Citations

Abstract Internal herniation through the foramen of Winslow is one of the rarest types of hernia. As signs and symptoms can be quite generalized, prompt identification can prove difficult, leading to increased morbidity and mortality. The majority of reported cases of foramen of Winslow herniation result in obstruction of either the small or large bowel requiring operative intervention. As they are so rare, there is no established treatment algorithm for foramen of Winslow hernias. We present here a unique case of cecal herniation through the foramen of Winslow resulting in biliary compression and acute cholecystitis without bowel obstruction that was managed with laparoscopic cholecystectomy and right hemicolectomy.

ABSTRACT Background In recent years, transcatheter implantation devices to restrict pulmonary arterial flow have emerged as a potential alternative to surgical pulmonary artery banding. Case Presentation A term male was diagnosed with critical aortic stenosis (AS) and severely reduced left ventricle (LV) systolic function. He underwent aortic balloon valvuloplasty on day 2 of life, resulting in some antegrade flow, but LV ejection fraction only improved to 15%. He remained ductal dependent for systemic perfusion. Pulmonary over‐circulation ensued with systemic steal evident in his second week of life. On day 14, he underwent a transcatheter stage 1 procedure including the placement of bilateral pulmonary flow restrictor (PFR) devices and ductal stenting. Post‐procedure, he improved clinically, weaned off respiratory support, and transitioned to oral feeds while awaiting cardiac transplant. Twelve days later, he received a donor heart, with an uneventful recovery. He is now 3 years post‐transplant and has excellent graft function, and his transplant course has been unremarkable. Conclusion Transcatheter‐based palliation for a neonate with critical AS, utilizing endoluminal PFRs, proved effective in stabilizing the infant and successfully bridging him to transplant. This highlights an opportunity for the utilization of PFRs in neonatal conditions where control of pulmonary blood flow is imperative as a bridge to transplantation.

AbstractBackgroundProgressive supranuclear palsy (PSP) can present with different clinical variants which show distinct, but partially overlapping, patterns of neurodegeneration and tau deposition in a PSP network of regions, including cerebellar dentate, superior cerebellar peduncle, midbrain, thalamus, basal ganglia, and frontal lobe. We sought to determine whether disruptions in functional connectivity within this PSP network measured using resting‐state functional MRI (rs‐fMRI) differed between PSP‐Richardson’s syndrome and the cortical and subcortical variants of PSP.MethodStructural MRI and rs‐fMRI scans were collected for 40 PSP‐RS, 24 PSP‐cortical (12 speech and language; 10 corticobasal syndrome; 2 frontal) and 36 PSP‐subcortical (18 parkinsonism; 11 progressive gait freezing; 6 postural instability; 1 oculomotor) participants who met the Movement Disorder Society PSP clinical criteria (Table 1). Ninety‐six participants underwent flortaucipir‐PET scans. MRIs were processed using CONN Toolbox. Functional connectivity between seeds placed throughout the PSP network was compared between each PSP group and 83 healthy controls, and between the PSP groups, covarying for age and sex.ResultsConnectivity was reduced throughout the network in PSP‐RS compared to controls (Figure 1A), involving cerebellar dentate, midbrain nuclei, subthalamic nuclei, basal ganglia, thalamus, and frontal regions. Frontal regions showed reduced connectivity to other regions in the network in PSP‐cortical, including substantia nigra and superior cerebellar peduncle. Disruptions in connectivity in PSP‐subcortical were less pronounced, with the strongest disruption between the pallidum and putamen. When PSP groups were compared to each other (Figure 1B), PSP‐RS had lower connectivity from the thalamus and cerebellar dentate to the cortex compared to PSP‐subcortical and from the thalamus to substantia nigra than PSP‐cortical. PSP‐subcortical had lower connectivity from the subthalamic nucleus to caudate than PSP‐RS and from the subthalamic nucleus to substantia nigra than PSP‐cortical and higher connectivity from the thalamus to the prefrontal cortex than both the other variants. Voxel‐based analyses replicated these patterns. There was moderate evidence that tau uptake in the PSP network regions influenced connectivity between these regions in PSP.ConclusionsPatterns of disrupted functional connectivity revealed both variant‐specific and shared disease pathways among PSP variants, providing insight into the disease heterogeneity beyond patterns of atrophy.

AbstractBackgroundSelf‐administered cognitive assessments demonstrate usability and ability to detect cognitive decline in Alzheimer’s disease, but usability in other neurodegenerative diseases is understudied. We investigated whether Mayo Test Drive (MTD), a self‐administered multi‐device compatible cognitive assessment platform, demonstrates usability and correlation with traditional neuropsychological tests in a pilot study of individuals with progressive supranuclear palsy (PSP).MethodEleven individuals with PSP (mean age = 69.6±7.2 years; mean education = 15.3±2.7 years; 72.7% male; 90.9% white; PSP Rating Scale [PSPRS] = 32.4±15.5) enrolled in a Neurodegenerative Research Group study at Mayo Clinic participated. Participants completed neurological evaluation, traditional neuropsychological assessment, in‐person self‐administered MTD comprised of the Stricker Learning Span and Symbols Test, and a MTD usability questionnaire with quantitative and qualitative questions. Participants received diagnoses of PSP clinical variants per Movement Disorders Society‐PSP criteria. Seven participants had PSP‐Richardson, two had PSP‐postural instability, and two had PSP‐parkinsonism. We used descriptive analyses to examine usability questions, qualitative analyses for free text responses, and Spearman correlations to analyze associations between MTD and traditional tests of global cognition and five cognitive domains.ResultTen of eleven patients completed MTD (average completion time [minutes] = 22.2±6.5). Study staff terminated one participant’s session early due to an appointment conflict; we excluded this participant from analyses. Six participants completed MTD with tablets and four used smartphones. Participants reported high ease completing MTD (9.00±1.76 on 0‐10 scale) and comfortability using their devices (9.40±1.58). All participants reported they could complete MTD independently, with one participant indicating need for assistance with hyperlinks and three reporting need for assistance with QR codes. Qualitative data suggested three participants had motoric difficulty using the tablets; these individuals had the greatest PSPRS symptom severity, although MTD performance was not correlated with the PSPRS (rho = ‐.122; p>.05). MTD performance significantly correlated with the MoCA (rho = 0.88) and tests of attention, executive, and visuospatial function (Table).ConclusionIn a MTD usability pilot for participants with PSP, participants reported high ease and comfort completing MTD independently; those with greater motor symptoms had more difficulty navigating technology. Additionally, performances on MTD were correlated with the MoCA and other in‐person assessments, demonstrating convergent validity.

AbstractBackgroundSelf‐administered cognitive assessments demonstrate usability and ability to detect cognitive decline in Alzheimer’s disease, but usability in other neurodegenerative diseases is understudied. We investigated whether Mayo Test Drive (MTD), a self‐administered multi‐device compatible cognitive assessment platform, demonstrates usability and correlation with traditional neuropsychological tests in a pilot study of individuals with progressive supranuclear palsy (PSP).MethodEleven individuals with PSP (mean age = 69.6±7.2 years; mean education = 15.3±2.7 years; 72.7% male; 90.9% white; PSP Rating Scale [PSPRS] = 32.4±15.5) enrolled in a Neurodegenerative Research Group study at Mayo Clinic participated. Participants completed neurological evaluation, traditional neuropsychological assessment, in‐person self‐administered MTD comprised of the Stricker Learning Span and Symbols Test, and a MTD usability questionnaire with quantitative and qualitative questions. Participants received diagnoses of PSP clinical variants per Movement Disorders Society‐PSP criteria. Seven participants had PSP‐Richardson, two had PSP‐postural instability, and two had PSP‐parkinsonism. We used descriptive analyses to examine usability questions, qualitative analyses for free text responses, and Spearman correlations to analyze associations between MTD and traditional tests of global cognition and five cognitive domains.ResultTen of eleven patients completed MTD (average completion time [minutes] = 22.2±6.5). Study staff terminated one participant’s session early due to an appointment conflict; we excluded this participant from analyses. Six participants completed MTD with tablets and four used smartphones. Participants reported high ease completing MTD (9.00±1.76 on 0‐10 scale) and comfortability using their devices (9.40±1.58). All participants reported they could complete MTD independently, with one participant indicating need for assistance with hyperlinks and three reporting need for assistance with QR codes. Qualitative data suggested three participants had motoric difficulty using the tablets; these individuals had the greatest PSPRS symptom severity, although MTD performance was not correlated with the PSPRS (rho = ‐.122; p>.05). MTD performance significantly correlated with the MoCA (rho = 0.88) and tests of attention, executive, and visuospatial function (Table).ConclusionIn a MTD usability pilot for participants with PSP, participants reported high ease and comfort completing MTD independently; those with greater motor symptoms had more difficulty navigating technology. Additionally, performances on MTD were correlated with the MoCA and other in‐person assessments, demonstrating convergent validity.

OBJECTIVE To evaluate a regimen of inhaled Technosphere insulin (TI) plus insulin degludec in adults with type 1 diabetes, who prestudy were predominately using either an automated insulin delivery (AID) system or multiple daily insulin injections (MDI) with continuous glucose monitoring. RESEARCH DESIGN AND METHODS At 19 sites, adults with type 1 diabetes were randomly assigned to TI plus insulin degludec (N = 62) or usual care (UC) with continuation of prestudy insulin delivery method (N = 61) for 17 weeks. RESULTS Prestudy, AID was used by 48% and MDI by 45%. Mean ± SD HbA1c was 7.57% ± 0.97% at baseline and 7.62% ± 1.06% at 17 weeks in the TI group and 7.59% ± 0.80% and 7.54% ± 0.77%, respectively, in the UC group (adjusted difference 0.11%, 95% CI −0.10 to 0.33, P value for noninferiority = 0.01). HbA1c improved from baseline to 17 weeks by >0.5% (5.5 mmol/mol) in 12 (21%) in the TI group and in 3 (5%) in the UC group and worsened by >0.5% (5.5 mmol/mol) in 15 (26%) in the TI group and in 2 (3%) in the UC group. The most common TI side effect was a brief cough; eight participants discontinued TI due to side effects. CONCLUSIONS In adults with type 1 diabetes, HbA1c after 17 weeks with a regimen of TI and degludec was noninferior to UC, which consisted predominately of either AID or MDI. TI should be considered an option for people with type 1 diabetes, particularly those who are motivated to further reduce postprandial hyperglycemia.

Introduction: Complex karyotype (CK, ≥3 chromosome (chr) abnormalities (abn)) is an important adverse prognostic indicator in chronic lymphocytic leukemia (CLL). CK at diagnosis (dx) of CLL, particularly with major structural chr abn (i.e. unbalanced translocation, add, marker, ring chr), called type-2 CK (CK2), has been associated with an increased risk of Richter transformation (RT) (Visentin Haematologica 2022). RT is defined as development of aggressive lymphoma, most often large B-cell lymphoma, in the setting of CLL. In patients (pts) with relapsed/refractory CLL treated with ibrutinib, CK as a continuous variable and the presence of polyploidy were independent predictors for RT. CK is a common finding at the time of RT, and high-CK (≥5) has been associated with short survival in RT, although previous studies predominantly included pts with prior chemoimmunotherapy (CIT) administration for their CLL. The prognostic significance of CK in pts with RT whose prior CLL-directed therapies include only non-CIT, as is the current standard of care for CLL, has not been evaluated. Methods: We conducted a multicenter, retrospective analysis of pts from 14 academic centers. Pts with RT diagnosed between 6/2011 to 6/2023, who had CLL-directed treatment that did not include prior CIT, with stimulated karyotype data available, were included. Pts who did not receive treatment for their CLL prior to developing RT were not included. Baseline pt, disease, and cytogenetics data were collected via chart review at time of CLL diagnosis and at the development of RT. Karyotype abn up to 20 were counted on both CLL tissue (peripheral blood or bone marrow) and RT tissue using IWGMC guidelines (Chun Leuk Res 2010). CK was categorized as CK1 (balanced abn, deletion, aneusomies) or CK2. Polyploidy was defined as ≥58 chrs. Karyotype was considered evolved if one or more chr abn were seen in a follow-up sample of CLL tissue that were not seen at CLL dx.TP53 disruption was defined as presence of del(17p) or TP53 mutation. Overall survival (OS) was measured from RT dx and estimated using the Kaplan-Meier method. Cox regression model was used to identify prognostic factors associated with OS. Results: A total of 64 eligible pts were identified. Median age at RT dx was 65 years (range 40-89) and 71.9% of pts were male. Of those evaluated (n=49), 79.6% had unmutated IGVH. Median number of therapies for CLL prior to RT was 1 (range 1-5) and included BTK inhibitor (n=37), BCL2 inhibitor (n=3), both (n=18), or other non-CIT treatment (n=6). At CLL diagnosis, 54.7% of pts had a CK, and the median number of chr abn was 3 (range 0-20). Of those with CK, 96.9% had a CK2, and 6.3% had a polyploid subclone. TP53 disruption was found in 46% of pts. At time of RT, chr analysis of CLL tissue was available for 38 pts and showed 78.9% had a CK, and the median number of chr abn was 8 (range 0-20). Polyploidy was found in 29.6%. TP53 disruption (46 pts evaluated) was found in 52.2%. Karyotype evolution from dx (35 pts evaluated) occurred in 74.3% of pts. In RT tissue, of those evaluated (n=29), 96.6% were clonally related to the preceding CLL. MYC translocation (45 pts evaluated) occurred in 17.8%. CK (20 pts evaluated) was found in 70%, with a median number of chr abn of 8 (range 0-20). Of those with CK, 33.3% had a polyploid subclone. With a median follow-up of 17.8 months (range 2.1-83.0) there were 42 deaths, with a median OS of 14.3 months (range 6.9-29.1). For this subset of patients with karyotype data available who would go on to develop RT, an exploratory univariable analysis for OS from RT found that increasing number of chr abn as a continuous variable at CLL dx was associated with worse OS (HR 1.10, 95% CI 1.02-1.19, p=0.01). Similarly, at RT, increasing number of chr abn in CLL tissue (HR 1.09, 95% CI 1.02-1.16, p=0.01) and in RT tissue (HR 1.09, 95% CI 1.01-1.18, p=0.03) was also prognostic of survival. Karyotype evolution in CLL tissue at RT (HR 3.02, 95% CI 1.02-8.94, p=0.05) was borderline significant for worse OS. Conclusions: Our multi-center study identified increasing number of chr abn at CLL diagnosis and at time of RT, and clonal evolution in the CLL tissue, are associated with worse OS in pts with RT whose CLL was treated without CIT. Limitations include incomplete cytogenetics data across the cohort and potential variability across institutions in cytogenetics laboratory practices. This provides further evidence for the clinical utility of chr analysis in the modern era of CLL therapy.

Introduction: Richter transformation is the development of an aggressive lymphoma, most commonly diffuse large B-cell lymphoma, in patients (pts) with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). Transformation into Hodgkin lymphoma (HT) is a rare event and outcomes in pts with this complication in the current CLL/SLL therapeutic era of small molecule inhibitors (SMI; e.g., Bruton tyrosine kinase inhibitors [BTKi] and BCL2 inhibitors [BCL2i]) are unknown. Methods: We conducted a retrospective study of pts from 12 academic centers. Pts with HT who had not previously received chemotherapy for CLL/SLL-directed treatment (tx) were included. Pt, disease, and tx characteristics were collected. HT was categorized into 3 groups: “Concurrent HT,” defined as HT and CLL/SLL diagnosed simultaneously (within 3 months); “HT without prior CLL/SLL tx,” defined as HT and CLL/SLL diagnosed >3 months apart with the CLL/SLL never treated; and “HT with prior non-chemotherapy tx for CLL/SLL” defined as having received non-chemotherapy CLL/SLL-directed tx prior to the diagnosis (dx) of HT. Overall survival (OS) was measured from HT dx and estimated using the Kaplan-Meier method. Cox regression model was used to identify prognostic factors associated with OS. Results: Within a total cohort of 402 pts with Richter transformation (all histologies) without prior chemotherapy, 41 pts with HT (10%) were identified: 12 with concurrent HT, 10 with HT without prior CLL/SLL tx, and 19 with HT with prior non-chemotherapy tx for CLL/SLL. The median age at CLL/SLL dx was 62 years (range 31-96 years) and 73% were male. At CLL/SLL dx, 67% (14/21 evaluated) had unmutated IGHV, and 24% (8/34 evaluated) had TP53 disruption (del(17p) and/or TP53 mutation). The median age at HT dx was 65 years (range 31-96 years) among all pts. At HT dx, there was no significant difference in highest SUV on PET (median 12.3, range 3-31.1), lactate dehydrogenase (LDH) level (median 242 U/L, range 112-859 U/L), or lymph node longest diameter (median 4.6 cm, range 1.6-25 cm) among the 3 subgroups. The median time from CLL/SLL dx to HT dx was 5.4 years (range 0.3-16.5 years) in pts with HT without prior CLL/SLL tx and 4.2 years (range 0.5-17.3 years) in pts with HT with prior non-chemotherapy tx for CLL/SLL. The median number of prior non-chemotherapy CLL/SLL-directed tx was 1 (range 1-6) and included BTKi only (n=17) and BTKi and BCL2i sequentially (n=2); no patient had received only prior BCL2i. Among the 19 pts with HT with prior non-chemotherapy tx for CLL/SLL, 18 pts were on active tx at time of dx (17 BTKi, 1 BCL2i). Initial HT management included: doxorubicin, bleomycin, vinblastine, dacarbazine (ABVD; n=16), brentuximab vedotin (BV)-AVD (n=10), radiation only (n=2), other systemic tx (n=11), and supportive cares / hospice (n=2). All but 1 of the 11 other systemic tx were various HL tx regimens. Across all pts with available data (n=32), the overall response rate to 1st line HT tx was 78% (69% complete response rate); 13% had progressive disease and 9% (n=3; all with concurrent HT) died within 6 months without formal response assessment. A total of 11 pts received at least 1 additional line of therapy for HT, which included BV (n=4), an immune checkpoint inhibitor (n=1), or both (n=6) at any point beyond 1st line HT tx. Median follow-up from HT dx was 32.8 months (range 2.4-253.8 months). The 36-month OS for the entire cohort was 75% (95% CI: 55-87%). The 36-month OS estimates by subgroups were: 62% (95% CI: 26-84%) in pts with concurrent HT, 100% in pts with HT without prior CLL/SLL tx (no events by 36 months), and 67% (95% CI: 33-87%) in pts with HT with prior non-chemotherapy tx for CLL/SLL. Exploratory univariable analysis identified TP53 disruption at CLL dx (HR 12.36; 95% CI: 2.55-59.84) and lymph node longest diameter (HR 1.32 per 1 cm increase; 95% CI: 1.12-1.55) and LDH 2-fold increase (HR 3.97; 95% CI 1.24-12.68) at HT dx as prognostic for worse OS. HT subgroup was not prognostic. Conclusions: This is the largest report of outcomes in pts with CLL/SLL who develop HT following SMI tx without any prior chemotherapy, representing a contemporary cohort. Prior CLL/SLL tx status was not associated with OS; however, cautious interpretation is required given the sample size. Our findings support the use of appropriate HL-directed treatment in the setting of HT; however, OS estimates remain worse than would be expected in an older adult de novo HL cohort (Cheng Blood Adv 2022).

Introduction: Recent efforts have shed light on the clinical and laboratory factors associated with toxicity and response to BCMA-directed CAR-T therapy in patients with relapsed/refractory multiple myeloma (RRMM). However, a major limitation of current scoring systems lies in their assessment at time of lymphodepletion. Because they are not determined before apheresis, they are ill-equipped to guide patient selection, anticipate level-of-care, or plan pre-emptive toxicity management strategies. We therefore aimed to characterize early predictors of CAR-T toxicity and response. Study Design: In this multicenter observational study, we examined demographic, clinical, and laboratory data across three distinct timepoints: indication (e.g., treatment decision), apheresis, and pre-lymphodepletion (LD). CRS and ICANS were graded according to ASTCT criteria. Hematotoxicity (ICAHT) was graded using EHA/EBMT criteria. Early infections (day 0-100) were defined based on microbiologic data or as a clinical infection syndrome, and graded per Hill et al, Blood 2018. Kaplan-Meier estimates of progression-free (PFS) and overall survival (OS) were compared by log-rank test. Cox proportional hazard models were applied to explore associations between pre-apheresis risk factors and key toxicity and survival outcomes. The CAR-HEMATOTOX (HT) score - encompassing markers of inflammation (e.g., CRP, ferritin) and marrow reserve (e.g., hemoglobin, ANC, platelet count) - was determined at each timepoint (Rejeski et al, Blood 2021). Results: We included 530 RRMM patients treated with standard-of-care cilta-cel (n=184) or ide-cel (n=346) across nine centers. Median age was 65 (range 31-88), median ECOG was 1 (IQR 0-1), and patients received a median of 5 prior lines of therapy (IQR 4-7). The median time from indication to apheresis was 16 days (IQR 7-52), while the median time from apheresis to infusion was 56 days (IQR 46-69). The proportion of high-risk patients by HT score did not change between the pre-apheresis and LD timepoints (19% vs. 20%, p=0.82). Most patients stayed either low-risk (n=388, 73.2%) or high-risk (n=68, 12.8%). However, 35 patients (6.6%) shifted from high-to-low risk, while 39 patients (7.4%) progressed from low-to-high risk - reflecting their response to bridging therapies. We noted considerable differences in morbidity and mortality based on the pre-apheresis HT score. Compared to their low-risk counterparts (score 0-2, n=427), high-risk patients (score ≥3, n=103) were hospitalized longer (12 vs. 15 days, p=0.009) and required more frequent ICU admissions (6% vs. 12%, p=0.05). They exhibited more severe early cytopenias (G3+: 8% vs. 25%, p<0.001) and late cytopenias (G3+: 7% vs. 21%, p<0.001), resulting in increased use of TPO agonists and stem cell boosts. Grade 3 or higher ICANS was also more common in HThigh patients (3% vs. 11%, p=0.006), as were severe infections (14% vs. 27%, p=0.007). We found increased non-relapsed mortality in HThigh patients (1-yr NRM 4.6% vs. 16.1%, p<0.001), but no significant difference in the occurrence of secondary malignancies (p>0.9). With a median follow-up of 12.4 months, HThigh patients showed inferior PFS (1-yr PFS 29% vs. 63%, p<0.0001) and OS (1-yr OS 49% vs. 83%, p<0.0001). Transitioning from a low-to-high score was linked to poor survival (1-yr PFS 26%), while the shift from high-to-low risk was associated with favorable outcomes (1-yr PFS 51%). In a multivariable Cox regression model of pre-apheresis features, a high HT score (aHR 2.52, p<0.0001), prior anti-BCMA therapy (aHR 1.55, p=0.04), history of extramedullary disease (aHR 1.42, p=0.02), and penta-refractoriness (aHR 1.45, p=0.02) were independently associated with PFS. Notably, the presence of more than 3 of these high-risk features defined an ultra-high-risk cohort of 28 patients (5.3%) with particularly dismal survival (1-year PFS 15%). Conclusions: Leveraging granular pre-apheresis data from a large international cohort, we identify early markers of toxicity and response in CAR-T-treated RRMM patients. The HT score - reflecting baseline inflammation and hematopoietic reserve - identified high-risk patients likely to benefit from pre-emptive toxicity mitigation strategies such as prophylactic stem cell collection. Most importantly, we characterize a small yet ultra-high-risk group of RRMM patients in need of more effective bridging and therapeutic options.

Background: Although advanced stage cHL typically has excellent disease outcomes, 20-30% of patients (pts) experience treatment failure. In addition, decision-making is challenging given varying treatment options and incomplete prognostic data across the disease course. Pre-treatment factors, such as those incorporated into the Advanced Stage Hodgkin Lymphoma International Prognostication Index (A-HIPI), predict 5 year (y) overall survival (OS) and progression-free survival (PFS) (Rodday JCO 2023). Other than interim PET (iPET) results, it is unknown what factors influence cHL disease states mid-therapy. Using multistate modeling (MSM) and individual pt data from the HoLISTIC Consortium, we refined prognostication across the cHL disease course, specifically assessing the relationships between A-HIPI, iPET and end of treatment (EOT) response, and whether the A-HIPI and iPET provide independent prognostic information. Methods: We analyzed 1240 pts aged 18-65y with newly diagnosed Stage IIB, III or IV cHL treated on 2 advanced stage PET-adapted trials (RATHL, SWOG0816). All pts first received 2 cycles of ABVD; those with a negative iPET (Deauville score (DS) ≤3) received ABVD or AVD, and those with a positive iPET (DS >3) received BEACOPP. In contrast to other methods, MSMs incorporate multiple disease states into one model, account for censoring and competing risks, and estimate transitions between disease states using different covariates. Our MSM had 6 states: diagnosis, negative iPET, positive iPET, EOT non-progression (e.g., DS ≤ 3), treatment failure, and death. Treatment failure included progression or relapse. All pts start at the diagnosis state and can transition to other states without return to prior states. Transition states with <5 events were excluded. The MSM was estimated using a multivariable Cox model with censoring at 5y. Covariates were the 5y PFS A-HIPI (comprised of stage and continuous age, lymphocyte count and albumin), which was included for all transitions, and iPET, which was included for transitions from EOT non-progression and from treatment failure. Higher scores on the 5y PFS A-HIPI indicate lower risk of progression or death; the A-HIPI was modeled for a 1 standard deviation (SD) increase. We calculated probabilities of 5y treatment failure for 4 sample pts based on low (70) and high (85) A-HIPI scores, positive and negative iPET, and EOT non-progression. Results: Median age was 33y (Q1=25, Q3=45), 56% were male, 23% were stage IIB, 40% III and 37% IV, and mean A-HIPI was 77 (SD=7). Median follow-up was 75 months (Q1=53, Q3=92). At iPET, 80% (95% CI 78%, 83%) were negative and 16% (95% CI 14%, 18%) were positive. At EOT, 90% (95% CI 89%, 92%) were in the non-progression state. At 5y, 75% (95% CI 73%, 78%) were in the non-progression state, 16% (95% CI 14%, 19%) had experienced treatment failure, and 9% (7%, 11%) had died. Better A-HIPI scores (per SD) were associated with lower rates of transitioning from diagnosis to positive iPET (HR=0.80, p<0.01) and from positive iPET to treatment failure (HR=0.58, p=0.04). Better A-HIPI scores (per SD) were also associated with lower rates of transitioning from EOT non-progression to treatment failure (HR=0.78, p<0.01) and from treatment failure to death (HR=0.64, p<0.01), adjusting for iPET. Positive iPET was associated with an increased rate of transitioning from EOT non-progression to treatment failure (HR=1.90, p<0.01), adjusting for A-HIPI. The probability of 5y treatment failure for 4 sample pts was: 25% for low A-HIPI and positive iPET; 20% for high A-HIPI and positive iPET; 13% for low A-HIPI and negative iPET; and 12% for high A-HIPI and negative iPET. Conclusions: We created a novel MSM that refines prognostication across the cHL disease course by incorporating pre- and post-treatment factors (e.g., iPET) to estimate transitions to future disease states. Although the A-HIPI was developed using pre-treatment factors to predict 5y OS and PFS, we found that it was also associated with transitions to interim disease states, including iPET and EOT response. The A-HIPI and iPET each provided independent prognostic information, supporting the use of both in estimating cHL outcomes. Future analyses will develop clinical prediction models using MSMs that also incorporate varying frontline and salvage treatments and treatment-specific late effects, with the goal of providing individualized information across the disease course.