Receipt Of Neoadjuvant Chemotherapy Research Articles

Trends and Outcomes of Neoadjuvant Chemotherapy for Clinical Stage T1 Pancreatic Cancer.

Neoadjuvant chemotherapy (NC) for early pancreatic ductal adenocarcinoma (PDAC) remains controversial. We investigate the adoption of NC and its impact on survival in clinical T1 (cT1) PDAC. National Cancer Database (2006-2017) was reviewed for cT1 PDAC. Patients receiving NC and surgery were compared with patients undergoing upfront surgery (US). A total of 5886 patients were included. NC use increased from 4.8% in 2006 to 18.8% in 2017. The NC group (n = 618) versus the US group (n = 5268) had: younger age (66 years vs. 68 years), smaller tumor size (2 cm vs. 2.2 cm), more pancreas head tumors (77% vs. 70.6%), lower lymph-vascular invasion (25.9% vs. 40.6%), and less lymph node positivity (43.6% vs. 54.5%), p < 0.001. Factors associated with receipt of NC were: younger age, recent year of diagnosis, and treatment at an academic program. In the NC group versus the US group, median OS was 35.2 months versus 28.3 months, p < 0.001. Factors associated with improved survival included: well differentiated pathology, R0 surgical margins, and receipt of chemotherapy. In cT1 PDAC, chemotherapy is associated with improved survival. In a surgery-first approach, only 59% of patients receive adjuvant chemotherapy. These data suggest consideration of neoadjuvant therapy for early pancreatic cancer.

Current National Treatment Trends for Gastric Adenocarcinoma in the United States.

The treatment of gastric adenocarcinoma (GA) continues to evolve. While neoadjuvant chemotherapy (NAC) has demonstrated emerging benefit, the optimal treatment regimen, and sequence remain to be firmly established. Patients with nonmetastatic GA who underwent resection were identified within the 2020 National Cancer Database. Patients were compared between the mutually exclusive treatment groups of NAC, neoadjuvant chemoradiotherapy (NCRT), adjuvant chemotherapy, adjuvant chemoradiotherapy (CRT), and surgery only. The primary endpoint was receipt of NAC or NCRT. Patients were 1-to-1 propensity score matched for receiving any neoadjuvant therapy. Multivariable logistic regression was used to identify predictors of receipt of any neoadjuvant therapy and receipt of any adjuvant therapy. Twenty-five thousand and seventy-three patients were included in the analysis. Patients were treated with NAC (25.0%), NCRT (31.4%), adjuvant chemotherapy (6.5%), adjuvant CRT (12.6%), and surgery only (24.5%). Compared to 2006-2011, patients diagnosed between 2012 and 2017 experienced the greatest increases in NAC (18.6% vs. 29.0%; p < 0.001) and NCRT (25.0% vs. 35.5%; p < 0.001). Median OS was 44.9 months. OS was longest for patients who received any neoadjuvant therapy compared to those receiving adjuvant or surgery only (51.0 vs. 42.4 vs. 38.0 months, respectively; p < 0.001). Patients who were Black, in the lowest income quartile or treated at lower volume facilities were less likely to receive NAT (all p < 0.001). There has been significant acceleration in the use of neoadjuvant therapy for GA. Currently, NCRT followed by surgery are the most common treatment sequences in the United States. Additional trials are needed to further define the optimal treatment sequence.

Improving the quality and guideline concordance of multidisciplinary gastric cancer care in a safety net hospital.

314 Background: Gastric cancer is a leading cause of cancer death worldwide and disproportionally affects people of East Asian and Latin American ethnicities. This study aimed to implement and evaluate an intervention to improve the quality and guideline concordance of multidisciplinary gastric cancer care at a public safety net hospital, Zuckerberg San Francisco General Hospital (ZSFG). Methods: A quality improvement (QI) intervention was developed and evaluated by pre-post comparison of clinical data. (1) An in-depth chart review of all patients with gastric adenocarcinoma in 2017-2019 (n=17) evaluated concordance with evidence-based guidelines and quality metrics. (2) Multidisciplinary meetings identified barriers to high quality care and established targets for improvement. (3) A clinical algorithm tailored for ZSFG was disseminated to standardize gastric cancer management. (4) A post-intervention chart review was conducted of all patients from 2021-2022 (n=22). (5) Descriptive statistics and pre-post comparison of QI metrics with Chi square and Kruskal Wallis tests were performed. Results: Pre-intervention clinical data and multidisciplinary input identified gaps in care: variation in provider knowledge and practices, rapidly evolving guidelines, limited access to advanced diagnostic modalities, and non-standardized surgical documentation. After implementation of a standardized approach to address these gaps, pre-post improvement was seen in rates of tumor board presentation (36.3% vs. 85.7%, P= 0.033), use of endoscopic ultrasound (9.09% vs. 64.2%, P= 0.017), pre-treatment nodal staging (27.2% vs. 78.5%, P= 0.030), receipt of neoadjuvant chemotherapy (20% vs. 80%, P=0.007 ), documentation of lymphadenectomy type (25% vs. 100%, P= 0.015), and a trend toward reduced time to PET/CT scan (median, 8.5 weeks pre vs 7.1 weeks post, P= 0.268). Conclusions: A QI intervention was successfully implemented to standardize gastric cancer care at ZSFG. Significant improvements were seen in all targeted metrics except time to outside PET scan. Potential confounders affecting pre-post care quality included personnel changes in a small workforce and the COVID-19 pandemic. Nevertheless, our intervention led to sustained improvements in practice patterns. We aim to replicate this success with other malignancies. Category Pre-Intervention Target Post-Intervention P value* Tumor Board% cM0 cases presented 36% (n=11) &gt;90% 86% (n=14) 0.033 Endoscopic ultrasound (EUS)% cM0 cases referred for clinical staging 9% (n=11) &gt;90% 64% (n=14) 0.017 Nodal staging (with EUS or PET) 27% (n=11) N/A 79% (n=14) 0.030 Receipt of neoadjuvant chemotherapy% eligible patients 20% (n=10) &gt;80% 80% (n=10) 0.007 Surgery documentationLymphadenectomy type (i.e., D1 or D2) 25% (n=8) 100% 100% (n=7) 0.015 Time from diagnosis to PET/CT (median) 8.5 wks &lt;5 wks 7.1 wks 0.268 *Chi square test, Kruskal-Wallis test.

Factors associated with delays in receipt of neoadjuvant chemotherapy in patients with operable breast cancer.

126 Background: Delays in neoadjuvant chemotherapy initiation (NACTI) after breast cancer (BC) diagnosis have been associated with worse outcomes. We evaluated incidence and predictors of delays of NACTI among high clinical risk patients treated with NACT on a national level. Methods: We conducted a retrospective cohort study using the National Cancer Database. Eligibility included age ≥18 years, diagnosis of non-metastatic BC between 1/1/2010 – 12/31/2020, who were treated with NACT within 180 days of diagnosis. Patients who received neoadjuvant endocrine therapy were excluded. Time to chemotherapy (TTC) in days was recorded. Patients were categorized into sub-cohorts by receptor status and clinical stage: 1) Hormone Receptor positive/HER-2 negative (HR+/HER2-) and were lymph node (LN) LN+; 2) HER-2 positive (HER2+) cT2+ or LN+; and 3) triple negative BC (TNBC) cT2+ or LN+. Multivariable logistic regression, adjusted for demographic, socioeconomic and tumor characteristics, was used to identify characteristics associated with delays &gt; 60 days from diagnosis to NACTI. Multiple imputation was used for missing data. Results: We identified 145,697 eligible patients, 74% were White, 18% were Black, 3.3% were Asian, and 4.6% were Other/Unknown. Across all racial categories, 9.2% were Hispanic. Median age at diagnosis was 52 years (range 18-90), median TTC was 32 days (range 0-180), and 10% had a delay &gt; 60 days. There were 40,345 patients in the HR+/HER2- cohort, 56,868 in the HER2+ cohort, and 48,484 in the TNBC cohort; 12%, 9.0%, and 8.9% (p &lt; 0.001) had a delay in NACTI, respectively. In multivariable analysis among the HR+/HER2- sub-cohort, characteristics associated with delays in NACTI included Black race (OR 1.71, 95%CI 1.57-1.86) and Hispanic ethnicity (OR 1.76, 95%CI 1.60-1.94) compared to White and non-Hispanic patients. Patients with Medicare, Medicaid, or who were uninsured were more likely to be delayed (OR 1.44 95%CI 1.30-1.58, 2.10, 95%CI 1.92-2.29, 2.28, 95%CI 1.99-2.61) compared to those with commercial insurance. Results were similar in the HER2+and TNBC cohorts, as seen (Table). Conclusions: Among patients with operable BC who received NACT, patients who were Black, Hispanic, had Medicaid or no insurance had as high as a twofold increase in odds of a delay in NACTI. Targeted interventions to address these racial and socioeconomic disparities are necessary to ensure equitable care. Multivariable logistic regression adjusted for demographic, socioeconomic, and tumor characteristics variables (n = 145,697). HR+/HER2-N= 40,345 HER2+N= 56,868 TNBCN= 48,484 OR 95%CI OR 95%CI OR 95%CI Black Race 1.71 1.57-1.86 1.89 1.74-2.04 1.90 1.76-2.06 Hispanic Ethnicity 1.76 1.60-1.94 2.18 2.00-2.36 2.00 1.80-2.21 Medicare 1.44 1.30-1.58 1.46 1.34-1.61 1.45 1.32-1.61 Medicaid 2.10 1.92-2.29 2.13 1.96-2.31 2.14 1.96-2.34 No Insurance 2.28 1.99-2.61 2.36 2.07-2.70 2.25 1.96-2.59

Niraparib first-line maintenance therapy in patients with newly diagnosed advanced ovarian cancer: final overall survival results from the PRIMA/ENGOT-OV26/GOG-3012 trial

The phase 3 PRIMA/ENGOT-OV26/GOG-3012 trial met its primary endpoint. Niraparib first-line maintenance significantly prolonged progression-free survival (PFS) among patients with newly diagnosed advanced ovarian cancer (aOC) that responded to first-line platinum-based chemotherapy, regardless of homologous recombination deficiency (HRD) status. Final overall survival (OS) results are reported. Patients were randomized 2:1 to niraparib or placebo, stratified by response to first-line treatment, receipt of neoadjuvant chemotherapy, and tumor HRD status. After reaching 60% target maturity, OS was evaluated via a stratified log-rank test using randomization stratification factors and summarized using Kaplan-Meier methodology. OS testing was hierarchical (overall population first, then the homologous recombination-deficient [HRd] population). Other secondary outcomes and long-term safety were assessed; an updated, ad hoc analysis of investigator-assessed PFS was also conducted (cutoff date, 08Apr2024). Median follow-up was 73.9 months. In the overall population, the OS hazard ratio (HR) was 1.01 (95% CI, 0.84-1.23; P= 0.8834) for niraparib (n= 487) versus placebo (n;= 246). In the HRd (n= 373) and homologous recombination-proficient (n= 249) populations, the OS HRs were 0.95 (95% CI, 0.71-1.29) and 0.93 (95% CI 0.69-1.26), respectively. Subsequent poly(ADP-ribose) polymerase inhibitor therapy was received by 11.7% and 15.8% of niraparib patients and 37.8% and 48.4% of placebo patients in the overall and HRd populations, respectively. The 5-year PFS rate numerically favored niraparib in the overall (niraparib, 22%; placebo, 12%) and HRd populations (niraparib, 35%; placebo, 16%). Myelodysplastic syndromes/acute myeloid leukemia incidence was <2.5% (niraparib, 2.3%; placebo, 1.6%). No new safety signals were observed. In patients with newly diagnosed aOC at high risk of recurrence, there was no difference in OS between treatment arms. In the HRd population, patients alive at 5 years were twice as likely to be progression free with niraparib treatment than placebo. Long-term safety remained consistent with the established niraparib safety profile.

Evaluating Treatment Patterns and the Role of Neoadjuvant Chemotherapy in Plasmacytoid Urothelial Carcinoma: Insights from a Combined National and Institutional Series.

Plasmacytoid urothelial carcinoma (PUC) is a rare histologic subtype of urothelial carcinoma of the bladder (BC). Our objective was to characterize treatment patterns and outcomes of PUC in the NCDB and our recent institutional experience. The NCDB was queried for localized PUC cases between 2004 and 2020. Patients with PUC from a single institution (Yale School of Medicine) were also incorporated from 2021 onwards to not double-count patients. The primary outcomes were overall survival and treatment trends. A total of 146 patients were included, 123 from NCDB and 23 from Yale. The median overall survival (mOS) was 28 [IQR 7.5, 50.3] months, 23 [IQR 8.4, 46.3] months for the NCDB patients, and 36 [IQR 4.3, 68.1] for the Yale patients. The mOS for patients receiving neoadjuvant chemotherapy (NAC) was 60.0 [28.0, 91.9] vs. 14.8 months [0, 34.3] for patients without NAC, p = 0.038, though the benefit was not preserved in a Cox proportional hazard analysis incorporating the clinical stage, receipt of NAC, and age. The peritoneum was the most common site of metastasis (78.3%), followed by the liver and bones. Our findings underscore the formidable challenge posed by PUC, emphasizing its limited response to current therapies. Despite higher pT0 rates with NAC, the OS benefit remains inconclusive, highlighting the need for more effective treatments.

Impact of Location of Residence and Distance to Cancer Centre on Medical Oncology Consultation and Neoadjuvant Chemotherapy for Triple-Negative and HER2-Positive Breast Cancer.

Despite consensus guidelines, most patients with early-stage triple-negative (TN) and HER2-positive (HER2+) breast cancer do not see a medical oncologist prior to surgery and do not receive neoadjuvant chemotherapy (NAC). To understand barriers to care, we aimed to characterize the relationship between geography (region of residence and cancer centre proximity) and receipt of a pre-treatment medical oncology consultation and NAC for patients with TN and HER2+ breast cancer. Using linked administrative datasets in Ontario, Canada, we performed a retrospective population-based analysis of women diagnosed with stage I-III TN or HER2+ breast cancer from 2012 to 2020. The outcomes were a pre-treatment medical oncology consultation and the initiation of NAC. We created choropleth maps to assess the distribution of the outcomes and cancer centres across census divisions. To assess the relationship between distance to the nearest cancer centre and outcomes, we performed multivariable regression analyses adjusted for relevant factors, including tumour extent and nodal status. Of 14,647 patients, 29.9% received a pre-treatment medical oncology consultation and 77.7% received NAC. Mapping demonstrated high interregional variability, ranging across census divisions from 12.5% to 64.3% for medical oncology consultation and from 8.8% to 64.3% for NAC. In the full cohort, compared to a distance of ≤5 km from the nearest cancer centre, only 10-25 km was significantly associated with lower odds of NAC (OR 0.83, 95% CI 0.70-0.99). Greater distances were not associated with pre-treatment medical oncology consultation. The interregional variability in medical oncology consultation and NAC for patients with TN and HER2+ breast cancer suggests that regional and/or provider practice patterns underlie discrepancies in the referral for and receipt of NAC. These findings can inform interventions to improve equitable access to NAC for eligible patients.

Editorial Comment on “Social Vulnerability and Receipt of Neoadjuvant Chemotherapy in Patients Undergoing Radical Cystectomy for Bladder Cancer”

Editorial Comment on “Social Vulnerability and Receipt of Neoadjuvant Chemotherapy in Patients Undergoing Radical Cystectomy for Bladder Cancer”

Disparities in neoadjuvant chemotherapy for pancreatic adenocarcinoma with vascular involvement

BackgroundMultiagent neoadjuvant chemotherapy (NAT) has been linked with improved survival for locally advanced (LA) or borderline resectable (BR) pancreatic ductal adenocarcinoma (PDAC). However, the existence of disparities in its utilization remains to be elucidated. MethodsAll adults with PDAC were tabulated from the 2011–2017 Nationwide Cancer Database. Tumor vascular involvement was determined using the clinical T stage and CS_EXTENSION variables. The significance of temporal trends was calculated using Cuzick's non-parametric test. A Cox proportional hazard model was used to assess the impact of NAT utilization on hazard of two-year mortality. A logistic regression model was developed to determine factors associated with receipt of NAT. ResultsOf 3811 patients meeting inclusion criteria, 50.8 % received NAT. NAT utilization significantly increased over the study period, from 31.7 % in 2011 to 81.1 % in 2017 (p < 0.001). NAT was associated with significantly reduced two-year mortality (Hazards Ratio 0.34, 95 % Confidence Interval [CI] 0.18–0.67).After adjustment, younger (Adjusted Odds Ratio [AOR] 0.97/year, CI 0.96–0.98) and Black (AOR 0.65, CI 0.48–0.89; ref: White) patients demonstrated reduced odds of NAT. Furthermore, patients with Medicare (AOR 0.73, CI 0.59–0.90; ref: Private) or Medicaid insurance (AOR 0.67, CI 0.46–0.97; ref: Private) had lower odds of NAT, as did those treated at non-academic institutions (Community: AOR 0.42, CI 0.35–0.52, Integrated: 0.68, CI 0.54–0.85) or in the lowest education quartile (AOR 0.52, CI 0.29–0.95; ref: Highest). ConclusionsWe identified increasing utilization of NAT for BR/LA pancreatic adenocarcinoma. Despite being linked with significantly reduced two-year mortality, socioeconomic disparities affect odds of NAT.

Factors associated with delays in receipt of neoadjuvant chemotherapy in patients with operable breast cancer.

e13541 Background: Delays in neoadjuvant chemotherapy initiation (NACTI) after breast cancer (BC) diagnosis have been associated with worse outcomes. We evaluated incidence and predictors of delays of NACTI among high clinical risk patients treated with NACT on a national level. Methods: We conducted a retrospective cohort study using the National Cancer Database. Eligibility included age ≥18 years, diagnosis of non-metastatic BC between 1/1/2010 – 12/31/2020, who were treated with NACT within 180 days of diagnosis. Patients who received neoadjuvant endocrine therapy were excluded. Time to chemotherapy (TTC) in days was recorded. Patients were categorized into sub-cohorts by receptor status and clinical stage: 1) Hormone Receptor positive/HER-2 negative (HR+/HER2-) and were lymph node (LN) LN+; 2) HER-2 positive (HER2+) cT2+ or LN+; and 3) triple negative BC (TNBC) cT2+ or LN+. Multivariable logistic regression, adjusted for demographic, socioeconomic and tumor characteristics, was used to identify characteristics associated with delays &gt; 60 days from diagnosis to NACTI. Multiple imputation was used for missing data. Results: We identified 145,697 eligible patients, 74% were White, 18% were Black, 3.3% were Asian, and 4.6% were Other/Unknown. Across all racial categories, 9.2% were Hispanic. Median age at diagnosis was 52 years (range 18-90), median TTC was 32 days (range 0-180), and 10% had a delay &gt; 60 days. There were 40,345 patients in the HR+/HER2- cohort, 56,868 in the HER2+ cohort, and 48,484 in the TNBC cohort; 12%, 9.0%, and 8.9% (p &lt;0.001) had a delay in NACTI, respectively. In multivariable analysis among the HR+/HER2- sub-cohort, characteristics associated with delays in NACTI included Black race (OR 1.71, 95%CI 1.57-1.86) and Hispanic ethnicity (OR 1.76, 95%CI 1.60-1.94) compared to White and non-Hispanic patients. Patients with Medicare, Medicaid, or who were uninsured were more likely to be delayed (OR 1.44 95%CI 1.30-1.58, 2.10, 95%CI 1.92-2.29, 2.28, 95%CI 1.99-2.61) compared to those with commercial insurance. Results were similar in the HER2+ and TNBC cohorts, as seen in Table. Conclusions: Among patients with operable BC who received NACT, patients who were Black, Hispanic, had Medicaid or no insurance had as high as a twofold increase in odds of a delay in NACTI. Targeted interventions to address these racial and socioeconomic disparities are necessary to ensure equitable care. Multivariable logistic regression adjusted for demographic, socioeconomic and tumor characteristics variables (n= 145,697). [Table: see text]

Social Vulnerability and Receipt of Neoadjuvant Chemotherapy in Patients Undergoing Radical Cystectomy for Bladder Cancer

To evaluate the association between a population-level measure of social determinants of health, the Centers for Disease Control and Prevention Social Vulnerability Index (SVI), and receipt of neoadjuvant chemotherapy in patients with muscle-invasive bladder cancer (MIBC) undergoing radical cystectomy. We queried our institutional database for patients with nonmetastatic MIBC treated with radical cystectomy between 2000 and 2022. Patients were assigned an SVI via ZIP code of residence and grouped into quintiles of SVI (i.e. least vulnerable to most vulnerable). Multivariable logistic regression was performed to evaluate the association between SVI and receipt of neoadjuvant chemotherapy, adjusting for age, race, gender, and cancer stage. A sub-analysis was performed to evaluate the association between subthemes of SVI (socioeconomic status, household composition/disability, race/ethnicity/language, and housing/transportation) and receipt of neoadjuvant chemotherapy. Of the 978 patients identified, 490 (50.1%) received neoadjuvant chemotherapy. Patients that received neoadjuvant chemotherapy had a lower SVI, were younger, and had >cT2 stage (all, p<0.05). The most vulnerable patients had lower odds of receiving neoadjuvant chemotherapy (OR 0.61, 0.39 - 0.95) compared to the least vulnerable patients. Analysis of subthemes of SVI demonstrated similar associations by socioeconomic status (OR 0.56, 0.36 - 0.86) and household composition/disability (OR 0.57, 0.33 - 0.99). Adverse social determinants of health, or social vulnerability, is associated with suboptimal and disparate utilization of neoadjuvant chemotherapy in patients with MIBC undergoing radical cystectomy. Strategies for identifying vulnerable populations may allow for more targeted interventions that would improve equity in bladder cancer care.

Income Disparities in Survival and Receipt of Neoadjuvant Chemotherapy and Pelvic Lymph Node Dissection for Muscle-Invasive Bladder Cancer.

Background: Muscle-invasive bladder cancer (MIBC) is a potentially fatal disease, especially in the setting of locally advanced or node-positive disease. Adverse outcomes have also primarily been associated with low-income status, as has been reported in other cancers. While the adoption of neoadjuvant cisplatin-based chemotherapy (NAC) followed by radical cystectomy (RC) and pelvic lymph node dissection (PLND) has improved outcomes, these standard-of-care treatments may be underutilized in lower-income patients. We sought to investigate the economic disparities in NAC and PLND receipt and survival outcomes in MIBC. Methods: Utilizing the National Cancer Database, a retrospective cohort analysis of cT2-4N0-3M0 BCa patients with urothelial histology who underwent RC was conducted. The impact of income level on overall survival (OS) and the likelihood of receiving NAC and PLND was evaluated. Results: A total of 25,823 patients were included. This study found that lower-income patients were less likely to receive NAC and adequate PLND (≥15 LNs). Moreover, lower-income patients exhibited worse OS (Median OS 55.9 months vs. 68.2 months, p < 0.001). Our findings also demonstrated that higher income, treatment at academic facilities, and recent years of diagnosis were associated with an increased likelihood of receiving standard-of-care modalities and improved survival. Conclusions: Even after controlling for clinicodemographic variables, income independently influenced the receipt of standard MIBC treatments and survival. Our findings identify an opportunity to improve the quality of care for lower-income MIBC patients through concerted efforts to regionalize multi-modal urologic oncology care.

Abstract 800: Spatial accessibility of gynecologic oncologists and time to surgery in a diverse cohort of women with ovarian cancer in Northern California

Abstract Introduction: To expand our understanding of factors contributing to racial and ethnic disparities in ovarian cancer outcomes, we examined the association between spatial accessibility of gynecologic oncologists and time from cancer diagnosis to surgery in the KPROCS Study, a diverse cohort of women diagnosed with ovarian cancer between 2000-2018 at Kaiser Permanente Northern California (KPNC). Spatial medical accessibility is a component of healthcare access that captures the proximity and availability of healthcare resources in the area. Methods: Ovarian cancer cases were identified through the KPNC Cancer Registry. Demographic and clinical information was extracted from KPNC databases. Neighborhood characteristics from the California Neighborhoods Data System were linked to the residential addresses of cases at the time of diagnosis. Spatial medical accessibility was measured using the 2-step floating catchment area method based on the location of the infusion centers where KPNC gynecologic oncologists practice and the residence location of cohort members. We used generalized estimating equations with independent correlation structure and robust standard errors to examine the association between spatial accessibility of gynecologic oncologists and time to ovarian cancer surgery, adjusting for year and age at diagnosis, stage, histotype, race, ethnicity, neighborhood socioeconomic status (nSES), and receipt of neoadjuvant chemotherapy. Results: The cohort comprised 4,910 women with ovarian cancer, of whom 3,304 had surgery at KPNC. Of this group, 13% were Hispanic, 14% were non-Hispanic (NH) Asian American women, 5% NH Black women, and 67% NH White women. The proportion of women residing in areas of the lowest spatial accessibility of gynecologic oncologists was highest among NH White women (26%) and women residing in the highest quintile of nSES (29%). The median time from diagnosis to surgery was 4 days (interquartile range 22 days). In adjusted analyses, not including the information on spatial accessibility, the time from diagnosis to surgery was 5.1 days longer (95% CI 1.5, 8.7) for NH Black women than NH White women. After adding information on spatial accessibility, this time did not considerably change, resulting in a 5.3-day (95% CI 1.7, 8.9) difference. In this model, the lowest quintile of spatial accessibility of gynecologic oncologists was associated with a longer time from diagnosis to surgery, but this association was not statistically significant (0.4 days difference, 95% CI -1.3, 2.0). Summary: In our preliminary analyses, spatial accessibility of gynecologic oncologists was not found to be a contributing factor to the disparity in time from diagnosis to surgery between NH Black and NH White women. Further analyses will examine time from diagnosis to chemotherapy overall and stratified by racial and ethnic groups. Citation Format: Ekaterina Chirikova, Pushkar P. Inamdar, Valerie McGuire, Salma Shariff-Marco, Valerie S. Lee, Lindsay J. Collin, Carola T. Sanchez-Diaz, Juraj Kavecansky, C Bethan Powell, Jennifer A. Doherty, Lawrence H. Kushi, Elisa V. Bandera, Scarlett L. Gomez. Spatial accessibility of gynecologic oncologists and time to surgery in a diverse cohort of women with ovarian cancer in Northern California [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 800.

Proximal gastric cancer—time for organ-sparing approach?

IntroductionA steady increase in gastroesophageal junction and proximal gastric cancer (GC) incidence has been observed in the West. Given recent advances in neoadjuvant chemotherapy (NAC), we sought to characterize short- and long-term outcomes of patients with proximal GC who underwent total (TG) versus proximal gastrectomy (PG). MethodsPatients with stage II/III proximal GC who underwent curative intent treatment between 2009 and 2019 were identified using National Cancer Database (NCDB). Multivariable analysis was used to identify oncological outcomes following TG versus PG. ResultsAmong 7,616 patients with GC who underwent surgical resection, PG and TG were performed on 5,246 (68.8%) and 2,370 (31.2%) patients, respectively. Patients who underwent PG were more likely to receive NAC (TG: 52.3% vs. PG: 64.5%)(p<0.001). On pathologic analysis, patients who underwent TG were more likely to have pT4 tumors (TG: 11.7% vs. PG: 3.1%), metastatic lymph nodes (TG: 64.6% vs. PG: 60.4%), and >16 lymph nodes evaluated (TG: 64.1% vs. PG: 53.1%), yet a lower likelihood of negative resection margins (TG: 86.6% vs. PG: 90.0%)(all p<0.001). While gastrectomy procedure type did not impact long-term survival, receipt of NAC was associated with OS among patients who underwent TG (5-year OS, NAC: 43.5% vs. no NAC: 24.6%) and PG (5-year OS, NAC: 43.1% vs. no NAC: 26.7%)(both p<0.001). ConclusionsPG may be an alternative surgical approach to TG in well-selected patients with proximal GC after administration of preoperative systemic chemotherapy.

The role of neoadjuvant chemotherapy for patients with variant histology muscle invasive bladder cancer undergoing robotic cystectomy: Data from the International Robotic Cystectomy Consortium

ObjectiveTo assess the role of neoadjuvant chemotherapy (NAC) before robot-assisted radical cystectomy (RARC) for patients with variant histology (VH) muscle-invasive bladder cancer (MIBC). MethodsRetrospective review of 988 patients who underwent RARC (2004–2023) for MIBC. Primary outcomes included the utilization of NAC among this cohort of patients, frequency of downstaging, and discordance between preoperative and final pathology in terms of the presence of VH. Secondary outcomes included disease-specific (DSS), recurrence-free (RFS), and overall survival (OS). ResultsA total of 349 (35%) had VH on transurethral resection or at RARC. The 4 most common VH subgroups were squamous (n = 94), adenocarcinoma (n = 64), micropapillary (n = 34), and sarcomatoid (n = 21). There was no difference in OS (log-rank: P = 0.43 for adenocarcinoma, P = 0.12 for micropapillary, P = 0.55 for sarcomatoid, P = 0.29 for squamous), RFS (log-rank: P = 0.25 for adenocarcinoma, P = 0.35 for micropapillary, P = 0.83 for sarcomatoid, P = 0.79 for squamous), or DSS (log-rank P = 0.91 for adenocarcinoma, P = 0.15 for micropapillary, 0.28 for sarcomatoid, P = 0.92 for squamous) among any of the VH based on receipt of NAC. Patients with squamous histology who received NAC were more likely to be downstaged on final pathology compared to those who did not (P < 0.01). ConclusionOur data showed no significant difference in OS, RFS, or DSS for patients with VH MIBC cancer who received NAC before RARC. Patients with the squamous variant who received NAC had more pathologic downstaging compared to those who did not. The role of NAC among patients with VH is yet to be defined. Results were limited by small number in each individual group and lack of exact proportion of VH.

Abstract A137: Drive time to physicians and outcomes for bladder cancer

Abstract Introduction: Poor geographic access to cancer care providers can delay treatment and limit access to high quality care. Previous research has shown that for patients with bladder cancer, time to cystectomy and receipt of neoadjuvant chemotherapy are associated with improved survival. Travel burden may be an important barrier to timely guideline-concordant treatment and is particularly relevant for residents of rural areas, which are often medically underserved. This study examines the association between drive time to medical oncologists and urologists and clinical outcomes for muscle-invasive bladder cancer (MIBC) patients. Data and Methods: We used information on physician location from the Centers for Medicare and Medicaid Services and patient-level data from the 2010-2016 Pennsylvania Cancer Registry linked to Pennsylvania Healthcare Cost Containment Council (PHC4) inpatient discharge data through 2018. We examined patients in Pennsylvania with a first lifetime bladder cancer diagnosis who underwent radical cystectomy at a non-federal short-term general hospital identified in PHC4. Outcomes examined were surgery within 90 days, receipt of neoadjuvant chemotherapy, 90-day mortality and 90-day readmission. We estimated multivariable linear regression models at the patient level. Our primary exposures were the natural log number of minutes from the patient’s home census tract centroid to the nearest medical oncologist and the nearest urologist. We controlled for patient age, sex, race/ethnicity, tumor size, tumor node involvement, and Elixhauser comorbidity index. We included a control for whether the patient received neoadjuvant chemotherapy in models estimating the association between drive times and cystectomy within 90 days. We also controlled for area-level characteristics, including ZIP code median and area deprivation index quartile. Standard errors were clustered at the county level.Results: The study included 954 patients with MIBC, 1,520 medical oncologists, and 976 urologists in Pennsylvania. Mean (SD) drive time to the nearest oncologist was 17.1 (11.4) minutes and median drive time was 14.4 minutes. Mean drive time to the nearest urologist was 13.9 (9.2) minutes and median drive time was 11.7 minutes. A 30-minute increase in drive time to the nearest urologist was associated with a 12.5 percentage point lower likelihood of undergoing cystectomy within 90 days (95% CI: -24.3 to -0.6). A 30-minute increase in drive time to the nearest oncologist was associated with an 11.9 percentage point lower likelihood of receiving neoadjuvant chemotherapy (95% CI: -23.4 to -0.4). Drive time was not significantly associated with 90-day mortality or readmission within 90 days. Conclusions: Drive time to both oncologists and urologists is associated with timely receipt of guideline-recommended care for patients with MIBC. Understanding the impact of geographic access to medical oncologists and urologists on clinical outcomes for patients with MIBC can inform providers and policymakers in addressing geographic equity in cancer care. Citation Format: Sruthi Muluk, Coleman Drake, Zhaojun Sun, Manisha Bhattacharya, Bruce Jacobs, Lindsay M. Sabik. Drive time to physicians and outcomes for bladder cancer [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr A137.

Neoadjuvant Chemotherapy Improves Oncological Outcomes and Long-Term Survival Among Elderly Patients with Locally Advanced Gastric Cancer: A Propensity Score Matched Analysis.

In the USA, approximately half of newly diagnosed patients with GC are 75 years or older. The objective of the current population-based study was to investigate the impact of neoadjuvant chemotherapy (NAC) on the outcomes of elderly patients with locally advanced GC. Patients aged > 75 years were identified from the National Cancer Database (NCDB). The primary outcome of the study was overall survival (OS). Secondary outcomes included lymph node (LN) harvest, surgical margin status, and 30-day mortality. To minimize the effect of selection bias on the assessed outcome between the two study groups (NAC versus no NAC), propensity score matching (PSM) was performed. After PSM, a total of 1958 patients were included in both groups. NAC utilization increased from 2013 to 2019 (21% versus 42.7%, ptrend < 0.001). On pathologic analysis, patients who received NAC were more likely to have ≥ 16 LNs evaluated (NAC 60.1% versus no NAC 55.5%, p = 0.044) and negative resection margins (NAC 88.6% versus no NAC 83%, p = 0.001). Patients who received NAC were alsoless likely to experience 30-day mortality following resection (NAC 4.1% versus no NAC 7.1%). Receipt of NAC was associated with improved 1-year (73.9% versus 68.3%), 3-year (48.2% versus 43.5%), and 5-year OS (36.9% versus 30.5%) compared with patients who underwent upfront surgery (p = 0.01). Receipt of NAC was associated with improved oncological outcomes among elderly patients undergoing resection for locally advanced GC.

Impact of Neoadjuvant Chemotherapy on Pathologic Downstaging in Patients With Variant Histology Undergoing Radical Cystectomy

IntroductionVariant histology (VH) bladder cancer is often associated with poor outcomes and the role of neoadjuvant chemotherapy (NAC) remains incompletely defined. Our objective was to determine comparative pathologic downstaging at radical cystectomy (RC) following NAC for patients with and without VH. Patients and MethodsPatients who underwent RC at 2 tertiary referral centers (1996-2018) were included. Patients with VH (sarcomatoid, nested, micropapillary, plasmacytoid) were matched 1:2 to patients with pure urothelial carcinoma by age, sex, clinical T (cT)stage, clinical N (cN)stage, cystectomy year and receipt of NAC. The primary outcome was pathologic downstaging (pT-stage < cT-stage). The differential impact of NAC on pathologic downstaging between VH and non-VH was assessed using multivariable logistic regression with interaction analysis. Results225 VH and 437 non-VH patients were included. One hundred twenty-eight of six hundred sixty-two (19.3%) patients experienced downstaging, including 54/121 (44.6%) patients who received NAC and 74/542 (13.2%) patients who did not (P < .01). Rates of downstaging after NAC for subgroups were: 45/78 (57.7%) urothelial, 3/8 (37.5%) sarcomatoid, 2/12 (16.7%) nested, 3/14 (21.4%) micropapillary, and 1/8 (12.5%) plasmacytoid. Collectively, 9/42 (21.4%) of VH patients who received NAC were downstaged. On multivariable analyses, NAC was associated with increased likelihood of downstaging in the overall cohort (OR 5.25, 95% CI, 3.29-8.36, P < .0001) and this effect was not modified by VH versus non-VH histology (P = .13 for interaction). VH patients had worse survival outcomes compared to non-VH (P < 0.01 for all). ConclusionWhen comparing patients with VH to matched pure urothelial carcinoma controls, VH did not have an adverse effect on downstaging following NAC. VH patients should not be excluded from NAC if otherwise eligible.

Perioperative discordance in mesothelioma cell type after pleurectomy/decortication-a possible detrimental effect of neoadjuvant chemotherapy due to epithelial to mesenchymal transition?

To evaluate the accuracy of preoperative histological assessment, factors affecting the accuracy and the subsequent effect on postoperative survival after surgical treatment for malignant pleural mesothelioma(MPM). We analysed the perioperative course of patients who underwent surgery for MPM in a single institution over a 5-year period. The primary endopoint was to evaluate the proportion of histological discordance between preoperative assessment and postoperative histology, while the secondary end-point was to evaluate its prognostic effect on postoperative survival after surgical treatment. One-hundred and twenty-nine patients were included in this study. Histological discordance between preoperative assessment and postoperative histology was found in 27 of 129 patients(20.9%):epithelial to biphasic/sarcomatoid(negative discordance) in 24, and biphasic to epithelial(positive discordance) in 3(p-value < 0,001).All 24 patients exhibiting epithelial-to-mesenchymal transition(EMT) had received neoadjuvant chemotherapy(p-value : 0,006).In the 34 patients who underwent upfront surgery, only one case(2.9%) of EMT was identified(p-value : 0,127).EMT was not associated with a less invasive method of biopsy(p-value : 0.058) nor with the volume or maximum diameter of the biopsy(p-value : 0,358 and 0,518, respectively) but it was significantly associated with the receipt of neoadjuvant chemotherapy(p-value : 0,006).At median follow-up of 17 months(IQR : 11.0-28.0),50(39%) patients are still alive. Overall survival was significantly reduced in those patients who received neoadjuvant chemotherapy and exhibited discordance(EMT) compared to those who did not : 11(95% CI : 6.2-15.8)months vs 19(95% CI : 14.2 -23.8) months(p-value < 0,001). In addition, there was no difference in overall survival between those who received neoadjuvant chemotherapy and those who had upfront surgery : 16(95% CI : 2.5-19.5)months vs 30(95% CI : 11.6-48.4)months(p-value : 0,203). The association of neoadjuvant chemotherapy with perioperative histological discordance can be explained by EMT, which lead to worse survival. Therefore, there is an argument for the preferential use of upfront surgery in the treatment of otherwise resectable MPM.

Successful Breast Conservation After Neoadjuvant Chemotherapy in Lobular Breast Cancer: The Role of Menopausal Status in Response to Treatment.

While neoadjuvant chemotherapy (NAC) has been shown to increase rates of breast conservation surgery (BCS) for breast cancer, response rates in invasive lobular carcinoma (ILC) appear lower than other histologic subtypes. Some data suggest higher response rates to NAC in premenopausal versus postmenopausal patients, but this has not been studied in ILC. We evaluatedthe rates of successful BCS after NAC in patients with ILC stratified by menopausal status. We analyzed data from a single-institution cohort of 666 patients with stage I-III hormone receptor positive HER-2 negative ILC. We used t-tests, chi-squared tests, and multivariable logistic regression to investigate rates of NAC use, attempted BCS, and associations between NAC and successful BCS by menopausal status. In 217 premenopausal and 449 postmenopausal patients, NAC was used more often in the premenopausal group (15.2% vs. 9.8%, respectively, p = 0.041). Among those who attempted breast conservation (51.3% of pre- and 64.8% of postmenopausal cohorts), NAC was not associated with successful BCS in either group. Interestingly, for postmenopausal patients, receipt of NAC was significantly associated with increased rates of completion mastectomy in those who had positive margins at thefirst attempt at BCS. NAC was not associated with successful BCS in either premenopausal or postmenopausal patients with ILC. Although premenopausal patients were more likely to receive NAC, these data suggest that menopausal status may not be a good predictor of response to chemotherapy. Better predictors of response and more efficacious treatment for patients with ILC are needed.