enhanced CT images were analyzed with Spearman rank correlation analysis. According to pathological findings, the patients were divided into no lymph node metastasis group and lymph node metastasis group. All patients were randomly divided into training group and test group at a ratio of 7:3. Valuable features were selected. Multivariate logistic regression was used to build predictive models. Two predictive models were established with unenhanced and enhanced CT images. ROC analysis was used to estimate the predictive efficiency of the models. A total of 7 categories of features, including 107 features, were extracted. There was a high correlation between the 7 categories of features from unenhanced CT images and enhanced CT images (all r > 0.7, p < 0.05). Among them, the shape features had the strongest correlation (mean r = 0.98). There were 5 features in the enhanced model and the unenhanced model, which had important predicting significance. The AUCs were 0.811 and 0.803, respectively. There was no significant difference in the predictive performance of the two models (DeLong's test, p = 0.05). Our study models achieved higher accuracy for predicting hilar and mediastinal lymph node metastasis of solid nodule lung cancer and have some value in promoting the staging accuracy of lung cancer. Our results show that CT radiomics features have potential to predict hilar and mediastinal lymph node metastases in solid nodular lung cancer. In addition, enhanced and unenhanced CT radiomics models had comparable predictive power in predicting hilar and mediastinal lymph node metastases.

Isolated adrenocorticotropic hormone deficiency associated with sintilimab therapy in a patient with advanced lung adenocarcinoma: a case report and literature review

BackgroundSeveral immune checkpoint inhibitors have been implemented for cancer treatment which have shown some degree of antitumor effcacy, while immune-related adverse events (irAEs) that affect multiple organ functions ensue which obviously should not be neglected. Though less common than other kinds of irAEs, Immune checkpoint inhibitors (ICIs) related Isolated ACTH deficiency (IAD) may cause long-term damage to pituitary-adrenal axis. Several case reports are available about IAD during anti-PD-1 therapy. We report the first case of immune checkpoint inhibitor-induced IAD following 3 month of sintilimab therapy.Case presentationA 66-year-old Chinese man was diagnosed with stage IIIB lung adenocarcinoma with involving ipsilateral intrapulmonary and hilar lymph node metastasis. After 3 months of combination therapy of nedaplatin, pemetrexed and sintilimab, the patient presented with general fatigue, nausea and vomiting. Laboratory investigation at admission revealed hyponatremia and hypokalemia. Further investigation revealed adrenocorticotropic hormone and cortisol levels were far below than normal limits. His other pituitary hormone levels were normal, except for mild elevation of follicle stimulating hormone and estradiol. Cranic magnetic resonance imaging showed a normal pituitary gland. Isolated adrenocorticotropic hormone deficiency was diagnosed, and corticosteroid replacement therapy was administered, leading to a significant improvement of his symptoms while ACTH level maintaining low level.ConclusionsOur patient developed isolated ACTH deficiency during combination cancer treatment with chemotherapy and sintilimab. Although isolated ACTH deficiency due to anti-PD-1 including sintilimab therapy is rare occurrence, it can often cause severe clinical symptoms. Its diagnosis basically relies on clinical symptoms and endocrinological examination. Unlike traditional hypophysitis diagnosed by cranial MRI, pituitary MRI of IAD due to anti-PD-1 often indicates normal pituitary gland implying that over-reliance on imaging findings is not recommended. Even if clinical symptoms have relieved after corticosteroid replacement therapy was commenced, low levels of ACTH or cortisol could maintain for a long period which highlights the need for long term corticosteroid therapy. The purpose of the current report was to provide increased awareness of early detection and therapy of IAD.

P2.06-01 Skip Hilar Lymph Node Metastasis in Non-Small Cell Lung Cancer Has Similar Survival to N0 Disease: Need for a change in the pN sub-classification?

Previous edition of TNM lung cancer staging system divided N1 disease into two subgroups: N1a and N1b. Our study aimed to investigate the survival difference between patients with hilar lymph node metastasis only (skip metastasis) and other N1a patients.