Targeted therapy in the treatment of uterine serous carcinoma

A clinical case of successful treatment of a giant serous endometrial carcinoma imitating ovarian cancer

Background: Giant tumors of the abdominal cavity, as a rule, occur in elderly patients with characteristic features and represent a serious problem in terms of choosing a radical method of therapy. Of particular difficulty are cases of giant serous endometrial cancer, requiring a differential diagnosis with ovarian cancer. Clinical case description: A clinical case of giant serous endometrial cancer mimicking ovarian cancer in a 55-year-old woman is presented. The patient came to the oncology department with complaints of abdominal enlargement, difficulty breathing and bloody discharge from the genital tract. The examination revealed the following: a giant formation (4065 cm), occupying the entire pelvic and the entire abdominal cavities, ascites, lesions of the retroperitoneal lymph nodes, and the greater omentum, an umbilical hernia. A chest CT showed multiple contrast-accumulating circular shadows of 313 mm (metastases). By the decision of the council, after the preliminary chemoembolization of both the uterine and ovarian arteries, a supravaginal amputation of the uterus with appendages was performed, along with the resection of the greater omentum, removal of the umbilical hernia with positioning a plastic mesh implant and excision of an excess skin flap. The histological examination of the intraoperative material made it possible to verify the diagnosis of a serous endometrial carcinoma with subtotal tumor necrosis, the myometrium invasion of more than a half of its thickness, with the egress to the perimetrium, metastatic lesions of both ovaries, the greater omentum, anterior abdominal wall. Stage T3b (FIGO IIIB). In the postoperative period, 6 courses of Paclitaxel / Carboplatin (AUC4-5) chemotherapy were carried out with a pronounced clinical effect. The patient was discharged in a satisfactory condition. The control PET-CT scan after the 6th chemotherapy course showed no pathology in the thoracic cavity, and no process progress in the abdominal cavity. Currently, the remission of the disease is 9 months. Conclusion: An algorithm for the diagnostic measures aimed at making the correct diagnosis is presented, and the tactics of treating a patient with giant serous endometrial cancer is described.

PD-L1 Expression in Endometrial Serous Carcinoma and Its Prognostic Significance

Purpose

Programmed death-ligand 1 (PD-L1) has been widely used as a prognostic biomarker and an immunotherapeutic target in numerous cancers, but information on the clinical significance of its expression in endometrial serous carcinoma (ESC) is largely lacking. Here, we evaluate the predictive value of PD-L1 expression in ESC.

Materials and Methods

A total of 79 cases of ESC accessioned between January 2003 and September 2015 were selected for further analysis. PD-L1 expression was evaluated in whole tissue sections of these cases by using the tumor proportion score (TPS, cut-off 1%) and combined positive score (CPS, cut-off 1) scoring methods.

Results

Overall, there was a heterogeneous expression of PD-L1, focal or patchy, in ESCs. PD-L1 positivity was observed in 43.0% of ESCs by TPS and 73.4% of ESCs by CPS. Kaplan–Meier survival analysis showed that patients with PD-L1-positive tumors suffered significantly worse OS and PFS, when compared with PD-L1 negative tumors (log-rank p = 0.037 and p = 0.003, respectively). In contrast, PD-L1 positivity by CPS within the ESC cases showed no statistical significance for OS and PFS (log-rank p = 0.720 and p = 0.928, respectively). Multivariate Cox analysis showed that PD-L1 positivity by TPS was significantly associated with PFS (HR = 1.921, p = 0.039) but not OS (HR = 1.229, p = 0.631).

Conclusion

PD-L1 expression is frequently found in ESC, suggesting a potential role of the PD-1/PD-L1 pathway as a potential therapeutic target for these tumors. PD-L1 expression by TPS also serves as a negative prognostic marker in ESC and implies an unfavorable outcome.

Comparing mutation frequencies for homologous recombination genes in uterine serous and high-grade serous ovarian carcinomas: A case for homologous recombination deficiency testing in uterine serous carcinoma

OBJECTIVE

To compare the frequencies of somatic homologous recombination (HR) gene mutations identified in next-generation sequencing (NGS) genomic profiling of uterine serous carcinomas (USCs) and high-grade serous ovarian carcinomas (HGSOCs).

METHODS

Data for this analysis was obtained from AACR Project GENIE, a multi-institutional dataset of clinical-grade NGS genomic profiling results for many cancer sites and histologic subtypes, through cBioPortal. Patient/specimen groups used for analysis were USC and HGSOC. 14 HR genes were queried for each group with respect to mutation frequency. For each HR gene, the difference in mutation frequency between the two groups was evaluated using Fisher's exact test. The threshold for statistical significance was p-value < .05.

RESULTS

In the USC group, there were 457 samples from 451 patients. In the HGSOC group, there were 1537 samples from 1515 patients. The most frequently mutated HR gene for USC was BRCA2 (4.84%) and for HGSOC was BRCA1 (9.07%). Mutation frequency was significantly different between USC and HGSOC for BRCA 1 (p < .001) and BRCA2 (p = .0379). For the 12 non-BRCA HR genes, mutation frequency was not significantly different between USC and HGSOC. The rate of patients with at least one HR gene mutation in their profiled tumor was 16.85% for USC and 25.21% of HGSOC. Most USC patients with a somatic HR mutation had only one HR gene mutated.

CONCLUSIONS

Somatic HR gene mutations were commonly identified in NGS genomic profiling of USC. Mutation frequencies for non-BRCA HR genes were not significantly different between USC and HGSOC. These data add to the growing rationale for HR deficiency tumor testing and targeting (e.g., with PARP inhibitors) in future clinical trial development for women with USC.

Pathogenesis and Clinical Management of Uterine Serous Carcinoma

Uterine serous carcinoma (USC) is an aggressive variant of endometrial cancer that has not been well characterized. It accounts for less than 10% of all endometrial cancers and 80% of endometrial cancer–related deaths. Currently, staging surgery together with chemotherapy or radiotherapy, especially vaginal cuff brachytherapy, is the main treatment strategy for USC. Whole-exome sequencing combined with preclinical and clinical studies are verifying a series of effective and clinically accessible inhibitors targeting frequently altered genes, such as HER2 and PI3K3CA, in varying USC patient populations. Some progress has also been made in the immunotherapy field. The PD-1/PD-L1 pathway has been found to be activated in many USC patients, and clinical trials of PD-1 inhibitors in USC are underway. This review updates the progress of research regarding the molecular pathogenesis and putative clinical management of USC.

Dual CCNE1/PIK3CA targeting is synergistic in CCNE1-amplified/PIK3CA-mutated uterine serous carcinomas in vitro and in vivo

Background:

Clinical options for patients harbouring advanced/recurrent uterine serous carcinoma (USC), an aggressive variant of endometrial tumour, are very limited. Next-generation sequencing (NGS) data recently demonstrated that cyclin E1 (CCNE1) gene amplification and pik3ca driver mutations are common in USC and may therefore represent ideal therapeutic targets.

Methods:

Cyclin E1 expression was evaluated by immunohistochemistry (IHC) on 95 USCs. The efficacy of the cyclin-dependent kinase 2/9 inhibitor CYC065 was assessed on multiple primary USC cell lines with or without CCNE1 amplification. Cell-cycle analyses and knockdown experiments were performed to assess CYC065 targeting specificity. Finally, the in vitro and in vivo activity of CYC065, Taselisib (a PIK3CA inhibitor) and their combinations was tested on USC xenografts derived from CCNE1-amplified/pik3ca-mutated USCs.

Results:

We found that 89.5% of the USCs expressed CCNE1. CYC065 blocked cells in the G1 phase of the cell cycle and inhibited cell growth specifically in CCNE1-overexpressing USCs. Cyclin E1 knockdown conferred increased resistance to CYC065, whereas CYC065 treatment of xenografts derived from CCNE1-amplified USCs significantly reduced tumour growth. The combination of CYC065 and Taselisib demonstrated synergistic effect in vitro and was significantly more effective than single-agent treatment in decreasing tumour growth in xenografts of CCNE1-amplified/pik3ca-mutated USCs.

Conclusions:

Dual CCNE1/PIK3CA blockade may represent a novel therapeutic option for USC patients harbouring recurrent CCNE1-amplified/pi3kca-mutated tumours.