Medical Microrobots.

Scientists around the world have long aimed to produce miniature robots that can be controlled inside the human body to aid doctors in identifying and treating diseases. Such microrobots hold the potential to access hard-to-reach areas of the body through the natural lumina. Wireless access has the potential to overcome drawbacks of systemic therapy, as well as to enable completely new minimally invasive procedures. The aim of this review is fourfold: first, to provide a collection of valuable anatomical and physiological information on the target working environments together with engineering tools for the design of medical microrobots; second, to provide a comprehensive updated survey of the technological state of the art in relevant classes of medical microrobots; third, to analyze currently available tracking and closed-loop control strategies compatible with the in-body environment; and fourth, to explore the challenges still in place, to steer and inspire future research.

Shape-constrained deformable brain segmentation: Methods and quantitative validation.

MRI-guided neuro interventions require rapid, accurate, and reproducible segmentation of anatomical brain structures for identification of targets during surgical procedures and post-surgical evaluation of intervention efficiency. Segmentation algorithms must be validated and cleared for clinical use. This work introduces a methodology for shape-constrained deformable brain segmentation, describes the quantitative validation used for its clinical clearance, and presents a comparison with manual expert segmentation and FreeSurfer, an open source software for neuroimaging data analysis. ClearPoint Maestro is software for fully-automatic brain segmentation from T1-weighted MRI that combines a shape-constrained deformable brain model with voxel-wise tissue segmentation within the cerebral hemispheres and the cerebellum. The performance of the segmentation was validated in terms of accuracy and reproducibility. Segmentation accuracy was evaluated with respect to training data and independently traced ground truth. Segmentation reproducibility was quantified and compared with manual expert segmentation and FreeSurfer. Quantitative reproducibility analysis indicates superior performance compared to both manual expert segmentation and FreeSurfer. The shape-constrained methodology results in accurate and highly reproducible segmentation. Inherent point based-correspondence provides consistent target identification ideal for MRI-guided neuro interventions.

Neoadjuvant nivolumab plus chemotherapy in resectable non-small-cell lung cancer in Japanese patients from CheckMate 816.

In the open-label, phase III CheckMate 816 study (NCT02998528), neoadjuvant nivolumab plus chemotherapy demonstrated statistically significant improvements in event-free survival (EFS) and pathological complete response (pCR) versus chemotherapy alone in patients with resectable non-small-cell lung cancer (NSCLC). Here we report efficacy and safety outcomes in the Japanese subpopulation. Patients with stage IB-IIIA, resectable NSCLC were randomized 1:1 to nivolumab plus chemotherapy or chemotherapy alone for three cycles before undergoing definitive surgery within 6 weeks of completing neoadjuvant treatment. The primary end-points (EFS and pCR) and safety were assessed in patients enrolled at 16 centers in Japan. Of the Japanese patients randomized, 93.9% (31/33) in the nivolumab plus chemotherapy arm and 82.9% (29/35) in the chemotherapy arm underwent surgery. At 21.5 months' minimum follow-up, median EFS was 30.6 months (95% confidence interval [CI], 16.8-not reached [NR]) with nivolumab plus chemotherapy versus 19.6 months (95% CI, 8.5-NR) with chemotherapy; hazard ratio, 0.60 (95% CI, 0.30-1.24). The pCR rate was 30.3% (95% CI, 15.6-48.7) versus 5.7% (95% CI, 0.7-19.2), respectively; odds ratio, 7.17 (95% CI, 1.44-35.85). Grade 3/4 treatment-related adverse events were reported in 59.4% versus 42.9% of patients, respectively, with no new safety signals identified. Neoadjuvant nivolumab plus chemotherapy resulted in longer EFS and a higher pCR rate versus chemotherapy alone in Japanese patients, consistent with findings in the global population. These data support nivolumab plus chemotherapy as a neoadjuvant treatment option in Japanese patients with resectable NSCLC.

Minimally invasive surgical therapies for benign prostatic hyperplasia in the geriatric population: A systematic review.

BACKGROUND: Geriatric patients, prone to adverse events (AEs) and low compliance with drugs, may benefit from minimally invasive surgical therapies (MISTs) for managing benign prostatic hyperplasia (BPH). We evaluated the efficacy, safety, and procedural characteristics of MISTs in geriatric patients with BPH. METHODS: PubMed/MEDLINE database was systematically searched for relevant articles through October 1, 2023. Eligible studies focused on geriatric patients (≥65 years) with BPH who were treated with MISTs and evaluated follow-up surgical, micturition, and/or sexual outcomes. Studies were included if there was separate reporting for age subgroups ≥65 years, or if the mean age minus standard deviation was ≥65 years, or if the first quartile was ≥65 years. RESULTS: Out of 292 screened studies, 32 (N = 3972 patients) met inclusion criteria and assessed prostatic artery embolization (PAE), Rezum, GreenLight, holmium laser enucleation of the prostate (HoLEP), thulium laser enucleation of the prostate (ThuLEP), diode laser enucleation of the prostate (DiLEP), and Aquablation. Except for Rezum, all MISTs required a planned overnight stay. While PAE and Rezum could be performed under local anesthesia, the other MISTs needed general or spinal anesthesia. Postoperative catheterization duration was longest for PAE (median 14 days) and Rezum (21 days) and shortest for GreenLight (1.9 days). At 12 months postoperatively, all MISTs exhibited significant percent changes in International Prostate Symptom Score (median -69.9%) and quality of life (median -72.5%). Clavien-Dindo Grade 1 AEs ranged widely, with PAE (5.8%-36.8%), Rezum (0%-62.1%), and GreenLight (0%-67.6%) having the largest range, and HoLEP (0%-9.5%), ThuLEP (2%-6.9%), and DiLEP (5%-17.5%) having the smallest. PAE, Rezum, DiLEP, and Aquablation reported no significant changes in the International Index of Erectile Function. CONCLUSIONS: Although all the MISTs reviewed in this study effectively treat BPH in geriatric patients, differences in procedural characteristics and safety profiles across MISTs were considerable. Physicians should use shared decision-making processes, considering risks and patient characteristics, when choosing a suitable treatment option for their patients.

Total robotic liver transplant: the final frontier of minimally invasive surgery.

The use of robotic surgery in transplantation is increasing; however, robotic liver transplantation (RLT) remains a challenging undertaking. To our knowledge, this is a report of the first RLT in North America and the first RLT using a whole graft from a deceased donor in the world. This paper describes the preparation leading to the RLT and the surgical technique of the operation. The operation was performed in a 62-year-old man with hepatitis C cirrhosis and hepatocellular carcinoma with a native Model for End-Stage Liver Disease score of 10. The total console time for the operation was 8 hours 30 minutes, and the transplant hepatectomy took 3 hours 30 minutes. Warm ischemia time was 77 minutes. Biliary reconstruction was performed in a primary end-to-end fashion and took 19 minutes to complete. The patient had an uneventful recovery without early allograft dysfunction or surgical complications and continues to do well after 6-months follow-up. This paper demonstrates the feasibility of this operation in highly selected patients with chronic liver disease. Additional experience is required to fully understand the role of RLT in the future of transplant surgery. Narrated video is available at https://youtu.be/TkjDwLryd3I.

Minimally invasive surgeries for spontaneous hypertensive intracerebral hemorrhage (MISICH): a multicenter randomized controlled trial.

BACKGROUND: Intracerebral hemorrhage (ICH) is a common stroke type with high morbidity and mortality. There are mainly three surgical methods for treating ICH. Unfortunately, thus far, no specific surgical method has been proven to be the most effective. We carried out this study to investigate whether minimally invasive surgeries with endoscopic surgery or stereotactic aspiration (frameless navigated aspiration) will improve functional outcomes in patients with supratentorial ICH compared with small-bone flap craniotomy. METHODS: In this parallel-group multicenter randomized controlled trial conducted at 16 centers, patients with supratentorial hypertensive ICH were randomized to receive endoscopic surgery, stereotactic aspiration, or craniotomy at a 1:1:1 ratio from July 2016 to June 2022. The follow-up duration was 6 months. Patients were randomized to receive endoscopic evacuation, stereotactic aspiration, or small-bone flap craniotomy. The primary outcome was favorable functional outcome, defined as the proportion of patients who achieved a modified Rankin scale (mRS) score of 0-2 at the 6-month follow-up. RESULTS: A total of 733 patients were randomly allocated to three groups: 243 to the endoscopy group, 247 to the aspiration group, and 243 to the craniotomy group. Finally, 721 patients (239 in the endoscopy group, 246 in the aspiration group, and 236 in the craniotomy group) received treatment and were included in the intention-to-treat analysis. Primary efficacy analysis revealed that 73 of 219 (33.3%) in the endoscopy group, 72 of 220 (32.7%) in the aspiration group, and 47 of 212 (22.2%) in the craniotomy group achieved favorable functional outcome at the 6-month follow-up (P = .017). We got similar results in subgroup analysis of deep hemorrhages, while in lobar hemorrhages the prognostic outcome was similar among three groups. Old age, deep hematoma location, large hematoma volume, low preoperative GCS score, craniotomy, and intracranial infection were associated with greater odds of unfavorable outcomes. The mean hospitalization expenses were ¥92,420 in the endoscopy group, ¥77,351 in the aspiration group, and ¥100,947 in the craniotomy group (P = .000). CONCLUSIONS: Compared with small bone flap craniotomy, endoscopic surgery and stereotactic aspiration improved the long-term outcome of hypertensive ICH, especially deep hemorrhages. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02811614.

Natural Underwater Bioadhesive Offering Cohesion Modulation via Hydrogen Bond Disruptor: A Highly Injectable and in Vivo Stable Remedy for Gastric Ulcer Resolution.

Injectable bioadhesives are attractive for managing gastric ulcers through minimally invasive procedures. However, the formidable challenge is to develop bioadhesives that exhibit high injectability, rapidly adhere to lesion tissues with fast gelation, provide reliable protection in the harsh gastric environment, and simultaneously ensure stringent standards of biocompatibility. Here, a natural bioadhesive with tunable cohesion is developed based on the facile and controllable gelation between silk fibroin and tannic acid. By incorporating a hydrogen bond disruptor (urea or guanidine hydrochloride), the inherent network within the bioadhesive is disturbed, inducing a transition to a fluidic state for smooth injection (injection force <5 N). Upon injection, the fluidic bioadhesive thoroughly wets tissues, while the rapid diffusion of the disruptor triggers instantaneous in situ gelation. This orchestrated process fosters the formed bioadhesive with durable wet tissue affinity and mechanical properties that harmonize with gastric tissues, thereby bestowing long-lasting protection for ulcer healing, as evidenced through in vitro and in vivo verification. Moreover, it can be conveniently stored (≥3 m) postdehydration. This work presents a promising strategy for designing highly injectable bioadhesives utilizing natural feedstocks, avoiding any safety risks associated with synthetic materials or nonphysiological gelation conditions, and offering the potential for minimally invasive application.

Integrated Sensors for Soft Medical Robotics.

Minimally invasive procedures assisted by soft robots for surgery, diagnostics, and drug delivery have unprecedented benefits over traditional solutions from both patient and surgeon perspectives. However, the translation of such technology into commercialization remains challenging. The lack of perception abilities is one of the obstructive factors paramount for a safe, accurate and efficient robot-assisted intervention. Integrating different types of miniature sensors onto robotic end-effectors is a promising trend to compensate for the perceptual deficiencies in soft robots. For example, haptic feedback with force sensors helps surgeons to control the interaction force at the tool-tissue interface, impedance sensing of tissue electrical properties can be used for tumor detection. The last decade has witnessed significant progress in the development of multimodal sensors built on the advancement in engineering, material science and scalable micromachining technologies. This review article provides a snapshot on common types of integrated sensors for soft medical robots. It covers various sensing mechanisms, examples for practical and clinical applications, standard manufacturing processes, as well as insights on emerging engineering routes for the fabrication of novel and high-performing sensing devices.

Minimally Invasive Left Hepatectomy: Choosing the Suitable Surgical Strategy.

BACKGROUND: Numerous surgical techniques are currently available for minimally invasive left hepatic resection, each offering its own advantages and disadvantages. PATIENTS AND METHODS: This multimedia manuscript delves into the primary approaches for minimally invasive left hepatectomy, with a focus on particular topics such as left hepatic vein approach, transection and middle hepatic vein exposure, and Glissonean approach. We examine key factors that surgeons should consider when choosing among these methods and provide practical recommendations. RESULTS: To enhance understanding, our article includes video footage from multiple centres, showcasing expertly executed surgeries for each approach along with their main considerations. CONCLUSIONS: This multimedia resource will serve as a valuable guide for surgeons, aiding in the selection of the most suitable strategy for minimally invasive left hepatectomies, tailored to the specific needs of the patient and the characteristics of the lesion.

Temporal Trends in Survival Outcomes for Patients with Esophageal Cancer Following Neoadjuvant Chemoradiotherapy: A 14-Year Analysis.

BACKGROUND: The prognosis for patients with esophageal cancer who received neoadjuvant chemoradiotherapy (nCRT) followed by surgery has shown improvement in recent years. We sought to identify the critical factors contributing to enhanced survival outcomes. PATIENTS AND METHODS: We retrospectively examined 427 patients with esophageal cancer treated with nCRT and esophagectomy across two periods: P1 (from 1 January 2004 to 31 December 2011) and P2 (from 1 January 2012 to 31 December 2017). The introduction of the CROSS regimen and total meso-esophagectomy in P2 prompted an evaluation of their effects on perioperative outcomes and overall survival (OS). RESULTS: During P2, the occurrence of recurrent laryngeal nerve palsy increased significantly from 3.9 to 16.8% (p < 0.001), while pneumonia and in-hospital mortality rates remained unchanged. The median OS improved from 19.2 to 29.2 months (p < 0.001) between P1 and P2. Multivariable analysis identified higher nodal yields and the achievement of major response as favorable prognostic factors. Conversely, an involved circumferential resection margin (CRM), an advanced ypN stage, and pneumonia were independently associated with poor outcomes. Patients treated during P2 had a lower prevalence of involved CRM (10% vs. 25.1%, p < 0.001), a higher rate of major response (52.7% vs. 34.8%, p < 0.01), and a greater nodal yield (27.8 vs. 10.9, p < 0.001). CONCLUSIONS: The clinical outcomes following nCRT and surgery have improved significantly over time. This progress can be attributed to multiple factors, with the primary drivers being the refinement of nCRT protocols and the application of radical surgery.

Impact of Liver Cirrhosis, Severity of Cirrhosis, and Portal Hypertension on the Difficulty and Outcomes of Laparoscopic and Robotic Major Liver Resections for Primary Liver Malignancies.

BACKGROUND: Minimally invasive liver resections (MILR) offer potential benefits such as reduced blood loss and morbidity compared with open liver resections. Several studies have suggested that the impact of cirrhosis differs according to the extent and complexity of resection. Our aim was to investigate the impact of cirrhosis on the difficulty and outcomes of MILR, focusing on major hepatectomies. METHODS: A total of 2534 patients undergoing minimally invasive major hepatectomies (MIMH) for primary malignancies across 58 centers worldwide were retrospectively reviewed. Propensity score (PSM) and coarsened exact matching (CEM) were used to compare patients with and without cirrhosis. RESULTS: A total of 1353 patients (53%) had no cirrhosis, 1065 (42%) had Child-Pugh A and 116 (4%) had Child-Pugh B cirrhosis. Matched comparison between non-cirrhotics vs Child-Pugh A cirrhosis demonstrated comparable blood loss. However, after PSM, postoperative morbidity and length of hospitalization was significantly greater in Child-Pugh A cirrhosis, but these were not statistically significant with CEM. Comparison between Child-Pugh A and Child-Pugh B cirrhosis demonstrated the latter had significantly higher transfusion rates and longer hospitalization after PSM, but not after CEM. Comparison of patients with cirrhosis of all grades with and without portal hypertension demonstrated no significant difference in all major perioperative outcomes after PSM and CEM. CONCLUSIONS: The presence and severity of cirrhosis affected the difficulty and impacted the outcomes of MIMH, resulting in higher blood transfusion rates, increased postoperative morbidity, and longer hospitalization in patients with more advanced cirrhosis. As such, future difficulty scoring systems for MIMH should incorporate liver cirrhosis and its severity as variables.

Open versus Minimally Invasive Nephroureterectomy: Contemporary Analysis from a Wide National Population-Based Database.

BACKGROUND: It is generally perceived that minimally invasive nephroureterectomy (MINU), especially in the form of robotic-assisted laparoscopy, is gaining an increasing role in many institutions. OBJECTIVE: The aim of our study was to investigate contemporary trends in the adoption of MINU in the United States compared with open nephroureterectomy (ONU). METHODS: Patients who underwent ONU or MINU between 2011 and 2021 were retrospectively analyzed using PearlDiver Mariner, an all-payer insurance claims database. International Classification of Diseases diagnosis and procedure codes were used to identify the type of surgical procedure, patients' characteristics, social determinants of health (SDOH), and perioperative complications. The primary objective assessed different trends and costs in NU adoption, while secondary objectives analyzed factors influencing the postoperative complications, including SDOH. Outcomes were compared using multivariable regression models. RESULTS: Overall, 15,240 patients underwent ONU (n = 7675) and MINU (n = 7565). Utilization of ONU declined over the study period, whereas that of MINU increased from 29 to 72% (p = 0.01). The 60-day postoperative complication rate was 23% for ONU and 19% for MINU (p < 0.001). At multivariable analysis, ONU showed a significantly higher risk of postoperative complications (odds ratio 1.33, 95% CI 1.20-1.48). Approximately 5% and 9% of patients reported at least one SDOH at baseline for both ONU and MINU (p < 0.001). CONCLUSIONS: Contemporary trend analysis of a large national dataset confirms that there has been a significant shift towards MINU, which is gradually replacing ONU. A minimally invasive approach is associated with lower risk of complications. SDOH are non-clinical factors that currently do not have an impact on the outcomes of nephroureterectomy.

A Practical Guide to Inflow Control, Retraction, and Exposure for Robotic Hepatectomy.

Establishment of inflow control and gentle effective retraction of the liver for optimal exposure are critical to safe hepatectomy. Multiple methods have been previously reported for inflow control in minimally invasive (MIS) hepatectomy including Huang's Loop.1-3 We describe here the assembly and use of our modified version of Huang's loop that permits adjustable, atraumatic, and totally intracorporeal inflow control. We use a soft 16-French urinary catheter with a single premade opening near the blunt tip, across which a small slit is created. A beveled cut is made to the catheter 12-15 cm from the blunt tip and a suture sewn there that can be grasped to pull this beveled tail through the slit and window around the porta hepatis; this loop can be tightened or loosened with ease. For liver retraction, current techniques can be traumatic, especially when instruments apply traction directly onto the liver.4 Our preferred approach utilizes a liver sling made from a soft, rolled surgical sponge with 15-cm silk ties secured at each end; the length of the sling can be adjusted on the basis of thickness of the liver. The sling applies gentle, atraumatic "pulling" traction and is especially useful for exposure of the right posterior sector. We also use external band retraction to align the transection plane with the camera.5 Both also provide countertraction when advancing instruments into a firm or fibrotic liver. These techniques are commonly used in our MIS practice, and we have found them to be cost-efficient, easily reproducible, and effective.

The Impact of D2 Versus D1 Lymphadenectomy in Siewert II Gastroesophageal Junction (GEJ) Cancer.

BACKGROUND: Although multiple treatment options exist for gastroesophageal junction (GEJ) cancer, surgery remains the mainstay for potential cure. Extended nodal dissection with a D2 lymphadenectomy (LAD) remains controversial for Siewert II GEJ cancer. Although D2 LAD may lead to a greater lymph node harvest, its effect on survival remains elusive. The authors hypothesized that additional D2 dissection in Siewert II GEJ cancer does not lead to increased survival. METHODS: This study reviewed Siewert II patients who received a D1 or D2 LAD in addition to minimally invasive esophagectomy (MIE) after receiving neoadjuvant chemoradiation or perioperative chemotherapy (2012-2022). The patients were followed for up to 5 years. The outcomes measured were survival, number of nodes sampled, and operative time. The association between D1 or D2 LAD and overall survival was analyzed with Kaplan-Meier methods and a multivariable Cox regression model. RESULTS: Among 155 patients, 74 % underwent D1 and 26 % underwent D2 LAD. The patients with D2 had more than 15 lymph nodes harvested more frequently than those who had D1 (83 % vs 48 %; p < 0.001), with no difference in positive nodes (2.8 ± 5.2 vs 2.1 ± 4.2; p = 0.4). The patients with D2 LAD had a longer median operative time than those who with D1 LAD (362 vs 244 min; p < 0.001). In Kaplan-Meier and multivariable Cox regression models, overall survival differed significantly between the patients undergoing D2 and those who had D1 (adjusted hazard ratio [aHR], 0.52; 95 % confidence interval [CI], 0.25-1.00; p = 0.067). CONCLUSIONS: Little consensus exists regarding the optimal lymph node harvest for GEJ cancers. In Siewert II cancer, D2 LAD may not be mandatory and may lead to increased operative morbidity with no significant difference in survival.

Prevalence of and Factors Associated with Financial Toxicity After Pancreatectomy and Gastrectomy.

BACKGROUND: Financial toxicity (FT) refers to the adverse impact of cancer treatment costs on patients' experiences, potentially leading to poor adherence to treatment and outcomes. However, the prevalence of FT among patients undergoing major upper gastrointestinal cancer operations, as well as factors associated with FT, remain unclear. METHODS: We conducted a cross-sectional study by sending the Comprehensive Score for financial Toxicity (COST) survey and Surgery-Q (a survey specifically developed for this study) to patients who underwent gastrectomy or pancreatectomy for malignant disease at our institution in 2019-2021. RESULTS: We sent the surveys to 627 patients and received responses from 101 (16%) patients. The FT prevalence (COST score <26) was 48 (48%). Patients likely to experience FT were younger than 50 years of age, of non-White race, earned an annual income <$75,000, and had credit scores <740 (all p < 0.05). Additionally, longer hospital stay (p = 0.041), extended time off work for surgery (p = 0.011), and extended time off work for caregivers (p = 0.005) were associated with FT. Procedure type was not associated with FT; however, patients who underwent minimally invasive surgery (MIS) had a lower FT probability (p = 0.042). In a multivariable analysis, age <50 years (p = 0.031) and credit score <740 (p < 0.001) were associated with high FT risk, while MIS was associated with low FT risk (p = 0.024). CONCLUSIONS: Patients with upper gastrointestinal cancer have a major risk of FT. In addition to predicting the FT risk before surgery, facilitating quicker functional recovery with the appropriate use of MIS is considered important to reducing the FT risk.

Minimally Invasive Esophagectomy Provides Better Short- and Long-Term Outcomes Than Open Esophagectomy in Locally Advanced Esophageal Cancer.

BACKGROUND: Minimally invasive esophagectomy (MIE) has been increasingly performed for locally advanced esophageal cancer in place of open transthoracic esophagectomy (OE). This study explored the significance of MIE for esophageal squamous cell carcinoma (ESCC), focusing mainly on the depth of primary esophageal tumors. METHODS: This study retrospectively assessed short- and long-term outcomes of patients who underwent esophagectomy for ESCC from 2005 through 2021. The inverse probability of the treatment-weighting (IPTW) method was used to compare the outcomes between OE and MIE. The outcomes also were evaluated in the subgroups stratified by cT category. RESULTS: Among 1117 patients, 447 (40%) underwent OE and 670 (60%) underwent MIE. After IPTW adjustment, the incidence of any postoperative complications was significantly higher in the OE group than in the MIE group (60.8% vs 53.7%; p = 0.032), whereas the R0 resection rate was significantly higher in the MIE group (98.6% vs 92.7%; p < 0.001). The MIE group showed better 3 year overall and cancer-specific survival than the OE group (p < 0.001). The incidence of locoregional recurrence within the surgical field was significantly more frequent in the OE group (p < 0.001). In the subgroup analysis stratified by cT category, the R0 resection rate was significantly higher and the incidence of locoregional recurrence was lower in the MIE group among the patients with cT3-4 tumors. In the patients with cT1-2 tumors, MIE showed no significant benefit over OE. CONCLUSIONS: For the patients with cT3-4 tumors, MIE showed fewer postoperative complications, better locoregional control, and better prognosis than OE. Compared with OE, MIE is beneficial, especially for locally advanced ESCC.

Uterine Anastomosis with Low Anterior Resection.

In this surgical teaching video, we demonstrate the technique of robot-assisted uterine anastomosis combined with low anterior resection in a 27-year-old patient with T2 node-positive rectal cancer. The patient had undergone uterine transposition for fertility preservation prior to upfront chemotherapy and radiation therapy for rectal cancer. In this video, we review the key steps of both surgical procedures. We emphasize robot trocar placement and docking, demonstrate optimal organ manipulation and tissue handling, and include key operative modifications and pearls for successful perioperative management.

Long-Term Survival Outcomes After Minimally Invasive Surgery for Ileal Neuroendocrine Tumors.

BACKGROUND: Ileal neuroendocrine tumors (i-NETs) are characterized by their multifocality and bulky mesenteric mass. Having shown that minimally invasive surgery (MIS) utilizing a hand-access port device has favorable short-term outcomes and achieves the goals of surgery for i-NETs, we sought to analyze long-term survival outcomes of MIS. METHODS: One hundred and sixty-eight patients who underwent resection of primary i-NETs at a single institution between January 2007 and February 2023 were retrospectively studied. Patients were categorized into the MIS or open surgery cohorts on an intention-to-treat basis. Open surgery was selected mainly based on the need for hepatectomy or bulky mesenteric mass resection. Overall survival was analyzed using log-rank tests with propensity score matching (PSM) and Cox proportional hazards regression. PSM was performed to reduce standardized mean differences of the variables to <0.2. RESULTS: Overall, 129 (77%) patients underwent MIS and 39 (23%) underwent open surgery. Twenty-seven MIS patients were converted to an open procedure. The median follow-up time was 49 months (interquartile range 23-87 months). In the PSM cohorts, overall survival did not differ significantly between the MIS and open surgery cohorts {median 99 months (95% confidence interval [CI] 91-not applicable [NA]) vs. 103 months (95% CI 86-NA), p = 0.77; hazard ratio 0.87 (95% CI 0.33-2.2), p = 0.77}. CONCLUSIONS: MIS is an alternative to open surgery for i-NETs, achieving similar short- and long-term oncological outcomes. Bulky mesenteric mass and a plan for concurrent liver resection are potential criteria for open surgery.

Effect of Resected Lung Volume on Pulmonary Function and Residual Lung Volume in Patients Undergoing Segmentectomy: A Retrospective Study.

PURPOSE: We elucidated the effects of planned resection volume on postoperative pulmonary function and changes in residual lung volume during segmentectomy. METHODS: This study included patients who underwent thoracoscopic segmentectomy between January 2017 and December 2022 and met eligibility criteria. Pre- and post-resection spirometry and computed tomography were performed. Three-dimensional reconstructions were performed by using computed tomography images to calculate the volumes of the resected, remaining, and nonoperative side regions. Based on the resected region volume, patients were divided into the higher and lower volume segmentectomy groups. Changes in lung volume and pulmonary function before and after the surgery were comparatively analyzed. RESULTS: The median percentage of resected lung volume was 10.9%, forming the basis for categorizing patients into the two groups. Postoperative forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) ratios to preoperative measurements in both groups did not differ significantly (FEV1, p = 0.254; FVC, p = 0.777). Postoperative FEV1 and FVC ratios to their predicted postoperative values were significantly higher in the higher volume segmentectomy group than in the lower volume segmentectomy group (FEV1, p = 0003; FVC, p < 0.001). The higher volume segmentectomy group showed significantly greater post-to-preoperative lung volume ratio in overall, contralateral, ipsilateral, residual lobe and residual segment than the lower volume segmentectomy group. CONCLUSIONS: Postoperative respiratory function did not differ significantly between the higher- and lower-volume segmentectomy groups, indicating improved respiratory function because of substantial postoperative residual lung expansion. Our findings would aid in determining the extent of resection during segmentectomy.

The Effect of Neoadjuvant Therapy on Esophagectomy for cT2N0M0 Esophageal Adenocarcinoma.

BACKGROUND: For cT2N0M0 esophageal adenocarcinomas, the effects of neoadjuvant chemoradiotherapy (NT) on surgical outcomes and the oncological benefits to the patients are debatable. In this study, we investigated the optimal management for cT2N0M0 adenocarcinoma (1) assessing the perioperative impact of NT on esophagectomy and (2) evaluating the oncologic effect of NT in a homogeneous group of patients with clinical stage IIA. We hypothesized that NT does not negatively affect perioperative outcomes and provides an oncologic benefit to selected patients with cT2N0M0 disease. METHODS: The National Cancer Database was queried (2010-2019) for patients with cT2N0M0 esophageal adenocarcinoma undergoing esophagectomy. After propensity-matching to adjust for differences in patient and tumor characteristics, we compared postoperative outcomes (logistic regression) and survival (Kaplan-Meier and Cox regression) among those who underwent NT vs upfront surgery (S). RESULTS: This study included 3413 patients, of whom 2359 (69%) received NT, and 1054 (31%) S. In contrast to those who underwent S, in the matched cohort, patients treated with NT had comparable conversion rates (8% vs11.1%, p = 0.06), length of stay (9 vs 10 days, p = 0.078), unplanned readmission (5.4% vs 8.8%, p = 0.109), and 30- (3.9% vs 3.7%, p = 0.90) and 90-day mortality (5.7% vs 4.7%, p = 0.599). In addition, NT associated with improved survival in patients with cT2N0M0 tumors > 5 cm (HR 0.30, 95% CI 0.17-0.36). CONCLUSIONS: NT does not appear to increase technical complexity or to adversely affect postoperative outcomes after esophagectomy. Furthermore, minimally invasive esophagectomy is feasible following NT, with comparable conversion rates to those who had upfront surgery. Lastly, NT was selectively associated with improved survival in patients with cT2N0M0 esophageal cancer.