Women with advanced/recurrent endometrial cancer, especially those with the non-endometrioid (type II) subtype, experience poor survival outcomes, according to a real-world study published in Gynecologic Oncology.

Investigators aimed to describe real-world patient attributes, treatment patterns, and outcomes according to histological subtype among women (N=2,202) with advanced endometrial cancer using a nationwide EHR database. Patients were diagnosed between January 1, 2013 and September 30, 2020, and follow-up was conducted from start of systemic treatment until March 30, 2021, last available follow-up visit, or death, whichever occurred first. Outcomes according to histological subtype included Kaplan–Meier estimates of overall survival (OS) and time to first subsequent therapy or death (TFST).

More than one-half of patients (59.8%; N=1,317) had endometrioid carcinoma and one-quarter (25.0%; N=551) had uterine serous carcinoma. Other subtypes included endometrial cancer not otherwise specified (9.6%; N=212), clear cell carcinoma (4.2%; N=92), and uterine carcinosarcoma (1.4%; N=30). Most patients received treatment in a community setting (82.7%; N=1,822) and presented with stage III/IV disease (74.0%, including 1,073 with stage III and 557 with stage IV) at initial diagnosis.

Patients with endometrioid carcinoma were slightly younger than those with uterine serous carcinoma or other endometrial cancers (median age, 64.0 vs 69.0 and 66.5 years, respectively). Compared with other subtypes, more women with uterine serous carcinoma were Black (26.3%). Patients were primarily overweight or obese (median BMI, 32.1 kg/m2), according to the researchers, a finding that was consistent across all subtypes.

Regarding treatment, 33 patients did not receive systemic therapy and 21 died during follow-up (median survival, 2.6 months; range, 0.9-36.4 months). Additionally, 12 patients were censored at the end of follow-up, with a median follow-up of 7.4 months (range, 0.0-67.4 months). Compared with patients continuing to treatment, untreated patients were more often Black (30.3% vs 14.2%) or had stage I/II disease (72.7% vs 20.7%).

First-line systemic treatments included platinum-based combination chemotherapy (N=1,779/2,169; 82.0%), platinum-based single-agent chemotherapy (N=172/2,169; 7.9%), and platinum-based chemotherapy plus HER-2 therapy (N=62/2,169; 2.9%). The study team noted comparable patterns across histological subtypes. Among patients who received platinum-based combination therapy (N=1,179), 68.0% had a taxane. Overall median duration of first-line treatment was 9.2 months.

In total, 1,001 patients were treated with second-line systemic therapy, the most common of which was platinum-based combination chemotherapy (27.8%; N=278). Other treatments included endocrine-based therapy (N=170) and pegylated liposomal doxorubicin single-agent therapy (N=110). PD-1/PD-L1 monotherapy was used as a second-line treatment in 50 patients and in combination with VEGF inhibitors in 37 patients. Overall median length of second-line treatment was 5.9 months.

Among 2,169 patients treated with systemic therapy, median OS from start of first systemic treatment after diagnosis was shorter in patients with uterine serous carcinoma (31.3 months) and other endometrial cancers (29.4 months) than in patients with endometrioid carcinoma (70.8 months). Median TFST from start of first systemic treatment was also shorter for patients with uterine serous carcinoma (10.6 months) and other endometrial cancers (9.0 months) than patients in the endometrioid subgroup (18.9 months). Outcomes were consistently poorer for Black women compared with White women regarding both median OS and TFST from start of first systemic treatment.

The researchers noted that the study is the most comprehensive examination of current treatment for advanced/recurrent endometrial cancer in the community setting to date. The poor prognosis observed for advanced/recurrent endometrial cancer aligns with existing literature, they continued, and underscores the urgent need for more effective therapies.