Peersen, Anina

PURPOSE Deficient mismatch repair/microsatellite instability (dMMR, MSI-H) in biliary tract cancers (BTCs) is observed in 1%-5% of tumors. MSI-H across solid tumors has demonstrated durable response to immune checkpoint inhibitors (ICIs) regardless of the anatomic location. Here, we describe clinical outcomes and surgical conversion of MSI-H BTC treated with ICIs. Patients and Methods We conducted a multicenter, retrospective analysis of BTC patients with dMMR/MSI-H between 2017 and 2024 at Mayo Clinic, University of Michigan, and University Hospitals Seidman Cancer Center. Outcomes of interest were surgical resection rate, rate of pathologic response, 2-year overall survival (OS; time from initiation of treatment to death/last follow-up), and time to treatment discontinuation (TTD; time from initiation of treatment to cessation because of any cause). Analyses were descriptive. RESULTS Thirty patients with MSI-H BTC were identified: 19 with cholangiocarcinoma, three with gallbladder cancer, and 8 with BTC undefined. The median age at diagnosis was 61.5 years (range, 26-86). Twenty-six (86.7%) patients had advanced stage at diagnosis. Twenty-seven patients (90%) received first-line systemic therapy, and 13 (48.1%) continued onto second line. Six patients (23.1%) were restaged to resectable from advanced disease after ICI therapy and underwent resection; all remained recurrence-free at last follow-up. Of these six patients, 3 (50%) achieved a pathologic complete response. Among those receiving first-line therapy, the median TTD was 9.9 months (95% CI, 5.7 to 14.5 months) and the 2-year OS was 73% (95% CI, 56% to 94%). CONCLUSION ICI therapy in patients with MSI-H BTC demonstrated durable response and downstaged some BTC to a resectable stage. dMMR/MSI-H should be performed up-front to guide treatment decisions.

554 Background: Atezo/Bev is the 1 st -line standard for advanced hepatocellular carcinoma (aHCC). Optimal 2 nd -line therapy post-Atezo/Bev remains undefined. This study evaluates continuation of atezolizumab with a MKI versus MKI alone in the 2 nd -line setting. Methods: This multicenter, randomized phase II trial enrolled patients with unresectable aHCC who progressed on Atezo/Bev. Patients were randomized 2:1 to atezolizumab plus MKI (cabozantinib or lenvatinib; Arm A) or MKI alone (Arm B). Stratification factors included MKI choice, viral etiology, and alpha-fetoprotein levels. Dual primary endpoints were overall survival (OS) and progression-free survival (PFS). Secondary endpoints included objective response rate (ORR), duration of response (DOR), and safety. With 84 death and 89 PFS events, from 122 patients, this trial had 80% power to detect a hazard ratio (HR) of 0.556 in OS and HR of 0.571 in PFS with a one-sided type I error (alpha) of 0.05 for each endpoint. Results: Twenty patients were accrued across 5 U.S. centers, between 01/2022 and 03/2025, before early closure due to slow accrual. Eighteen received treatment (Arm A: n=13; Arm B: n=5). Baseline characteristics: median age 68 yr, extrahepatic 56%, Hep B+ 0%, Hep C+ 33%, NASH 33% and CP A (5 to 6) 100%. MKIs used were cabozantinib (Arm A: 6/13; Arm B: 4/5) and lenvatinib (Arm A: 7/13; Arm B: 1/5). Median follow-up was 28.0 months (mo), with 14 deaths reported. Median (95% CI) OS were 13.9 (7.1-Not Estimable [NE]) and 6.2 (5.1-NE) mo (Arm A and B respectively); and that of PFS 4.3 (2.3-NE) and 4.1 (3.7-NE) mo. ORR was 7.7% (1/13) in Arm A (responder received lenvatinib) and 0% (0/5) in Arm B. Grade ≥3 adverse events (at least possibly related) occurred in 46.2% of Arm A and 60.0% of Arm B patients. G3+ events occurring in >10% of patients included hypertension, fatigue, anorexia, and ALT elevation in Arm A; and hypertension, hallucination, nausea, hypomagnesemia, hypokalemia, mucositis, AST increased and colitis in Arm B. Conclusions: In this limited cohort, continuation of atezolizumab with MKI showed relative activity and manageable safety in aHCC post-Atezo/Bev. The AE profile for atezo/MKI is consistent with the known profile of respective agents. These findings support further investigation of immunotherapy-based combinations in the 2nd-line setting. Clinical trial information: NCT05168163 .

392 Background: PAC+RAM is the standard second-line therapy for advanced GEA. However, PAC-related neuropathy is a major challenge, particularly since many pts have pre-existing neuropathy from prior platinum exposure. An effective “neuropathy-free” regimen remains an unmet need. We evaluated FTD-TPI+RAM as an alternative to PAC+RAM. Methods: This multi-center, randomized, phase II study enrolled GEA pts who progressed on or were intolerant to fluoropyrimidine+ platinum therapy. Pts were randomized to FTD-TPI+RAM (Arm A) or PAC+RAM (arm B) at a 1:1 ratio. The primary endpoint was progression-free survival (PFS), defined as time interval between randomization date and the date of disease progression or death; Secondary endpoints included overall survival (OS) and adverse events (AEs). The design hypothesized non-inferiority (NI) of Arm A to Arm B with a NI margin of hazard ratio 1.19. 90 PFS events from 116 pts provide 80% power with a one-sided alpha of 0.15. The interim futility analysis, conducted in December 2024 with 20 events, did not cross the futility boundary (Z statistic ≥ 1.172 ) and continued enrolling pts. The trial closed enrollment in March 2025 due to slow accrual. At the time of interim analysis, 20 events had occurred and the Z statistic was 0.4532. Final analysis included the 29 pts that were eligible, consented, randomized, and received any protocol treatment. Results: Among 29 pts (15 Arm A; 14 Arm B), baseline characteristics were balanced (in Arms A vs B, median age 64 vs 63; 80% vs 85.7% male; 86.7%% vs 78.6% White; 80% vs 78.6% ECOG 1). At data freeze of 8/4/2025, 26 PFS events were reported. Median PFS was 3.2 vs. 3.9 months in Arm A vs. Arm B (HR 1.37, 95% CI 0.61-3.02). NI was not demonstrated (Z =0.34, threshold for NI<-1.036). Median OS was 8.4 vs. 10.7 months, in Arms A and B, respectively. Grade ≥3 AEs occurred in 93% (Arm A) vs 71% (Arm B) with hematologic AEs occurring more frequently in Arm A than Arm B (53% vs 29%). Peripheral sensory neuropathy (any grade) occurred more frequently in Arm B (86%) vs. Arm A (47%). Conclusions: Although NI was not achieved due to early closure and small sample size, FTD-TPI+RAM was relatively safe and associated with less neuropathy compared with PAC+RAM. This regimen warrants further evaluation for pts in whom neuropathy limits taxane use. Clinical trial information: NCT04660760 .

Abstract Context Evidence on the evolution of cardiometabolic comorbidities following surgical remission of hypercortisolism is scarce. Objective To determine the impact of surgical remission on cardiometabolic comorbidities in patients with endogenous hypercortisolism and to identify factors associated with cardiometabolic improvement. Methods Prospective single-center cohort study (2019-2025) of adults with Cushing syndrome (CS) or mild autonomous cortisol secretion (MACS) with surgical remission of hypercortisolism. Outcomes included (1) changes in severity of hypertension, diabetes mellitus (DM), hyperlipidemia, and obesity between baseline, 3, and 12 months postremission and (2) factors associated with improvement in comorbidities. Results Among 357 patients (49% MACS, 36% pituitary CS, 10% adrenal CS, 5% ectopic CS; median age 53 years [interquartile range 42-62]; 81% women), 336 (94%) had hypertension, 241 (68%) had obesity, and 122 (35%) had DM. At a median of 12 months postsurgery, improvement in hypertension occurred in 70% (90/128) of patients with CS and 51% (60/117) of patients with MACS, DM in 90% (46/51) patients with CS and 37% (13/35) patients with MACS, and obesity in 79% (77/97) patients with CS and 20% (14/71) patients with MACS. In a multivariable analysis, higher baseline biochemical severity scores were associated with improvement in hypertension [odds ratio (OR) 1.3, 95% confidence interval (CI) 1.1-1.5), DM (OR 2.5, 95% CI 1.7-4.1), and obesity (OR 1.5, 95% CI 1.2-1.8) at a median of 12 months postremission of hypercortisolism. Conclusion Postsurgical improvement of cardiometabolic comorbidities was observed in both patients with CS and MACS. Higher baseline biochemical severity scores were associated with higher postremission improvement in comorbidities.

Abstract Disclosure: S.R. Chacko: None. C.A. Villavicencio Torres: None. K. Yu: None. S.G. Waguespack: None. L. Lu: None. Z. Belaya: None. T. Bandgar: None. A. Sada: None. O. Ragnarsson: None. B. Altieri: None. A. Newman: None. P. Vibhatavata: None. M. Tóth: None. E.V. Varlamov: None. C. Badiu: None. A. Paissan: None. M. St-Jean: None. H. Falhammar: None. N. Imamudeen: None. L. Haberbosch: None. M. Bobrowicz: None. A. Tabarin: None. R. Shah: None. M.R. Gadelha: None. A. Peersen: None. W.F. Young: None. J. Kaplan: None. J. Varghese: None. M.A. Habra: None. O. Golounina: None. G.A. Melnichenko: None. A.R. Lila: None. C. Yamichannaiah: None. I. Bancos: None. Context: Cushing syndrome (CS) due to ectopic ACTH secretion (EAS) is a rare condition, associated with severe hypercortisolism and consequent morbidity and mortality. Its varied and often emergent presentation make diagnosis and treatment challenging. Objectives: 1.Characterize clinical and biochemical presentation of EAS. 2.Describe the scope of hypercortisolism-related complications, overall and CS-specific mortality. 3.Identify factors associated with CS-specific mortality. Methods: We conducted a multicenter retrospective cohort study in patients with EAS at 37 centers. Outcomes were clinical/biochemical severity scores, complications, overall and CS-specific mortality. Results: In 1053 patients [median age at diagnosis 52 years (IQR 37-64), 57% women], metastatic disease was present at diagnosis in 585 (56%). The most common sources of EAS were bronchial neuroendocrine neoplasm (NEN) (304, 29%), pancreatic NEN (114, 11%) and small cell lung carcinoma (114, 11%), with the source of EAS being occult in 192 (18%). Clinical and biochemical severity scores were severe in 475 (45%) and 873 patients (92%) respectively. Hypokalemia was present in 819 patients (78%) in the year prior to diagnosis. Of 342 patients (32%) who had IPSS, 301 (88%) suggested an ectopic source, 7 (2%) a pituitary source, and 23 (7%) were non-diagnostic. Of 595 patients who had both functional and cross-sectional imaging, discordant findings were seen in 122 (21%), concordant lesion was seen on both in 326 (55%), and no lesion in 147 (25%). Of those with discordant results, cross-sectional imaging was accurate in 66 (54%) and functional imaging in 56 (46%).Management included medical therapy alone in 237 (23%), surgical excision of the source of EAS in 158 (15%), bilateral adrenalectomy in 77 (7%) and multimodal therapies in 498 patients (47%). Complications within 5 years after diagnosis included hospitalization related to CS or its therapy in 351 (33%), infection in 337 (32%), thromboembolic event in 102 (10%), cardiovascular event in 83 (8%) and cerebrovascular event in 27 (3%). During a median follow-up of 35 months (IQR 20-122) from CS diagnosis, death occurred in 462 patients (44%), with the cause of death related to CS in 149 (14%). CS-specific mortality was higher in metastatic compared with non-metastatic disease (19% vs. 7%, P&lt;0.001). On multivariable analysis of age, sex, clinical and biochemical severity, older age (HR 1.03, 95% CI: 1.02-1.04) and lower clinical severity score (HR 0.97, 95% CI: 0.94-0.99), were associated with higher CS-specific mortality. Conclusion: Our interim analysis, the largest worldwide, found that most patients with EAS had severe hypercortisolism and hypokalemia. Metastatic disease was present in 56%, and the source of EAS was occult in 18%. CS-related death occurred in 14%, emphasizing the need for urgent management. Presentation: Monday, July 14, 2025

Abstract Disclosure: S. Ahmadian: None. S.R. Chacko: None. S. Sharma Sharma: None. V.M. Fell: None. A. Peersen: None. E.J. Atkinson: None. K.L. Moehnke: None. Y. Chai: None. S.K. Grebe: None. A.D. Maus: None. I. Bancos: None. Background: Cortisol secretion follows a circadian pattern with highest concentrations in the morning, and lowest at night. Loss of circadian cortisol variation has been reported in patients with Cushing syndrome (CS), however, is scarcely investigated in patients with mild autonomous cortisol secretion (MACS). Outpatient assessment of late night and early morning salivary cortisol and cortisone may serve as a valuable diagnostic tool in patients with hypercortisolism. Methods: We conducted a single-center cross-sectional study of adults evaluated at our center between 04/2024 and 04/2025. The study included patients with Cushing’s syndrome (CS), mild autonomous cortisol secretion (MACS), and referent subjects without known adrenal disorders. Participants were provided with two cotton swabs (Salivettes) and instructed to collect saliva samples at two standardized time points: at bedtime (PM) and on waking (AM). Each swab was kept in the mouth for 2-2.5 minutes. Saliva was analyzed for cortisol and cortisone using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Delta cortisol and delta cortisone were defined as the difference between AM and PM concentrations for each individual and were calculated for all participants. Results: A total of 82 patients (32 with ACTH-dependent CS, 5 with ACTH-independent CS, and 45 with MACS), median age of 55 years [IQR 44-65], 63 (77%) women, and 71 referent subjects, median age of 34 years [IQR 28-42], 54 (76%) women, were included. Delta cortisol was higher in referents (median of 212 ng/dL, [IQR 157-358]) vs patients with CS (median 95 ng/dL [IQR -21-184]) or MACS (median 131 ng/dL, [IQR 91-229]). Similarly, delta cortisone was also highest in referents with a median of 828 ng/dL [IQR 612-1131] versus median of 211 ng/dL [IQR -58-468] in CS and 484 ng/dL [IQR 189-849] in MACS. When compared to referents in an age- and sex-adjusted linear regression model, delta cortisone was lower in both patients with CS (est -1.3 (95%CI -1.75 to -0.85), P&lt;0.001 and MACS (est -0.66, 95%CI of -1.17 to -0.16, P=0.010). Delta cortisol was lower in patients with CS (est -1.32, 95%CI -2.11 to -0.54, P=0.001), but not MACS (est -0.51, 95%CI -1.39 to 0.36). Conclusion: Patients with both CS and MACS demonstrate a blunted circadian salivary cortisol and cortisone secretion, as reflected by a lower delta cortisol and cortisone when compared to referent subjects. Assessment with delta salivary cortisone in patients with MACS may be more valuable than a standard of care late night salivary cortisol assessment. Presentation: Sunday, July 13, 2025

Abstract Disclosure: S. Sharma Sharma: None. J. Saini: None. S.R. Chacko: None. S. Ahmadian: None. V. Fell: None. S. Achenbach: None. A. Peersen: None. E. Atkinson: None. W.F. Young: None. I. Bancos: None. Context: Patients with MACS demonstrate an abnormal circadian cortisol secretion with mild nocturnal hypercortisolism that could impact sleep. Objectives: 1) To characterize sleep abnormalities and to identify factors associated with impaired sleep in patients with MACS. 2) To compare sleep abnormalities between patients with MACS and referent subjects. Methods: We conducted a single-center cross-sectional study of prospectively enrolled adults with MACS evaluated between August 31, 2020, and April 03, 2025. In parallel, we conducted a referent subject study between May 15, 2019, and May 02, 2023. Referent subjects were eligible if they had abdominal cross-sectional imaging without evidence of an adrenal mass. For patients with MACS, clinical and biochemical severity scores for hypercortisolism were calculated. In both groups, quality of life was assessed using Short Form-36 (SF-36), physical (PCS) and mental (MCS) component summaries. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), a global score of ≥5 was considered abnormal. Pearson correlations and linear regression models were used to explore associations with PSQI scores. Results: The total cohort included 167 patients with MACS and 89 referent subjects. No differences in age (median 60 vs 56 years, P= 0.122) and sex (71% vs 67% females, P= 0.523) were observed between patients with MACS and referents. However, median BMI was higher in patients with MACS (32 28 kg/m2 [IQR 28-38] vs 28 kg/m2 [IQR 24-32], P= &lt; 0.001). Patients with MACS had more impaired sleep than referent subjects (median PSQI 11 [IQR 7-15] vs 5 [IQR 3-7], P= &lt;0.001). In an age-, sex- and BMI- adjusted univariable analysis, lower PCS and MCS scores were associated with poor sleep in both referents (r= -0.45, P= &lt;0.001 and r= -0.29, P= 0.008) and patients with MACS (r= -0.36 and -0.38, P= &lt;0.001), however, the presence of obstructive sleep apnea (OSA) was not. In patients with MACS, both higher clinical and biochemical severity scores were associated with poor sleep (r=0.20, P=0.012) and (r= 0.15, P= 0.050). Multivariable analysis of age, sex, BMI, clinical severity and OSA demonstrated that women (est 2.35, P= 0.004), lower BMI (est -0.13, P= 0.014) and higher clinical severity score (est 0.17, P=0.026), but not OSA were associated with impaired sleep in patients with MACS. All PSQI subcomponents were higher in patients with MACS vs referents, indicating poor sleep-most significantly, sleep quality score (OR 3.93, 95% CI: 2.58-6.29), sleep disturbance score (OR 3.73, 95% CI: 2.28-6.37) and daytime dysfunction score (OR 4.74, 95% CI: 2.29-10.75). Conclusion: Patients with MACS report impaired sleep, and women with lower BMI and higher clinical hypercortisolism severity scores are more affected. Reversing abnormal nocturnal hypercortisolism may improve sleep. Presentation: Saturday, July 12, 2025

Abstract Context The impact of active hypercortisolism on sleep is incompletely characterized. Studies report impaired sleep in patients with Cushing syndrome (CS). Patients with mild autonomous cortisol secretion (MACS) demonstrate mild nocturnal hypercortisolism that could impact sleep. Objectives To characterize sleep abnormalities in patients with CS and MACS using the Pittsburgh Sleep Quality Index (PSQI), identify factors associated with poor sleep, and compare sleep abnormalities in patients with MACS vs referent subjects. Methods We conducted a single-center cross-sectional study of adults with active CS and MACS. Clinical and biochemical severity scores for hypercortisolism were calculated. Parallelly, we enrolled referent subjects. Quality of life was assessed using (1) the Short Form-36 (SF-36) in all participants and (2) the CushingQoL in patients with active hypercortisolism. Sleep quality was assessed using PSQI. Results PSQI was assessed in 154 patients with CS (mean 12, SD ±4.5), 194 patients with MACS (mean 11, SD 4.6), and 89 referents (mean 5, SD ±3.4). Patients with MACS exhibited shorter sleep duration, longer sleep latency, more severe daytime dysfunction, lower sleep efficiency, and a higher sleep medication use compared to referent subjects (P = &lt;.001 for all). Age-, sex, and body mass index-adjusted analysis demonstrated no differences in PSQI or its subcomponents between patients with CS and MACS (P &gt; .05 for all). In a multivariable analysis of patients with MACS, younger age, female sex, and higher clinical hypercortisolism severity score were associated with impaired sleep. In patients with CS, only younger age was associated with poor sleep. Conclusion Patients with MACS demonstrate sleep impairment that is similar to patients with CS. Younger women with higher clinical severity of MACS are more likely to have impaired sleep.

Abstract Background Unresectable hepatocellular carcinoma (uHCC) is a leading cause of cancer death. FDA-approved first-line systemic therapies include atezolizumab/bevacizumab (atezo/bev) and durvalumab/tremelimumab (durva/treme); however, there is a lack of comparative data. Methods We reviewed outcomes of patients with uHCC who initiated atezo/bev or durva/treme between 2017 and 2024, across six institutions. Overall survival (OS) and time to treatment discontinuation (TTD) were analyzed using the Kaplan–Meier and Cox models, adjusting for baseline characteristics. Results Four hundred fifty-two uHCC pts were included. Median age: 68 years; 77% male; 81% white. Most common etiologies were viral hepatitis (38.9%) and metabolic dysfunction-associated steatohepatitis (19.5%). Disease progression was the primary reason for treatment discontinuation, atezo/bev (56%) and durva/treme (42%). Outcomes were not statistically significant (median OS [month, m]: 14.0 vs 14.6 [P = .66]; median TTD [m]: 4.9 vs 3.9 [P = .42] for atezo/bev vs durva/treme). Outcomes were significantly different between Child-Pugh classes (CP: A, B7, B8/9, C) respectively, median OS(m): 19.0, 6.1, 5.1, 2.0 (P &lt; .001); median TTD(m): 6.1, 2.3, 3.0, 1.3 (P &lt; .001). Conclusions In this real-world study of uHCC, no significant difference in clinical outcomes was observed between atezo/bev and durva/treme in the first-line setting. CP scores were a key prognostic variable with both regimens.

e23317 Background: mCRC poses significant challenges, particularly in patients (pts) who progress after multiple lines of therapy. Limited effective treatment options are available in the advanced chemotherapy-refractory setting. The FRESCO-2 trial demonstrated that Fruq, a selective VEGFR inhibitor, provides meaningful overall survival (OS) benefit in pts with refractory mCRC. However, there is limited real-world evidence regarding Fruq's efficacy in patients treated after approved third-line therapies. Methods: This retrospective, multi-site cohort study evaluated outcomes in 33 mCRC pts who received Fruq following treatment with Rego and/or TAS-102 with or without bevacizumab. Patients were stratified into two groups: Fruq as a second late-line therapy, after either Rego or TAS-102, (27 patients) and as a third late-line therapy, after both Rego and TAS-102, (6 patients). Overall survival (OS) was calculated from Fruq initiation to death, while time to treatment discontinuation (TTD) was defined as the duration from Fruq initiation to cessation for any reason, including death. Survival analysis was performed using the Kaplan-Meier method to estimate median survival, and the comparison between groups were done using the log-rank test. Results: Among the 33 pts, the median age was 58 years (range: 35–84), with 57.6% being male. Hepatic metastases were present in 78.8%, and 60.6% had left-sided primary tumors. RAS mutations were observed in 63.6%, and 97% were BRAF wild-type. Median OS was significantly longer in pts who received Fruq as a second late-line therapy (7.2 months) compared to those receiving it as a third late-line therapy (4.0 months) (p = 0.039). Median TTD was similar between groups (2.4 vs. 2.8 months, p = 0.916). Conclusions: This real-world analysis highlights the clinical benefit of Fruquintinib in mCRC patients following treatment with Regorafenib and/or TAS-102. The data suggest flexibility in treatment choices, with Fruquintinib showing improved OS when used earlier in the treatment sequence. These findings underscore the importance of exploring optimal sequencing strategies and evaluating Fruquintinib as a potential option before other approved agents in the refractory setting. Clinical outcomes with fruquintinib as second vs. third late-line therapy. Fruq as Second Late-Line Fruq as Third Late-Line p-value Median OS 7.2 months 4 months 0.039 Median TTD 2.4 months 2.8 months 0.916 OS: Overall Survival; TTD: Time to Treatment discontinuation.