Efficacy and safety of nivolumab monotherapy in patients with unresectable clear cell sarcoma and alveolar soft part sarcoma (OSCAR Trial/NCCH1510).

BACKGROUND: Clear cell sarcoma (CCS) and alveolar soft part sarcoma (ASPS) are rare, and standard systemic therapy is not established except for sunitinib in ASPS. It is known that CCS and ASPS have a common biological feature of melanoma and Xp11.2/TFE3 translocation renal cell carcinoma, and immune-checkpoint inhibitors (ICIs) are effective in these tumors. The authors conducted a phase 2 trial to evaluate the efficacy and safety of nivolumab for CCS and ASPS. METHODS: The number of patients expected to be enrolled was 15-25 and was determined based on the Bayesian design. The primary end point was the confirmed objective response rate (ORR) according to the central review and the secondary end points included ORR, progression-free survival (PFS), overall survival (OS), and safety. RESULTS: A total of 26 patients (CCS, 12; ASPS, 14) were enrolled. Efficacy and safety were analyzed on 25 and 26 patients, respectively. The minimum number of responses required for a positive conclusion regarding the efficacy was four. However, only one patient (4.0%) with ASPS had a partial response. Complete response, stable disease, progression disease, and not evaluable were 0%, 60%, 32%, and 4.0%, respectively. Adverse events of grade 3 or 4 occurred in 57.7% (15 of 26). The median PFS was 4.9 months (95% confidence interval [CI], 3.7-8.6 months) and the median OS was 15.8 months (95% CI, 8.2-not reached). CONCLUSIONS: The primary end point of the ORR was not met for CCS and ASPS on the central review. Further studies are needed to evaluate ICIs in patients with ASPS.

Trop-2 expression and the tumor immune microenvironment in cervical cancer.

OBJECTIVE: Trophoblast Cell Surface Antigen 2 (Trop-2) is a transmembrane glycoprotein that is overexpressed in various cancers, with immunological significance as a target for tumor-reactive T-cells. We aimed to investigate the association between the expression of Trop-2 and the tumor immune microenvironment in cervical cancer. METHODS: The study included 123 patients with cervical cancer who underwent primary surgery between 2000 and 2020 in our hospital. Trop-2 expression was evaluated using anti-Trop-2 monoclonal antibody clone MAB650. Immune biomarkers, including PD-L1 (22C3), CD3 (PS1), and CD8 (4B11), were also evaluated. Trop-2 and PD-L1 positivity were defined by an H-score ≥ 10 and a combined positive score (CPS) ≥1, respectively. Tumor-infiltrating lymphocytes (TILs) were assessed in the five selected independent areas. The correlation between Trop-2 expression and immune biomarkers was analyzed. RESULTS: The cohort comprised patients with squamous cell carcinoma (SCC) (54.5%) and non-SCC (45.5%). Trop-2 was positive in 84.6% of samples and more commonly expressed in SCC (SCC vs. non-SCC; 97.0% vs. 69.6%, p < 0.001). Intratumoral CD3+ and CD8 + TILs were significantly more common in Trop-2-positive cases (CD3, Mann-Whitney U = 383, p < 0.0001; CD8, U = 442, p < 0.0001). Additionally, significant positive correlations were found between the Trop-2 H-score and immune markers (CD3 + TILs, r = 0.295, p < 0.001; CD8 + TILs, r = 0.267, p = 0.001; PD-L1 CPS, r = 0.178, p = 0.025). No significant associations were detected between TILs and other clinicopathological features, including prognosis. CONCLUSION: Expression of Trop-2 in cervical cancer is associated with increased levels of intratumoral TILs, indicating the potential of Trop-2 targeted therapy alone or in combination with immune checkpoint inhibitors.

Folate Receptor Alpha Expression and the Tumor Immune Microenvironment in Patients with Cervical Cancer.

Folate receptor α (FRα) is a cell-surface protein and an attractive target for cancer treatment. We investigated the association between FRα expression and the tumor immune microenvironment in patients with cervical cancer. We examined whole tumor sections of 123 patients with cervical cancer: 67 and 56 sections of squamous cell carcinoma (SCC) and non-SCC, respectively. FRα expression was assessed using immunohistochemical staining with the anti-FRα monoclonal antibody clone 26B3. Programmed death-ligand 1 (PD-L1) expression was assessed using a combined positive score (CPS). The intratumoral CD3 and CD8 cell densities were calculated as the average number of positive cells in five independent areas. FRα-positivity was identified in 72.4% of the patients, and it differed by histology (SCC vs. non-SCC; 55.2% vs. 92.9%, P<0.001). PD-L1 status was positive (CPS ≥1) in 75.6% and was more commonly expressed in patients with SCC (SCC vs. non-SCC; 83.5% vs. 66.1%, P=0.02). FRα expression had a weak correlation with PD-L1 expression (r=-0.22, P<0.001) and CD8-positive cells (r=-0.19, P=0.03). FRα-positivity was more frequently observed in the PD-L1 CPS <10 group than in the PD-L1 CPS ≥10 group (81% vs. 64%, P=0.03). FRα-high was significantly associated with poor prognosis, especially in the PD-L1 CPS ≥10 groups (hazard ratio: 4.10, 95% confidence interval: 1.39-12.06, P=0.01). In conclusion, FRα expression was higher in patients with cervical cancer and PD-L1 CPS <10 than in those with CPS ≥10. Targeting FRα expression may be a potential therapeutic strategy for cervical cancer patients with low or negative PD-L1 expression.

Unveiling pembrolizumab effectiveness in diverse subtypes of MSI-high endometrial cancers.

OBJECTIVE: The efficacy of pembrolizumab in patients with microsatellite instability (MSI)-high cancers has been reported; however, the differences in efficacy according to the subtypes of MSI-high endometrial cancers (ECs) remain unclear. MSI-high ECs are classified into at least 3 groups based on their molecular characteristics: MLH1 hypermethylated, Lynch-like syndrome (LLS)-associated, and Lynch syndrome (LS)-associated cancers. This study aimed to investigate whether the efficacy of pembrolizumab differs among these 3 groups, and if so, whether EPM2AIP1 immunohistochemistry (IHC), which correlates with MLH1 promoter methylation, can be used to rule out MLH1 methylation cases. METHODS: This study included 12 patients with MSI-high EC who received pembrolizumab treatment. Patients were categorized into 3 groups based on MLH1 methylation analysis and the Amsterdam Criteria: MLH1 hypermethylated (sporadic [SP]), LLS-associated, and LS-associated. Patients' medical records were retrospectively reviewed, and the efficacy of treatment was evaluated based on the response rate using the Response Evaluation Criteria in Solid Tumors version 1.1. RESULTS: The overall response rate was 75% (3/4) in the SP group, while it was 100% including one complete response patient in the LLS-associated and the LS-associated group, respectively. The sensitivity and positive predictive value of EPM2AIP1 IHC for MLH1 methylation were 100% and 66.7%, respectively. CONCLUSION: Pembrolizumab may be more effective in LLS and LS-associated groups. EPM2AIP1 IHC was less predictive than MLH1 methylation analysis; however, it may be useful for ruling out MLH1 methylation cases due to its high sensitivity. Further studies are needed to determine whether EPM2AIP1 IHC can predict pembrolizumab efficacy.

HER2-negative or low expression as an unfavorable prognostic factor in patients with stage I/II uterine carcinosarcoma.

OBJECTIVE: Uterine carcinosarcoma (UCS) is uncommon high-grade endometrial cancer with limited treatment options. We evaluated the prognostic significance of human epidermal growth factor receptor 2 (HER2) expression and HER2 gene amplification within large cohorts of UCS, and clarify clinicopathologic characteristics of HER2-low UCS. METHODS: We examined HER2 protein expression in 148 patients of UCS using in vivo diagnostic HER2 immunohistochemistry (IHC) kits and HER2 gene amplification using fluorescence in situ hybridization (FISH) in 72 patients. RESULTS: HER2 IHC score was evaluated according to the latest American Society of Clinical Oncology/College of American Pathologists criteria for gastric cancer, which was negative in 41 patients, low expression of 1+ was observed in 57 patients, and HER2 high expression was observed in 50 patients (2+ in 38 and 3+ in 12 patients). There was no significant statistical difference in clinicopathological characteristics based on HER2 protein expression status. HER2 negative and low expression compared to high expression revealed poor overall survival in stage I/ II. The concordance between IHC and FISH results were relatively low compared to other cancer types (HER2 IHC score 1+, 2+, and 3+ were 5%, 15%, and 50%), and combining these results was not efficient as a prognostic factor in UCS. In contrast, the HER2 IHC score alone was a prognostic factor in stage I/II UCS. HER2 low group did not show specific clinicopathologic features. CONCLUSION: Since the HER2 IHC score low in advanced UCS is a predictive factor, stratification of UCS using HER2 IHC score for HER2 IHC score low group and developing adjuvant therapy may be proposed in the near future.

Clinicopathological and prognostic features of HER2-null and HER2-low advanced breast cancer treated with eribulin or capecitabine.

BACKGROUND: HER2-low populations constitute a heterogeneous group, and the cytotoxic anticancer agent efficacy based on HER2 status remains unclear. This study evaluated the clinicopathological features and outcomes of patients with advanced breast cancer showing HER2-low expression treated with eribulin or capecitabine, two treatment options after anthracycline and taxane treatment. METHODS: We retrospectively evaluated patients who were treated with eribulin or capecitabine between 2011 and 2015. HER2 status was evaluated according to the ASCO/CAP guidelines. RESULTS: No significant difference was observed in overall survival (OS; eribulin: hazard ratio [HR], 0.66; 95% CI 0.40-1.10; capecitabine: HR, 0.76; 95% CI 0.45-1.30) or progression-free survival (PFS; eribulin: HR, 1.13; 95% CI 0.72-1.78; capecitabine: HR, 0.90; 95% CI 0.56-1.44) between patients receiving eribulin (HER2-null: 35, HER2-low: 44) and those receiving capecitabine (HER2-null: 41, HER2-low: 33). Subgroup analysis revealed no significant differences in OS between the two groups in the hormone-positive and -negative populations for eribulin and capecitabine. HER2-null and HER2-low patients showed objective response rates (ORRs) of 22.5% and 9.1% (p = 0.09) overall, and 32.0% and 10.5% (p = 0.03), respectively, in hormone-positive cases among eribulin-treated patients. No response was observed in hormone-negative patients. Capecitabine treatment in HER2-null and HER2-low patients had overall ORRs of 26.8% and 15.2% (p = 0.23), respectively, with 27.3% and 16.1% (p = 0.28) for hormone-positive cases; and 25.0% and 0% (p = 1.0), respectively, for hormone-negative cases. CONCLUSIONS: Eribulin and capecitabine sensitivity may vary based on HER2 expression in patients with HER2-low and HER2-null breast cancer. Prognosis was similar between the HER2-low and the HER2-null groups.

Predicting Trabectedin Efficacy in Soft Tissue Sarcoma: Inflammatory Biomarker Analysis.

BACKGROUND/AIM: Trabectedin is used as a treatment for advanced-stage soft tissue sarcomas (STSs), particularly liposarcoma and leiomyosarcoma. Aside from its direct effect on tumor cells, trabectedin can affect the immune system in the tumor microenvironment. This study aimed to evaluate whether inflammatory biomarkers predict trabectedin efficacy in STSs. PATIENTS AND METHODS: We retrospectively reviewed the clinical features and outcomes of patients with STS treated with trabectedin at our institution between 2016 and 2020. The neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), platelet-to-lymphocyte ratio (PLR), and systemic inflammation response index (SIRI=neutrophil × monocyte/lymphocyte) were calculated based on the blood samples obtained prior to trabectedin treatment initiation. Analyses of overall survival (OS) and progression-free survival (PFS) were performed according to various factors. RESULTS: Of the 101 patients identified, 54 had L-sarcoma (leiomyosarcoma: 30; liposarcoma: 24), and 47 had other types of STSs. Elevated SIRI, NLR, PLR, LMR, and C-reactive protein (CRP) were associated with worse PFS (p<0.001, p=0.008, p=0.027, p=0.013, and p<0.001, respectively) according to the results of the univariate analysis. Multivariate analysis showed that elevated SIRI, other histology, and CRP were associated with poor PFS (p=0.007, p=0.008, and p=0.029, respectively). In addition, the multivariate analysis of OS showed that SIRI was an independent prognostic factor (hazard ratio=2.16, p=0.006). CONCLUSION: Pretreatment SIRI can be considered a biomarker for the prognostic prediction of patients with STS treated with trabectedin.