Current trends in surgical approach and outcomes following pituitary tumor resection

The State of Machine Learning in Outcomes Prediction of Transsphenoidal Surgery: A Systematic Review

The purpose of this analysis is to assess the use of machine learning (ML) algorithms in the prediction of postoperative outcomes, including complications, recurrence, and death in transsphenoidal surgery. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we systematically reviewed all papers that used at least one ML algorithm to predict outcomes after transsphenoidal surgery. We searched Scopus, PubMed, and Web of Science databases for studies published prior to May 12, 2021. We identified 13 studies enrolling 5,048 patients. We extracted the general characteristics of each study; the sensitivity, specificity, area under the curve (AUC) of the ML models developed as well as the features identified as important by the ML models. We identified 12 studies with 5,048 patients that included ML algorithms for adenomas, three with 1807 patients specifically for acromegaly, and five with 2105 patients specifically for Cushing's disease. Nearly all were single-institution studies. The studies used a heterogeneous mix of ML algorithms and features to build predictive models. All papers reported an AUC greater than 0.7, which indicates clinical utility. ML algorithms have the potential to predict postoperative outcomes of transsphenoidal surgery and can improve patient care. Ensemble algorithms and neural networks were often top performers when compared with other ML algorithms. Biochemical and preoperative features were most likely to be selected as important by ML models. Inexplicability remains a challenge, but algorithms such as local interpretable model-agnostic explanation or Shapley value can increase explainability of ML algorithms. Our analysis shows that ML algorithms have the potential to greatly assist surgeons in clinical decision making.

Descriptive surgical epidemiology of pituitary adenomas for a Hispanic population in Puerto Rico

Background

Demographics and socioeconomic variables for patients with pituitary adenomas have been reported in the past. However, these studies included operated and nonoperated patients, in addition to microprolactinomas frequently diagnosed in women, revealing an elevated incidence among females. This study aimed to analyze the surgical incidence of pituitary adenomas for an adult Hispanic population in Puerto Rico over 6 years.

Methods

A retrospective and descriptive study was performed to investigate pituitary adenoma surgical incidence (per 100,000 people) among surgically treated pituitary adenomas in an adult (18 years or more) Puerto Rico Hispanic population. All new patients diagnosed with pituitary adenomas who underwent surgery at the Puerto Rico Medical Center between 2017 and 2022 were scrutinized. Inclusion criteria required a histopathological diagnosis of pituitary adenoma. Previously operated cases and non-Hispanic patients were excluded from the study. Patient characteristics were collected, along with the type of surgical treatment, tumor size, and secretory status.

Results

The analysis included 143 patients operated on for pituitary adenomas. Of these, 75 (52%) patients were male, and 68 (48%) were female. The median age of the patients was 56 years (range: 18-85). The average annual surgical incidence of adult Hispanic patients with pituitary adenomas was 0.73 surgeries/100,000 people. About 79% of the patients had non-functioning pituitary adenomas. About 94% of the patients were operated on using transsphenoidal surgery.

Conclusion

There was no sex predominance for surgical-treated pituitary adenomas in Puerto Rico. The surgical incidence for adult pituitary adenoma remained stable between 2017 and 2022.

Cost-Effectiveness of Routine Type and Screens in Select Endonasal Skull Base Surgeries

Objective The study aimed to evaluate the cost-effectiveness of obtaining preoperative type and screens (T/S) for common endonasal skull base procedures, and determine patient and hospital factors associated with receiving blood transfusions.

Study Design Retrospective database analysis of the 2006 to 2015 National (nationwide) Inpatient Sample and cost-effectiveness analysis.

Main Outcome Measures Multivariate regression analysis was used to identify factors associated with transfusions. A cost-effectiveness analysis was then performed to determine the incremental cost-effectiveness ratio (ICER) of obtaining preoperative T/S to prevent an emergency-release transfusion (ERT), with a willingness-to-pay threshold of $1,500.

Results A total of 93,105 cases were identified with an overall transfusion rate of 1.89%. On multivariate modeling, statistically significant factors associated with transfusion included nonelective admission (odds ratio [OR]: 2.32; 95% confidence interval [CI]: 1.78–3.02), anemia (OR: 4.42; 95% CI: 3.35–5.83), coagulopathy (OR: 4.72; 95% CI: 2.94–7.57), diabetes (OR: 1.45; 95% CI: 1.14–1.84), liver disease (OR: 2.37; 95% CI: 1.27–4.43), pulmonary circulation disorders (OR: 3.28; 95% CI: 1.71–6.29), and metastatic cancer (OR: 5.85; 95% CI: 2.63–13.0; p < 0.01 for all). The ICER of preoperative T/S was $3,576 per ERT prevented. One-way sensitivity analysis demonstrated that the risk of transfusion should exceed 4.12% to justify preoperative T/S.

Conclusion Routine preoperative T/S does not represent a cost-effective practice for these surgeries using nationally representative data. A selective T/S policy for high-risk patients may reduce costs.

Transsphenoidal pituitary adenoma resection: do early post-operative cortisol levels predict permanent long-term hypocortisolism?

Transsphenoidal surgery provides a minimal invasive treatment for pituitary adenoma. Our aim is to evaluate the endocrinological outcomes after adenoma resection focusing on the corticotroph function, and to identify prognostic factors for an impaired hypothalamic–pituitary–adrenal-axis function (HPA) and the reliability of postoperative early morning serum cortisol measurements. We performed a retrospective analysis of all patients treated for pituitary adenoma from April 2006 to January 2019 in our neurosurgical department. Pituitary function was assessed pre- and postoperatively as well as at 6 weeks to 12 weeks and at 1-year follow-up. Two hundred eleven patients were included. Nine percent of the patients recovered from a preoperative adrenal insufficiency, 10.4% developed a new need for hormone substitution, and a long-term deficiency of the hypothalamic–pituitary–adrenal-axis was observed in 30.9%. Cortisol measurements 5 days after surgery had a lower area under the curve (AUC) than cortisol levels detected after 6 to 12 weeks (AUC 0.740 vs. AUC 0.808) in predicting an intact corticotrope function. The cut-off value determined for cortisol measured after 6 weeks was 6.95 µg/dl (sensitivity of 94%, specificity of 68%). Postoperative early morning cortisol levels seem to be less sensitive and specific in predicting long-term corticotroph function than measurements after 6 weeks and 1 year, emphasizing the importance of endocrine follow-up testing.

The Influence of Hospital Volume on the Outcomes of Nasopharyngeal, Sinonasal, and Skull-Base Tumors: A Systematic Review of the Literature

Objective: The center of excellence model of health care hypothesizes that increased volume in a specialized center will lead to better and more affordable care. We sought to characterize the volume-outcome data for surgically treated sinonasal and skull base tumors and (chemo) radiation-treated nasopharyngeal malignancy.

Design:  Systematic review of the literature.

Setting: This review included national database and multi-institutional studies published between 1990 and 2019.

Participants: PubMed was interrogated for keywords “hospital volume,” “facility volume,” and outcomes for “Nasopharyngeal carcinoma,” “Sinonasal carcinomas,” “Pituitary Tumors,” “Acoustic Neuromas,” “Chordomas,” and “Skull Base Tumors” to identify studies. Single-institution studies and self-reported surveys were excluded.

Main outcome measures: The main outcome of interest in malignant pathologies was survival; and in benign pathologies it was treatment-related complications.

Results: A total of 20 studies met inclusion criteria. The average number of patients per study was 4,052, and ranged from 394 to 9,950 patients. Six of seven studies on malignant pathology demonstrated improved survival with treatment in high volume centers and one showed no association with survival. Ten of thirteen studies on benign disease showed reduced risk of complications, while one study demonstrated both an increased and decreased association of complications. Two studies showed no volume-outcome associations.

Conclusion: This systematic review demonstrates that a positive volume–outcome relationship exists for most pathologies of the skull base, with some exceptions. The relative dearth of literature supports further research to understand the effect of centralization of care on treatment outcomes.

Systematic review and network meta-analysis assess the comparative efficacy and safety of transsphenoidal surgery for pituitary tumor

To quantitatively synthesize the comparative efficacy and safety of the most common surgical approaches including endonasal transsphenoidal endoscopic surgery (ETES), sublabial transsphenoidal microsurgery (STMS) and endonasal transsphenoidal microsurgery (ETMS) for all kinds of pituitary tumors. This systematic review and network meta-analysis was performed on randomized controlled trials (RCTs) and comparison studies from databases of Pubmed, EMBASE, and the Cochrane library. We selected the rate of gross complete resection as our primary outcome of efficacy. And the incidence of all complications, cerebrospinal fluid (CSF) leak, diabetes insipidus, nasal septal perforation, death, and bleeding were designed as our primary outcomes of safety. Twenty-seven studies with 2618 patients were included in this network meta-analysis. On efficacy, there was no statistical difference among the three methods including ETES, STMS, and ETMS. As for safety, results indicated that the incidence of total complications of STMS (OR = 4.74; 95% CI 1.03, 40.14) is significantly superior to ETES. And the incidence of diabetes insipidus of ETMS (OR = 2.21; 95% CI 1.31, 3.81) was significantly superior to that of ETES. Besides, there was no statistical difference in the other complications including CSF leak, nasal septal perforation, death, and bleeding. We clarified the overpraise of the efficacy of endoscopy especially the endonasal transsphenoidal approach, and verified that all the approaches owned similar efficacy. Moreover, we recommended the endoscopy to be the first choice for pituitary tumors, because it demonstrated the best safety.

Risk factors associated with the surgical management of craniopharyngiomas in pediatric patients: analysis of 1961 patients from a national registry database

OBJECTIVE

Patient demographic characteristics, hospital volume, and admission status have been shown to impact surgical outcomes of sellar region tumors in adults; however, the data available following the resection of craniopharyngiomas in the pediatric population remain limited. The authors sought to identify potential risk factors associated with outcomes following surgical management of pediatric craniopharyngiomas.

METHODS

The Nationwide Inpatient Sample database and Kids' Inpatient Database were analyzed to include admissions for pediatric patients (≤ 18 years) who underwent a transcranial or transsphenoidal craniotomy for resection of a craniopharyngioma. Patient-level factors, including age, race, comorbidities, and insurance type, as well as hospital factors were collected. Outcomes analyzed included mortality rate, endocrine and nonendocrine complications, hospital charges, and length of stay. A multivariate model controlling for variables analyzed was constructed to examine significant independent risk factors.

RESULTS

Between 2000 and 2011, 1961 pediatric patients were identified who underwent a transcranial (71.2%) or a transsphenoidal (28.8%) craniotomy for resection of a craniopharyngioma. A major predilection for age was observed with the selection of a transcranial (23.4% in < 7-year-olds, 28.1% in 7- to 12-year-olds, and 19.7% in 13- to 18-year-olds) versus transphenoidal (2.9% in < 7-year-olds, 7.4% in 7- to 12-year-olds, and 18.4% in 13- to 18-year-olds) approach. No significant outcomes were associated with a particular surgical approach, except that 7- to 12-year-old patients had a higher risk of nonendocrine complications (relative risk [RR] 2.42, 95% CI 1.04–5.65, p = 0.04) with the transsphenoidal approach when compared with 13- to 18-year-old patients. The overall inpatient mortality rate was 0.5% and the most common postoperative complication was diabetes insipidus (64.2%). There were no independent factors associated with inpatient mortality rates and no significant differences in outcomes among groups based on sex and race. The average length of stay was 11.8 days, and the mean hospital charge was $116,5 22. Hospitals with medium and large bed capacity were protective against nonendocrine complications (RR 0.53, 95% CI 0.3–0.93, p = 0.03 [medium]; RR 0.45, 95% CI 0.25–0.8, p < 0.01 [large]) and total complications (RR 0.73, 95% CI 0.55–0.97, p = 0.03 [medium]; RR 0.68, 95% CI 0.51–0.9, p < 0.01 [large]) when compared with hospitals with small bed capacity (< 200 beds). Patients admitted to rural hospitals had an increased risk for nonendocrine complications (RR 2.56, 95% CI 1.11–5.9, p = 0.03). The presence of one or more medical comorbidities increased the risk of higher total complications (RR 1.38, 95% CI 1.14–1.68), p < 0.01 [1 comorbidity]; RR 2.37, 95% CI 1.98–2.84, p < 0.01 [≥ 2 comorbidities]) and higher total hospital charges (RR 2.9, 95% CI 1.08–7.81, p = 0.04 [1 comorbidity]; RR 9.1, 95% CI 3.74–22.12, p < 0.01 [≥ 2 comorbidities]).

CONCLUSIONS

This analysis identified patient age, comorbidities, insurance type, hospital bed capacity, and rural or nonteaching hospital status as independent risk factors for postoperative complications and/or increased hospital charges in pediatric patients with craniopharyngioma. Transsphenoidal surgery in younger patients with craniopharyngioma was a risk factor for nonendocrine complications.

Complication Avoidance in Endoscopic Skull Base Surgery

Endoscopic endonasal approaches to the skull base pathology have developed and evolved dramatically over the past 2 decades, particularly with collaboration between neurosurgery and otolaryngology physicians. These advances have increased significantly the use of such approaches beyond just resection of pituitary adenomas, including a variety of skull base pathologies. As the field has evolved, so has our understanding of the complications accompanying endoscopic skull base surgery, as well as techniques to both avoid and manage these complications. These are discussed here.

Pediatric pituitary resection: characterizing surgical approaches and complications

BACKGROUND

Although there has been extensive study evaluating adult pituitary surgery, there has been scant analysis among children. Our objective was to evaluate a population-based resource to characterize nationwide trends in surgical approach, hospital stay, and complications among children undergoing pituitary surgery.

METHODS

The Kids' Inpatient-Database (KID) files (2009/2012) were evaluated for pituitary gland excisions. Procedure, patient demographics, length of inpatient stay, inpatient costs, hospital setting, and surgical complications were analyzed.

RESULTS

A weighted incidence of 1071 cases were analyzed; the majority (77.6%) underwent transsphenoidal resections. These patients had significantly decreased hospital costs and lengths of stay. Patients undergoing transfrontal approaches had significantly greater rates of postoperative diabetes insipidus (DI) (66.5%), panhypopituitarism (38.8%), hydrocephalus, and visual deficits. Among transsphenoidal patients, males had greater rates of postoperative hydrocephalus (5.5%) and panhypopituitarism (17.5%) than females, and patients ≤10 years old had greater rates of these 2 complications (14.5%, 19.4%, respectively) as well as DI (61.3%).

CONCLUSION

A greater proportion of children undergo transfrontal approaches for pituitary lesions than in their adult counterparts. This difference may harbor a potential to influence future sellar resection approaches in children toward a transsphenoidal operation when surgically feasible. Patients undergoing transfrontal procedures have greater risks for many intraoperative and postoperative complications relative to individuals undergoing transsphenoidal resections. Among patients undergoing transsphenoidal approaches, males had significantly greater rates of postoperative hydrocephalus and panhypopituitarism, and younger children had greater rates of postoperative DI, hydrocephalus, and panhypopituitarism. These data reinforce the need for greater vigilance in the postoperative care of younger children undergoing transsphenoidal surgery.

Predictors of 30-day morbidity and mortality in transnasal microscopic pituitary tumor excision

BACKGROUND

There is a lack of population-based, multi-institutional analyses of factors associated with morbidity and mortality following pituitary tumor excision.

METHODS

The American College of Surgeons National Surgical Quality Improvement Project files were used to compile information on patients that had undergone transnasal microscopic pituitary tumor resection from 2006 to 2012. Patient demographics, comorbidities, operative characteristics, and morbidity and mortality in the 30 days following surgery were included. Multivariate logistic regression was used for categorical variables and multivariate linear regression was used for continuous variables to evaluate factors leading to adverse events.

RESULTS

A total of 658 patients were included, of which 58 (8.81%) experienced a complication, reoperation or death in the 30 days following surgery. The most common complications were reoperation (3.37%), followed by unplanned reintubation (1.99%), urinary tract infection (1.68%), and transfusion (1.68%). Predictors of any complication, reoperation, or death include preoperative sepsis (odds ratio [OR] = 7.596) and lower preoperative serum albumin (OR = 6.667). Younger age predicted surgical complications (OR = 1.105). Predictors of medical complications include higher body mass index (OR = 1.112), chronic steroid use (OR = 6.568), preoperative sepsis (OR = 15.297), and lower preoperative serum hematocrit (OR = 1.225). Predictors of increased total length of hospital stay were older age (β = 0.146), higher body mass index (β = 0.188), chronic steroid use (β = 0.142), preoperative sepsis (β = 0.489), and lower preoperative serum albumin (β = -0.213).

CONCLUSION

Although adverse events following pituitary tumor excision are low, awareness of factors associated with morbidity and mortality in the early postoperative period may allow for improved patient monitoring and outcomes.