Minimally invasive surgery for early-stage ovarian cancer: Association between hospital surgical volume and short-term perioperative outcomes

Effect of surgical volume on short-term outcomes of cytoreductive surgery for advanced-stage ovarian cancer: A population-based study from the Dutch Gynecological Oncology Audit

OBJECTIVE

Despite lacking clinical data, the Dutch government is considering increasing the minimum annual surgical volume per center from twenty to fifty cytoreductive surgeries (CRS) for advanced-stage ovarian cancer (OC). This study aims to evaluate whether this increase is warranted.

METHODS

This population-based study included all CRS for FIGO-stage IIB-IVB OC registered in eighteen Dutch hospitals between 2019 and 2022. Short-term outcomes included result of CRS, length of stay, severe complications, 30-day mortality, time to adjuvant chemotherapy, and textbook outcome. Patients were stratified by annual volume: low-volume (nine hospitals, <25), medium-volume (four hospitals, 29-37), and high-volume (five hospitals, 54-84). Descriptive statistics and multilevel logistic regressions were used to assess the (case-mix adjusted) associations of surgical volume and outcomes.

RESULTS

A total of 1646 interval CRS (iCRS) and 789 primary CRS (pCRS) were included. No associations were found between surgical volume and different outcomes in the iCRS cohort. In the pCRS cohort, high-volume was associated with increased complete CRS rates (aOR 1.9, 95%-CI 1.2-3.1, p = 0.010). Furthermore, high-volume was associated with increased severe complication rates (aOR 2.3, 1.1-4.6, 95%-CI 1.3-4.2, p = 0.022) and prolonged length of stay (aOR 2.3, 95%-CI 1.3-4.2, p = 0.005). 30-day mortality, time to adjuvant chemotherapy, and textbook outcome were not associated with surgical volume in the pCRS cohort. Subgroup analyses (FIGO-stage IIIC-IVB) showed similar results. Various case-mix factors significantly impacted outcomes, warranting case-mix adjustment.

CONCLUSIONS

Our analyses do not support further centralization of iCRS for advanced-stage OC. High-volume was associated with higher complete pCRS, suggesting either a more accurate selection in these hospitals or a more aggressive approach. The higher completeness rates were at the expense of higher severe complications and prolonged admissions.

Laparoscopic Surgery for Ovarian Neoplasms - What is Possible, What is Useful?

The use of minimally invasive surgical techniques is becoming increasingly important in gynecologic oncology due to technical advances and the increasing level of surgical expertise. In addition to laparoscopic approaches for the treatment of benign neoplasms, minimally invasive surgical methods have also become established in some areas for treating gynecologic malignancies. For tumor entities such as endometrial and cervical carcinoma, there are conclusive studies emphasizing the role of laparoscopy in surgical therapy. By contrast, due to a lack of prospective data with survival analyses, no clear conclusions can be drawn on the significance of laparoscopy in the surgical treatment of ovarian carcinoma. However, some smaller, mostly retrospective case-control studies and cohort studies open the way for a discussion, positing the possibility that laparoscopic surgical procedures, particularly for early ovarian carcinoma, are technically feasible and of a quality equivalent to that of conventional longitudinal laparotomy, and may also be associated with lower perioperative morbidity. In this article we discuss the most important aspects of using minimally invasive surgical techniques for ovarian carcinoma based on the current literature. In particular we look at the relevance of laparoscopy as a primary approach for surgical staging of early ovarian carcinoma, and we evaluate the role of diagnostic laparoscopy in assessing the operability of advanced ovarian carcinoma.

Laparoscopic and Laparotomic Restaging in Patients With Apparent Stage I Epithelial Ovarian Cancer: A Comparison of Surgical and Oncological Outcomes

Objective

To assess the surgical and oncological outcomes of laparoscopic restaging compared with laparotomy for apparent early-stage epithelial ovarian cancer.

Methods

A retrospective chart review was undertaken of patients who underwent laparoscopic (laparoscopy group) or laparotomic (laparotomy group) restaging at the Peking Union Medical College Hospital, China, between January 2012 and December 2017. All patients had apparent stage I epithelial ovarian cancer that was incompletely staged at the initial surgery.

Results

A total of 157 patients were included, with 50 in the laparoscopy group and 107 in the laparotomy group. Baseline characteristics were similar between the groups. No cases were converted from laparoscopy to laparotomy. The laparoscopy group had a significantly shorter operating time (p<0.001), less estimated blood loss (p<0.001), and a shorter postoperative hospitalization duration (p<0.001) than the laparotomy group. Transfusions were required in only eight laparotomy patients. No significant differences in postoperative complications were observed between the two groups (p=0.55). Eighteen (11.5%) patients were upstaged to stage II or stage III after surgery. A total of 123 (78.3%) patients received postoperative platinum-based chemotherapy. During the follow-up period, 15 (9.6%) patients experienced disease recurrence, and 3 patients died of disease progression. Five-year disease-free survival (p = 0.242, log-rank test) and overall survival (p = 0.236, log-rank test) were not affected by the surgical approach.

Conclusions

Laparoscopic restaging showed more favorable operative outcomes than laparotomy. Surgical restaging via laparoscopy versus laparotomy was not associated with worse survival in women with apparent stage I epithelial ovarian cancer.

Association between hospital treatment volume and major complications in ovarian hyperstimulation syndrome

OBJECTIVE

An inverse relationship between hospital volume and adverse patient outcomes has been established for many conditions, but has not yet been examined in ovarian hyperstimulation syndrome (OHSS). Given the rarity of severe OHSS, but potential for high morbidity, this study aimed to elucidate the effect of hospital volume on inpatient OHSS-related complications.

METHODS

This is a retrospective observational study querying the National Inpatient Sample, 1/2001-12/2011. Study population was 11,878 patients with OHSS treated at 735 hospitals. Annualized hospital OHSS treatment volume was grouped as: low-volume (1 case/year), mid-volume (>1 but < 3.5 cases/year), and high-volume (≥3.5 cases/year). Main outcome measure was major complication rates stratified by hospital treatment volume, assessed by multinomial regression and binary logistic regression models.

RESULTS

A total of 2,415 (20.3%) patients were treated at low-volume centers, 5,023 (42.3%) at mid-volume centers, and 4,440 (37.4%) at high-volume centers. Patients treated at high-volume centers were more likely to be older and less comorbid with higher incomes and lower body mass index (P < 0.05). High-volume hospitals were more likely to be urban-teaching centers with large bed capacity (P < 0.001). Overall, 1,624 (13.7%) patients experienced a major complication during hospitalization. Patients treated at high-volume hospitals had lower rates of major complications (high: 11.0%, mid: 15.2%, low: 15.6%, P < 0.001). On multivariable analysis, treatment at high-volume hospitals was independently associated with a nearly 20% lower rate of major complications (odds ratio 0.82, 95% confidence interval 0.70-0.97, P = 0.021).

CONCLUSION

Our study suggests that higher hospital treatment volume for OHSS may be associated with improved outcomes.

Transvaginal Natural Orifice Transluminal Endoscopic Surgery for Surgical Staging of Early-Stage Ovarian Cancers: A Report of Two Cases

Surgical staging is essential in the management of ovarian cancers. This staging has traditionally been performed by laparotomy, but minimally invasive techniques are increasingly employed. Transvaginal natural orifice transluminal endoscopic surgery (vNOTES) is a promising technique in the field of gynecological oncology. We report 2 cases of vNOTES surgical staging for suspicious ovarian tumors. We operated on 2 patients aged of 81 and 62 years for low-grade serous ovarian carcinoma and ovarian cystadenofibroma, respectively. We performed surgical staging with a pure vNOTES technique for the first patient and used a hybrid approach for the second. No intraoperative or postoperative complications were observed. We suggest that vNOTES is a feasible and effective approach to surgically manage early-stage ovarian cancers.

Algorithm to Identify Incident Epithelial Ovarian Cancer Cases Using Claims Data

PURPOSE

To create an algorithm to identify incident epithelial ovarian cancer cases in claims-based data sets and evaluate performance of the algorithm using SEER-Medicare claims data.

METHODS

We created a five-step algorithm on the basis of clinical expertise to identify incident epithelial ovarian cancer cases using claims data for (1) ovarian cancer diagnosis, (2) receipt of platinum-based chemotherapy, (3) no claim for platinum-based chemotherapy but claim for tumor debulking surgery, (4) removed cases with nonplatinum chemotherapy, and (5) removed patients with prior claims with personal history of ovarian cancer code to exclude prevalent cases. We evaluated algorithm performance using SEER-Medicare claims data by creating four cohorts: incident epithelial ovarian cancer, a 5% random sample of cancer-free Medicare beneficiaries, a 5% random sample of incident nonovarian cancer, and prevalent ovarian cancer cases.

RESULTS

Using SEER tumor registry data as the gold standard, our algorithm correctly classified 89.9% of incident epithelial ovarian cancer cases (cohort n = 572) and almost 100% of cancer-free controls (n = 97,127), nonovarian cancer (n = 714), and prevalent ovarian cancer cases (n = 3,712). The overall algorithm sensitivity was 89.9%, the positive predictive value was 93.8%, and the specificity and negative predictive value were > 99.9%. Patients were more likely to be correctly classified as incident ovarian cancer if they had stage III or IV disease compared with early stage I or II disease (93.5% v 83.7%, P < .01), and grade 1-4 compared with unknown grade tumors (93.8% v 81.4%, P < .01).

CONCLUSION

Our algorithm correctly identified most incident epithelial ovarian cancer cases, especially those with advanced disease. This algorithm will facilitate research in other claims-based data sets where cancer registry data are unavailable.

Minimally Invasive Surgery and Surgical Volume-Specific Survival and Perioperative Outcome: Unmet Need for Evidence in Gynecologic Malignancy

This study examined the effect of hospital surgical volume on oncologic outcomes in minimally invasive surgery (MIS) for gynecologic malignancies. The objectives were to assess survival outcomes related to hospital surgical volume and to evaluate perioperative outcomes and examine non-gynecologic malignancies. Literature available from the PubMed, Scopus, and the Cochrane Library databases were systematically reviewed. All surgical procedures including gynecologic surgery with hospital surgical volume information were eligible for analysis. Twenty-three studies met the inclusion criteria, and nine gastro-intestinal studies, seven genitourinary studies, four gynecological studies, two hepatobiliary studies, and one thoracic study were reviewed. Of those, 11 showed a positive volume–outcome association for perioperative outcomes. A study on MIS for ovarian cancer reported lower surgical morbidity in high-volume centers. Two studies were on endometrial cancer, of which one showed lower treatment costs in high-volume centers and the other showed no association with perioperative morbidity. Another study examined robotic-assisted radical hysterectomy for cervical cancer and found no volume–outcome association for surgical morbidity. There were no gynecologic studies examining the association between hospital surgical volume and oncologic outcomes in MIS. The volume–outcome association for oncologic outcome in gynecologic MIS is understudied. This lack of evidence calls for further studies to address this knowledge gap.

Association of Teaching Status and Mortality After Cancer Surgery

OBJECTIVE

To examine patient outcomes for nine cancer-specific procedures performed in teaching versus non-teaching hospitals.

SUMMARY BACKGROUND DATA

Few contemporary studies have evaluated patient outcomes in teaching versus non-teaching hospitals across a comprehensive set of cancer-specific procedures.

METHODS

Use of national Medicare data to compare 30-, 60-, and 90-day mortality rates in teaching and non-teaching hospitals for cancer-specific procedures. Risk-adjusted 30-day, all-cause, postoperative mortality overall and for each specific surgery, as well as overall 60- and 90-day mortality rates, were assessed.

RESULTS

The sample consisted of 159,421 total cancer surgeries at 3,151 hospitals. Overall thirty-day mortality rates, adjusted for procedure type, state, and invasiveness of procedure were 1.3% lower at major teaching hospitals (95%CI=-1.6% to -1.1%; p<0.001) relative to non-teaching hospitals. After accounting for patient characteristics, major teaching hospitals continued to demonstrate lower mortality rates compared with non-teaching hospitals (-1.0% difference [95%CI -1.2% to -0.7%]; p<0.001). Further adjustment for surgical volume as a mediator reduced the difference to -0.7% (95%CI -0.9% to -0.4%, p<0.001). Cancer surgeries for four of the nine disease sites (bladder, lung, colorectal and ovarian) followed this overall trend. Sixty- and ninety-day overall mortality rates, adjusted for procedure type, state, and invasiveness of procedure showed that major teaching hospitals had a 1.7% (95%CI -2.1% to -1.4%; p<0.001) and 2.0% (95%CI -2.4 to -1.6%, p<0.001) lower mortality relative to non-teaching hospitals. These trends persisted after adjusting for patient characteristics.

CONCLUSIONS

Among cancer-specific procedures for Medicare beneficiaries, major teaching hospital status was associated with lower 30-, 60-, and 90-day mortality rates overall and across four of the nine cancer types.

The Role of Minimally Invasive Surgery in the Care of Women with Ovarian Cancer: A Systematic Review and Meta-analysis

OBJECTIVE

To synthesize evidence from studies investigating survival outcomes for patients with ovarian cancer undergoing minimally invasive surgery (traditional or robotic laparoscopy) compared with those for patients with ovarian cancer undergoing laparotomy.

DATA SOURCES

We searched Ovid MEDLINE and Embase (from inception to December 2019).

METHODS OF STUDY SELECTION

Observational cohort studies and randomized controlled trials that compared risk of recurrence or death between women undergoing minimally invasive and open procedures for staging (10), interval cytoreduction (4), secondary cytoreduction (2), and evaluation of resectability (1) were included.

TABULATION, INTEGRATION, AND RESULTS

Data on the number of participants, number of deaths and recurrences, and results of analyses of overall or progression-free survival were abstracted for all studies. A random-effects meta-analysis was used to pool the results of studies comparing minimally invasive staging and open staging. The surgical approach (minimally invasive versus open) was not significantly associated with hazard of death or recurrence (pooled hazard ratio 0.92; 95% confidence interval, 0.61-1.38) or all-cause mortality (pooled hazard ratio 0.96; 95% confidence interval, 0.49-1.89). One randomized trial demonstrated that diagnostic laparoscopy could triage patients to neoadjuvant chemotherapy and avoid suboptimal primary surgery, without affecting recurrence-free or overall survival. Most studies included in this review were observational and at high risk for bias, and few studies accounted for potential confounding.

CONCLUSION

Although existing studies do not demonstrate deleterious survival effects associated with minimally invasive surgery for ovarian cancer, these data must be viewed with caution given the significant methodologic shortcomings in the existing literature.

Minimally invasive radical hysterectomy for early-stage cervical cancer: Volume-outcome relationship in the early experience period

OBJECTIVE

Minimally invasive radical hysterectomy (MIS-RH) for early-stage cervical cancer is a relatively new surgical procedure with increased utilization in the mid-/late-2000s. This study examined the association between hospital surgical volume for MIS-RH and perioperative outcomes for early-stage cervical cancer in the period of early adoption.

METHODS

This population-based retrospective study queried the National Inpatient Sample from 2007 to 2011. Cervical cancer cases treated with MIS-RH were examined (n = 2202 from 163 hospitals). Annualized hospital surgical volume was defined as the average number of procedures performed per year in which at least one case was performed. Characteristics and outcomes related to MIS-RH use were assessed. The comparator cohort included RH by laparotomy (Open-RH; n = 11,187 from 405 hospitals).

RESULTS

Among MIS-RH-offering centers, 42.3% had average 1 case/year and surgical volume of >4 cases/year represented the top decile. When stratified by MIS-RH types, on average 31.3 centers performed robotic-assisted approach per year versus 11.5 centers for the traditional approach. Small bed capacity centers were most likely to perform robotic-assisted RH (adjusted-odds ratio 4.07, P < 0.001). In the traditional MIS-RH group, higher hospital surgical volume was associated with lower surgical morbidity (P = 0.025) whereas in the robotic-assisted approach higher hospital surgical volume was associated with higher surgical morbidity (P < 0.001). In the Open-RH cohort, higher hospital surgical volume was significantly associated with decreased surgical morbidity and mortality (both, P < 0.001).

CONCLUSION

In the mid-/late-2000s, MIS-RH surgical volume was modest in the United States. Small bed capacity centers adopted robotic-assisted MIS-RH more frequently, and there was a statistically significant association of increased perioperative complications among higher volume centers. In contrast, higher surgical volume was associated with improved perioperative outcomes with the traditional MIS-RH and open-RH approaches.