Metastatic urinary tract cancer (mUTC) is challenging to treat in older adults due to comorbidities. We compared the clinical courses of younger and older (≥70 years) adults with mUTC receiving ...first-line (1L) systemic therapy in a tertiary cancer center. Baseline clinical characteristics, treatments received, tolerability, and survival outcomes were analyzed. Among 212 patients (103 older vs. 109 younger), the older patients had lower hemoglobin at baseline (84% vs. 71%, p = 0.03), the majority were cisplatin-ineligible (74% vs. 45%, p < 0.001), received more immunotherapy-based treatments in the 1L (52% vs. 36%, p = 0.01), received fewer subsequent lines of treatment (median 0 vs. 1, p = 0.003), and had lower clinical trial participation (30% vs. 18%, p = 0.05) compared to the younger patients. When treated with 1L chemotherapy, older patients required more dose adjustments (53.4% vs. 23%, p = 0.001) and received fewer cycles of chemotherapy (median 4 vs. 5, p= 0.01). Older patients had similar OS (11.2 months vs. 14 months, p = 0.06) and similar rates of treatment-related severe toxicity and healthcare visits, independent of the type of systemic treatment received, compared to younger patients. We conclude that select older adults with mUTC can be safely treated with immunotherapy and risk-adjusted regimens of chemotherapy with tangible survival benefits.
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Background: Older adults with locally advanced or mUC often do not receive optimal first-line (1L) therapy (Rx) and subsequent treatments (Lara et al. ASCO 2016). There are limited randomized ...data for age-appropriate Rx in older mUC adults. Through our real-world study, we describe the clinical characteristics, treatment patterns, and outcomes among pts with mUC, comparing older to younger adults receiving 1L systemic Rx. Methods: This retrospective IRB-approved study included pts receiving care between 2014 and 2023 at the University of Utah, Huntsman Cancer Institute, a tertiary care National Cancer Institute-Designated Comprehensive Cancer Center. Eligible pts had a confirmed diagnosis of mUC and received 1L chemotherapy or 1L immunotherapy-based regimens. Based on age at receipt of 1L Rx, pts aged 70 years or above were grouped in the ‘older’ group, while rest were included in the ‘younger’ cohort. Survival and Rx-related outcomes of those enrolled inwere excluded. Overall survival (OS) between the two groups was compared using Kaplan-Meier and Cox Regression analysis. All statistical analyses were implemented in R-Studio (v.4.2). Results: We identified 212 eligible mUC pts (103 older vs. 109 younger). Older pts received more immunotherapy-based Rx in the 1L (52.4% vs 35.7%, p=0.02), were more likely to be (73.6% vs. 45.4%, p<0.001), less likely to receive subsequent lines of Rx (median; range: 0 (0-3) vs 1 (0-5), p=0.005) and had lower clinical trial participation (69.9% vs 81.6%, p=0.04)compared to younger pts. For survival outcomes and treatment-related analysis, 160 patients (72 older vs. 88 younger) undergoing approved standard of care were included. Among mUC treated with 1L chemotherapy (n=108), more pts required dose adjustments in older group (23/43 vs 15/65 younger). Older adults received less number of cycles of chemotherapy (median; range: 4 (0-6) vs 5 (1-12), p= 0.03). Older pts had OS comparable to younger pts (11.2 mos vs. 14 mos, p=0.06). Pts from both age groups had similar rates of Rx-related toxicity and healthcare visits, independent of the type of systemic Rx. Conclusions: Older pts with mUC tend to be cis-ineligible and have lower bone marrow reserve. Nevertheless, select pts can be treated with risk-adjusted regimens of chemotherapy and with immunotherapy with comparable outcomes to younger mUC pts in terms of toxicity and outcomes. Validated tools to predict vulnerabilities and excessive chemotherapy-related toxicity in older adults with mUC are available and may help mitigate toxicity by informing Rx adjustments.
Abstract The role of human epidermal growth factor receptor-2 (HER2) protein and the inhibition of its oncogenic signaling pathway, ERBB2, is well defined and found to be beneficial in combination ...with standard chemotherapies in breast and certain gastro-intestinal cancers. Targeting the ERBB2 pathway has had unclear or inconsistent results in early trials in bladder cancer (BLCA) and the efficacy of its combination with cisplatin, a standard BLCA chemotherapy, is not known. In this study, we identify the transcriptomic oncogenic signatures that correlate with ERBB2 signaling in BLCA, explore how HER2 expression in BLCA cell lines correlates with treatment response in vitro, and evaluate the potential of ERBB2 inhibition in combination with cisplatin for BLCA. We analyzed the tumor transcriptome from the Cancer Genome Atlas (TCGA) study of BLCA with single sample Gene Set Enrichment Analyses (ssGSEA) for Hallmark and Oncogenic gene sets. We performed multiple Pearson correlation analyses of HER2 protein levels and ERBB2 signaling with other signaling pathways in the TCGA BLCA tumors and adjusted the significance for multiple comparisons using the Benjamini-Hochberg method. Immunoblotting was used to assess HER2 protein levels across a panel of bladder cancer cell lines. We then assessed cell viability and colony formation upon exposure to the specific ERBB2 inhibitor, tucatinib. Synergy between cisplatin and tucatinib in BLCA cell lines was evaluated using the Chou-Talalay method. In the TCGA BLCA dataset, HER2 protein positively correlates with ERBB2 signaling with a Pearson correlation coefficient of 0.45 and an adjusted p-value of 1.73E-17. ERBB2 signaling has multiple significant positive and negative correlations. ERBB2 signaling negatively correlates with the DNA repair gene set with a Pearson coefficient of -0.5 and an adjusted p-value of 1.40E-22. HER2 protein expression varies greatly between bladder cancer cell lines: HT-1197 and UMUC3 have lower HER2 expression, with HT-1376, T24, RT4, 5637, and SW780 showing higher HER2 expression. HT-1197 and RT4 had the lowest IC50s for tucatinib and showed a strong response to low doses of tucatinib in the colony formation assay. Cisplatin and tucatinib have synergetic growth inhibition (combination index <1) at low concentration levels in the HT-1197 and SW780 cell lines. Multiple oncogenic pathways coexist with ERBB2 signaling in BLCA. The varied response to specific ERBB2 inhibition and the lack of correlation of the response with HER2 protein level in cell lines alludes to alternative oncogenic pathways. A strong negative correlation of ERBB2 signaling with the DNA response pathway in the TCGA BLCA dataset, combined with preclinical evidence of synergy between tucatinib and cisplatin, indicates a potential for development of the combination as a clinical treatment strategy and warrants further study. Citation Format: Constance Caparas-Spaugy, Chris Stubben, Ken Boucher, Bingjian Feng, Aaron Atkinson, David Nix, Bradley Cairns, Sumati Gupta. ERBB2 signaling and inhibition in bladder cancer abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4696.
