Anna V. Tinker

Treatment and outcomes in undifferentiated and dedifferentiated endometrial carcinoma

Undifferentiated and dedifferentiated endometrial carcinoma is a rare type of uterine malignancy. This study assesses disease characteristics, treatment and survival outcomes in patients with undifferentiated and dedifferentiated endometrial carcinoma treated at BC Cancer. All patients diagnosed with undifferentiated and dedifferentiated endometrial carcinoma between 2000 and 2019 at BC Cancer were reviewed centrally. Clinical, pathologic, treatment and outcomes were reviewed retrospectively. The Kaplan-Meier method was used to evaluate overall survival (OS) and disease-free survival (DFS). Multivariable analysis was performed using Cox regression analysis. Fifty-two patients were included, 33% had undifferentiated carcinoma and 67% dedifferentiated carcinoma. Sixty-nine percent of those who had mismatch repair (MMR) testing of their tumor had an abnormal profile. The 5-year DFS was 80% (95% confidence interval [CI]=71%-89%) for stage I/II, 29% (95% CI=28%-40%) for stage III and 10% (95% CI 1%-19%) for stage IV. The 5-year OS was 84% (95% CI=75%-92%) for stage I/II, 38% (95% CI=26%-50%) for stage III and 12% (95% CI=1%-24%) for stage IV. Multivariate analysis showed that receiving adjuvant chemotherapy, adjuvant radiotherapy, lower stage and better Eastern Cooperative Group performance status were associated with improved DFS (p<0.05). Patients with stage I/II undifferentiated and dedifferentiated endometrial carcinoma had excellent survival outcomes, those with stage III/IV had worse outcomes, similar to previously reported. Adjuvant chemotherapy and radiotherapy were associated with improved DFS. MMR testing should be performed for these patients due to the high incidence of abnormal profiles.

FOLR1 as a therapeutic target in platinum-resistant ovarian carcinoma: unique expression patterns across ovarian carcinoma histotypes and molecular subtypes of low-grade serous carcinoma

With the development of novel antibody-drug conjugates (ADCs), folate receptor alpha (FOLR1) is a promising therapeutic target for the treatment of platinum-resistant tubo-ovarian carcinomas. The main aims of this study were to assess FOLR1 protein expression in a large cohort of ovarian carcinoma histotypes. To inform future clinical trial design we identified molecular correlates of FOLR1 expression in low-grade serous carcinoma (LGSC). One thousand five hundred forty-seven ovarian carcinoma samples from 5 different Canadian cohorts were successfully evaluated by immunohistochemistry for FOLR1 expression using the PS2+ system. Statistical analyses with clinicopathological parameters, LGSC molecular subtypes, and overall survival (OS) were performed. High FOLR1 expression was detected in 44% of high-grade serous carcinomas, and in 30% LGSC, 8% clear cell, 6% endometrioid, and 0% mucinous and/or mesonephric-type adenocarcinomas. In 160 LGSC cases, FOLR1 expression was more frequent in cases with normal MAPK pathway status (37% MAPK wild type vs. 14% canonical MAPK pathway mutations; p=0.002), low progesterone receptor (PR) expression (41%) vs. 23% (Allred score >2; p A significant proportion of LGSC express high FOLR1 levels supporting the development of clinical trials to investigate ADCs targeting FOLR1 as novel agents for treating this disease. In LGSC, high FOLR1 expression was associated with fewer MAPK pathway alterations, low PR expression, and p16 loss.

Low-grade serous carcinoma (LGSC): A Canadian multicenter review of practice patterns and patient outcomes

Patients with advanced low-grade serous carcinoma (LGSC) have poor long-term survival rates. As a rare histotype, there are uncertainties regarding the use of current therapies. Thus, we studied practice patterns and treatment outcomes as part of a national initiative to better understand and improve the care of women with advanced LGSC. This retrospective cohort study was conducted in 5 Canadian referral institutions from 2000 to 2016. Data collection and pathology reporting were standardized. Outcome measures included overall survival (OS), progression-free survival (PFS), progression-free intervals (PFI), and time to next treatment (TTNT). Cox regression analysis was used to evaluate the effects of clinical and pathologic factors on outcomes and prognosis. There were 134 patients (stage II-IV) with a median follow-up of 32.4 months (range 1.6-228). Four primary treatments were compared across institutions: 1) surgery followed by chemotherapy (56%), 2) neoadjuvant chemotherapy (NACT) followed by surgery (27%), 3) surgery alone (9%), and 4) surgery followed by anti-hormone therapy (4%). Primary platinum/paclitaxel chemotherapy was used in 81%. Patients treated with NACT had worse PFS. Multivariable Cox regression analysis identified lesser residual disease, younger age, and primary peritoneal origin as variables significantly associated with better OS/PFS (p < 0.03). One institution had significantly better PFS than the others (p = 0.025), but this finding could be related to a higher frequency of primary peritoneal LGSC. PFI and TTNT intervals in patients with relapsed disease were not significantly different after the first relapse irrespective of treatment type. There are notable differences in practice patterns across Canada. This underscores the need for ongoing strategies to measure, evaluate and achieve optimal patient outcomes for women with advanced LGSC.

Germline Testing and Somatic Tumor Testing forBRCA1/2Pathogenic Variants in Ovarian Cancer: What Is the Optimal Sequence of Testing?

PURPOSEIn 2020, ASCO recommended that all women with epithelial ovarian cancer have germline testing for BRCA1/2 mutations, and those without a germline pathogenic variant (PV) should have somatic tumor testing to determine eligibility for a poly (ADP-ribose) polymerase inhibitor. Consequently, the majority of patients with ovarian cancer will have both germline testing and somatic testing. An alternate strategy is tumor testing first and then germline testing if there is a PV in the tumor and/or significant family history. The objective was to conduct a cost-effectiveness analysis comparing the two testing strategies.METHODSThe Markov model compared the costs (US dollars) and benefits of two testing strategies for newly diagnosed ovarian cancer: (1) ASCO strategy and (2) tumor testing triage for germline testing. Data were applied from SOLO-1, and costs were from wholesale acquisition prices, Medicare, and published sources. Sensitivity analyses accounted for uncertainty around various parameters. Monte Carlo simulation estimated the number tested and identified with germline and somatic BRCA PV for olaparib maintenance treatment annually in the US population.RESULTSThe ASCO strategy was more effective but more costly than tumor testing triage in identifying patients for olaparib, with an incremental cost-effectiveness ratio of $281,296 US dollars per progression-free life year gained. Assuming 10,000 eligible patients with ovarian cancer annually, Monte Carlo simulation yielded comparable numbers of patients with BRCA PV in the germline and tumor with the ASCO and tumor testing triage strategies (2,080 v 2,062, respectively), but substantially higher number of patients tested using the ASCO strategy (8,052 v 3,076).CONCLUSIONThe ASCO strategy may identify more BRCA PVs but is not cost-effective. Tumor testing in epithelial ovarian cancer as triage for germline testing is the favored strategy in this health care system.

Identifying high-risk relapse in early-stage I to II ovarian cancer using the CA125 ELIMination rate constant K (KELIM) score: a Gynecologic Cancer InterGroup individual patient-data meta-analysis

Despite curative surgery and adjuvant chemotherapy, a significant number of early stage I to II ovarian cancers relapse. The CA125 ELIMination rate constant K (KELIM) is a pragmatic indicator of tumor intrinsic chemosensitivity in advanced epithelial ovarian cancer. We assessed the prognostic value of KELIM in patients with early-stage ovarian cancer, with respect to 5-year recurrence-free survival and overall survival, using the Meta-Analysis in Ovarian Cancer, which is the Gynecologic Cancer InterGroup individual patient-data meta-analysis of randomized trials evaluating different adjuvant chemotherapy regimens. Individual patient KELIM values were previously estimated in 5884 patients from the Meta-Analysis in Ovarian Cancer. The prognostic value of KELIM was assessed using univariable & multivariable analyses in patients with resected International Federation of Gynecology and Obstetrics stage I and II disease. Overall, 1143 patients were identified, including clear cell (46.7%); serous (23.7%); endometrioid (12.4%); and mucinous carcinomas (3.9%). In multivariable analyses, a favorable KELIM score (≥1.0) was associated with higher 5-year recurrence-free survival (68.3% vs 55.9%; HR 0.61, 95% CI 0.48 to 0.77) and 5-year overall survival (80.7% vs 72.8%; HR 0.50, 95% CI 0.36 to 0.68), as was the histological sub-type. In exploratory analyses, KELIM score was a prognostic factor regarding 5-year recurrence-free survival and overall survival across all sub-types (especially clear cell carcinoma and serous, with HR ranging from 0.45 to 0.63) with baseline CA125 ≥15 IU/L, except for mucinous histology. The pragmatic KELIM score is an independent prognostic factor in patients with a non-mucinous stage I to II ovarian cancer optimally resected and treated with adjuvant chemotherapy. KELIM may help identify the patients at higher risk of relapse and death requiring closer follow-up or treatment intensification.

Bridging historical evidence and contemporary strategies in the adjuvant treatment of early-stage epithelial ovarian cancer

The umbrella term "epithelial ovarian cancer" encompasses 5 histologic sub-types with distinct molecular profiles and varying sensitivities to chemotherapy. Historical trials investigating adjuvant management of early-stage disease have not accounted for this heterogeneity. This review examines the evidence guiding the management of stage I and II epithelial ovarian cancer according to histologic sub-type and discusses its application in contemporary modern setting. Areas of interest for future research are highlighted, with an emphasis on the need for more personalized adjuvant therapy using predictive biomarkers and targeted treatments.