Serous borderline tumor of the ovary with isolated cardiophrenic lymph node spread at diagnosis

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Serous borderline tumor outside of the peritoneal cavity is rare.

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Involvement of cardiophrenic lymph nodes with serous borderline tumor can occur.

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Preoperative imaging may aid surgical planning even in serous borderline tumor cases.

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Sequencing can help confirm a diagnosis of serous borderline tumor at distant sites.

The incidence of myelodysplastic syndrome in patients receiving poly-ADP ribose polymerase inhibitors for treatment of solid tumors: A meta-analysis

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Background: Clinical trials have reported improved outcomes with PARPi (poly [adenosine diphosphate–ribose]-ADP polymerase inhibitor) therapy in ovarian, breast, pancreatic and lung cancers. There is concern that PARPi therapy may cause myelodysplastic syndrome (MDS). In this meta-analysis we seek to quantify the risk of MDS among patients treated with PARPi for solid tumor malignancies. Methods: We searched Medline, Embase, and Cochrane databases (up to January 6, 2020) to abstract randomized controlled trials that include a PARPi in the experimental arm in solid tumors. Combinations included PARPi versus (vs.) placebo, PARPi vs. cytotoxic treatment, and PARPi with cytotoxic treatment vs. cytotoxic treatment. We used to time-to-event curves to estimate person-time and calculated the incidence of MDS among all studies. We used random-effects Poisson regression models to estimate pooled incidence risk ratio (RR) for developing MDS. Results: We identified 14 studies, 10 in ovarian, 3 in breast, and 1 in pancreatic cancer patients. Of 5,646 patients, 62.3% received a PARPi alone or in combination with chemotherapy or bevacizumab, and 37.8% received treatment consisting of placebo alone or with chemotherapy or bevacizumab. PARPi were investigated as an upfront treatment in 2,827 patients, and as treatment for recurrence in 2,819 patients. The incidence of MDS was 6.73 cases vs. 3.85 per 1000 person-years in patients receiving PARPi as compared to control corresponding to a 3-year cumulative incidence of 2.0% and 1.1%. Accounting for intra-study clustering, PARPi use was associated with a 60% increase in risk (incidence RR 1.60, 95% Confidence Interval [CI] 0.89-2.87) of MDS compared to control. In the upfront setting, patients randomized to PARPi were twice as likely to develop MDS (RR 2.08, 95%, CI 1.39-3.64). Among patients treated for recurrence, the risk of MDS appeared to be similar among patient randomized to PARPi or control treatment (RR 1.13, 95% CI 0.35-3.64). In studies that compared PARPi in combination with other cytotoxic treatment vs. cytotoxic treatment alone, PARPi was associated with a large risk of MDS (RR 5.08, 95% CI 1.36-19.03). Conclusions: In pooled estimates from randomized controlled trials in solid tumors PARPi treatment appears to be associated with an increased incidence of MDS particularly in the upfront setting and when combined with cytotoxic treatment. Despite pooling 14 randomized trials our estimates remain imprecise due to the rarity of MDS.

Multivariable analysis of association of beta-blocker use and survival in advanced ovarian cancer

OBJECTIVE

In this study, we sought to evaluate the relationship between survival and beta blocker use in both the primary and interval debulking setting while adjusting for frequently co-administered medications.

METHODS

We performed a retrospective cohort study reviewing charts of women who underwent primary or interval cytoreduction for stage IIIC and IV epithelial ovarian cancer. The exposure of interest was beta-blocker use identified at the time of cytoreduction. The outcomes of interest were PFS and OS. We collected demographic/prognostic variables and information about use of aspirin, metformin, and statins. We used the Kaplan-Meier method and Cox proportional hazards models in survival analyses.

RESULTS

534 women who underwent surgery for stage IIIC or IV ovarian cancer were included in the study. The median age at diagnosis was 64 and 84.8% of women had serous carcinoma. We identified 105 women (19.7%) on a beta-blocker of whom 94 (90%) were on a cardioselective beta-blocker. Additionally, 24 women (4.5%) were on metformin, 91 (17%) on aspirin, and 128 (24%) on a statin. In univariable analysis, beta-blocker users had a median overall survival of 29 months vs 35 months among non-users (hazard ratio HR = 1.52, p = 0.007). After adjustment for important demographic, clinical, and histopathologic factors, as well as use of other common medications, beta-blocker use remain associated with an increased hazard of death (adjusted HR 1.57, p = 0.006).

CONCLUSION

In this retrospective study, we found that patients identified as being on a beta-blocker at the time of surgery had worse overall survival and greater risk of death when compared to those patients not on betablockers. Importantly, 90% of patients on beta-blockers were identified as being on a cardioselective beta-blocker.

Clinical characteristics and outcomes after bowel surgery and ostomy formation at the time of debulking surgery for advanced-stage epithelial ovarian carcinoma

OBJECTIVE

There are limited data on clinical outcomes of patients with advanced-stage epithelial ovarian cancer who require ostomy formation at the time of either primary cytoreductive surgery or interval cytoreductive surgery. The objective of this study was to evaluate patients undergoing bowel surgery and ostomy formation after primary or interval surgery.

METHODS

Patients with International Federation of Gynecology and Obstetrics (FIGO) stage IIIC-IV epithelial ovarian cancer who underwent cytoreductive surgery between January 2010 and December 2014 were identified retrospectively. Patients with non-epithelial histology, low-grade serous histology or incomplete medical records were excluded. Demographic and clinical data were collected and analyzed. Age, stage, co-morbidity index, pre-operative CA125, pre-operative albumin, and Aletti surgical complexity score were included in a multivariable logistic regression model to assess independent associations with ostomy formation.

RESULTS

A total of 554 patients were included in the study. Of these, 261 (47%) underwent primary cytoreduction and 293 (53%) underwent interval cytoreduction. Patients undergoing primary surgery were more likely to undergo bowel resection, compared with interval surgery patients (37.2% vs 14%, p<0.001). Of the 139 (25.1%) patients who underwent bowel surgery, 25 (18%) underwent ostomy formation (11 ileostomies and 14 colostomies). Rates of ostomy formation were similar between the groups (6.1% primary vs 3.1% interval, p=0.10). Patients undergoing ostomy formation were more likely to have longer mean operative time (335 vs 229 min, p<0.001) and undergo small and large bowel resections at the time of cytoreductive surgery (44% vs 14%, p<0.001). Multivariate analysis revealed that a high surgical complexity score was associated with ostomy formation. Of the patients who underwent ostomy formation, 13 (43.3%) underwent stoma reversal including 11 ileostomies and two colostomies. Median time to ostomy reversal was 7 months.

CONCLUSION

Bowel surgery is more common among patients undergoing primary surgery as compared with interval surgery, but this does not result in an increased risk of ostomy formation.

Phase 2, two-group, two-stage study of avelumab in patients (pts) with microsatellite stable (MSS), microsatellite instable (MSI), and polymerase epsilon (POLE) mutated recurrent/persistent endometrial cancer (EC)

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Background: This non-randomized phase 2 study evaluated the PD-L1 inhibitor avelumab in two cohorts of EC: i) MSI/ POLE cohort including ECs with immunohistochemical (IHC) loss of expression of at least one of the mismatch repair (MMR) proteins and/or documented mutation in the exonuclease domain of POLE and ii) MSS cohort including ECs with normal IHC expression of all MMR proteins. Methods: Eligibility criteria included measurable disease, unlimited prior therapies, and any EC histology. Co-primary endpoints were confirmed objective response (OR) and progression-free survival rate at 6 months (PFS6). Avelumab 10 mg/kg IV was given every 2 weeks until progression or unacceptable toxicity. In the 1st stage, 16 pts were enrolled in each cohort; if there were ≥2 ORs or ≥2 PFS6 responses, accrual would continue to the 2nd stage with enrollment of 19 additional pts. Overall, if there are ≥4 ORs or ≥8 PFS6 responses, avelumab would be considered worthy of further study in each cohort. Results: As of 12/2018, 33 pts were enrolled. The MSS cohort was closed at the 1st stage due to futility; of 16 pts in the MSS cohort, only 1 pt exhibited an OR and PFS6 response [ORR and PFS6 rate 6.25% (95% CI 0.16%-30.2%)]. Conversely, the MSI/POLE cohort reached the primary endpoint of 4 ORs after accrual of only 17 pts. Two pts in the MSI/POLE cohort did not initiate protocol therapy and were excluded from all analyses. Of 15 pts in the MSI/POLE cohort, 4 pts exhibited OR [1CR+3PRs, OR rate (ORR) 26.7% (95% CI 7.8%-55.1%)] and 6 pts (including the 4 pts with OR) exhibited PFS6 responses [PFS6 rate 40.0% (95% CI 16.3%-66.7%)], 4 ongoing and 3 approaching 2 yrs. Twenty-two pts (71%) reported treatment related toxicities, 6 patients (19%) G3 toxicities; there were no treatment-related G4 and G5 toxicities. In the MSI/POLE cohort, 5 of 6 PFS6 responses were observed in pts with ≥3 lines of prior therapy (p = 0.011) and in tumors who were PD-L1 negative by IHC. Further correlative work will be reported at the meeting. Conclusions: In EC pts stratified by MSI/POLE status, MSI vs MSS status appears to be correlated with avelumab response even in PD-L1 negative tumors. Responses in the MSI/POLE cohort were more frequent in more heavily pretreated patients, a finding that warrants further investigation. Clinical trial information: NCT02912572.

Effect of adoption of neoadjuvant chemotherapy for advanced ovarian cancer on all-cause mortality

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Background: Use of neoadjuvant chemotherapy followed by surgery for advanced epithelial ovarian cancer is controversial in the United States. Methods: Use of neoadjuvant chemotherapy for stage IIIC and IV ovarian cancer has increased gradually in the United States since 2007, but rates of adoption vary by region. Between 2011 and 2012, use of neoadjuvant chemotherapy increased by 27% in the New England and East South Central regions, but remained unchanged in three control regions (South Atlantic, West North Central, and East North Central regions). Employing prospectively collected data from Commission on Cancer-accredited cancer programs in the United States, we used this discontinuity in treatment approach to assess the causal impact of neoadjuvant chemotherapy on all-cause mortality in a quasi-experimental fuzzy regression discontinuity design. Kaplan-Meier curves and proportional hazard models were estimated to compare mortality differences between rapidly-adopting regions and controls. We also conducted a cross-sectional analysis of the relationship between regional use of neoadjuvant chemotherapy and survival. Results: We identified 1,156 women treated for advanced epithelial ovarian cancer during 2011 and 2012 in the two rapidly-adopting regions and 4,878 women in the three control regions. In the rapidly-adopting regions, patients treated in 2012 compared with 2011 had a mortality hazard ratio (HR) of 0.81 (95%CI=0.71-0.94) after adjusting for mortality time trends, while no difference was observed in control regions (HR=1.02, 95%CI=0.93-1.12). Compared with control regions, we observed larger declines in 90-day surgical mortality (7.0% to 4.0% versus 5.0 to 4.3%, p=0.01) and in the proportion of women not receiving surgery and chemotherapy (20.0% to 17.4% versus 19.0 to 19.5%, p=0.04) in rapidly adopting regions. Cross-sectional analysis confirmed that treatment in regions with greater use of neoadjuvant chemotherapy was associated was lower mortality (p=0.001). Conclusions: Adoption of neoadjuvant chemotherapy for advanced epithelial ovarian cancer in New England and East South Central regions led to a sizable reduction in mortality within three years after diagnosis.