Development and validation of a preoperative "difficulty score" for laparoscopic transabdominal adrenalectomy: a multicenter retrospective study

Current state-of-the-art of adrenal surgery in Italy: the cancer risk in surgical adrenal lesions (CRISAL) survey

Adrenalectomies are growing worldwide because of the frequent diagnosis of incidentaloma and the use of minimally invasive surgery (MIS). The factors used to identify a malignant lesion and the best surgical technique are uncertain. In this context, the definition of high-volume center and expert surgeon is under debate. The Italian Society of Endoscopic Surgery and New Technologies (SICE) developed a nationwide survey to investigate the state-of-the-art of adrenal surgery in Italy. A web-based survey comprising 37 questions was developed and distributed to Italian surgeons involved in adrenal surgery. Two hundred forty-eight answers were analyzed. Consensus was reached among the survey participants regarding local infiltration (83%) and rapid growth of the lesion (81%) as markers of malignancy. Nearly 30% of the participants used MIS in case of malignant adrenal lesions. The lateral (50%) and anterior transperitoneal (44%) approaches were the most common among Italian surgeons. Approximately 40% of participants believe that 20-40 adrenalectomies/year are needed to define an expert surgeon and at least 20 procedures/year to define a high-volume center. Approximately half of participants performed < 10 adrenalectomies/year in centers with a median volume < 10 procedures/year. Based on participant feedback, this survey highlights local infiltration and rapid growth as the most significant markers of malignant adrenal lesions. While open adrenalectomy remains the gold standard for suspected malignant lesions, nearly 30% of the participants practice MIS even in these cases. The lateral and anterior transperitoneal approaches emerge as the most familiar for Italian surgeons. A substantial proportion of Italian patients with adrenal lesions undergo surgery performed by surgeons with an annual case volume < 10 procedures, at centers with a low annual volume of adrenalectomies. Moreover, there is a lack of standardized definitions for 'expert surgeon' and 'high-volume center' in this context.

Evaluation of predictive factors for i-CLARAS (intraoperative complications in laparoscopic renal and adrenal surgery): a multicentre international retrospective cohort study

The laparoscopic approach represents the standard of treatment for renal and adrenal diseases, and its use is increasing even outside referral centres. Although most procedures are routinely performed, intraoperative complications do not occur, and the rate and predictive factors of these complications have not been established. The aim of this study was to evaluate the incidence and type of intraoperative complications and to identify predictive factors in patients undergoing laparoscopic renal and adrenal surgery. This was a cohort, multicentre, international retrospective study. Patients who underwent laparoscopic renal and adrenal surgeries between April 2017 and March 2022 were included in the study. Bivariate analysis was performed using contingency tables and the χ2 test for independent samples to compare qualitative variables and the T test and Mood test for continuous variables. Multivariate analysis was performed using a logistic regression model to obtain adjusted odds ratios. A total of 2374 patients were included in the study. Intraoperative complications were reported for 8.09% of patients who underwent renal surgery, with the most common complications reported being hollow viscus and vascular complications, and for 6.75% of patients who underwent adrenal surgery, with the most common complication reported being parenchymatous viscous complications. Multivariate analysis revealed that both adrenal and renal surgery radiological preoperative factors, such as invasive features during adrenalectomy and the RENAL score during nephrectomy, are predictive factors of intraoperative complications. In contrast to existing data, surgeon experience was not associated with a reduction in the incidence of perioperative complications.

Development and validation of machine-learning models for the difficulty of retroperitoneal laparoscopic adrenalectomy based on radiomics

Objective

The aim is to construct machine learning (ML) prediction models for the difficulty of retroperitoneal laparoscopic adrenalectomy (RPLA) based on clinical and radiomic characteristics and to validate the models.

Methods

Patients who had undergone RPLA at Shanxi Bethune Hospital between August 2014 and December 2020 were retrospectively gathered. They were then randomly split into a training set and a validation set, maintaining a ratio of 7:3. The model was constructed using the training set and validated using the validation set. Furthermore, a total of 117 patients were gathered between January and December 2021 to form a prospective set for validation. Radiomic features were extracted by drawing the region of interest using the 3D slicer image computing platform and Python. Key features were selected through LASSO, and the radiomics score (Rad-score) was calculated. Various ML models were constructed by combining Rad-score with clinical characteristics. The optimal models were selected based on precision, recall, the area under the curve, F1 score, calibration curve, receiver operating characteristic curve, and decision curve analysis in the training, validation, and prospective sets. Shapley Additive exPlanations (SHAP) was used to demonstrate the impact of each variable in the respective models.

Results

After comparing the performance of 7 ML models in the training, validation, and prospective sets, it was found that the RF model had a more stable predictive performance, while xGBoost can significantly benefit patients. According to SHAP, the variable importance of the two models is similar, and both can reflect that the Rad-score has the most significant impact. At the same time, clinical characteristics such as hemoglobin, age, body mass index, gender, and diabetes mellitus also influenced the difficulty.

Conclusion

This study constructed ML models for predicting the difficulty of RPLA by combining clinical and radiomic characteristics. The models can help surgeons evaluate surgical difficulty, reduce risks, and improve patient benefits.

Impact of Current Technology in Laparoscopic Adrenalectomy: 20 Years of Experience in the Treatment of 254 Consecutive Clinical Cases

BACKGROUND

Laparoscopic adrenalectomy (LA), which avoids large abdomen incisions, is considered the gold standard technique for the treatment of benign small- and medium-size adrenal masses (<6 cm) and weighing < 100 g. A trascurable mortality and morbidity rate, short hospitalization and patient rapid recovery are the main advantages compared to traditional surgery. During the past decade, a new surgical technology has been developed that expedites a "clipless" adrenalectomy. Here, the authors analyze a clinical series of 254 consecutive patients who were affected by adrenal gland neoplasms and underwent LA by the transabdominal lateral approach over the two last decades. A literature review is also presented.

METHODS

Preoperative, intraoperative and postoperative data from 254 patients who underwent LA between January 2003 and December 2022 were retrospectively collected and reviewed. Diagnosis was obtained on the basis of clinical examination, laboratory values and imaging techniques. Doxazosin was preoperatively administered in the case of pheochromocytoma (PCC) while spironolactone and potassium were employed to treat Conn's disease. The same surgeon (CG) performed all the LA and utilized the same laparoscopic transabdominal lateral approach. Different dissection tools-ultrasonic, bipolar or mixed scissors-and hemostatic agents were used during this period. The following results were obtained: 254 patients were included in the study; functioning tumors were diagnosed in 155 patients, 52 patients were affected by PCCs, 55 by Conn's disease, 48 by Cushing's disease. Surgery mean operative time was 137.33 min (range 100-180 min) during the learning curve adrenalectomies and 98.5 min (range 70-180) in subsequent procedures. Mean blood loss was respectively 160.2 mL (range 60-280) and 96.98 mL (range 50-280) in the first 30 procedures and the subsequent ones. Only three conversions (1.18%) to open surgery occurred. No mortality or postoperative major complications were observed, while minor complications occurred in 19 patients (3.54%). In 153 out of 155 functioning neoplasms, LA was effective in the normalization of the endocrine profile. According to our experience, a learning curve consisting of 30 cases was identified. In fact, a lower operative time and a lower complication rate was reported following 30 LA.

CONCLUSIONS

LA is a safe procedure, even for masses larger than 6 cm and PCCs. Undoubtedly, the development of surgical technology has made it possible reducing operative times, performing a "clipless" adrenalectomy and extending the indications in the treatment of more complex patients. A multidisciplinary team, in referral high-volume centers, is recommended in the management of adrenal pathology. A 30-procedure learning curve is necessary to improve surgical outcomes.

Development and validation of a preoperative difficulty scoring system for endoscopic resection of gastric gastrointestinal stromal tumor: a multi-center study

BACKGROUND

Endoscopic resection (ER) is a promising technique for resecting gastric gastrointestinal stromal tumors (gGISTs); however, ER is technically challenging. This study aimed to develop and validate a difficulty scoring system (DSS) to determine the difficulty for ER of a gGIST.

METHODS

This retrospective study enrolled 555 patients with gGISTs in multi-centers from December 2010 to December 2022. Data on patients, lesions, and outcomes of ER were collected and analyzed. A difficult case was defined as an operative time ≥ 90 min, or the occurrence of severe intraoperative bleeding, or conversion to laparoscopic resection. The DSS was developed in the training cohort (TC) and validated in the internal validation cohort (IVC) and external validation cohort (EVC).

RESULTS

The difficulty occurred in 97 cases (17.5%). The DSS comprised the following: tumor size ≥ 3.0 cm (3 points) or 2.0-3.0 cm (1 point); location in the upper third of the stomach (2 points); invasion depth beyond the muscularis propria (2 points); lack of experience (1 point). The area under the curve (AUC) of DSS in IVC and EVC was 0.838 and 0.864, respectively, and the negative predictive value (NPV) was 0.923 and 0.972, respectively. The proportions of difficult operation in easy (score 0-3), intermediate (score 4-5), and difficult (score 6-8) categories were 6.5%, 29.4%, and 88.2% in the TC, 7.7%, 45.8%, and 85.7% in the IVC, and 7.0%, 29.4%, and 85.7% in the EVC, respectively.

CONCLUSIONS

We developed and validated a preoperative DSS for ER of gGISTs based on tumor size, location, invasion depth, and endoscopists' experience. This DSS can be used to grade the technical difficulty before surgery.

Automated machine learning to predict the difficulty for endoscopic resection of gastric gastrointestinal stromal tumor

Background

Accurate preoperative assessment of surgical difficulty is crucial to the success of the surgery and patient safety. This study aimed to evaluate the difficulty for endoscopic resection (ER) of gastric gastrointestinal stromal tumors (gGISTs) using multiple machine learning (ML) algorithms.

Methods

From December 2010 to December 2022, 555 patients with gGISTs in multi-centers were retrospectively studied and assigned to a training, validation, and test cohort. A difficult case was defined as meeting one of the following criteria: an operative time ≥ 90 min, severe intraoperative bleeding, or conversion to laparoscopic resection. Five types of algorithms were employed in building models, including traditional logistic regression (LR) and automated machine learning (AutoML) analysis (gradient boost machine (GBM), deep neural net (DL), generalized linear model (GLM), and default random forest (DRF)). We assessed the performance of the models using the areas under the receiver operating characteristic curves (AUC), the calibration curve, and the decision curve analysis (DCA) based on LR, as well as feature importance, SHapley Additive exPlanation (SHAP) Plots and Local Interpretable Model Agnostic Explanation (LIME) based on AutoML.

Results

The GBM model outperformed other models with an AUC of 0.894 in the validation and 0.791 in the test cohorts. Furthermore, the GBM model achieved the highest accuracy among these AutoML models, with 0.935 and 0.911 in the validation and test cohorts, respectively. In addition, it was found that tumor size and endoscopists' experience were the most prominent features that significantly impacted the AutoML model's performance in predicting the difficulty for ER of gGISTs.

Conclusion

The AutoML model based on the GBM algorithm can accurately predict the difficulty for ER of gGISTs before surgery.

Factors affecting the quality of laparoscopic D2 lymph node dissection for gastric cancer: a cohort study from two randomized controlled trials

BACKGROUND

Laparoscopic D2 lymph node dissection (LND) for gastric cancer has a wide range and high difficulty. In the past, the quality of surgery was often judged by the time of the operation or the amount of blood loss, but the analysis based on surgical video was rarely reported. The purpose of this study was to analyze the relationship between the quality of laparoscopic D2 LND for gastric cancer and postoperative complications.

METHODS

The surgical video and clinicopathological data of 610 patients in two randomized controlled trials in our center from 2013 to 2016 were retrospectively analyzed. Klass-02-QC LND scale and general error score tool were used to quantitatively evaluate the intraoperative performance of D2 LND. Logistic regression was used to analyze the influencing factors of postoperative complications.

RESULTS

The overall incidence of complications (CD classification≥2) was 20.6%; the incidence of surgical complications was 6.9%. According to whether the LND score reached 44, patients were divided into a qualified group (73%) and a not-qualified group (27%). Event score (ES) by quartile was divided into grade 1 (21.7%), grade 2 (26%), grade 3 (28%), and grade 4 (24.3%) from low to high. Univariate logistic regression analysis showed that ES greater than or equal to 3, tumor size greater than or equal to 35 mm, and cTNM >II were independent risk factors for not-qualified LND. Male,tumor size greater than or equal to 35 mm and cTNM >II were independent risk factors for grade 4 ES. Not-qualified LND (OR=1.62, 95% CI: 1.16-3.89, P =0.021), grade 4 ES (OR=3.21, 95% CI: 1.52-3.90, P =0.035), and cTNM >II (OR=1.74, 95% CI: 1.39-7.33, P =0.041) were independent risk factors for postoperative surgical complications.

CONCLUSIONS

The qualification of LND and intraoperative events based on surgical video are the independent influencing factors of postoperative complications of laparoscopic gastric cancer surgery. Specialist training and teaching based on surgical video may help to improve the surgical skills of specialists and improve the postoperative outcome of patients.

Is transperitoneal laparoscopic adrenalectomy for pheochromocytoma really more challenging? A propensity score-matched analysis

PURPOSE

Minimally invasive surgery is the gold standard treatment for adrenal masses, but it may be a challenging procedure in the case of pheochromocytoma (PHEO). The aim of the present study is to report the results of transperitoneal laparoscopic adrenalectomy (TLA) in cases of PHEO in comparison to other types of adrenal lesions.

METHODS

From 1994 to 2021, 629 patients underwent adrenalectomy. Twenty-two and thirty-five patients, respectively, were excluded because they underwent bilateral and open adrenalectomy, leaving 572 patients for inclusion. Of these, 114 patients had PHEO (Group A), and 458 had other types of lesions (Group B). To adjust for potential baseline confounders, a propensity score matching (PSM) analysis was conducted.

RESULTS

After PSM, 114 matched pairs of patients were identified from each group. Statistically significant differences were not observed when comparing the median operative time (85 and 90 min in Groups A and B, respectively, p = 0.627), conversion rate [6 (5.3%) in each group, p = 1.000], transfusion rate [4 (3.5%) and 3 (2.6%) in Groups A and B, respectively, p = 1.000], complication rate [7 (6.1%) and 9 (7.9%) in Groups A and B, respectively, p = 0.796), median postoperative hospital stay (3.9 and 3.6 days in Groups A and B, respectively, p = 0.110), and mortality rate [1 (0.9%) in each group, p = 1.000].

CONCLUSIONS

Based on this analysis, the results of TLA for PHEO are equivalent to those of TLA for other types of adrenal lesions, but the fundamental requirements are multidisciplinary patient management and adequate surgeon experience. Further prospective studies are required to draw definitive conclusions.

Minimally invasive techniques in benign and malignant adrenal tumors

Minimally invasive adrenalectomy has become the main treatment modality for most adrenal lesions. Both laparoscopic transabdominal and retroperitoneoscopic approaches are safe and feasible options, each with respective advantages, including better surgical outcomes, fewer complications, and faster recovery over open adrenalectomy. While open surgery remains a valid modality in treatment of adrenocortical cancer in the presence of some findings such as invasion, robotic platforms, and minimally invasive surgery have gained popularity as technology continues to evolve. Organ preservation during adrenalectomy is feasible in some conditions to prevent adrenal insufficiency. Ablative technologies are increasingly utilized in benign and malignant tumors, including the adrenal gland, with various outcomes. A multidisciplinary team, an experienced surgeon, and a high-volume center are recommended for any surgical approaches and management of adrenal lesions. This review article evaluated recent findings and current evidence on minimally invasive adrenalectomy.

Two Decades' Outcomes and Trends of Adrenalectomy for Benign Pathologies in Veterans

BACKGROUND

Since the introduction of laparoscopic adrenalectomy (LA) in 1992, it has become the standard of care for most adrenal benign pathologies. This study compares the outcomes and trends of open (OA) versus LA in veterans for benign pathologies.

METHODS

Veterans Affairs Surgical Quality Improvement Program was queried for adrenalectomies performed for benign pathologies during the period 2000-2019. Data collection included demographics, comorbidities, operative details, and postoperative outcomes.

RESULTS

A total of 1683 patients were included (91.4% males, mean age 59.6, mean body mass index 31.2, and 87.2% with American Society of Anesthesiologists class≥III). Overall, the mean operative time (OT) was 3.2 hours, the majority performed by general surgeons (71.4%), and the mean length of stay (LOS) was 4.1 days. There were 12 (0.7%) 30-day mortalities, and 162 patients (8.8%) developed ≥1 complication. LA was performed in 70.9% (1306), with the conversion rate of 0.85% (10). When compared with OA, patients with the laparoscopic approach were functionally independent, shorter OT, less intraoperative blood transfusion, shorter LOS, and lower mortality and morbidity. Dependent functional status, congestive heart failure, American Society of Anesthesiologists class ≥III, and smoking were independent predictors of mortality, whereas intraoperative transfusions, chronic obstructive pulmonary disease, and dependent functional status were predictors of morbidity. Trend analysis showed an 8-fold increase in the use of LA. However, trend analysis for morbidity and mortality rates showed no significant change for both approaches.

CONCLUSION

LA is being well adopted in the veterans affairs system with an 8-fold increase over 20 years, with lower morbidity and mortality compared with the open approach for benign adrenal pathologies.

High-Volume Center Experience with Laparoscopic Adrenalectomy over Two Decades

Background: Study aims to demonstrate single-institution two decades experience with lateral transperitoneal laparoscopic adrenalectomies. Methods: Retrospective study involved 991 operations grouped into 4 cohorts. Data was collected on the patients’ age, sex, side and size of the lesion, histopathological type, hormonal activity, conversion to open adrenalectomy, operating time, length of hospital stay, perioperative complications. Results: The operations were right-sided (n = 550), left-sided (n = 422), bilateral (n = 19). Mean tumor size was 41.9 mm. Histopathological examination revealed 442 adenomas, 191 nodular hyperplasias, 218 pheochromocytomas, 33 malignancies and 126 other lesions. 541 patients had hormonally active tumors. Mean operating time for unilateral laparoscopic adrenalectomy was 141 min. Mean length of hospital stay was 5.27 days. Intraoperative complications rate was 2.3%. Conversion rate was 1.5%. 54 of patients had 70 postoperative complications. Reoperation rate was 1%. Mortality rate was 0.1%. Statistically significant differences were found in all factors, apart from age, sex, side and size of the lesion, reoperations rate (p > 0.05). Conversions rate, complications rates, length of hospital stay were highest in the first group (p < 0.05). Operating time shortened in the first decade. Conclusions: Laparoscopic adrenalectomy is a safe procedure with negligible mortality. Conversions rate, perioperative complications rate, and length of hospital stay, significantly decreased over time.

Perioperative factors influencing the difficulty of retroperitoneal laparoscopic adrenalectomy: a single-center retrospective study

Purpose

Identifying patients in whom adrenalectomy may be more difficult can help with surgical decision-making. This study investigated the perioperative factors affecting the difficulty of retroperitoneal laparoscopic adrenalectomy (RLA).

Methods

Sixty-eight patients who underwent RLA at our hospital between December 1, 2020 and May 1, 2021 were included. The difficulty of RLA was assessed by operating time and intraoperative blood loss. We analyzed the relationship between surgical difficulty and patient sex, age, and body mass index, pathological type, tumor side, tumor size, distance from the lower pole of the adrenal tumor to the upper pole of the kidney (DAK), and distance from the lower pole of the adrenal tumor to the renal pedicle (DARP).

Results

Mean operating time was 105.38 ± 33.31 min and mean intraoperative blood loss was 32.28 ± 22.88 ml. Univariate linear regression analysis showed that age (P = 0.047), tumor size (P = 0.002), DAK (P = 0.002), and DARP (P < 0.001) were significantly correlated with a longer operating time. Univariate logistic regression analysis showed that DARP (P = 0.001), DAK (P = 0.001), tumor size (P = 0.002), and age (P = 0.033) were significantly correlated with a longer operating time. Multivariate logistic regression indicated that DARP (OR 5.341; 95% CI 1.704–16.739; P = 0.004), and tumor size (OR 4.433; 95% CI 1.434–13.709; P = 0.010) were independent predictors of operating time.

Conclusion

Age, tumor size, DAK, and DARP were predictors of the difficulty of RLA. Older age, lower DARP and DAK, and a larger tumor size were associated with a longer operating time. DARP and tumor size were independent predictors of surgical difficulty.

A nomogram for evaluation and analysis of difficulty in retroperitoneal laparoscopic adrenalectomy: A single-center study with prospective validation using LASSO-logistic regression

BACKGROUND

While it is known that inaccurate evaluation for retroperitoneal laparoscopic adrenalectomy (RPLA) can affect the surgical results of patients, no stable and effective prediction model for the procedure exists. In this study, we aimed to develop a computed tomography (CT) -based radiological-clinical prediction model for evaluating the surgical difficulty of RPLA.

METHOD

Data from 398 patients with adrenal tumors treated by RPLA in a single center from August 2014 to December 2020 were retrospectively analyzed and divided into sets. The influencing factors were selected by least absolute shrinkage and selection operator regression model (LASSO). Additionally, the nomogram was constructed. A receiver operating characteristic curve was used to analyze the prediction efficiency of the nomogram. The C-index and bootstrap self-sampling methods were used to verify the discrimination and consistency of the nomogram.

RESULT

The following 11 independent influencing factors were selected by LASSO: body mass index, diabetes mellitus, scoliosis, hyperlipidemia, history of operation, tumor diameter, distance from adrenal tumor to upper pole of kidney, retro renal fat area, hyperaldosteronism, pheochromocytoma and paraganglioma, and myelolipoma. The area under the curve (AUC) of the training set was 0.787, and 0.844 in the internal validation set. Decision curve analyses indicated the model to be useful. An additional 117 patients were recruited for prospective validation, and AUC was 0.848.

CONCLUSION

This study developed a radiological-clinical prediction model proposed for predicting the difficulty of RPLA procedures. This model was suitable, accessible, and helpful for individualized surgical preparation and reduced operational risk. Thus, this model could contribute to more patients' benefit in circumventing surgical difficulties because of accurate predictive abilities.