Thirty-day unplanned hospital readmission in ovarian cancer patients undergoing primary or interval cytoreductive surgery: systematic literature review

Factors associated with emergency room readmission after elective surgery for ovarian carcinoma

BACKGROUND

Hospital readmission is a quality metric of hospital care and has been studied in ovarian carcinoma, but its evaluation has several limitations. Also, emergency room (ER) readmission is considered an adverse effect because it represents patient costs. Therefore, our objective was to determine the rate of ER readmission, its causes, and associated factors.

METHODS

A retrospective study of 592 patients with ovarian carcinoma who underwent upfront surgery, neoadjuvant therapy, or surgery for recurrent disease. An analysis of factors associated with ER readmission, hospital readmission, and surgical complications was performed, including multivariate analysis to assess for case-mix factors.

RESULTS

Of 592 patients, the median age was 51 years, and the predominant type of treatment was the neoadjuvant approach (52.9%); 46% underwent upfront surgeries and six surgeries for recurrence. The ratio to ER readmission was 11.8% (70 patients), of whom 12 patients were admitted more than once. The factors associated with ER readmission were prolonged surgery, intraoperative bleeding, extended hospital stay, the time of the day when the surgery was performed, and post-surgical complications. The hospital readmissions were 4.2%, and the overall morbidity was 17.6%. In the multivariate analysis, the only factor associated with ER readmission was the presence of surgical complications (OR = 39.01). The factors independently associated with hospital readmission were the entrance to the intensive care unit (OR = 1.37), the presence of surgical complications (OR = 2.85), and ER readmission (OR = 1.45).

CONCLUSION

ER readmission is an adverse event representing the presence of symptoms/complications in patients. Evaluating the ER readmission independently of the readmission to the hospital is critical because it will allow modifying medical care behaviors to prevent patients from unnecessarily returning to the hospital after a hospital discharge to manage preventable medical problems.

TRIAL REGISTRATION

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Prospective evaluation of an enhanced recovery after surgery (ERAS) pathway in a Norwegian cohort of patients with suspected or advanced ovarian cancer

OBJECTIVE

This prospective cohort study evaluated the introduction of an enhanced recovery after surgery (ERAS) pathway in a tertiary gynecologic oncology referral center. Compliance and clinical outcomes were studied in two separate surgical cohorts.

METHODS

Patients undergoing laparotomy for suspected or verified advanced ovarian cancer at Oslo University Hospital were prospectively included in a pre- and post-implementation cohort. A priori, patients were stratified into: cohort 1, patients planned for surgery of advanced disease; and cohort 2, patients undergoing surgery for suspicious pelvic tumor. Baseline characteristics, adherence to the pathway, and clinical outcomes were assessed.

RESULTS

Of the 439 included patients, 235 (54%) underwent surgery for advanced ovarian cancer in cohort 1 and 204 (46%) in cohort 2. In cohort 1, 53% of the patients underwent surgery with an intermediate/high Aletti complexity score. Post-ERAS, median fasting times for solids (13.1 hours post-ERAS vs 16.0 hours pre-ERAS, p<0.001) and fluids (3.7 hours post-ERAS vs 11.0 hours pre-ERAS, p<0.001) were significantly reduced. Peri-operative fluid management varied less and was reduced from median 15.8 mL/kg/hour (IQR 10.8-22.5) to 11.5 mL/kg/hour (IQR 9.0-15.4) (p<0.001). In cohort 2 only there was a statistically significant reduction in length of stay (mean (SD) 4.3±1.5 post-ERAS vs 4.6±1.2 pre-ERAS, p=0.026). Despite stable readmission rates, there were significantly more serious complications reported in cohort 1 post-ERAS.

CONCLUSIONS

ERAS increased adherence to current standards in peri-operative management with significant reduction in fasting times for both solids and fluids, and peri-operative fluid administration. Length of stay was reduced in patients with suspicious pelvic tumor. Despite serious complications being common in patients with advanced disease undergoing debulking surgery, a causal relationship with the ERAS protocol could not be established. Implementing ERAS and continuous performance auditing are crucial to advancing peri-operative care of patients with ovarian cancer.

A single institution's experience with minimally invasive surgery for ovarian cancer, and a systematic meta-analysis of the literature

BACKGROUND

This study assesses the feasibility of minimally invasive surgery (MIS) for well-selected epithelial ovarian cancer (EOC) patients.

METHODS

We performed a review of data prospectively collected from a single center from 2017 to 2022. Only patients with histologically confirmed EOC, with a tumor diameter of less than 10 cm, were eligible. We also performed a meta-analysis of similar studies comparing the outcomes of laparoscopy and laparotomy. We used MINORS (Methodological Index for Non-Randomized Studies) to assess the risk of bias and calculated the odds ratio or mean difference.

RESULTS

Eighteen patients were included; 13 in re-staging group, four in PDS group, and one in IDS group. All achieved complete cytoreduction. One case was converted to laparotomy. The median number of removed pelvic lymph nodes was 25 (range 16-34), and 32 (range 19-44) for para-aortic nodes. There were two (15.4%) intraoperative urinary tract injuries. The median follow-up was 35 months (range 1-53). Recurrence was observed in one case (7.7%). Thirteen articles for early-stage ovarian cancer were included in our meta-analysis. Analysis of the pooled results found that MIS had a higher frequency of spillage (OR, 2.15; 95% CI 1.27-3.64). No differences were observed in recurrence, complications, or up-staging.

CONCLUSIONS

Our experience supports the possibility of conducting MIS for EOC in well-selected patients. Except for spillage, our meta-analysis findings are consistent with previous reports, the majority of which were also retrospective. Ultimately, randomized clinical trials will be needed to authenticate the safety.

Beyond post-operative readmissions: analysis of the impact of unplanned readmissions during primary treatment of advanced-stage epithelial ovarian cancer on long-term oncology outcome

BACKGROUND

Multiple studies have assessed post-operative readmissions in advanced ovarian cancer.

OBJECTIVE

To evaluate all unplanned readmissions during the primary treatment period of advanced epithelial ovarian cancer, and the impact of readmission on progression-free survival.

METHODS

This was a single institution retrospective study from January 2008 to October 2018. Χ²/Fisher's exact and t-test, or Kruskal-Wallis test were used. Multivariable Cox proportional hazard models were used to assess the effect of covariates in progression-free survival analysis.

RESULTS

A total of 484 patients (279 primary cytoreductive surgery, 205 neoadjuvant chemotherapy) were analyzed. In total, 272 of 484 (56%; 37% primary cytoreductive surgery, 32% neoadjuvant chemotherapy, p=0.29) patients were readmitted during the primary treatment period. Overall, 42.3% of the readmissions were surgery related, 47.8% were chemotherapy related, and 59.6% were cancer related but not related to surgery or chemotherapy, and each readmission could qualify for more than one reason. Readmitted patients had a higher rate of chronic kidney disease (4.1% vs 1.0%, p=0.038). Post-operative, chemotherapy, and cancer-related readmissions were similar between the two groups. However, the percentage of inpatient treatment days due to unplanned readmission was twice as high for primary cytoreductive surgery at 2.2% vs 1.3% for neoadjuvant chemotherapy (p<0.001). Despite longer readmissions in the primary cytoreductive surgery group, Cox regression analysis demonstrated that readmissions did not affect progression-free survival (HR=1.22, 95% CI 0.98 to 1.51; p=0.08). Primary cytoreductive surgery, higher modified Frailty Index, grade 3 disease, and optimal cytoreduction were associated with longer progression-free survival.

CONCLUSIONS

In this study, 35% of the women with advanced ovarian cancer had at least one unplanned readmission during the entire treatment time. Patients treated by primary cytoreductive surgery spent more days during readmission than those with neoadjuvant chemotherapy. Readmissions did not affect progression-free survival and may not be valuable as a quality metric.

Factors Predicting Surgical Effort Using Explainable Artificial Intelligence in Advanced Stage Epithelial Ovarian Cancer

(1) Background: Surgical cytoreduction for epithelial ovarian cancer (EOC) is a complex procedure. Encompassed within the performance skills to achieve surgical precision, intra-operative surgical decision-making remains a core feature. The use of eXplainable Artificial Intelligence (XAI) could potentially interpret the influence of human factors on the surgical effort for the cytoreductive outcome in question; (2) Methods: The retrospective cohort study evaluated 560 consecutive EOC patients who underwent cytoreductive surgery between January 2014 and December 2019 in a single public institution. The eXtreme Gradient Boosting (XGBoost) and Deep Neural Network (DNN) algorithms were employed to develop the predictive model, including patient- and operation-specific features, and novel features reflecting human factors in surgical heuristics. The precision, recall, F1 score, and area under curve (AUC) were compared between both training algorithms. The SHapley Additive exPlanations (SHAP) framework was used to provide global and local explainability for the predictive model; (3) Results: A surgical complexity score (SCS) cut-off value of five was calculated using a Receiver Operator Characteristic (ROC) curve, above which the probability of incomplete cytoreduction was more likely (area under the curve [AUC] = 0.644; 95% confidence interval [CI] = 0.598−0.69; sensitivity and specificity 34.1%, 86.5%, respectively; p = 0.000). The XGBoost outperformed the DNN assessment for the prediction of the above threshold surgical effort outcome (AUC = 0.77; 95% [CI] 0.69−0.85; p < 0.05 vs. AUC 0.739; 95% [CI] 0.655−0.823; p < 0.95). We identified “turning points” that demonstrated a clear preference towards above the given cut-off level of surgical effort; in consultant surgeons with <12 years of experience, age <53 years old, who, when attempting primary cytoreductive surgery, recorded the presence of ascites, an Intraoperative Mapping of Ovarian Cancer score >4, and a Peritoneal Carcinomatosis Index >7, in a surgical environment with the optimization of infrastructural support. (4) Conclusions: Using XAI, we explain how intra-operative decisions may consider human factors during EOC cytoreduction alongside factual knowledge, to maximize the magnitude of the selected trade-off in effort. XAI techniques are critical for a better understanding of Artificial Intelligence frameworks, and to enhance their incorporation in medical applications.

Neoadjuvant chemotherapy does not disproportionately influence post-operative complication rates or time to chemotherapy in obese patients with advanced-stage ovarian cancer

OBJECTIVES

To determine whether neoadjuvant chemotherapy (NACT) disproportionately benefits obese patients.

METHODS

Data were collected from stage IIIC-IV ovarian cancer patients treated between 01/2010-07/2015. We performed univariate/multivariate logistic regression analyses with post-operative infection, readmission, any postoperative complication, and time to chemotherapy as outcomes. An interaction term was included in models, to determine if the effect of NACT on post-operative complications was influenced by obesity status.

RESULTS

Of 507 patients, 115 (22.6%) were obese and 392 (77.3%) were non-obese (obese defined as BMI ≥30). Among obese patients undergoing primary debulking surgery (PDS) vs. NACT, rates of postoperative infection were 42.9% vs. 30.8% (p = 0.12), 30-day readmission 30.2% vs. 11.5% (p < 0.02), and any post-operative complication were 44.4% vs 30.8% (p = 0.133). Among non-obese patients undergoing PDS vs. NACT, rates of post-operative infection were 20.0% vs. 12.9% (p = 0.057), 30-day readmission 16.9% vs. 9.2% (p = 0.02), and any post-operative complication were 19.4% vs 28% (p = 0.044). Obesity was associated with post-operative infection (OR 2.3; 95%CI 1.22-4.33), 30-day readmission/reoperation (OR 2.27; 95%CI 1.08-3.21) and the development of any post-operative complication (OR 2.1; CI 1.13-3.74). However, there was not a significant interaction between obesity and NACT in any of the models predicting post-operative complications.

CONCLUSIONS

The decision to use NACT should not be predicated on obesity alone, as the reduction in post-operative complications in obese patients is similar to non-obese patients.

Value of pre-existent bacterial colonization in patients with advanced/relapsed ovarian neoplasms undergoing cytoreductive surgery: a multicenter observational study (BONSAI)

OBJECTIVE

As an increasing number of patients with advanced/relapsed ovarian cancer need extensive cytoreductive procedures, there is an increasing number of complex cases collected in accredited tertiary cancer centers. With nosocomial infections and bacterial colonizations being a significant challenge in these patient cohorts, we aimed to evaluate the risk such infections pose to surgical outcome.

METHODS

Prospective assessment of pathological bacterial colonization (vaginal, umbilical/groin, intraperitoneal, urine, oral/nose cavity) in patients who underwent open cytoreductive surgery for advanced/relapsed ovarian cancer in two large European tertiary referral centers for gynecologic malignancies. We recruited patients at initial diagnosis with International Federation of Gynecology and Obstetrics (FIGO) stage III and IV ovarian cancer and patients undergoing surgery for relapse. Swabs or cultures were taken from the following sites: vagina, groin and/or umbilicus, urine, intraperitoneal, mouth and/or nose. Only evidence of pathogenic bacteria was considered positive for bacterial colonization.

RESULTS

A total of 172 primary advanced (70.9%) or relapsed (29.1%) ovarian cancer patients were included; 63.4% of them had received chemotherapy±additional targeted agents (16.3%) by the time of cytoreduction. 39.5% of the patients had a long-term vascular access line in situ. A bowel resection was performed in 44.8% and a splenectomy in 16.3% of the patients. Predefined surgical morbidity and mortality were 22.3% and 0%, respectively. Forty-one patients (23.8%) screened positive for pathogenic bacterial colonization with the presence of long-term intravenous access as the only independent risk factor identified (OR 2.34; 95% CI 1.05 to 5.34; p=0.04). Type of systemic treatments, previous bowel resections, previous hospitalizations, and patient demographics did not appear to significantly impact the risk of bacterial colonization. Furthermore, pathogenic bacterial colonization was shown to have no significant effect on peri-operative infection-related complications such as abscesses, wound infection, pneumonia, relaparotomy, or anastomotic leak.

CONCLUSIONS

A total of 24% of patients undergoing cytoreductive surgery for ovarian cancer were confirmed positive for pathogenic bacterial colonization. The presence of long-term intravenous access was identified as the only significant risk factor for that, however the presence of pathogenic bacterial colonization per se did not seem to adversely affect outcome of cytoreductive effort or increase perioperative infection related complications.

Readmissions after ovarian cancer cytoreduction surgery: The first 30 days and beyond

BACKGROUND AND OBJECTIVES

Postoperative readmissions are often used to assess quality of surgical care. This study compared 30-day vs 31- to 90-day readmission following surgery for ovarian, fallopian tube, or primary peritoneal cancer.

METHODS

This retrospective study of the 2010-2015 Nationwide Readmissions Database characterized 90-day readmissions following cytoreductive surgery for these cancers. Each patient's first postoperative hospitalization was included. Univariate analysis compared patient demographics and reasons for readmission. Multivariable regression identified independent predictors of readmission.

RESULTS

Of an estimated 76 652 patients, 10 264 (13.4%) were readmitted within 30 days, and 6942 (9.1%) between 31 and 90 days. The 30-day readmissions were more frequently associated with postoperative infection, while 31- to 90-day readmissions were more frequently associated with renal or hematologic diagnoses. Predictors of any 90-day readmission included index hospitalization longer than 7 days (adjusted odds ratio (AOR) 1.61 [1.48-1.75], P < .001), extended surgical procedure (AOR 1.41 [1.30-1.53], P < .001), pulmonary circulation disorder (AOR = 1.34 [1.13-1.60], P = .001), and diabetes mellitus (AOR = 1.12 [1.02-1.24], P = .020).

CONCLUSIONS

Readmission rates remain high during the 31- to 90-day postoperative period in ovarian cancer patients, although these readmissions are less frequently related to postoperative complications. Prospective study is merited to optimize surveillance beyond the initial 30 days after ovarian cancer surgery.

National trends in bowel and upper abdominal procedures in ovarian cancer surgery

OBJECTIVES

In the United States, trends in the initial treatment approach for ovarian cancer reflect a shift in paradigm toward the increased use of neoadjuvant chemotherapy and interval cytoreductive surgery. The aim of this study was to evaluate the trends in surgical cytoreductive procedures in ovarian cancer patients who underwent either primary or interval cytoreductive surgery.

METHODS

This retrospective, population-based study examined patients with stage III/IV ovarian cancer diagnosed between January 2000 and December 2013 identified using SEER-Medicare. Small or large bowel resection, ostomy creation, and upper abdominal procedures were identified using relevant billing codes and compared over time. A 1:1 primary and interval cytoreductive propensity matched cohort was created using demographic and clinical variables. 30-day complications and the use of acute care services were compared.

RESULTS

A total of 5417 women were identified. 34% underwent bowel resections, 16% ostomy creation, and 8% upper abdominal procedures. There was an increase in bowel resections and upper abdominal procedures from 2000 to 2013 in patients who underwent primary cytoreductive surgery. Compared with patients who received primary cytoreduction, patients who underwent interval cytoreductive surgery were less likely to undergo bowel resection (OR=0.50; 95% CI [0.41, 0.61]) or ostomy creation (OR=0.48; 95% CI [0.42, 0.56]). Upper abdominal procedures did not differ between groups. For patients who underwent primary cytoreductive surgery, these procedures were associated with intensive care unit stay (4.6% vs <2%, P<0.01). In both primary and interval cytoreductive surgery patients, the receipt of bowel and upper abdominal procedures was associated with multiple 30-day postoperative complications and higher rates of readmission and emergency room visits.

CONCLUSIONS

The performance of upper abdominal procedures in ovarian cancer patients increased from 2000 to 2013. Interval cytoreductive surgery was associated with decreased likelihood of bowel surgery. In matched primary and interval cytoreductive surgery cohorts, the receipt of these procedures were associated with the increased likelihood of postoperative complications and use of acute care services.

Fragmentation of postoperative care after surgical management of ovarian cancer at 30 days and 90 days

BACKGROUND

Fragmentation of care, wherein a patient is discharged from an index hospital and undergoes an unexpected readmission to a nonindex hospital, is associated with increased risk of adverse outcomes. Fragmentation has not been well-characterized in ovarian cancer.

OBJECTIVE

The objective of this study was to assess risk factors and outcomes that are associated with fragmentation of care among women who undergo surgical treatment of ovarian cancer.

STUDY DESIGN

The Nationwide Readmission Database was used to identify all-cause 30-day and 90-day postoperative readmissions after surgical management of ovarian cancer from 2010-2014. Postoperative fragmentation was defined as readmission to a hospital other than the index hospital of the initial surgery. Multivariable regression analyses were used to identify predictors of fragmentation in both 30-day and 90-day readmissions. Similarly, multivariable models were developed to determine the association between fragmentation and death among women who were readmitted.

RESULTS

A total of 10,445 patients (13.3%) were readmitted at 30 days, and 14,124 patients (18.0%) were readmitted at 90 days. Of these, there was a 20.8% and 25.7% rate of postoperative care fragmentation for 30-day and 90-day readmissions, respectively. Patient risk factors that were associated with fragmented postoperative care included Medicare insurance, lower income quartiles, and nonroutine discharge to facility. Hospital factors that were associated with decreased risk of fragmentation included operation at a metropolitan teaching hospital and performance of extended procedures. Cost and length of stay for the readmission were similar among those who had fragmented and nonfragmented readmissions at both 30 and 90 days. Although there was no association between death and fragmentation for patients who were readmitted within 30 days (odds ratio, 1.19; 95% confidence interval, 0.93-1.51), patients who had a fragmented readmission at 90 days were 22% more likely to die than those who were readmitted at 90 days to their index hospital (odds ratio, 1.22; 95% confidence interval, 1.00-1.49).

CONCLUSION

Fragmentation of care is common in women with ovarian cancer who require postoperative readmission. Fragmented postoperative care is associated with an increased risk of death among women who are readmitted within 90 days of surgery.

Maximal-Effort Cytoreductive Surgery for Ovarian Cancer Patients with a High Tumor Burden: Variations in Practice and Impact on Outcome

BACKGROUND

This study aimed to compare the outcomes of two distinct patient populations treated within two neighboring UK cancer centers (A and B) for advanced epithelial ovarian cancer (EOC).

METHODS

A retrospective analysis of all new stages 3 and 4 EOC patients treated between January 2013 and December 2014 was performed. The Mayo Clinic surgical complexity score (SCS) was applied. Cox regression analysis identified the impact of treatment methods on survival.

RESULTS

The study identified 249 patients (127 at center A and 122 in centre B) without significant differences in International Federation of Gynecology and Obstetrics (FIGO) stage (FIGO 4, 29.7% at centers A and B), Eastern Cooperative Oncology Group (ECOG) performance status (ECOG < 2, 89.9% at centers A and B), or histology (serous type in 84.1% at centers A and B). The patients at center A were more likely to undergo surgery (87% vs 59.8%; p < 0.001). The types of chemotherapy and the patients receiving palliative treatment alone were equivalent between the two centers (3.6%). The median SCS was significantly higher at center A (9 vs 2; p < 0.001) with greater tumor burden (9 vs 6 abdominal fields involved; p < 0.001), longer median operation times (285 vs 155 min; p < 0.001), and longer hospital stays (9 vs 6 days; p < 0.001), but surgical morbidity and mortality were equivalent. The independent predictors of reduced overall survival (OS) were non-serous histology (hazard ratio [HR], 1.6; 95% confidence interval [CI] 1.04-2.61), ECOG higher than 2 (HR, 1.9; 95% CI 1.15-3.13), and palliation alone (HR, 3.43; 95% CI 1.51-7.81). Cytoreduction, of any timing, had an independent protective impact on OS compared with chemotherapy alone (HR, 0.31 for interval surgery and 0.39 for primary surgery), even after adjustment for other prognostic factors.

CONCLUSIONS

Incorporating surgery into the initial EOC management, even for those patients with a greater tumor burden and more disseminated disease, may require more complex procedures and more resources in terms of theater time and hospital stay, but seems to be associated with a significant prolongation of the patients overall survival compared with chemotherapy alone.