Risk factors for prolonged hospitalization in patients undergoing laparoscopic adrenalectomy

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.

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.

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.

Should surgical drainage after lateral transperitoneal laparoscopic adrenalectomy be routine?-A retrospective comparative study

Background

Whether to use surgical drains after abdominal surgery or not has received much attention since a hundred years ago. Nowadays, lateral transperitoneal laparoscopic adrenalectomy (LTLA) is a widely used technique to treat adrenal tumors worldwide. However, the placement of drains after LTLA remains controversial.

Methods

Data of 150 patients, who underwent LTLA between October 2014 and September 2020 by the same lead surgeon, were collected, including demographic, pathology, preoperative, operative variables and postoperative complications. The patients were divided into two groups, with and without drainage. The postoperative recovery of the two groups was compared.

Results

Among 150 patients (65 men and 85 women, median age 48 years, median BMI 23.53), 89 patients had no drainage and 61 patients had drainage after surgery. Variables of the two groups were analyzed. Placement of drains correlated with long operative time (P<0.01). Patients with drain had longer hospital stays (P<0.001) and a higher incidence of postoperative complications (P=0.022). Other factors, including tumor size (P=0.61), tumor location (P=0.387), ASA score (P=0.687), pathology (P=0.55), VAS pain score (P=0.41), intraoperative blood loss (P=0.11), were not found to be significantly associated with drain placement. There was no conversion to open surgery in both groups. Moreover, no mortality was observed in either group.

Conclusions

This study revealed that it is feasible and safe not to leave a drain in selective and uncomplicated patients and that surgical drainage should not be routine after LTLA.

Factors associated with prolonged hospital stay after laparoscopic adrenalectomy

Laparoscopy is the standard technique for resecting adrenal tumors, but short-term outcomes such as length of stay (LOS) vary widely between centers. We aimed to identify factors associated with LOS after lateral transperitoneal laparoscopic adrenalectomy (LTLA). We analyzed consecutive patients undergoing unilateral LTLA between April 2003 and April 2020. Prolonged LOS was defined as a stay longer than the 75th percentile of the overall cohort. To identify potential factors associated with prolonged LOS, we compared collected data from patients with LOS ≤ 2 days versus LOS > 2 days and elaborated multivariate logistic regression models. We included 150 patients (73 men and 77 women, median age 54 years), with benign (n = 128) and malignant tumors (n = 22). The median LOS after LTLA was 2 days; 64 (42.7%) patients had prolonged hospitalization. Variables significantly associated with prolonged LOS in the univariate analysis included ASA III + IV (p = 0.016), pheochromocytoma (p < 0.001), learning curve (p = 0.032), surgery on Thursday or Friday (p < 0.001), 2D laparoscopy (p = 0.003), operative time (p < 0.001), estimated blood loss (p < 0.001), drainage (p < 0.001), specimen size (p = 0.011), conversions (p = 0.002), complications (p = 0.019), and hospital stay (p < 0.001). After adjustment for patient, surgical, and tumor characteristics, risk factors associated with prolonged LOS in the multivariate analysis were specimen size > 9 cm (OR:13.03, p = 0.005), surgery on Thursday or Friday (OR:6.92, p = 0.001), estimated blood loss ≥ 60 ml (OR:6.22, p = 0.021), and drainage (OR:5.29, p = 0.005). Prolonged length of stay after LTLA was associated with specimen size > 9 cm, operating on Thursday or Friday, estimated blood loss ≥ 60 mL, and drainage.

Transperitoneal laparoscopic surgery in large adrenal masses

INTRODUCTION

The laparoscopic adrenalectomy (LA) has become the gold standard since the transperitoneal laparoscopic approach was first reported.

AIM

To evaluate the applicability, safety and short-term results of laparoscopic surgery in adrenal masses over 6 cm.

MATERIAL AND METHODS

Demographic data, hormonal activities, imaging modalities, operative findings, operation time, conversion rates, complications, duration of hospital stay and histopathologic results of 128 patients who underwent laparoscopic adrenalectomy were evaluated retrospectively. Patients included in the learning curve (n = 23), robotic surgery cases (n = 15) and patients with suspected metastasis (n = 4) were excluded from the study. Six cm mass size was taken as a reference and two groups were formed (group 1: < 6 cm, group 2: ≥ 6 cm). The results of the two groups were compared.

RESULTS

There were 64 cases in group 1 and 22 cases in group 2. Functional mass ratio and mass sides were similar between the groups (p = 0.30 and p = 0.17, respectively). The mean mass size in group 1 was 36.4 ±11.2 mm and in group 2 82.4 ±15.5 mm. The conversion rate was similar between the two groups (p = 0.18). The duration of surgery was 135.5 ±8.29 min in group 1, 177.0 ±14.9 min in group 2 (p = 0.014). Morbidity and lengths of hospital stay were similar (p = 0.76, p = 0.34 respectively). Adrenocortical carcinoma was detected in three cases in group 1, which were completed laparoscopically, and in two cases in group 2, which were converted to open surgery (p = 0.46).

CONCLUSIONS

Although open surgery is still recommended in the guidelines, studies are now being carried out to ensure that laparoscopy can be safely performed on masses over 6 cm. There was no difference between short-term follow-up and histopathologic results in our study.