Optimal Resection Research Articles

2146 Combined Novel Endoscopic Techniques in Esophageal Carcinoma Management

INTRODUCTION: A variety of techniques are currently being investigated to provide optimal resection of submucosal tumors by endoscopy. Specifically, peroral endoscopic myotomy (POEM) is a form of natural orifice transluminal endoscopic procedure which was originally established as a minimally invasive technique to treat achalasia and esophageal motility disorders. Due to its success in treatment of esophageal motility disorders, certain Centers of Excellence for advanced endoscopy have expanded the use of POEM in combination with other advanced endoscopic techniques for treating esophageal cancers. In this case, we present a 69-year-old male with squamous cell cancer (SCC) in the lower third of the esophagus who was successfully treated using combined endoscopic submucosal dissection (ESD), submucosal tunneling, and POEM techniques. CASE DESCRIPTION/METHODS: A 69-year-old male with a medical history of 50-pack-year tobacco abuse, chronic alcohol use, and chronic pancreatitis was initially evaluated with EGD and EUS for anorexia, weight loss, and pancreatic cysts. Initial EGD required biopsies of nodular esophageal mucosa revealing underlying squamous cell carcinoma in situ. Repeat endoscopy 2 months later revealed a large tumor circumferentially involving 80% of the lumen in the lower esophagus. Subsequently, the patient received therapeutic intervention combining ESD and POEM techniques for tumor resection, prognostication, and symptom relief. Lesion borders were marked, and a circumferential incision was made around the lesion lifting it from the muscularis propria allowing for successfully mass excision. The submucosal dissection combined with circumferential tunneling technique allowed for complete resection of the tumor. The patient reported post-procedure symptomatic relief and was able to resume oral intake. DISCUSSION: POEM is a combination of the pre-existing endoscopic myotomy procedures in conjunction with endoscopic submucosal tunneling techniques. Although POEM is labor intensive, its application gives precision by granting access to the neoplasms without affecting deeper esophageal layers. This promising advance in gastrointestinal procedures compared to esophagectomy has shown in reported studies to offer a lower morbidity rate while providing similar cancer-free survival. Our case demonstrates successful treatment using POEM and adjunct endoscopic therapies in submucosal tunneling and submucosal tunneling endoscopic resection (STER) in the treatment of large circumferential esophageal cancer.

Quantification and Selection of Ictogenic Zones in Epilepsy Surgery.

Network models of brain dynamics provide valuable insight into the healthy functioning of the brain and how this breaks down in disease. A pertinent example is the use of network models to understand seizure generation (ictogenesis) in epilepsy. Recently, computational models have emerged to aid our understanding of seizures and to predict the outcome of surgical perturbations to brain networks. Such approaches provide the opportunity to quantify the effect of removing regions of tissue from brain networks and thereby search for the optimal resection strategy. Here, we use computational models to elucidate how sets of nodes contribute to the ictogenicity of networks. In small networks we fully elucidate the ictogenicity of all possible sets of nodes and demonstrate that the distribution of ictogenicity across sets depends on network topology. However, the full elucidation is a combinatorial problem that becomes intractable for large networks. Therefore, we combine computational models with a genetic algorithm to search for minimal sets of nodes that contribute significantly to ictogenesis. We demonstrate the potential applicability of these methods in practice by identifying optimal sets of nodes to resect in networks derived from 20 individuals who underwent resective surgery for epilepsy. We show that they have the potential to aid epilepsy surgery by suggesting alternative resection sites as well as facilitating the avoidance of brain regions that should not be resected.

P09.01 case series: meningioma in young adult male

Abstract BACKGROUND Intracranial meningiomas are most common among patients in their fifth to seventh decade of life, typically found in older women. Meningiomas are rare in children and young adults; they represent 1–3% of all intracranial tumors in individuals up to age 20 years and 13.5% of intracranial tumors in the 20–34 age group. Meningioma in young adult male is a rare finding. Management of meningioma is similar between young or older patient. The prognosis is depent on the histology finding and type of resection. This case series was made to report an uncommon case including clinical characteristic and management of meningioma in young adult male. MATERIAL AND METHODS We reported 2 cases of meningioma in young adult male. The first patient was hospitalized on 2016 and diagnosed with atypical meningioma (WHO grade II). The second patient was hospitalized on 2018 and diagnosed with trantitional meningioma (WHO grade I). RESULTS First case: 23 y.o male was hospitalized because of severe headache. His physical exam showed weakness of his left side of the body. There was diplopia that significant for bilateral six nerves palsy. Funduscopy examination revealed papil edema in both eyes correlated with his complained of blurry visions. There was no cranial irradiation from his past medical history. Second case, a male 22 y.o was because of decreased of visual acquity progressively since two month before. There was history of throbbing headache in his left head with mild to moderate intensity. On his neurological examination, there was mild weakness in his right body side. Visual acquity on his right and left eyes were 1/300 and 1/60. Bilateral papil edema was found in funduscopy examination. In his past medical history, there was no history of cranial iradiation. Both cases showed similar initial symptoms consist of headache and others neurological deficit. Radiological examination was performed with result leading to meningioma in convexity area in both cases. Craniotomy tumor removal with gross total resection as simpson grade 2 was achieved in both patients. In the second case pre-operative embolization was performed in order to achieve optimal resection. Histopathology examination confirmed as atypical (WHO grade II) in the first case and trantitional Meningioma (WHO grade I) in second case. Follow up imaging post operation showed no residual mass lesion in both patients. There were no further management in these patients. Both of patients showed improvement in their neurologic function and able to activity without restriction in daily living. Serial imaging examination is planned to observe reccurence of the tumor. CONCLUSION Clinical presentation and management of meningioma in these patients are similar as meningioma commonly. Both of patients showed clinical improvement after craniotomy tumor removal succesfully.

Robotic assisted laparoscopic resection of anterior adenomyoma

Video Objective This video demonstrates a unique technique of anterior adenomyoma resection and repair of the defect laparoscopically. Setting Our patient is a 40 yo G 3P0020 with secondary infertility and had multiple failed euploid frozen embryo transfers. She was diagnosed to have an anterior adenomyoma and decision was taken to excise the adenomyoma to optimize the fertility outcome. Interventions We performed a robotic assisted laparoscopic anterior adenomyomectomy where we excised the adenomyoma leaving approximately 1 cm of myometrium to the endometrium and serosa and then close d the defect by the overlap flap technique. Conclusion We describe an unique technique for optimal adenomyoma resection and then the effective way to close the uterine defect. This technique is easily adaptable and reproducible. This repair technique achieves good myometrial thickness after closure that reduces the chance of uterine rupture and the addition of extra suture layer decreases the chance of hematoma formation.

Protocol for the VAL-MAP 2.0 trial: a multicentre, single-arm, phase III trial to evaluate the effectiveness of virtual-assisted lung mapping by bronchoscopic dye injection and microcoil implementation in patients with small pulmonary nodules in Japan

IntroductionTumour localisation is important for successful resection of lung nodules with optimal resection margins in sublobar resection. Virtual-assisted bronchoscopic localisation technique combined with dye marking and microcoil placement (VAL-MAP 2.0)...

Changing concepts in presurgical assessment for epilepsy surgery.

Candidates for epilepsy surgery must undergo presurgical evaluation to establish whether and how surgical treatment can stop seizures without causing neurological deficits. Various techniques, including MRI, PET, single-photon emission CT, video-EEG, magnetoencephalography and invasive EEG, aim to identify the diseased brain tissue and the involved network. Recent technical and methodological developments, encompassing both advances inexisting techniques and new combinations of technologies, are enhancing the ability to define the optimal resection strategy. Multimodal interpretation and predictive computer models are expected to aid surgical planning and patient counselling, and multimodal intraoperative guidance is likely to increase surgical precision. In this Review, we discuss howthe knowledge derived from these new approaches is challenging our way of thinking about surgery to stop focal seizures. In particular, we highlight the importance of looking beyond the EEG seizure onset zone and considering focal epilepsy as a brain network disease in which long-range connections need to be taken into account. We also explore how new diagnostic techniques are revealing essential information in the brain that was previously hidden from view.

Novel diffusion tractography methodology using Kalman filter prediction to improve preoperative benefit-risk analysis in pediatric epilepsy surgery.

In this study the authors investigated the clinical reliability of diffusion weighted imaging maximum a posteriori probability (DWI-MAP) analysis with Kalman filter prediction in pediatric epilepsy surgery. This approach can yield a suggested resection margin as a dynamic variable based on preoperative DWI-MAP pathways. The authors sought to determine how well the suggested margin would have maximized occurrence of postoperative seizure freedom (benefit) and minimized occurrence of postoperative neurological deficits (risk). The study included 77 pediatric patients with drug-resistant focal epilepsy (age 10.0 ± 4.9 years) who underwent resection of their presumed epileptogenic zone. In preoperative DWI tractography from the resected hemisphere, 9 axonal pathways, Ci=1-9, were identified using DWI-MAP as follows: C1-3 supporting face, hand, and leg motor areas; C4 connecting Broca's and Wernicke's areas; C5-8 connecting Broca's, Wernicke's, parietal, and premotor areas; and C9 connecting the occipital lobe and lateral geniculate nucleus. For each Ci, the resection margin, di, was measured by the minimal Euclidean distance between the voxels of Ci and the resection boundary determined by spatially coregistered postoperative MRI. If Ci was resected, di was assumed to be negative (calculated as -1 × average Euclidean distance between every voxel inside the resected Ci volume, ri). Kalman filter prediction was then used to estimate an optimal resection margin, d*i, to balance benefit and risk by approximating the relationship between di and ri. Finally, the authors defined the preservation zone of Ci that can balance the probability of benefit and risk by expanding the cortical area of Ci up to d*i on the 3D cortical surface. In the whole group (n = 77), nonresection of the preoperative preservation zone (i.e., actual resection margin d*i greater than the Kalman filter-defined d*i) accurately predicted the absence of postoperative motor (d*1-3: 0.93 at seizure-free probability of 0.80), language (d*4-8: 0.91 at seizure-free probability of 0.81), and visual deficits (d*9: 0.90 at seizure-free probability of 0.75), suggesting that the preservation of preoperative Ci within d*i supports a balance between postoperative functional deficit and seizure freedom. The subsequent subgroup analyses found that preservation of preoperative Ci =1-4,9 within d*i =1-4,9 may provide accurate deficit predictions independent of age and seizure frequency, suggesting that the DWI-based surgical margin can be effective for surgical planning even in young children and across a range of epilepsy severity. Integrating DWI-MAP analysis with Kalman filter prediction may help guide epilepsy surgery by visualizing the margins of the eloquent white matter pathways to be preserved.

Semi-Quantitative Comparison of Infrared Thermography with Indocyanine Green Imaging in Porcine Intestinal Resection

BackgroundThe quality of intestinal blood supply is extremely important for healing of intestinal anastomoses. During the surgery the blood supply of the intestine may appear sufficient even though the microperfusion is not fully adequate. The degree of blood supply of remaining intestinal segment and the positioning of the resection margins is estimated subjectively by the surgeon's experience or objectively by means of indocyanine green fluorescence imaging. The subject of our study is the evaluation of the infrared thermal imaging as another supportive non-invasive imaging method in assessment of intestinal blood supply, and to compare surgeon's decisions of the position of resection line with information obtained by infrared thermal imaging and by indocyanine green fluorescence imaging. MethodsA pilot study on thermal imaging measurements was done in a porcine model. The infrared thermocamera Workswell WIC 640 was used in our study. The thermal imaging was correlated with the indocyanine green imaging method ICG NOVADAQ and with surgeon's subjective expert decisions of the places of resection lines. Fifteen monitored resections were performed on three experimental porcine models. ResultsBased on the data evaluated, experience of the surgical team and the post-operative conditions of the porcine models, we conclude that the thermal imaging is a useful tool for determination of the optimal intestinal resection margins, and thus contributes to lowering anastomotic complications rate in colorectal surgery. The results show relatively high consistency between the used imaging techniques. Both methods showed ischemic regions of the intestine at a comparable level. The IRT methods showed even a slightly higher match with the surgeon's rating. ConclusionBased on experiments, the infrared thermography can be considered as one of complementary imaging methods suitable for use during anastomosis surgery. The sensitivity and versatility of the infrared thermography method was demonstrated. There was confirmed agreement in obtained information about the position of area with maximal blood insufficiency obtained by IRT with the information obtained by using the ICG method.

Performance of a machine learning-based decision model to help clinicians decide the extent of lymphadenectomy (D1 vs. D2) in gastric cancer before surgical resection

Controversy still exists on the optimal surgical resection for potentially curable gastric cancer (GC). Use of radiologic evaluation and machine learning algorithms might predict extent of lymphadenectomy to limit unnecessary surgical treatment. We purposed to design a machine learning-based clinical decision-support model for predicting extent of lymphadenectomy (D1 vs. D2) in local advanced GC. Clinicoradiologic features available from routine clinical assignments in 557 patients with GCs were retrospectively interpreted by an expert panel blinded to all histopathologic information. All patients underwent surgery using standard D2 resection. Decision models were developed with a logistic regression (LR), support vector machine (SVM) and auto-encoder (AE) algorithm in 371 training and tested in 186 test data, respectively. The primary end point was to measure diagnostic performance of decision model and a Japanese gastric cancer treatment guideline version 4th (JPN 4th) criteria for discriminate D1 (pT1 + pN0) versus D2 (≥ pT1 + ≥ pN1) lymphadenectomy. The decision model with AE analysis produced highest area under ROC curve (train: 0.965, 95% confidence interval (CI) 0.948-0.978; test: 0.946, 95% CI 0.925-0.978), followed by SVM (train: 0.925, 95% CI 0.902-0.944; test: 0.942, 95% CI 0.922-0.973) and LR (train: 0.886, 95% CI 0.858-0.910; test: 0.891, 95% CI 0.891-0.952). By this improvement, overtreatment was reduced from 21.7% (121/557) by treat-all pattern, to 15.1% (84/557) by JPN 4th criteria, and to 0.7-0.9% (4-5/557) by the new approach. The decision model with machine learning analysis demonstrates high accuracy for identifying patients who are candidates for D1 versus D2 resection. Its approximate 14-20% improvements in overtreatment compared to treat-all pattern and JPN 4th criteria potentially increase the number of patients with local advanced GCs who can safely avoid unnecessary lymphadenectomy.

Effect of Resection Distance from Pylorus on Weight Loss Outcomes in Laparoscopic Sleeve Gastrectomy.

Despite the established efficacy and safety of laparoscopic sleeve gastrectomy (LSG), controversy still exists on optimal operative technique, the resection distance from pylorus (DP) being among the most controversial issues. This study aimed to examine the effect of resection distance from pylorus on % excess weight loss (EWL) during postoperative period, in patients who underwent LSG for morbid obesity. A total of 390 patients who underwent laparoscopic sleeve gastrectomy for morbid obesity were included in this retrospective study. Patients were allocated into one of the two groups based on the distance between antrum resection margin and pylorus: group A, ≤ 3cm and group B, > 3cm. Follow-up data for %EWS and nausea/vomiting as well as demographical and perioperative data were retrospectively reviewed and logistic regression analysis was done. Follow-up data up to 12months were available for all patients, whereas 199 patients had follow-up data at 24months. Shorter distance from pylorus was associated with higher %EWL throughout the treatment period (p < 0.001), evident from the first postoperative month (p = 0.013 for the first month, p < 0.001 for all other time points). The benefit extended up to 24months in ≤ 3cm group. However, nausea/vomiting was more frequent in the ≤ 3cm group only at 1-month visit (15% vs. 4%, p< 0.001). In multivariate evaluations, while %EWL variable was taken as a dependent variable, time variable with DP × time interaction was statistically significant in the model. Our findings indicate that a short distance between resection margin and pylorus is associated with better and sustained %EWL in LSG. However, these patients seem to be more prone to nausea and vomiting in the early postoperative period. Further prospective large studies would help to define an optimal resection distance.

Factors associated with one-year mortality after debulking surgery in older women with ovarian cancer.

e17069 Background: The objective of this study was to assess the factors associated with one-year mortality following cytoreductive surgery among women ≥65 years with epithelial ovarian cancer (EOC). Methods: Since 2011, patients aged 65 and older with advanced EOC, who underwent cytoreductive surgery within two months of initial visit, and had at least one year of follow up were included. Mortality data was retrieved from social security death index. Independent variables of interest were age, American Society of Anesthesiologist Physical Status (ASA-PS) classification, preoperative albumin, Memorial Sloan Kettering Frailty Index (MSK-FI), procedure time, intraoperative blood loss, 30-day minor and major adverse events, 30-day readmission and emergency room visits, stage, rate of suboptimal surgery, and receipt of neoadjuvant chemotherapy (NACT). Univariate analysis was performed to assess relationship between these variables and one-year mortality. Results: In total, 263 women (median age 70, range 65-88), of whom 26% had stage IV disease and 5% suboptimal surgery, were included. One-year mortality was 6.5% (n = 17), with six patients dying within six months. On univariate analysis, patients who died within the first year differed from those who were alive at one year in terms of length of stay (13 vs 9 days, p = 0.01), pre-operative albumin (3.8 vs 4.1, p = 0.01), major adverse events (29.4% vs. 12.2%, p = 0.04), and receipt of NACT (33.3% vs. 14.7%, p = 0.05). Patients who died within one year had an insignificant difference in MSK-FI (1.4 vs. 0.8, p = 0.08), and pre-operative hemoglobin (11.4 vs. 12.1, p = 0.06), as well as no difference in in age, ASA-PS, stage, procedure time, blood loss, minor adverse events, readmission and emergency room visits. Patients with suboptimal surgery did not have significantly higher one-year mortality rates, compared to those with optimal resection (11.8% vs. 4.5%, p = 0.5). Conclusions: Cytoreductive surgery in the selected group of older women is safe. In this cohort, age and ASA PS were not among factors associated with one year mortality. More robust risk stratification for this cohort is needed.

Advanced Epithelial Ovarian Cancer: Do More Options Mean Greater Benefits?

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice. A healthy 51-year-old woman presented with increasing abdominal and pelvic pain. Computed tomography imaging of the abdomen and pelvis showed an 11.6-cm pelvic mass, retroperitoneal lymphadenopathy, right hydronephrosis, and mesenteric tumor deposits ( Fig 1A ). A serum CA-125 was elevated at 1,149 U/mL. She underwent primary surgical cytoreduction including hysterectomy, bilateral salpingo-oophorectomy, appendectomy, resection of pelvic tumor, omentectomy, and low anterior resection with colorectal anastomosis. Intraoperatively, she was noted to have bilateral ovarian masses, pelvic and para-aortic lymphadenopathy, and a 4-cm omental tumor; in addition, both the uterus and rectosigmoid colon had adherent tumor deposits. All gross tumor was resected during the procedure. Final pathology confirmed high-grade serous carcinoma of ovarian origin ( Fig 1B ) that was determined to be stage IIIC as a result of upper abdominal involvement with greater than 2-cm tumor deposits, as well as retroperitoneal lymph node involvement. She underwent germline genetic testing, which did not identify a mutation in the BRCA1, BRCA2, BRIP1, RAD51C, or RAD51D genes. She presented for adjuvant chemotherapy after an optimal (R0) resection.

Long term surgical results of 154 petroclival meningiomas: A retrospective multicenter study

BackgroundOutcomes of petroclival meningiomas (PCM) (morbidity, permanent cranial nerves deficit, tumor removal and recurrence) are inconsistent in the literature, making it a challenge to predict surgical morbidity. MethodsA multicenter study of patients with PCMs larger than 2.5cm between 1984 and 2017 was conducted. The authors retrospectively reviewed the patients’ medical records, imaging studies and pathology reports to analyze presentation, surgical approach, neurological outcomes, complications, recurrence rates and predictive factors. ResultsThere were 154 patients. The follow-up was 76.8 months on average (range 8–380 months). Gross total resection (GTR) was achieved in 40 (26.0%) patients, subtotal resection (STR) in 101 (65.6%), and partial resection in 13 (8.3%). Six (2.6%) perioperative deaths occurred. The 5-year, 10-year and 15-year progression-free survival (PFS) of GTR and STR with radiation therapy (RT) was similar (100%, 90% and 75%). PFS of STR without adjuvant radiation was associated with progression in 71%, 51% and 31%, respectively. Anterior petrosectomy and combined petrosectomy were associated with higher postoperative CN V and CN VI deficits compared to the retrosigmoid approach. The latter had a significantly higher risk of CN VII, CN VIII and LCN deficit. Temporal lobe dysfunction (seizure and aphasia) were significantly associated with the anterior petrosectomy approach. ConclusionsOur study shows that optimal subtotal resection of PCMs associated with postoperative RT or stereotactic radiosurgery results in long-term tumor control to equivalent radical surgery. Case selection and appropriate intraoperative judgement are required to reduce the morbidity.

Receptor tyrosine kinase gene amplification is predictive of intraoperative seizures during glioma resection with functional mapping.

Intraoperative seizures during craniotomy with functional mapping is a common complication that impedes optimal tumor resection and results in significant morbidity. The relationship between genetic mutations in gliomas and the incidence of intraoperative seizures has not been well characterized. Here, the authors performed a retrospective study of patients treated at their institution over the last 12 years to determine whether molecular data can be used to predict the incidence of this complication. The authors queried their institutional database for patients with brain tumors who underwent resection with intraoperative functional mapping between 2005 and 2017. Basic clinicopathological characteristics, including the status of the following genes, were recorded: IDH1/2, PIK3CA, BRAF, KRAS, AKT1, EGFR, PDGFRA, MET, MGMT, and 1p/19q. Relationships between gene alterations and intraoperative seizures were evaluated using chi-square and two-sample t-test univariate analysis. When considering multiple predictive factors, a logistic multivariate approach was taken. Overall, 416 patients met criteria for inclusion; of these patients, 98 (24%) experienced an intraoperative seizure. Patients with a history of preoperative seizure and those treated with antiepileptic drugs prior to surgery were less likely to have intraoperative seizures (history: OR 0.61 [95% CI 0.38-0.96], chi-square = 4.65, p = 0.03; AED load: OR 0.46 [95% CI 0.26-0.80], chi-square = 7.64, p = 0.01). In a univariate analysis of genetic markers, amplification of genes encoding receptor tyrosine kinases (RTKs) was specifically identified as a positive predictor of seizures (OR 5.47 [95% CI 1.22-24.47], chi-square = 5.98, p = 0.01). In multivariate analyses considering RTK status, AED use, and either 2007 WHO tumor grade or modern 2016 WHO tumor groups, the authors found that amplification of the RTK proto-oncogene, MET, was most predictive of intraoperative seizure (p < 0.05). This study describes a previously unreported association between genetic alterations in RTKs and the occurrence of intraoperative seizures during glioma resection with functional mapping. Future models estimating intraoperative seizure risk may be enhanced by inclusion of genetic criteria.

Predictive Factors of Early Postoperative and Long-Term Facial Nerve Function After Large Vestibular Schwannoma Surgery

The preservation of acceptable facial nerve (FN) function after surgery is the key concern for most patients with vestibular schwannomas (VS). To assess predictive factors of early postoperative and long-term FN function in patients harboring large VS operated with a FN-sparing technique. Single-center retrospective cohort study with 169 consecutive large VS operated on between January 2003 and May 2015. Clinical, radiologic, and intraoperative factors were assessed according to FN function. At last follow-up examination, among the 145 patients without preoperative FN palsy, FN function was good (House-Brackmann [HB] grades I or II) in 84% and moderate (HB grade III) in 15% of patients. Only 1 patient presented with poor HB grade IV function. Multivariate logistic regression model showed the mean preoperative VS extrameatal diameter as being an independent predictor of an unfavorable initial FN outcome (odds ratio [OR], 1.062; P= 0.038). Surgical anatomic preservation of the cochlear nerve was associated with better FN outcomes (OR, 0.237; P= 0.012). A history of previous surgery seemed to be related to long-term impaired FN function (OR, 71.405; P=0.042), as well as early postoperative FN function (OR, 19.068; P= 0.000). No correlation was found between a history of previous Gamma Knife surgery treatment (P=0.225) or the extent of resection (P= 0.438) and impaired FN outcomes. History of previous surgery was identified as an unfavorable predictive recovery factor of impaired postoperative FN function (P= 0.034). As long as the extent of resection or additional Gamma Knife surgery have not been identified as predictive risk factors of postoperative FN palsy, we suggest that optimal resection is the main option for patients harboring large VS.

What Is the Best Operation for Proximal Gastric Cancer and Distal Esophageal Cancer?

Cancer of the gastroesophageal junction (GEJ) is increasing in incidence, likely as a result of rising obesity and gastroesophageal reflux disease rates. The tumors that arise here share features of esophageal and gastric cancer, and are classified based on their location in relationship to the GEJ. The definition of the GEJ itself, as well as optimal resection strategy, extent of lymph node dissection, resection margin length, and reconstruction methods are still very much a subject of debate. This article summarizes the available evidence on this topic, and highlights specific areas for further research.

Concepts and techniques: how to determine and identify the appropriate target segment in anatomical pulmonary segmentectomy?

Anatomical segmentectomy is gathering increasing interest among thoracic surgeons because of increased detection of pulmonary nodules with ground-glass opacity (GGO) as well as an increase in the number of compromised patients. Accurate determination of intersegmental planes is a challenge in anatomical segmentectomy, and multiple methods have been proposed including developing inflation/deflation lines and injecting indocyanine green either intravenously or intrabronchially. Considering resection margins, adding a localization technique to conventional methods, or conducting virtual-assisted lung mapping (bronchoscopic multi-spot dye marking) may be an optional approach for optimal anatomical segmentectomy to identify intersegmental planes and obtain adequate resection margins. To determine optimal resection lines in anatomical segmentectomy, surgeons must also consider oncological validity such as venous and lymph drainage, resection margins, and lung anatomy to avoid complications such as venous congestion, infarction, and air leakage. Although anatomical segmentectomy is an attractive approach to resect small early-stage lung cancer and some metastatic lung tumors, caution is needed to optimally perform this technically demanding surgery.

Optimal sublobar resection for c-stage I non-small cell lung cancer: significance of margin distance to tumor size ratio and margin cytology (Supplementary analysis of KLSG-0801): complete republication.

Sublobar resection for lung cancer is associated with a higher risk of recurrence than that of lobectomy; we evaluated the factors considered to be predictors of recurrence. By analyzing multicenter prospective studies of sublobar resection for patients with c-stage I non-small lung cancer who were unable to undergo lobectomy (KLSG-0801), we investigated the relationship between (1) tumor location (TL) and margin distance from the stump (MD), (2) the MD/tumor size (TS) ratio and prognosis, (3) and the margin cytology (MC) and prognosis. The correlation between TS and MD was statistically significant in cases of easily resectable regions defined by Lewis' classification (n = 18). However, there was no correlation in difficult-to-resect regions (n = 14). Among cases of recurrence, the MD/TS ratio was less than 1. The 3-year survival rate was 100% for patients with MD/TS > 1 (n = 12), 59.7% for patients with MD/TS ≤ 1 (n = 20) (p = 0.06), 88.1% in cases of negative MC (n = 18), and 20% in cases of positive MC (n = 5) (p = 0.001). Cases with positive MC had a significantly worse prognosis than those with negative MC. It may be difficult to secure an MD greater than the TS in a difficult-to-resect region according to Lewis' classification.

In Reply to the Letter to the Editor Regarding “Adjunctive Gamma Knife Surgery or Wait and Scan Policy After Optimal Resection of Large Vestibular Schwannomas: Clinical and Radiologic Outcomes”

The use of image guidance (IG) in neurosurgery is ubiquitous, even though evidence from patient outcome data has remained limited to smaller, mostly observational, studies. Ommaya reservoir insertion (ORI) has been available as a treatment option for targeted intraventricular pharmacotherapy since the 1960s, far preceding the modern neuronavigation era. We conducted a systematic review and meta-analysis investigating the impact of IG on surgical outcome from ORI.A systematic database search of MEDLINE and EMBASE was performed to identify studies on operative outcomes from ORI. Only studies reporting patient demographics and perioperative outcomes (hemorrhage, infection, malposition, malfunction, and mortality) were included. Study quality was assessed via MINORS criteria.Of the 3560 records screened, 43 studies met study inclusion criteria, for a total of 1995 ORI procedures. Pooled rates of outcome for IG compared with non-IG were 6.4% versus 14.1% for overall complications; 2.0% compared with 2.8% for catheter malfunction; 2.3% compared with 3.3% for catheter malposition; 0.7% compared with 4.5% for early infection; and 0.6% compared with 1.4% for mortality. Postoperative hemorrhage was increased at 3.4% compared with 2.4%. Subgroup analysis revealed a difference in early infection rate between frameless and frame-based IG at 0.0% versus 1.9%. Meta-regression revealed a relationship between publication date and all operative outcomes except for catheter malposition and hemorrhage.This study offers a historical context on the evolution of the practice of ORI and comprises the largest observational analysis of operative outcomes providing objective support for the use of IG in neurosurgery.

Letter to the Editor Regarding “Adjunctive Gamma Knife Surgery or Wait and Scan Policy After Optimal Resection of Large Vestibular Schwannomas: Clinical and Radiologic Outcomes”

Letter to the Editor Regarding “Adjunctive Gamma Knife Surgery or Wait and Scan Policy After Optimal Resection of Large Vestibular Schwannomas: Clinical and Radiologic Outcomes”