The Role of Hereditary Thrombophilia Testing in Management of First-Time Pulmonary Embolism

AIM

Hereditary thrombophilia (HT) testing is frequently conducted during the evaluation of patients with pulmonary embolism (PE). However, the utility of routine HT testing in this setting is unclear. We sought to assess the association of HT with risk of recurrent venous thromboembolism (VTE) following first-time PE.

METHODS

We conducted a multi-hospital retrospective study. Two hundred and ninety (290) patients with a first-time PE, who had been tested for HT, completed at least 3 months of therapeutic anticoagulation (AC), subsequently discontinued AC, and were followed for at least 36 months thereafter, were included.

RESULTS

HT was present in 48 of the 290 included patients (17%). Median follow-up after discontinuing AC was 61 months (interquartile range, 43-79 months). The overall recurrence rate of VTE during follow-up was 58 per 290 (20%). A total of 47 of 242 patients (19%) in the HT-absent group had a recurrent VTE, compared with 11 of 48 (22%) in the HT-present group. There was no significant difference in VTE-free survival between groups on Kaplan-Meier analysis; the hazard ratio (HR) for VTE recurrence for those with HT compared to those without (HR HT-present: HT-absent) was 1.240 (95% confidence interval [CI] 0.614-2.502; p=0.548). On multivariable analysis, HT was not associated with risk of recurrent VTE (HR 1.262; 95% CI 0.640-2.488), and the only variable associated with VTE recurrence was unprovoked PE (HR 2.954; 95% CI 1.64-5.314).

CONCLUSIONS

These findings demonstrate that the presence of HT is not associated with the risk of recurrent VTE following first PE, and support limiting the use of HT testing among patients with first PE.

Abstract P1-04-09: Correlating Predicted Adjuvant Therapy Benefit and Risk of Recurrence between Breast Cancer Index (BCI) and 21-gene Oncotype DX Recurrence Score (RS)

Background: The 21-gene Recurrence Score (Oncotype DX) is a genomic assay that provides prognostic information for distant recurrence risk and is predictive of adjuvant chemotherapy benefit in hormone receptor (HR)-positive, HER-2 negative early-stage breast cancer (EBC). The Breast Cancer Index (BCI) is another molecular gene expression-based assay that evaluates the utility of extending adjuvant endocrine therapy (ET) from 5 to 10 years and predicts risk of distant recurrence. In January 2021, the National Comprehensive Cancer Network (NCCN) Guidelines added BCI to guide duration of adjuvant ET as a category 2A recommendation. The goal of this study was to evaluate the association between BCI and RS in terms of their predicted benefit for adjuvant therapy and risk of distant recurrence. We also assessed the association of various anatomic and biologic tumor features with BCI. Methods: We performed a retrospective chart review of all patients with HR-positive EBC who had a BCI and Oncotype DX performed between 2007-2021. Demographics, tumor characteristics and BCI and RS results were extracted from the electronic medical record. Patients were categorized by BCI predictive of extended ET (formerly BCI high) versus not (formerly BCI low) and RS of low (0-10), intermediate (11-25) and high (26-100). Numerical values for distant recurrence risk were recorded for both BCI and Oncotype DX tests. Multivariable regression models were used to assess the relationship between BCI and Oncotype DX as well as factors associated with each. Results: We identified 153 women with HR-positive EBC with both RS and BCI performed. The median age of the population was 57 years and 25% were premenopausal. 32% (n=49) had a BCI result predictive of benefit from extended adjuvant ET. When comparing patients with BCI predictive of extended ET versus those with BCI not predictive of extended ET, there was no association between BCI and RS based on multivariate logistic regression models, p=0.7. A similar distribution of RS was observed between patients who had a BCI result predictive of benefit from extended ET versus not predictive. Among 49 patients with a BCI predictive of extended ET, 35% had high RS, 63% intermediate RS and 2% low RS. Among 104 patients with a BCI not predictive of extended ET, 24%, 73% and 3% had high, intermediate, and low RS, respectively. Multivariate regression models revealed an association between poorly differentiated tumors and BCI result predictive of extended ET, p=0.002. No associations were observed between BCI and menopausal status, ER%, PR%, tumor size or lymph node positivity. Regarding risk of recurrence, there was an association between BCI and Oncotype DX in terms of their predicted numerical risk of recurrence, p< 0.001. Higher percentage of PR positivity, poorly differentiated tumors, and lymph node positivity were associated with a higher risk of recurrence on the BCI. Conclusions: In our patient population selected to have Oncotype DX and BCI performed, we found no association between the two genomic assays in terms of their predictive benefit. However, there was an association between Oncotype DX and BCI in terms of their prognostic ability. Given the increased use of BCI since its inclusion in national guidelines, it is important to understand its relationship with other genomic assays especially when used to guide clinical decisions and estimate prognosis.

Citation Format: Rima Patel, Nicole Casasanta, Zhiqiang Li, Melanie Kier, Julia Blanter, Sophie Sohval, Malin Hovstadius, Catherine Wu, Marc Fink, Xiang Zhou, Brittney Zimmerman, Krystal Cascetta, Rong Chen, William Oh, Amy Tiersten. Correlating Predicted Adjuvant Therapy Benefit and Risk of Recurrence between Breast Cancer Index (BCI) and 21-gene Oncotype DX Recurrence Score (RS) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-04-09.

The utility of PD-L1 as a prognostic marker in pancreatic ductal adenocarcinoma (PDAC)

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Background: The PDAC tumor microenvironment is notoriously immune suppressive, and PD-L1 expression is one mechanism by which tumor cells evade immune surveillance. In PDAC, clinical trials evaluating immunotherapy have not been successful in microsatellite stable tumors, and PD-L1 has not been shown to be predictive of immunotherapy response. Studies suggest that high PD-L1 expression may be associated with worse clinical outcomes and more advanced disease. We aimed to evaluate PD-L1 as a prognostic marker in routine clinical practice using a real-world population of patients with PDAC. Methods: We conducted a retrospective study of patients with PDAC at Mount Sinai Health System from 5/2017 to 12/2021 for whom PD-L1 status by immunohistochemistry (22c3) and combined positive score (CPS) were reported. We assessed the association between PD-L1 expression and overall survival (OS) using Kaplan-Meier estimates and multivariable Cox proportional hazards regression models. Chi-squared tests were used to evaluate the association between PD-L1 expression and mutations detected by routine next generation sequencing (NGS) using a standard panel. Results: 107 patients were evaluable. At diagnosis, median age was 68 years, 43% of patients were male, 83% had ECOG performance status 0-1, 38% had resectable disease, 14% had borderline resectable disease, and 48% had unresectable disease. Ultimately, 45 patients (42%) underwent surgery. 44% patients had gemcitabine-based initial therapy, perioperatively or as first-line, and 56% had 5FU-based initial therapy. 35% of patients had radiation therapy (RT) at any time. In the entire cohort, 44 (41%) patients had PD-L1 CPS < 1, and 63 patients had CPS ≥ 1. 93 patients had NGS, but no associations were found between PD-L1 status and commonly mutated genes, such as KRAS and SMAD4. For patients who underwent surgery, the median OS (mOS) of patients with PD-L1 CPS ≥ 1 was 46.1 months, and mOS of PD-L1 CPS < 1 was 29.8 months ( P = 0.13). For patients who did not receive surgery, mOS was 12.3 months for CPS ≥ 1 and 15.8 months for CPS < 1 ( P = 0.07). When adjusted for age, gender, ECOG score, stage, type of chemotherapy, RT, and baseline CA 19-9 level, patients who received surgery and had a CPS ≥ 1 had better OS than those who had CPS < 1 (HR 0.22, 95% CI 0.06-0.77, P = 0.02). For patients without resection, CPS ≥ 1 was not associated with OS in the adjusted model (HR 1.52, 95% CI 0.73-3.15, P = 0.26). However, patients with PD-L1 CPS ≥ 10 without surgery had worse OS compared to patients with CPS < 1 in the adjusted model (HR 11.02, 95% CI 2.89-41.96, P < 0.001). Chemotherapy type and receipt of RT did not modify OS based on PD-L1 expression. Conclusions: In resected PDAC, PD-L1 CPS ≥ 1 was independently associated with improved OS, whereas in unresectable PDAC, PD-L1 CPS ≥ 10 was independently prognostic of worse OS. PD-L1 expression is a potential prognostic factor in PDAC and may be a useful and context-dependent biomarker.