Tumor Length Research Articles

Should the Baseline MRI Staging Criteria Differentiate Between Mucinous and Classical Rectal Adenocarcinoma?

To compare baseline MR imaging features for pre-treatment staging between rectal mucinous adenocarcinoma (RMAC) and rectal classical adenocarcinoma (RCAC), and to investigate whether the subtype of mucinous carcinoma influences MRI evaluation criteria and high-risk tumors identifying. A total of 306 patients who underwent surgical rectal cancer resection were retrospectively reviewed in the study. MR imaging parameters of the primary tumor and lymph nodes (LNs) were compared between two subtypes. Logistic regression and receiver operating characteristic analyses were performed to test significant associations between LN imaging parameters and malignant LN status in RMAC and RCAC, respectively. The length of mucinous tumors was larger than RCAC tumors in pT3 and pT4 stage. For pN0 patients, the long and short diameters of the largest LN on MRI were more likely to be larger in RCAC than RMAC. For pN+patients, the proportion of LNs exhibiting internal heterogeneity in RMAC was obviously greater than that in RCAC. The best cut-off value of the largest short diameter of malignant LNs was 6.05mm for RMAC and 8.05mm for RCAC. And the highest AUC for predicting LNs metastases based on the largest short diameter was 0.794 for RMAC using 6mm size cut-off, and 0.667 for RCAC using 8mm cut-off. The imaging features that were associated with LN metastases were different between RMAC and RCAC, and different size criteria of LNs was suggested to distinguish high-risk tumors. Clinicians should stay vigilant of LN status and take histologic subtypes into consideration before assigning clinical strategies.

소규모 기관의 전정신경초종의 수술 결과

Background: This study aims to evaluate retrospectively the surgical outcomes and associated complications of vestibular schwannoma in a low-volume, single-center institution. We intend to discuss strategies that may improve clinical outcomes in the surgical treatment of vestibular schwan-noma in low-volume medical centers and the correlation between the case volume of medical center and clinical outcomes.
 Materials and Methods: From January 2018 to December 2022, 13 patients (5 males and 8 fe-males; median age, 66 years) underwent surgery for vestibular schwannoma. The surgeries were performed by a single surgeon who initiated the clinical practice. The median length of tumors was 35 mm (range, 13-55 mm).
 Results: Among 13 patients, 10 patients (76.9%) underwent retromastoid suboccipital craniotomy, 3 patients (23.1%) underwent translabyrinthine approach, 4 patients (30.8%) underwent subtotal resection, 6 patients (46.2%) underwent near-total resection, and 3 patients (23.1%) underwent gross total resection. The facial nerve preservation rate was 84.6% (n = 11). Hearing preservation rate was 30.7% (n = 4).
 Conclusions: The surgical outcomes of vestibular schwannoma are not directly influenced by the volume of the medical institution. Instead, they are dependent on factors such as proper surgical planning, appropriate selection of surgical approaches and using intraoperative monitoring.

Sporadic vestibular schwannoma in a pediatric population: a case series.

To describe the characteristics, management, and outcomes of pediatric patients with sporadic vestibular schwannoma (sVS). This was a case series at a tertiary care center. Patients were identified through a research repository and chart review. Interventions were microsurgery, stereotactic radiosurgery (SRS), and observation. Outcome measures were tumor control, facial nerve function, and hearing. Eight patients over 2006-2022 fulfilled inclusion criteria (unilateral VS without genetic or clinical evidence of neurofibromatosis type 2 (NF2); age ≤ 21) with a mean age of 17years (14-20). Average greatest tumor length in the internal auditory canal was 9.7mm (4.0-16.1). Average greatest tumor dimension (4/8 tumors) in the cerebellopontine angle was 19.1mm (11.3-26.8). Primary treatment was microsurgery in five (62.5%) patients, observation in two (25%), and SRS in one (12.5%). Four (80%) surgical patients had gross total resections, and one (20%) had regrowth post-near total resection and underwent SRS. One observed patient and the primary SRS patient have remained radiographically stable for 3.5 and 7years, respectively. The other observed patient required surgery for tumor growth after 12months of observation. Two surgical patients had poor facial nerve outcomes. All post-procedural patients developed anacusis. Mean follow-up was 3years (0.5-7). We describe one of the largest reported cohorts of pediatric sVS in the USA. Diligent exclusion of NF2 is critical. Given the high likelihood of eventually requiring intervention and known adverse effects of SRS, microsurgery remains the preferred treatment. However, observation can be considered in select situations.

Evaluation and Prognosticationof Gd-EOB-DTPA MRI and CT in Patients With Macrotrabecular-Massive Hepatocellular Carcinoma.

Macrotrabecular-massive hepatocellular carcinoma (MTM-HCC) is highly aggressive. Comparing the diagnosis ability of CT and gadoxetate disodium (Gd-EOB-DTPA) MRI for MTM-HCC are lacking. To compare the performance of Gd-EOB-DTPA MRI and CT for differentiating MTM-HCC from non-MTM-HCC, and determine the prognostic indicator. Retrospective. Post-surgery HCC patients, divided into the training (N = 272) and external validation (N = 44) cohorts. 3.0 T, T1-weighted imaging, in-opp phase, and T1-weighted volumetric interpolated breath-hold examination/liver acquisition with volume acceleration; enhanced CT. Three radiologists evaluated clinical characteristics (sex, age, liver disease, liver function, blood routine, alpha-fetoprotein [AFP] and prothrombin time international normalization ratio [PT-INR]) and imaging features (tumor length, intratumor fat, hemorrhage, arterial phase peritumoral enhancement, intratumor necrosis or ischemia, capsule, and peritumoral hepatobiliary phase [HBP] hypointensity). Compared the performance of CT and MRI for diagnosing MTM-HCC. Follow-up occurred every 3-6 months, and nomogram demonstrated the probability of MTM-HCC. Fisher test, t-test or Wilcoxon rank-sum test, area under the curve (AUC), 95% confidence interval (CI), multivariable logistic regression, Kaplan-Meier curve, and Cox proportional hazards. Significance level: P < 0.05. Gd-EOB-DTPA MRI (AUC: 0.793; 95% CI, 0.740-0.839) outperformed CT (AUC: 0.747; 95% CI, 0.691-0.797) in the training cohort. The nomogram, incorporating AFP, PT-INR, and MRI features (non-intratumor fat, incomplete capsule, intratumor necrosis or ischemia, and peritumoral HBP hypointensity) demonstrated powerful performance for diagnosing MTM-HCC with an AUC of 0.826 (95% CI, 0.631-1.000) in the external validation cohort. Median follow-up was 347 days (interquartile range [IQR], 606 days) for the training cohort and 222 days (IQR, 441 days) for external validation cohort. Intratumor necrosis or ischemia was an independent indicator for poor prognosis. Gd-EOB-DTPA MRI might assist in preoperative diagnosis of MTM-HCC, and intratumor necrosis or ischemia was associated with poor prognosis. 4 TECHNICAL EFFICACY: Stage 2.

Predictive value of infiltrating tumor border configuration of rectal cancer on MRI

BackgroundInfiltrating tumor border configuration (iTBC) is assessed by postoperative pathological examination, thus, is not helpful for preoperative treatment strategies. The study aimed to detect iTBC by magnetic resonance imaging (MRI) and evaluate its predictive value.Materials and methodsA total of 153 patients with rectal cancer were retrospectively analyzed. Clinicopathological and MRI data mainly including tumor border configuration (TBC) on MRI, MRI-detected extramural vascular invasion (MEMVI), tumor length, tumor growth pattern, maximal extramural depth, pathology-proven lymph node metastasis (PLN) and pathology-proven extramural vascular invasion (PEMVI) were analyzed. The correlation of MRI factors with PEMVI and PLN was analyzed by univariate and multivariate logistic regression analyses. The nomograms were established based on multivariate logistic regression analysis and were confirmed by Bootstrap self-sampling. The receiver operating characteristic (ROC) curve analysis and area under the curve (AUC) were used to evaluate the diagnostic efficiency.ResultsFifty cases of PEMVI and 48 cases of PLN were found. Forty cases of PEMVI and 34 cases of PLN in 62 cases of iTBC were also found. iTBC, MEMVI and maximal extramural depth were significantly associated with PEMVI and PLN (P < 0.05). iTBC (odds ratio = 3.84 and 3.02) and MEMVI (odds ratio = 7.27 and 3.22) were independent risk factors for PEMVI and PLN. The C-indices of the two nomograms for predicting PEMVI and PLN were 0.863 and 0.752, respectively. The calibration curves and ROC curves of the two nomograms showed that the correlation between the predicted and the actual incidence of PEMVI and PLN was good. The AUCs of iTBC for predicting PEMVI and PLN were 0.793 (95% CI: 0.714–0.872) and 0.721 (95% CI: 0.632–0.810), respectively. The DeLong test showed that the predictive efficiency of the nomogram in predicting PEMVI was better than that of iTBC (P = 0.0009) and MEMVI (P = 0.0095).ConclusioniTBC and MEMVI are risk factors for PEMVI and pelvic lymph node metastasis. The nomograms based on iTBC show a good performance in predicting PEMVI and pelvic lymph node metastasis, possessing a certain clinical reference value.Trial registrationThis study was approved by the Ethics Committee of Beijing Friendship Hospital, and individual consent was waived for this retrospective analysis.

Clinical-Radiomics Nomogram for Risk Prediction of Esophageal Fistula in Patients with Esophageal Squamous Cell Carcinoma Treated by IMRT or VMAT

This study aimed to analyze the predictive factors of esophageal fistula (EF) in patients with esophageal squamous cell carcinoma (ESCC) receiving intensity-modulated radiotherapy (IMRT) or Volumetric Modulated Arc Therapy (VMAT), and to establish a prediction model for risk prediction of EF. A total of 479 patients with ESCC treated with IMRT or VMAT from 2013 to 2020 in Xijing hospital were retrospectively analyzed. A total of 43 patients with EF and 129 patients without EF were included in the analysis by 1:3 propensity score matching (time of diagnosis, gender). The clinical risk factors associated with EF were obtained based on univariate logistic regression analysis. Radiomic features were extracted and selected from pre-treatment contrast-enhance computed tomography (CT) to construct radiomic signature. The clinical-radiomics nomogram was constructed based on multivariate stepwise logistic regression. The classification performance of the model was evaluated based on 100 times of 5-fold cross validation. The median OS of the 172 patients included in the analysis was 27.8 months (range 1.3-104.9m), and the median OS of EF patients was lower than that of non-EF patients with 13.1 months (range 1.3-65.3m) vs 49.4 months (range 4.0-104.9m, p<0.001). A total of 1158 radiomics features were extracted and 8 radiomics features were finally selected. The area under the receiver operating characteristic curve (AUC) value of radiomic signature calculated by selected features for predicting EF was 0.794, and it also had the prognostic ability of OS risk stratification (median OS:17.6vs 46.6m, p<0.001). Multivariate analysis showed that the tumor length, tumor volume, T stage, lymphocyte rate and grade 4 esophagus stenosis were related to EF, and the AUC value of clinical nomogram for predicting EF was 0.849. The clinical-radiomics nomogram had the best performance in predicting EF with an AUC value of 0.896. The clinical-radiomics nomogram can predict the risk of EF in ESCC patients, and be helpful for individualized treatment of esophageal cancer.

Radical Chemoradiotherapy vs. Radical Surgery plus Adjuvant Chemotherapy or Chemoradiotherapy in Locally Advanced Primary Small Cell Carcinoma of the Esophagus: A Multicenter Retrospective Study in China

The purpose was to compare the treatment outcomes of radical chemoradiotherapy versus radical surgery plus adjuvant chemotherapy or chemoradiotherapy in locally advanced primary small cell carcinoma of the esophagus (LA-PSCCE). The hypothesis was that radical chemoradiotherapy had better overall survival (OS) than radical surgery plus adjuvant chemotherapy or chemoradiotherapy. This large-scale multicenter retrospective study in China enrolled patients with newly diagnosed LA-PSCCE (T3-4N0M0 or TanyN+M0, AJCC 8th edition) from 2008 to 2021. According to different curative treatment approaches, patients were divided into two groups: radical chemoradiotherapy (group: CRT), and radical surgery following adjuvant chemotherapy or chemoradiotherapy (group: S + CT/CRT). The propensity score match (PSM) was applied to reduce the effect of confounding biases in clinicopathological characteristics (age, gender, KPS, tumor location, tumor length, and cTNM stage). Univariate Cox-regression analysis and Kaplan-Meier curve were calculated for OS. Statistical results were summarized as hazard ratio (HR), 95% confidence interval (CI) and P value. A two-sided P < 0.05 was regarded to be statistically significant. A total of 291 patients with a median follow-up of 4.3 years were retrospectively enrolled. After PSM analysis, 94 and 94 patients were eventually included in group CRT and S + CT/CRT, respectively. Group CRT demonstrated a significantly superior survival than group S + CT/CRT (HR, 0.63; 95% CI, 0.43-0.91; P = 0.01), with a 3-year OS of 49.5% and 27.8% (P = 0.02), respectively. In secondary analysis, patients treated with radical chemoradiotherapy consistently showed significant survival benefit than those with radical surgery plus adjuvant chemoradiotherapy (HR, 0.4; 95% CI, 0.21-0.79; P = 0.008). For patients with newly diagnosed LA-PSCCE, radical chemoradiotherapy should be a preferred recommendation in real-world clinical practice.

Long-Term Results of Induction Chemotherapy for Esophageal Squamous Cell Carcinoma Receiving Concurrent Chemoradiotherapy

This study aimed to investigate the long-term clinical outcomes and toxicities of induction chemotherapy (IC) followed by concurrent chemoradiotherapy (CCRT) versus CCRT alone in patients with esophageal squamous cell carcinoma (ESCC). Between 2008 and 2022, 271 ESCC patients who received definitive CCRT (IC followed by CCRT, n = 72; CCRT alone, n = 199) were enrolled. Radiotherapy technique included intensity modulated radiation therapy (IMRT) or volumetric modulated arc therapy (VMAT). Through a propensity score matched (PSM) method, 71 patients receiving IC and CCRT were matched 1:1 to patients who received CCRT alone, according to age, gender, performance status, tumor length, and pre-treatment TN stage. The Kaplan-Meier method and Cox proportional hazards model were applied to analyze survival and prognosis. The IC + CCRT group had no improvement in 5-year overall survival (OS) rate (39.0% vs 29.3%, p = 0.360), recurrence-free survival (RFS) rate (39.0% vs 26.9%, p = 0.142), and distant metastasis-free survival (DMFS) rate (33.6% vs 27.2%, p = 0.515) compared with the CCRT group. The overall clinical response rate was 45.1% after IC in the IC + CCRT group. The IC responders (CR + PR + SD) group showed more favorable 5-year OS (41.7% vs. 14.3% vs. 29.3%, p < 0.001), RFS (41.7% vs. 14.3% vs. 26.9%, p < 0.001) and DMFS (37.3% vs. 0% vs. 27.2%, p < 0.001) compared with the IC non-responders (PD) group and the CCRT group. Besides, the 5-year OS rate (65.6% vs. 17.6% vs. 29.3%, p < 0.001), RFS rate (65.6% vs. 17.6% vs. 26.9%, p < 0.001), and DMFS rate (62.5% vs. 10.3% vs. 27.2%, p < 0.001) of the IC good responders (CR + PR) were significantly higher than that of the IC poor responders (SD + PD) and CCRT group. Multivariate analysis revealed that total radiotherapy time (≥ 49 days) and AJCC stage (Ⅲ/Ⅳ) were independent predictive factors of OS, RFS and DMFS. Besides, age was an independent predictive factor of DMFS. No significant difference was observed in the rates of grades 3-4 toxicities between both groups. Our results showed the addition of IC to CCRT was not superior to CCRT in unselected ESCC patients, while IC responders could benefit from this regime without increase in toxicities.

Dose Escalation Using Magnetic Resonance Guided High-Dose-Rate Endorectal Brachytherapy to Enhance Clinical Response after Neoadjuvant Radiotherapy in Rectal Adenocarcinoma

To assess the proportion of patients with rectal adenocarcinoma achieving clinical complete response after neoadjuvant chemoradiation (NACTRT) and MR guided endorectal brachytherapy boost (MR-ERBT) MATERIALS/METHODS: Patients with rectal cancers (T2-T4/N0-N+) treated with concurrent chemoradiotherapy (50Gy/25# with Capecitabine) between June-2017 to April-2022. Post RT, patients having residual non-circumferential lesions <8cm in length were administered escalated-dose MR-ERBT with Ir192 HDR source. A median dose of 12Gy (8-15Gy) in 3 (2-3) fractions at 3-5 day intervals was delivered using MR-ERBT after external radiation. Data on near complete/complete clinical response (nCR/cCR) rates, local regrowth rates and clinical outcome were collected for analysis. Of the 145 patients who received MR-ERBT, majority were staged as T3(78.7%) and N1-2 (77.5%) rectal cancers. Median tumor length was 4cm and 123 (85%) of the tumors were located in the lower rectum (0-5cm from anal verge). Seventy-six (52%) patients achieved cCR or nCR (37 cCR, 39 nCR) and were advised observation or watch and wait (WW) management. The 69 patients having partial response were advised surgery. The patients having nCR 16 (29%) underwent resection, of these 10 (62%) had pathological complete response (pCR). The patients with partial or poor response, 57 underwent resection and of these 11 (19%) had pCR, 12 patients refused surgery due to fear of permanent stoma and continued to be on follow up. Of the 79 patients undergoing resection, 36 (45.5%) had sphincter preserving surgeries. At the median follow up of 30 months, local regrowth was seen in 8 (10.5%) of patients on WW and 6 were surgically salvaged while other 2 had synchronous metastatic relapse. Thus, 56 (41%) achieved organ preservation and continued to be on WW management. Twelve (8,2%) patients developed distant metastasis in the entire cohort, 3 in the WW group and 9 in the resected group. There were no pelvic recurrences seen in the resected patients. The disease-free survival at 3 years were (96.1% vs 89% Observation vs. resected (p_0.05) respectively. The overall survival at 3 years were (93% vs 98% Observation vs. resected (p_0.44) respectively. Late rectal toxicity was observed in 16(11%) patients on observation CONCLUSION: Dose Escalated MR-EBRT is an effective and safe method to enhance complete clinical response, thus improving the rate of organ preservation for distal rectal cancers.

Retrospective evaluation of ceruminous gland tumors confined to the external ear canal of dogs and cats treated with biopsy and CO2 laser ablation.

Treatments currently available for ceruminous gland tumors include surgery and radiation therapy, which come with high financial costs and frequent complication and recurrence rates. To evaluate the treatment, response, complication, and recurrence of ceruminous gland tumors confirmed with biopsy and ablated using CO2 laser. Retrospective review of medical records from Iowa State Universityand the University of Illinois between January 1, 2016 and December 31, 2021. Electronic medical records were evaluated for a histopathologically confirmed ceruminous gland tumor via video-otoscopic aided biopsy and subsequent CO2 laser ablation. Signalment, tumor type, size, location within the ear canal, length of time tumor was present before presentation, advanced imaging, and follow-up including recurrence were assessed. Fourteen ceruminous gland adenomas (4 dogs, 10 cats) and 12 ceruminous gland adenocarcinomas (7 dogs, 5 cats) were identified. Bacterial otitis externa was present in 4/26 (15%) animals. Recurrence was identified in 1/14 (7%) ceruminous gland adenomas and 1/12 (8%) ceruminous gland adenocarcinomas. Video-otoscopic aided biopsy and CO2 laser ablation of ceruminous gland tumors in dogs and cats is a viable treatment option with low recurrence and complication rates with CO2 laser ablation.

MRI-based automated machine learning model for preoperative identification of variant histology in muscle-invasive bladder carcinoma.

It is essential yet highly challenging to preoperatively diagnose variant histologies such as urothelial carcinoma with squamous differentiation (UC w/SD) from pure UC in patients with muscle-invasive bladder carcinoma (MIBC), as their treatment strategy varies significantly. We developed a non-invasive automated machine learning (AutoML) model to preoperatively differentiate UC w/SD from pure UC in patients with MIBC. A total of 119 MIBC patients who underwent baseline bladder MRI were enrolled in this study, including 38 patients with UC w/SD and 81 patients with pure UC. These patients were randomly assigned to a training set or a test set (3:1). An AutoML model was built from the training set, using 13 selected radiomic features from T2-weighted imaging, semantic features (ADC values), and clinical features (tumor length, tumor stage, lymph node metastasis status), and subsequent ten-fold cross-validation was performed. A test set was used to validate the proposed model. The AUC of the ROC curve was then calculated for the model. This AutoML model enabled robust differentiation of UC w/SD and pure UC in patients with MIBC in both training set (ten-fold cross-validation AUC = 0.955, 95% confidence interval [CI]: 0.944-0.965) and test set (AUC = 0.932, 95% CI: 0.812-1.000). The presented AutoML model, that incorporates the radiomic, semantic, and clinical features from baseline MRI, could be useful for preoperative differentiation of UC w/SD and pure UC. This MRI-based automated machine learning (AutoML) study provides a non-invasive and low-cost preoperative prediction tool to identify the muscle-invasive bladder cancer patients with variant histology, which may serve as a useful tool for clinical decision-making. •It is important to preoperatively diagnose variant histology from urothelial carcinoma in patients with muscle-invasive bladder carcinoma (MIBC), as their treatment strategy varies significantly. •An automated machine learning (AutoML) model based on baseline bladder MRI can identify the variant histology (squamous differentiation) from urothelial carcinoma preoperatively in patients with MIBC. •The developed AutoML model is a non-invasive and low-cost preoperative prediction tool, which may be useful for clinical decision-making.

Patterns of the lymph node metastasis and the influencing factors in esophagogastric junction cancers.

A retrospective analysis of 214 cases of esophagogastric junction cancers (EGJCs) in Kunming, Yunnan Province, was conducted to investigate the lymph node metastasis (LNM) pattern for EGJCs and its associated risk factors (RFs), as well as the predictive value of common clinical metabolic indicators for it. The clinical data of 214 patients diagnosed with EGJCs by electronic gastroscope and postoperative pathology between 2013 and 2021at the First Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital, and the Second Affiliated Hospital of Kunming Medical University were retrospectively examined. Preoperative gastroscopy, imaging, biochemical data, and postoperative pathological findings analysis in EGJCs were statistically analyzed to determine the RFs of LNM. At presentation, 92.5% of EGJCs were progressive malignancies, including 68.2% LNMs, 79.5% abdominal lymph nodes (ALN), 20.1% mediastinal lymph nodes (MLN), and 27.1% distal metastases. The ratio of Siewert subtypes was approximately 2:11:7 (type I to type II to type III). In terms of age, disease duration at initial presentation, history, tumor length, pathological biopsy histology, degree of differentiation, depth of infiltration, LNM status, MLN metastasis, and surgical route, the differences between the three Siewert subgroups were statistically significant (p<0.05). Multifactor analysis revealed that the proportion of patients aged <65at the time of consultation was significantly more significant in Siewert II and Siewert III than in Siewert I. Significantly more patients than in Siewert I had <2 months of disease duration at the time of their first consultation. The proportion of patients with tumors <3 Cm in length was significantly higher than in Siewert I. For the RFs analysis of LNM, Siewert staging (type I and type II), depth of infiltration, and distant metastasis were the independent RFs for LNM. The depth of infiltration and family history of the tumor were the independent RFs for ALN metastasis, and the number of lymph nodes cleared in the abdominal and mediastinal regions was a protective factor for ALN metastasis. Siewert staging(type I and type II), infiltration depth, invasion of the esophagus by the tumor, tumor length, and distant metastasis were independent risk factors for MLN metastasis. Among the metabolic variables evaluated, BMI was an independent RF for LNM, fasting glucose was an independent RF for ALN metastasis, and triacylglycerol was a protective factor for MLN metastasis. EGJCs are frequently advanced at presentation, characterized by minimal differentiation and a high incidence of LNM. The Siewert subtype is concentrated near the stomach. Different Siewert subtypes exhibit distinct clinicopathological characteristics. LNM and MLN metastasis risk are considerably higher in type I tumors compared to types II and III. There is a strong correlation between LNM and MLN metastasis and distant metastasis in EGJCs, so Siewert I is more aggressive and associated with a worse prognosis. EGJCs have numerous RFs associated with LNM, and there are similarities and differences in the RFs affecting their LNM, ALN metastases, and MLN metastases, which are related to their unique anatomical features. There is a close relationship between metabolic factors and EGJCs with some predictive value.

430. MAPPING OF LYMPH NODE METASTASIS FROM ESCC AFTER NEOADJUVANT TREATMENT: A PROSPECTIVE ANALYSIS FROM A HIGH-VOLUME INSTITUTION IN CHINA

Abstract Objective The aim of the study was to describe the prevalence of lymph node metastases per lymph node station for esophageal squamous cell carcinoma (ESCC) after neoadjuvant treatment. Methods Clinicopathological variables of ESCC patients were retrieved from the prospective database of the Surgical Esophageal Cancer Patient Registry in West China Hospital, Sichuan University. Two-field lymphadenectomy was routinely performed and an extensive three-field lymphadenectomy was performed if cervical lymph nodes metastasis were suspected. Lymph node stations according to AJCC 8 were separately investigated. Percentage of patients with lymph node metastases was defined as number of patients with metastatic lymph nodes/number of patients with lymph node dissection of this station. Data is also separately analyzed according to pathological response of the primary tumor, pretreatment tumor length and tumor location. Results Between January 2019 and March 2023, 623 patients who underwent neoadjuvant therapy followed by transthoracic esophagectomy were enrolled (Table 1–1). Lymph node metastases were found in 215 patients (34.5%) and most frequently seen in lymph nodes along the right recurrent nerve (10.1%, 58/575), paracardial station (11.4%, 67/587) and lymph nodes along the left gastric artery (10.9%, 65/597). For patients with pretreatment tumor length &amp;gt; 4 cm and non-PCR of primary tumor, the metastatic rate of right lower cervical paratracheal lymph nodes is 10.9% (10/92) and 10.6% (11/104), respectively (Table 1–2). For patients with an upper thoracic tumor, metastatic lymph nodes were most frequently seen along the right recurrent nerve (14.2%, 8/56). For patients with a middle thoracic tumor, metastatic lymph nodes were most frequently seen in the right lower cervical paratracheal lymph nodes (10.3%, 8/78), paracardial lymph nodes (10.2%, 29/285) and lymph nodes along the left gastric artery (10.4%, 30/289). For patients with a lower thoracic tumor, metastatic lymph nodes were most frequently seen in paracardial station (14.2%, 35/247) and lymph nodes along the left gastric artery (13.1%, 33/252) (Table 1–3). Conclusion The study accurately identified the distribution of lymph node metastases from ESCC after neoadjuvant treatment, which may contribute to guide the optimal extent of lymphadenectomy in the surgical treatment of ESCC patients after neoadjuvant treatment.

278. MEDIASTINOSCOPIC ESOPHAGECTOMY WITH INTRAOPERATIVE NERVE MONITORING FOR ESOPHAGOGASTRIC JUNCTION ADENOCARCINOMA; A SINGLE-CENTER INITIAL EXPERIENCE

Abstract Background In recent years, adenocarcinoma of esophagogastric junction (EGJ) has been on the increase in Japan. Although laparoscopic resection by the transhiatal approach is commonly used, patients often have difficulty with mediastinal lymph node dissection and reconstruction after resection. Since 2020, we have been performing mediastinoscopic esophagectomy for EGJ adenocarcinoma patients with esophageal invasion exceeding 3 cm in length or with a large tumor diameter. We report on the short-term results of the surgery performed. Methods Of 15 patients with adenocarcinoma of the esophagogastric junction who underwent radical esophagectomy at our hospital during a 36-month period from January 2020 to December 2022, 5 patients underwent mediastinoscopic esophagectomy without thoracic incisions. Surgery consisted of mediastinoscopic and laparoscopic subtotal esophagectomy, mediastinal lymph node dissection, and posterior mediastinal gastric tube reconstruction with cervical anastomosis. In all cases, continuous left recurrent nerve monitoring was performed intraoperatively. Short-term surgical outcomes were evaluated in terms of age, gender, TNM classification, stage, preoperative complications, operation time, blood loss, tumor diameter, length of esophageal invasion, postoperative complications, and postoperative hospital stay. Results All five patients were male, with a mean age of 67.8 years. 4 of the 5 patients had preoperative complications. Tumor localization was Siewert classification type I in 4 patients and type II in 1. The average tumor length and esophageal invasion length was 44 ± 26 mm and 38 ± 11 mm respectively. The average operation time was 395 ± 29 minutes and blood loss was 38 ± 39 mL. Lymph node metastases was revealed in three patients. No postoperative anastomotic leakage or recurrent nerve palsy was observed. One patient developed postoperative aspiration pneumonia but was cured without reintubation. Conclusion Mediastinoscopic esophagectomy for EGJ adenocarcinoma was performed safely. RCTs conducted in Western countries reported that esophagectomy with cervical anastmosis is associated with higher rates of recurrent nerve palsy than esophagectomy by the transhiatal approach. The use of a mediastinoscope to visualize the recurrent nerve and the use of intraoperative nerve monitoring devices might reduce the frequency of recurrent nerve palsy.

479. TRANSTHORACIC VERSUS TRANSABDOMINAL SURGICAL APPROACH FOR SIEWERT TYPE II ESOPHAGOGASTRIC JUNCTIONAL ADENOCARCINOMAS—A PROPENSITY SCORE-MATCHED ANALYSIS

Abstract Background Esophagogastric junctional(EGJ) adenocarcinoma is a complex type of cancer that varies in etiology and disease pattern depending on the tumor level. There is increasing evidence on the need for different surgical approaches for different Siewert types. The optimal surgical approach for Siewert type II cancer remains controversial. This study aims to compare the oncological and surgical safety of transthoracic and transabdominal approaches for type II cancers. Methods The study included patients who underwent resection for Siewert type II adenocarcinomas from 2003–2020 in a single tertiary center using transthoracic (TT) and transabdominal (TA) approaches with macroscopic tumor clearance. The TT approach referred to Lewis-Tanner esophagogastrectomy, while the TA approach included total gastrectomy and proximal gastrectomy. Data from a prospectively-managed database were analyzed to compare postoperative morbidity and mortality rates, lymph node harvest, completeness of resection and overall survival between the two groups. Propensity score matching (PSM) was used in further analyses. Results Excluding R2 resections, there were 54 patients in the TT and 45 (proximal gastrectomy:23) in the TA groups. cT stages were comparable. In TT group, median tumor length was 6 cm (vs. 3 cm,p = 0.000), 18.5% with esophageal extension of &amp;gt;4 cm above EGJ;75.9% had nodal metastases (vs. 47.7%, p = 0.004);20.4% underwent neoadjuvant therapy (vs. 6.8%, p = 0.057). Anastomotic leak and cardiopulmonary complication rates, R0 resection rates, nodal yield and positive lymph node ratios were comparable. Proximal margin was involved in 15.9% for TA (vs. 5.6%, p = 0.092). Overall median survival times were similar (TT vs. TA: 42vs.65 months, p = 0.557). PSM yielded 33 patients per group. Only one in TT group had &amp;gt;4 cm esophageal involvement. Cardiac complication rate in TT group was 23.6%(vs. 3.5%, p = 0.024). Conclusion After correcting for selection bias, positive lymph node ratio, resection margin and overall survival did not differ for the TT and TA approaches. Resection by the TT approach is associated with more cardiac complications. For Siewert type II tumors with limited thoracic esophageal extension, the TA approach is safe and should be sufficient.

Predictive value of MRI-detected tumor deposits in locally advanced rectal cancer.

Although tumor deposits (TDs) are not the same as lymph nodes, the prognosis of patients with TDs is similar or worse than that of patients with metastatic lymph nodes. TDs are mostly assessed by the histology of samples after surgery, thus, not helpful for preoperative treatment strategies. The primary objective of this study was to detect TDs by MRI and evaluate its predictive value. A total of 114 patients with rectal cancer were retrospectively analyzed. Clinicopathological and MRI data mainly including MRI- detected TDs (mTDs), tumor border configuration (TBC) on MRI, MRI-detected extramural vascular invasion (mEMVI), MRI-detected lymph node metastasis (mLN), MRI T stage, MRI N stage, the range of rectal wall involved by the tumor, peritoneal reflection invasion, tumor length, tumor location, cord sign at the tumor edge, nodular protrusion at the tumor edge, maximal extramural depth and pathology-proven lymph node involvement (pLN) were evaluated. The correlation of MRI factors with postoperative distant metastasis (PDM) and pLN were analyzed by univariate analysis and multivariate logistic regression analysis, and nomograms were established based on the latter. The diagnostic efficiency was evaluated by the receiver operating characteristic curve (ROC) and area under the curve (AUC). A total of 38 cases of pLN, 13 of PDM and 17 of pathology-proven TDs (pTDs) were found. Ten cases of PDM and 22 cases of pLN in 30 mTDs cases were also found. Chi-square test showed that mTDs, mLN, TBC, mEMVI, MRI T stage, nodular protrusion, cord sign, maximal extramural depth and peritoneal reflection invasion were correlated with PDM and pLN (P<0.05). mTDs and peritoneal reflection invasion were independent risk factors for PDM (odds ratio: 10.15 and 8.77, P<0.05), mTDs and mLN were independent risk factors for pLN (odds ratio: 5.50 and 5.91, P<0.05), and Hosmer-Lemeshow test showed that the results of two models were not statistically significant, suggesting that the fit was good. On this basis, two nomograms for predicting PDM and pLN were confirmed by Bootstrap self-sampling, and the C-indices of the two nomograms were 0.837 and 0.817, respectively. The calibration curves and ROC curves of the two nomograms showed that the correlation between the predicted and the actual incidence of PDM and pLN was good. The DeLong test showed that the predictive efficiency of the nomogram in predicting pLN was better than that of mLN (P=0.0129). mTDs are a risk factor for PDM and lymph node metastasis. The two nomograms based on mTDs showed a good performance in predicting PDM and lymph node metastasis, possessing a certain clinical value.

Machine learning‑based prediction of survival prognosis in esophageal squamous cell carcinoma

The current prognostic tools for esophageal squamous cell carcinoma (ESCC) lack the necessary accuracy to facilitate individualized patient management strategies. To address this issue, this study was conducted to develop a machine learning (ML) prediction model for ESCC patients' survival management. Six ML approaches, including Rpart, Elastic Net, GBM, Random Forest, GLMboost, and the machine learning-extended CoxPH method, were employed to develop risk prediction models. The model was trained on a dataset of 1954 ESCC patients with 27 clinical features and validated on a dataset of 487 ESCC patients. The discriminative performance of the models was assessed using the concordance index (C-index). The best performing model was used for risk stratification and clinical evaluation. The study found that N stage, T stage, surgical margin, tumor grade, tumor length, sex, MPV, AST, FIB, and Mg are the important feature for ESCC patients’ survival. The machine learning-extended CoxPH model, Elastic Net, and Random Forest had similar performance in predicting the mortality risk of ESCC patients, and outperformed GBM, GLMboost, and Rpart. The risk scores derived from the CoxPH model effectively stratified ESCC patients into low-, intermediate-, and high-risk groups with distinctly different 3-year overall survival (OS) probabilities of 80.8%, 58.2%, and 29.5%, respectively. This risk stratification was also observed in the validation cohort. Furthermore, the risk model demonstrated greater discriminative ability and net benefit than the AJCC8th stage, suggesting its potential as a prognostic tool for predicting survival events and guiding clinical decision-making. The classical algorithm of the CoxPH method was also found to be sufficiently good for interpretive studies.

A multiple-time-scale comparative study for the added value of magnetic resonance imaging-based radiomics in predicting pathological complete response after neoadjuvant chemoradiotherapy in locally advanced rectal cancer.

Radiomics based on magnetic resonance imaging (MRI) shows potential for prediction of therapeutic effect to neoadjuvant chemoradiotherapy (nCRT) in locally advanced rectal cancer (LARC); however, thorough comparison between radiomics and traditional models is deficient. We aimed to construct multiple-time-scale (pretreatment, posttreatment, and combined) radiomic models to predict pathological complete response (pCR) and compare their utility to those of traditional clinical models. In this research, 165 LARC patients undergoing nCRT followed by surgery were enrolled retrospectively, which were divided into training and testing sets in the ratio of 7:3. Morphological features on pre- and posttreatment MRI, coupled with clinical data, were evaluated by univariable and multivariable logistic regression analysis for constructing clinical models. Radiomic parameters were derived from pre- and posttreatment T2- and diffusion-weighted images to develop the radiomic signatures. The clinical-radiomics models were then generated. All the models were developed in the training set and then tested in the testing set, the performance of which was assessed using the area under the receiver operating characteristic curve (AUC). Radiomic models were compared with the clinical models with the DeLong test. One hundred and sixty-five patients (median age, 55 years; age interquartile range, 47-62 years; 116 males) were enrolled in the study. The pretreatment maximum tumor length, posttreatment maximum tumor length, and magnetic resonance tumor regression grade were selected as independent predictors for pCR in the clinical models. In the testing set, the pre- and posttreatment and combined clinical models generated AUCs of 0.625, 0.842, and 0.842 for predicting pCR, respectively. The MRI-based radiomic models performed reasonably well in predicting pCR, but neither the pure radiomic signatures (AUCs, 0.734, 0.817, and 0.801 for the pre- and posttreatment and combined radiomic signatures, respectively) nor the clinical-radiomics models (AUCs, 0.734, 0.860, and 0.801 for the pre- and posttreatment and combined clinical-radiomics models, respectively) showed significant added value compared with the clinical models (all P > 0.05). The MRI-based radiomic models exhibited no definite added value compared with the clinical models for predicting pCR in LARC. Radiomic models can serve as ancillary tools for tailoring adequate treatment strategies.

Hypomethylation of DYRK4 in peripheral blood is associated with increased lung cancer risk.

Lung cancer (LC) is the leading cause of cancer-related deaths worldwide. It is urgent to identify new biomarkers for the early detection of LC. DNA methylation in peripheral blood has been reported to be associated with cancers. We conducted two independent case-control studies and a nested case-control study (168 LC cases and 167 controls in study Ⅰ, 677 LC cases and 833 controls in study Ⅱ, 147 precancers and 21 controls in the nested case-control study). The methylation levels of DYRK4 CpG sites were measured using mass spectrometry and their correlations with LC were analyzed by logistic regression and nonparametric tests. Bonferroni correction was used for the multiple comparisons. LC-related decreased DYRK4 methylation was discovered in Study I and validated in Study II (the odds ratios [ORs] for the lowest vs. highest quartile of all three DYRK4 CpG sites ranged from 1.64 to 2.09, all p < 0.001). Combining the two studies, hypomethylation of DYRK4 was observed in stage I cases (ORs per -10% methylation ranged from 1.16 to 1.38, all p < 5.9E-04), and could be enhanced by male gender (ORs ranged from 1.77 to 4.17 via interquartile analyses, all p < 0.017). Hypomethylation of DYRK4_A_CpG_2 was significantly correlated with tumor size, length, and stage (p = 0.034, 0.002, and 0.002, respectively) in LC cases. Our study disclosed the association between DYRK4 hypomethylation in peripheral blood and LC, suggesting the feasibility of blood-based DNA methylation as new biomarker for LC detection.

Development of a Nomogram to Predict Postoperative Peritoneal Metastasis of Colon Cancer.

The aim of this study was to determine the clinicopathological and radiological risk factors for postoperative peritoneal metastasis and develop a prediction model for the early detection of peritoneal metastasis in patients with colon cancer. We included 174 patients with colon cancer. The clinicopathological and radiological data were retrospectively analyzed. A Cox proportional hazards regression model was used to identify risk factors for postoperative peritoneal metastasis. Based on these risk factors, a nomogram was developed. At a median follow-up of 63 months, 43 (24.7%) patients developed peritoneal metastasis. Six independent risk factors (hazards ratio [95% confidence interval]) were identified for postoperative peritoneal metastasis: abdominopelvic fluid (2.12 [1.02-4.40]; P = 0.04), longer maximum tumor length (1.02 [1.00-1.03]; P = 0.02), pN1 (2.50 [1.13-5.56]; P = 0.02), pN2 (4.45 [1.77-11.17]; P = 0.02), nonadenocarcinoma (2.75 [1.18-6.38]; P = 0.02), and preoperative carcinoembryonic antigen levels ≥5 ng/mL (3.08 [1.50-6.30]; P < 0.01). A clinicopathological-radiological model was developed based on these factors. The model showed good discrimination (concordance index, 0.798 [0.723-0.876]; P < 0.001) and was well-calibrated. The developed clinicopathological-radiological nomogram may assist clinicians in identifying patients at high risk of postoperative peritoneal metastasis.