Afamitresgene autoleucel for advanced synovial sarcoma and myxoid round cell liposarcoma (SPEARHEAD-1): an international, open-label, phase 2 trial

BACKGROUND

Afamitresgene autoleucel (afami-cel) showed acceptable safety and promising efficacy in a phase 1 trial (NCT03132922). The aim of this study was to further evaluate the efficacy of afami-cel for the treatment of patients with HLA-A*02 and MAGE-A4-expressing advanced synovial sarcoma or myxoid round cell liposarcoma.

METHODS

SPEARHEAD-1 was an open-label, non-randomised, phase 2 trial done across 23 sites in Canada, the USA, and Europe. The trial included three cohorts, of which the main investigational cohort (cohort 1) is reported here. Cohort 1 included patients with HLA-A*02, aged 16-75 years, with metastatic or unresectable synovial sarcoma or myxoid round cell liposarcoma (confirmed by cytogenetics) expressing MAGE-A4, and who had received at least one previous line of anthracycline-containing or ifosfamide-containing chemotherapy. Patients received a single intravenous dose of afami-cel (transduced dose range 1·0 × 109-10·0 × 109 T cells) after lymphodepletion. The primary endpoint was overall response rate in cohort 1, assessed by a masked independent review committee using Response Evaluation Criteria in Solid Tumours (version 1.1) in the modified intention-to-treat population (all patients who received afami-cel). Adverse events, including those of special interest (cytokine release syndrome, prolonged cytopenia, and neurotoxicity), were monitored and are reported for the modified intention-to-treat population. This trial is registered at ClinicalTrials.gov, NCT04044768; recruitment is closed and follow-up is ongoing for cohorts 1 and 2, and recruitment is open for cohort 3.

FINDINGS

Between Dec 17, 2019, and July 27, 2021, 52 patients with cytogenetically confirmed synovial sarcoma (n=44) and myxoid round cell liposarcoma (n=8) were enrolled and received afami-cel in cohort 1. Patients were heavily pre-treated (median three [IQR two to four] previous lines of systemic therapy). Median follow-up time was 32·6 months (IQR 29·4-36·1). Overall response rate was 37% (19 of 52; 95% CI 24-51) overall, 39% (17 of 44; 24-55) for patients with synovial sarcoma, and 25% (two of eight; 3-65) for patients with myxoid round cell liposarcoma. Cytokine release syndrome occurred in 37 (71%) of 52 of patients (one grade 3 event). Cytopenias were the most common grade 3 or worse adverse events (lymphopenia in 50 [96%], neutropenia 44 [85%], leukopenia 42 [81%] of 52 patients). No treatment-related deaths occurred.

INTERPRETATION

Afami-cel treatment resulted in durable responses in heavily pre-treated patients with HLA-A*02 and MAGE-A4-expressing synovial sarcoma. This study shows that T-cell receptor therapy can be used to effectively target solid tumours and provides rationale to expand this approach to other solid malignancies.

FUNDING

Adaptimmune.

A Case of Mediastinal Carcinosarcoma With Beta-HCG Production and KRAS Mutation

Carcinosarcomas of mediastinum are rare and only few well-documented cases are available in the literature. We report a detailed description of mediastinal carcinosarcoma with unique clinical manifestations and immunohistochemical and molecular profiles. A 44-year-old female with an enlarging anterior mediastinal mass was found to have a positive pregnancy test. Thoracoscopic biopsy revealed that the mass represented a carcinosarcoma with adenocarcinoma and chondrosarcoma components. The tumor focally expressed beta-HCG by immunohistochemistry and had KRAS G12A missense mutation by next generation sequencing. The case documents a rare presentation of carcinosarcoma within the mediastinum with uncommon paraneoplastic syndrome and genetic profile. Awareness of these unusual clinical and pathological manifestations of the tumor will help in reaching correct diagnosis and proper management of such patients.

Adjuvant Palbociclib May be Associated with Delayed Recurrence in Completely Resected Retroperitoneal Liposarcoma: Results of a Single-Institution Retrospective Cohort Study

BACKGROUND

Retroperitoneal liposarcomas are locally aggressive and frequently recur following complete surgical resection. Palbociclib, a cyclin-dependent kinase (CDK) 4/CDK6 inhibitor, is effective in the treatment of metastatic or unresectable liposarcoma.

OBJECTIVE

The purpose of this study was to describe our initial experience using adjuvant palbociclib to delay recurrence.

METHODS

Patients with resected RPS were identified from a prospectively maintained institutional database. In 2017, we began offering adjuvant palbociclib to patients following complete gross resection. Treatment interval, defined as the time between surgical resection and re-resection or change in systemic therapy, was compared between patients selected for adjuvant palbociclib or observation.

RESULTS

Between 2017 and 2020, 12 patients underwent a total of 14 operations (14 patient cases) and were selected for adjuvant palbociclib for recurrence prevention. These patients were compared with 14 patients who, since 2010, underwent a total of 20 operations (20 patient cases) and were selected for observation. Histology was primarily dedifferentiated liposarcoma for both groups (observation: 70% [14/20]; adjuvant palbociclib: 64% [9/14]). All patients underwent complete gross resection. Neither age, number of previous surgeries, histologic grade, or Eastern Cooperative Oncology Group (ECOG) performance status differed between groups (p > 0.05 for all). Patients selected for adjuvant palbociclib experienced a longer treatment interval than those selected for observation, although it did not reach statistical significance (20.5 months vs. 13.1 months, p = 0.08, log rank).

CONCLUSION

Adjuvant palbociclib may be associated with a prolonged interval between liposarcoma resection and the need for re-resection or other systemic therapy. Palbociclib may be effective in delaying liposarcoma recurrence, and its use for this indication warrants prospective study.

Sorafenib-Induced Capillary Leak Syndrome

Capillary leak syndrome is a rare life-threatening disorder of acute endothelial hyperpermeability. It consists of initial fluid extravasation resulting in hypotension, hypoalbuminemia, and hemoconcentration, followed by noncardiogenic pulmonary edema from rapid fluid remobilization into intravascular compartment. Drug-induced etiology is an important diagnostic consideration in cancer patients, particularly with use of antimetabolites, immunostimulants, and monoclonal antibodies. Sorafenib-mediated capillary leak syndrome has never been reported. Here, we present the case of a 29-year-old female patient with a desmoid tumor of the thigh, who was admitted for acute hypoxic respiratory failure after recent initiation of sorafenib. She was found to have extensive pulmonary edema, bilateral pleural effusions, and hemoconcentration, all of which stabilized on supportive care with noninvasive mechanical ventilation and intravenous diuresis. Her infectious and cardiac work-up were negative. Given the temporal relationship between sorafenib use and symptom onset as well as a lack of an alternative etiology of her findings, patient was deemed to have sorafenib-induced acute capillary leak syndrome. Importantly, she did not become hypotensive prior to or during this hospitalization. To our knowledge, we reported for the first time an atypical presentation of acute capillary leak syndrome due to sorafenib use without hemodynamic instability.

Autologous T cell therapy for MAGE-A4+ solid cancers in HLA-A*02+ patients: a phase 1 trial

Affinity-optimized T cell receptors can enhance the potency of adoptive T cell therapy. Afamitresgene autoleucel (afami-cel) is a human leukocyte antigen-restricted autologous T cell therapy targeting melanoma-associated antigen A4 (MAGE-A4), a cancer/testis antigen expressed at varying levels in multiple solid tumors. We conducted a multicenter, dose-escalation, phase 1 trial in patients with relapsed/refractory metastatic solid tumors expressing MAGE-A4, including synovial sarcoma (SS), ovarian cancer and head and neck cancer ( NCT03132922 ). The primary endpoint was safety, and the secondary efficacy endpoints included overall response rate (ORR) and duration of response. All patients (N = 38, nine tumor types) experienced Grade ≥3 hematologic toxicities; 55% of patients (90% Grade ≤2) experienced cytokine release syndrome. ORR (all partial response) was 24% (9/38), 7/16 (44%) for SS and 2/22 (9%) for all other cancers. Median duration of response was 25.6 weeks (95% confidence interval (CI): 12.286, not reached) and 28.1 weeks (95% CI: 12.286, not reached) overall and for SS, respectively. Exploratory analyses showed that afami-cel infiltrates tumors, has an interferon-γ-driven mechanism of action and triggers adaptive immune responses. In addition, afami-cel has an acceptable benefit-risk profile, with early and durable responses, especially in patients with metastatic SS. Although the small trial size limits conclusions that can be drawn, the results warrant further testing in larger studies.

Results of a phase I dose escalation and expansion study of tegavivint (BC2059), a first-in-class TBL1 inhibitor for patients with progressive, unresectable desmoid tumor

11523

Background: Desmoid tumors are known to have increased nuclear β-catenin levels. Tegavivint selectively disrupts the interaction of β-catenin and TBL1/ TBLR1, resulting in specific degradation of nuclear β-catenin. The primary objectives of this study were to determine the maximum tolerated dose (MTD), safety, and preliminary efficacy of tegavivint in patients (pts) with desmoid tumors. Methods: This study ( NCT03459469) utilized an accelerated dose escalation schema for the first two dose levels followed by a 3+3 design to determine the MTD/recommended phase 2 dose (RP2D) of tegavivint, followed by a dose expansion phase. The study included adult pts with sporadic desmoid tumors that were progressive (20% increase in tumor volume, recurrent in one year from surgery, or symptomatic), unresectable, and measurable via WHO criteria. Tegavivint was administered IV weekly (three weeks on, one week off) up to two years. Results: 24 pts were enrolled. Dose escalation enrolled 17 pts in six dose levels from 0.5 - 5 mg/kg. In dose expansion, 7 additional pts were enrolled. Dose expansion cohort also included 6 pts in dose escalation that were escalated to RP2D and 3 pts treated at RP2D in dose escalation (n = 16 total). Median age was 43 years (18-66). Median time from diagnosis was 3.1 years with median of one prior systemic treatment (range 0-6). Median time on study was 9.4 months; 3 pts remain on study at data cut-off. No dose-limiting toxicities were observed; MTD was not determined. RP2D was declared at 5 mg/kg based on pharmacologically relevant plasma concentrations and preliminary efficacy. Trough plasma concentrations (Cmin) exceeded in vitro IC50 efficacy estimates at 4 mg/kg and 5 mg/kg. Median half-life was 38 hours supporting once weekly administration. Treatment-related adverse events (TRAEs) occurring in ≥20% of pts included fatigue (71%), headache (38%), nausea (33%), constipation (21%), decreased appetite (21%), and dysgeusia (21%), mostly Grade 1-2. Grade 3 TRAEs of hypophosphatemia, stomatitis, increased ALT, diarrhea, and headache occurred in 5 separate pts. There were no grade 4-5 adverse events (AEs). One serious AE of Grade 2 extravasation occurred. Objective response rate (ORR) of 17% across all dose levels and 25% at RP2D (WHO and RECIST criteria) were observed. Median duration of response was 8.1 months (range 6 to 11.8 months) with all responses ongoing. The 9-month progression free survival rate was 76% (95% CI: 54 - 90%) among all pts and 79% (95% CI: 51 – 93%) among those treated at RP2D. Patient reported outcomes and correlative science will be included in the presentation. Conclusions: Tegavivint is well tolerated with mostly Grade 1/2 AEs and no serious toxicity associated with WNT inhibition. The ORR of 25% at the RP2D warrants continued development of tegavivint in desmoid tumors. Clinical trial information: NCT03459469.

Clinical markers of immunotherapy outcomes in sarcoma

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Background: Despite immunotherapy’s promise in oncology, its use for sarcoma remains challenging. There are no sarcoma-specific biomarkers for immune checkpoint inhibitors (ICI). Previously, we reported our institutional experience highlighting ICI activity in 29 patients with sarcoma. In this updated study, we further explore responses to ICI based on ICI regimen and other covariates to identify significant clinical factors in sarcoma outcomes. Methods: Patients in the Ohio State University Sarcoma clinics were enrolled in the Sarcoma Retrospective ICI database from January 1, 2015 through November 1, 2021. Data included treatment regimen (single agent ICI or ICI+combination) along with covariates: stage, age, gender, histology, change in neutrophil-to-lymphocyte ratio (NLR), number of cycles of ICI and immune-related adverse events (irAE). ICI+combination was further categorized into ICI+chemotherapy, ICI+radiation, ICI+surgery or ICI+multiple (more than 2 modalities). Statistical analysis included log rank tests and proportional hazard regression. The primary objective was to evaluate overall survival (OS) and progression-free survival (PFS). Results: One hundred and thirty-five patients met inclusion criteria. We demonstrated improved OS in patients treated with ICI+combination (p = 0.014, median 64 weeks), but no effect on PFS (p = 0.471, median 31 weeks). Whether patients had received single agent or combination ICI, those who received more than 3 cycles of ICI had an improved OS and PFS (p < 0.05 for both). Patients who received single-agent ICI and whose change in NLR was less than 5 had an improved OS (p = 0.002); this was not seen in patients who received ICI+combination therapy (p = 0.441). Patients who had a documented irAE of dermatitis had improved OS but only in the ICI+combination cohort (p = 0.021). There were no differences in OS based on age, gender, histology or sub-categories of ICI+combination. This was not the case for PFS; patients who received any ICI regimen and were younger than 70 had a worse PFS (p = 0.036). Patients who developed an irAE, specifically colitis (p = 0.009), hepatitis (p = 0.048) and dermatitis (p = 0.003) had an improved PFS. There were no differences in PFS based on ICI regimen (or sub-categories of ICI+combination), gender, histology, change in NLR or grade of irAE. Our ICI cohort results are consistent with historical data from our previous study. Further, irAEs are similar to historical data. Conclusions: This retrospective study demonstrates that ICI+combination therapy can improve OS in sarcoma. This is consistent with our prior results of ICI in sarcoma. Benefits in OS/PFS were seen in patients who received more than 3 cycles of ICI and developed certain irAE. These results can direct the optimal duration of ICI therapy. Those with decreased change in NLR also had improved OS, demonstrating a potential prognostic biomarker. Further studies are needed to validate our findings.

Primary efficacy and safety of letetresgene autoleucel (lete-cel; GSK3377794) pilot study in patients with advanced and metastatic myxoid/round cell liposarcoma (MRCLS)

11500

Background: Lete-cel is an autologous T-cell therapy targeting NY-ESO-1 tumors using a genetically modified, high-affinity T-cell receptor. MRCLS is a sarcoma with poor response to current immunotherapy approaches and limited treatment options. The cancer testis antigen NY-ESO-1 is expressed in 80‒90% of MRCLS tumors, making this a promising target. This report summaries the primary efficacy and safety results of a pilot study of lete-cel in patients (pts) with advanced or metastatic MRCLS. Methods: This is an open label, study of lete-cel in pts with advanced or metastatic MRCLS following reduced-dose (Cohort 1 [C1]; 30 mg/m2 fludarabine [flu] x 3d + 600 mg/m2 cyclophosphamide [cy] x 3d) or standard dose (Cohort 2 [C2]; 30 mg/m2 flu x 4d + 900 mg/m2 cy x 3d) lymphodepletion (LD). Key eligibility criteria were: age ≥18 y; HLA-A*02:01; A*02:05, or A*02:06; advanced or metastatic NY-ESO-1+ MRCLS (≥30% of cells 2+/3+ by IHC); prior anthracycline treatment, and measurable disease. The transduced T cell dose range was 1– 8 × 109. Response was assessed at weeks 4, 8, 12, 24, then every 3 months (mo) until disease progression, death, or withdrawal. Investigator-assessed (IA) ORR by RECIST v1.1 was the primary efficacy endpoint. Secondary endpoints included safety, independently assessed ORR by RECIST v1.1, time to response (TTR), duration of response (DOR), progression-free survival (PFS). Overall survival (OS) was an exploratory endpoint. Results: 23 pts enrolled from March 2017 to February 2020. The median age was 47.0 yrs (range 33 to 72). 20 pts were dosed with T cells, 10 in each cohort with a median transduced T cell dose of 4.6 x 109. 8 of 20 pts (40%) had 1 line of prior therapy, 6 pts (30%) had 2 lines, and 6 pts (30%) had ≥3 lines. The median follow-up was 5.6 (C1) and 12.9 (C2) mo. In C1 the IA ORR was 20%, with best response (BR) of partial response (PR) in 2 pts and BR of stable disease (SD) in 8 pts. The median TTR was 1.9 mo, median DOR was 5.3 mo (95% CI: 1.9-8.7), and median PFS was 5.4 mo (95% CI: 2.0-11.5). In C2 the IA ORR was 40%, with BR of PR in 4 pts and BR of SD in 5 pts. The median TTR was 1.9 mo, median DOR was 7.5 mo (95% CI: 6.0-NE), and median PFS was 8.7mo (95% CI: 0.9-NE). OS is not yet mature. All pts experienced at least 1 treatment-emergent adverse event (TEAE). 55% of pts experienced serious TEAEs. 90% of pts had Gr ≥3 TE neutropenia, with 83% probability of resolution of initial Gr ≥3 occurrence by Day 30. Cytokine release syndrome occurred in 80% of pts, of which 25% were Gr 3, with 1st onset within 5d of infusion and median duration 7.5d. No Graft-vs-host disease, immune effector cell–associated neurotoxicity syndrome, Guillain-Barré Syndrome were reported. Conclusions: Treatment with a single dose of lete-cel showed anti-tumor activity, including response and long median PFS with an acceptable safety profile in pts with advanced and metastatic MRCLS. Clinical trial information: NCT02992743.

Randomized Prospective Trial Exploring the Impact of Structured Journaling in Patients With Sarcoma on the Management of Treatment-Related Adverse Events

Treatment-related adverse events associated with systemic anticancer therapy (SACT) can deter patients with sarcoma from completing treatment. With self-monitoring, patients may be better empowered to self-advocate for improved symptom management. We hypothesized that by incorporating journaling, a structured form of self-monitoring, care team communication, and symptom management would improve. We thus designed a prospective randomized trial exploring journaling as a therapeutic adjuvant for symptom management (NCT03258892).

Master protocol to assess safety and recommended phase 2 dose of next generation NY-ESO-1–specific TCR T-cells in HLA-A*02 patients with synovial sarcoma or non-small cell lung cancer (Substudies 1 and 2)

TPS2661

Background: Letetresgene autoleucel (lete-cel; GSK3377794) is an autologous T-cell therapy using a genetically modified T-cell receptor (TCR) to improve recognition of cancer cells expressing NY-ESO-1/LAGE-1a. Next generation NY-ESO-1 TCR T-cell therapies, such as GSK3901961 and GSK3845097, integrate added genetic modifications to enhance anticancer activity. GSK3901961 co-expresses the CD8α chain to stabilize TCR-human leukocyte A (HLA) class I interactions on CD4+ T cells, improving T-cell persistence and helper functions such as Type 1 T-helper antitumor responses. GSK3845097 co-expresses a dominant negative transforming growth factor-β (TGF-β) type II receptor to reduce TGF-β pathway activation and maintain T-cell proliferation, cytokine production, and cytotoxicity in the tumor microenvironment. A first-time-in-human master protocol (NCT04526509) will evaluate safety, tolerability, and recommended phase 2 dose (RP2D) of these and possible subsequent therapies. Substudy 1 will assess GSK3901961 in patients (pts) with advanced non-small cell lung cancer (NSCLC) or synovial sarcoma (SS). Substudy 2 will assess GSK3845097 in pts with advanced SS. Methods: Each substudy includes a dose confirmation stage to assess RP2D and a dose expansion stage. Key inclusion criteria are age ≥18 y; measurable disease per RECIST v1.1; HLA-A*02:01, A*02:05, or A*02:06 positivity; NY-ESO-1/LAGE-1a tumor expression; advanced (metastatic/unresectable) SS with t(X;18) translocation and anthracycline-based therapy receipt/completion/intolerance (SS only); and Stage IV NSCLC, receipt of ≥1 prior line(s) of standard of care (SOC) therapy including programmed death receptor- or ligand-1 inhibitors, and SOC chemotherapy receipt/intolerance (Substudy 1 only). Key exclusion criteria are prior malignancy that is not in complete remission or clinically significant systemic illness; prior receipt of gene/NY-ESO-1–specific therapy or allogenic stem cell/solid organ transplant; central nervous system metastases (SS only); and actionable genetic aberration and receipt/failure of ≥3 systemic therapy lines (Substudy 1 only). Primary endpoints are safety (adverse events) and tolerability (dose-limiting toxicities). Secondary endpoints include investigator-assessed overall response rate, duration of response, and maximum expansion/persistence and phenotype of infiltrating transduced T cells. Exploratory endpoints include laboratory parameters, overall survival, and anti-GSK3901961 or -GSK3845097 titers as applicable. Analyses will be descriptive. The substudies are enrolling. Funding: GSK (209012; NCT04526509). Editorial support was provided by Eithne Maguire, PhD, of Fishawack Indicia, part of Fishawack Health; funded by GSK. Previously presented at AACR 2021 (CT219). Clinical trial information: NCT04526509.

Safety and efficacy of letetresgene autoleucel (lete-cel; GSK3377794) in advanced myxoid/round cell liposarcoma (MRCLS) following high lymphodepletion (Cohort 2): Interim analysis

11521

Background: Cancer testis antigen NY-ESO-1 is expressed in multiple tumor types, including 80‒90% of MRCLS [1,2]. Overall response rates (ORRs) to MRCLS treatment are low (1L, <20%; 2L, <10%) [2]. Lete-cel, an autologous T-cell therapy, targets NY-ESO-1/LAGE-1a+ tumors using a genetically modified, high-affinity T-cell receptor. High-dose lymphodepletion (LD) was linked with better responses in synovial sarcoma [3]; the current study tested this hypothesis in MRCLS. Methods: This open label, pilot study evaluates lete-cel efficacy and safety in advanced MRCLS following low-dose (Cohort 1 [C1]; 30 mg/m2 fludarabine [flu] x 3d + 600 mg/m2 cyclophosphamide [cy] x 3d) or high-dose (Cohort 2 [C2]; 30 mg/m2 flu x 4d + 900 mg/m2 cy x 3d; initiated based on C1 data) LD. Key eligibility: age ≥18 y; HLA-A*02:01; A*02:05, or A*02:06; advanced high-grade NY-ESO-1+ MRCLS (≥30% of cells 2+/3+ by IHC); prior anthracycline; measurable disease; specified washouts; and active/chronic/intercurrent illness restrictions. Stages include screening, leukapheresis, lete-cel manufacture, LD, lete-cel infusion (1– 8 × 109 transduced T cells), follow-up. Response is assessed at wk 4, 8, 12, and 24, then every 3 mo to disease progression/death/withdrawal. The primary efficacy endpoint is investigator-assessed ORR by RECIST v1.1. In C1 (n=10 patients [pts]), lete-cel was well tolerated and linked with 2 confirmed partial responses (PR; ORR, 20%) and stable disease (SD) in 8 pts. Planned interim analysis for C2, shown here, was done once all 10 treated pts had ≥3 post-baseline disease assessments or progressed/died/withdrew. Efficacy data will be correlated with transduced cell kinetics and pharmacodynamics marker profiles. Results: Durable (1.0–7.8 mo) PR (4/10 pts [ORR, 40%]; 2 ongoing) and prolonged (2.7–10.6 mo) SD (5/10 pts; 3 ongoing) with tumor regression were observed. Treatment-emergent cytopenias occurred in all pts. All experienced T-cell related cytokine release syndrome (5 serious adverse events; 30% Grade 3), with onset ≤5d of infusion and median duration 7.5d. Graft-vs-host disease, immune effector cell–associated neurotoxicity syndrome, pancytopenia, or aplastic anemia were not reported. Conclusions: A single lete-cel infusion after high LD showed antitumor activity in advanced MRCLS and a manageable safety profile consistent with other lete-cel studies. The trial is active but no longer recruiting (NCT02992743). MRCLS is included in a separate, ongoing lete-cel study (NCT03967223). References: 1. D’Angelo SP, et al. J Clin Oncol 2018;36:15_suppl, 3005. 2. Pollack SM, et al. Cancer Med 2020;9(13):4593–602. 3. D’Angelo SP, et al. J Immunother Cancer 2020;8:P298. Funding: GSK (208469; NCT02992743). Editorial support was provided by Eithne Maguire, PhD, of Fishawack Indicia, part of Fishawack Health, and funded by GSK. Clinical trial information: NCT02992743.

The sarcoma microbiome as a diagnostic and therapeutic target

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Background: Sarcoma is a heterogeneous group of malignant tumors that consist of distinct histological and molecular subtypes, each with unique features. Despite immunotherapy’s promise in many cancers, immunotherapeutic approaches for sarcoma have had variable response rates. Evaluating the tumor microbiome is a promising new approach that aims to improve our understanding of the immunogenicity of sarcoma subtypes, leading to improved treatment options and better clinical outcomes. Methods: We utilized The Cancer Genome Atlas (TCGA) and Genome Tissue Expression (GTEx) database to obtain RNA sequencing (RNAseq) data to identify microbes in sarcoma samples (all subtypes available). Due to the large number of sarcoma subtypes, we focused on three groups: dedifferentiated liposarcoma (DDLPS), leiomyosarcoma (LMS) and “other,” representing all other sarcoma subtypes. We utilized ExoTIC, “Exogenous sequences in Tumors and Immune cells,” a tool recently developed by Dr. Daniel Spakowicz and Dr. Xaiokui Mo. ExoTIC takes raw RNAseq reads and carefully aligns to both human and non-human reference genomes to identify low-abundance microbes. Models of association were analyzed based on each of the three groups as well as all the samples: “All” group. We performed Cox proportional hazards regression to identify the microbes associated with overall survival (OS). Results: We evaluated 97 LMS, 56 DDLPS and 100 “other” RNAseq samples (Table). ExoTIC identified 1304 microbes, of which 431 were statistically associated with OS in the “All” group. Of these, 50 microbes were statistically associated only with DDLPS, 54 only with LMS (e.g., Candida dubliniensis, Mycobacterium avium, Streptococcus sp. Z15), and 46 with “other.” The presence of no organism was associated with improved survival. Median hazard ratios were largest in DDLPS (2.3), followed by “other” (2.1) and LMS (1.9). Only 18 microbes were found in the DDLPS, LMS and “All” groups, including Bacillus sp., Streptococcus lutetiensis, Clostridium tetani, and Pseudomonas sp. LTJR-52. Each was negatively correlated with survival with a median hazard ratio of 2.5. Conclusions: We found a specific relationship between microbial presence and histological sarcoma subtype (DDLPS, LMS), which also statistically correlated with OS. Assessing individual characteristics of a sarcoma histological subtype with its particular microenvironment (e.g., microbes) can lead to personalized treatment insights and improvements in outcomes. Our future research will consist of validating and correlation of the microbial profile of sarcoma subtypes with clinical outcomes retrospectively and prospectively. [Table: see text]

A case of multiple synchronously diagnosed brain metastases from alveolar soft part sarcoma without concurrent lung involvement

Background:

Alveolar soft part sarcoma (ASPS) is a rare soft-tissue sarcoma with a propensity for early hematogenous dissemination to the lungs and frequent brain metastasis. The development of lung metastasis almost invariably precedes intracranial involvement. There are no previously reported cases in which a patient was synchronously diagnosed with ASPS and multiple brain metastasis without lung involvement.

Case Description:

A 29-year-old gentleman was found to have three intracranial lesions following the onset of generalized seizures. Staging studies identified a soft-tissue mass in the left thigh and an adjacent femoral lesion. Biopsy of the soft-tissue mass was consistent with ASPS. The patient then underwent neoadjuvant stereotactic radiotherapy to all three brain lesions, followed by en bloc resection of the dominant lesion. The patient was then started on a programmed death-ligand 1 (PD-L1) inhibitor. Subsequent surgical resection of the primary lesion and femur metastasis demonstrates a histopathologic complete response of the bony metastasis and partial response of the primary lesion. At present, the patient has received 14 cycles of atezolizumab without recurrence of the primary or bony lesions and the irradiated intracranial disease has remained stable without recurrence of the resected dominant lesion.

Conclusion:

While intracranial involvement is relatively common in ASPS, a case with multiple, synchronously diagnosed brain metastasis without concurrent lung metastasis has not been described. The presented case discusses the safety and efficacy of aggressive management of intracranial disease in the setting of atezolizumab. Prospective evaluation of the efficacy of checkpoint inhibitors and the prognostic value of PD-L1 expression in ASPS with brain metastasis are necessary.

A Randomized, Double-Blind, Placebo-Controlled, Phase II Study of Regorafenib Versus Placebo in Advanced/Metastatic, Treatment-Refractory Liposarcoma: Results from the SARC024 Study

LESSONS LEARNED

The results from the liposarcoma cohort of SARC024 confirm previously published data and do not support the routine use of regorafenib in this patient population. Continued exploration of novel therapies, including combination approaches, is warranted for a patient population in whom limited treatment options exist.

BACKGROUND

Regorafenib is a multitargeted kinase inhibitor with a kinase profile overlapping, but distinct from, pazopanib, an agent approved for recurrent and metastatic non-gastrointestinal stromal tumor (GIST), non-adipocytic soft tissue sarcoma. We conducted a randomized, phase II study of regorafenib versus placebo in refractory liposarcoma patients.

METHODS

Patients with advanced or metastatic, treatment-refractory liposarcoma were randomized 1:1 to receive regorafenib 160 mg or placebo once daily (3 weeks on, 1 week off). Patients with well-differentiated liposarcoma only were excluded. Crossover for placebo was allowed upon progression. The primary endpoint was progression-free survival (PFS), according to RECIST version 1.1.

RESULTS

Forty-eight subjects with liposarcoma (34 dedifferentiated, 12 myxoid/round cell, 2 pleomorphic) were enrolled. Median PFS was 1.87 (95% confidence interval [CI], 0.92-3.67) months for regorafenib versus 2.07 (95% CI, 1.64-3.44) months for placebo; stratified hazard ratio [HR], 0.85 (95% CI, 0.46, 1.58), p = .62. No responses were seen on regorafenib. One PR was observed on placebo. Median overall survival was 6.46 (95% CI, 4.16-23.48) months for regorafenib and 4.89 (95% CI, 3.02-9.77) months for placebo, stratified HR, 0.66 (95% CI, 0.31-1.40), p = .28). Treatment-related adverse events were similar to the known safety profile of regorafenib.

CONCLUSION

Regorafenib did not appear to improve PFS in treatment-refractory liposarcoma. No new significant safety signals were observed.

Identifying Opportunities and Challenges for Patients With Sarcoma as a Result of Comprehensive Genomic Profiling of Sarcoma Specimens

PURPOSE

Comprehensive genomic profiling (CGP) of sarcomas is rapidly being integrated into routine clinical care to help refine diagnosis and prognosis and determine treatment. However, little is known about barriers to successful CGP or its clinical utility in sarcoma. We set out to determine whether CGP alters physician treatment decision-making, and whether sarcoma subtypes influence the frequency of successful technical performance of CGP.

METHODS

A single-institution study evaluated profiling outcomes of 392 samples from patients with sarcoma, using a commercially available CGP panel. Of this group, 34 patients were evaluated prospectively (Decision Impact Trial) to evaluate the utility of CGP in physician decision-making. All cases were retrospectively analyzed to identify causes of CGP failure.

RESULTS

CGP successfully interrogated 75.3% (n = 295 of 392) of patients with sarcoma. Bone sarcomas had lower passing rates at 65.3% (n = 32 of 49) compared with soft tissue sarcomas at 76.7% (n = 263 of 343; P = .0008). Biopsy location also correlated with profiling efficiency. Bone biopsy specimens had a 52.8% (n = 19 of 36) passing rate versus lung (61.1%; n = 33 of 54) and abdomen (80.1%; n = 109 of 136) specimens. CGP altered physician treatment selection in 25% of evaluable patients (n = 7 of 28) and was associated with improved progression-free survival.

CONCLUSION

To our knowledge, this is the largest technical evaluation of the performance of CGP in sarcoma. CGP was effectively performed in the vast majority of sarcoma samples and altered physician treatment selection. Tumor location and tissue subtype were key determinants of profiling success and associated with preanalytic variables that affect DNA and RNA quality. These results support standardized biopsy collection protocols to improve profiling outcomes.

Activity of PD1 inhibitor therapy in advanced sarcoma: a single-center retrospective analysis

BACKGROUND

Sarcomas constitute a heterogeneous group of tumors with different clinical behaviors and variable responses to systemic therapies. Recent immunotherapy studies with PD1 inhibitors (PD1i) show promising results with use in certain soft-tissue sarcomas; however, the clinical and molecular features that best predict response to PD1i remain unclear.

METHODS

Demographic, imaging, histologic, and genetic sequencing data was collected for sarcoma patients who received nivolumab or pembrolizumab (PD1i) treatment at our institution between January 1st 2015 and April 23rd 2018. The primary objective was to determine progression-free survival (PFS) in patients with advanced sarcomas receiving PD1i. Secondary objectives included determining overall survival (OS) and assessment of characteristics associated with response to PD1i. Fifty-six patients who were treated with PD1i therapy met inclusion criteria for this study.

RESULTS

Partial response towards PD1i treatment was seen in 3 in 26 evaluable patients, but no complete responses were observed (overall response rate 11.5%). Within this group of patients, the 90 day PFS was found to be 48.8%. In patients in whom PD1 expression was known, there was a statistically significant positive correlation between expression of PD1 and longer PFS and OS rates. Patients that were treated with more than four cycles of PD1i therapy were also more likely to have a greater OS.

CONCLUSIONS

This study suggests activity of PD1i in a pretreated cohort of advanced sarcoma patients, particularly for the subset of patients with PD1 positive tumors. Our results highlight the importance of further research to better target the optimal patient population and markers of response.

Phase I dose escalation and expansion trial to assess the safety and efficacy of ADP-A2M4 SPEAR T cells in advanced solid tumors

102

Background: MAGE-A4 is a cancer/testis antigen with expression in many solid tumors promoting cell growth by preventing cell cycle arrest and apoptosis. This study (NCT03132922) evaluated safety and efficacy of SPEAR T-cells directed against the MAGE-A4 peptide expressed in 9 tumor types. Methods: This Phase I dose-escalation, expansion trial evaluated patients (pt) who were HLA-A*02 positive with advanced cancers that expressed the MAGE-A4 protein. Autologous T-cells from eligible patients were isolated, transduced with a lentiviral vector containing the MAGE-A4c1032 TCR, and expanded. Prior to ADP-A2M4 infusion, pts received a lymphodepletion regimen of cyclophosphamide and fludarabine. Cohorts 1, 2, 3, and expansion were to receive transduced cell doses of up to: 0.12 × 109, 1.2 × 109, 6 × 109, and 10 x 109, respectively. Results: As of 23 October 2019, 9 pts were treated in dose escalation with no DLTs; 25 pts were treated in expansion. Median age was 56.5 yr (range: 31-78). All pts received prior chemotherapy. Most common ( > 30%) AEs ≥Grade 3 were lymphopenia, leukopenia, neutropenia, anemia, thrombocytopenia, and febrile neutropenia. Two pts had trial-related deaths (aplastic anemia and CVA) leading to modification of the lymphodepletion regimen and eligibility criteria. In Cohort 3/expansion (28 pts), Best Overall Response was PR (7), SD (11), PD (5), non-evaluable (5). All PRs, at the time of data cut-off, were in patients with synovial sarcoma. Transduced T-cells were detectable in all patients. Tumor infiltration of SPEAR T-cells was detectable in several cohort 3/expansion pts. Conclusions: The Phase I single agent ADP-A2M4 trial will complete enrollment shortly and updated data will be presented. ADP-A2M4 shows promising efficacy and a manageable safety profile at a dose range of 1.2 – 10 × 109. Clinical activity in various tumors has led to a separate on-going low dose radiation sub-study of this trial, a Phase II trial in sarcoma (SPEARHEAD-1, NCT04044768), and a Phase I trial (SURPASS, NCT04044859) with ADP-A2M4CD8, a next-generation SPEAR T-cell targeting MAGE-A4. Clinical trial information: NCT03132922.

Patient-reported global health predicts adverse health outcomes in a cohort of patients with advanced sarcoma

e23547

Background: Given the rare nature of sarcoma cancers and the sometimes severe treatment-related effects of chemotherapy, many patients with sarcoma face quality of life issues during treatment. Unplanned hospital admission and emergency room (ER) visits can occur from uncontrolled symptoms and ultimately delay treatment regimens and negatively impact quality of life. The PROMIS Global Health v1.2 (PROMIS-10) surveys are validated tools to assess patients’ physical and mental well-being at the time of the survey. We sought to evaluate the correlation between PROMIS-10 scores and adverse outcomes of interest, including unplanned admissions/ED visits and patient mortality. Methods: All patients currently seen in the Sarcoma Clinics at Ohio State University routinely complete the PROMIS-10 survey at each clinic visit. For this pilot study, we collected the raw and normalized t-scores for PROMIS-10 surveys for all patients consented to The Ohio State University Sarcoma Registry (OSU-14242) from 6/1/2018 to 11/20/2019. We also collected data on unplanned hospital admission/ED visits and mortality data for each patient. Results: A total of 864 surveys for 112 patients were collected for the study period. The median number of surveys answered per patient was 6. Mean global physical t-scores (43.7 ± 8.5) and mental t-scores (47.9 ± 9.2) were lower than reference scores for the general US population (p < 0.001). 109 of 112 patients experienced an unplanned admission or ED visit during the study, with a total of 270 such encounters during the study period. PROMIS-10 scores were slightly but significantly lower for patients experiencing an admission or ED visit within 30 days of taking the survey (physical: 41.9 vs 44.1, p = 0.006; mental: 46.4 vs 48.2, p = 0.035). A total of 26 patients died during the study period; surveys completed prior to death were consistent with a greater level of physical and mental distress, with the median physical t-score = 34.9 (range: 23.5 – 50.8) and mental t-score = 43.5 (range: 33.8 – 67.6). Conclusions: We showed that we are able to obtain worthwhile data to objectively evaluate patients’ physical and mental well-being through survey data during cancer treatment. We are currently performing additional confirmatory analysis of the predictive value of the PROMIS-10 survey for adverse events and for treatment-related complications.

Development of urine metabolomic biomarkers for ifosfamide-induced encephalopathy (IIE) in soft tissue sarcoma patients

e23534

Background: In the treatment of sarcomas, high doses of ifosfamide in combination with other chemotherapeutic agents remains a backbone of cytoreductive therapy. Unfortunately, IIE remains a prevalent treatment side effect with a reported prevalence of 10-20%. Although mild hypoalbuminemia has previously been implicated as a risk factor, its risk contribution is modest. There are no clinically significant biomarkers which may help identify IIE patents. Given the correlation with hypoalbuminemia to renal function, we hypothesized that urinary metabolites may serve as potential early biomarkers for IIE. Here we report our interim biomarker findings as part of our sarcoma metabolomic biocollection protocol. Methods: All sarcoma patients that received ifosfamide were identified (2011-2020) through a sarcoma registry (OSU-14242). Development of IIE was obtained through chart review. For consented patients undergoing adriamycin and ifosfamide treatment, urine samples were obtained over the course of 5 days and two treatment cycles (OSU IRB: 2014C0181). Urine samples were subjected to targeted metabolomic analysis for known ifosfamide metabolites and untargeted metabolomic profiling. LC-MS was performed on a Sciex TripleTOF 5600 and data preprocessing with XCMS. For each metabolite, mean abundance and slope, as determined by linear regression across all time points, was compared to development of IIE coded as a binary variable. Results: A total of 70 sarcoma patients were identified, of whom 11 developed IIE for a prevalence of 15.7%. Baseline values at the start of ifosfamide treatment were a mean albumin of 3.7 g/dL (+/- 0.38) and a mean serum creatinine of 0.79 mg/dL (+/- 0.26). Both values are within our “normal range”. For seven of these patients, of whom one developed IIE, we successfully collected additional metabolomic profiling. From these data, 6,030 features (representing metabolites or metabolite fragments) were measured. Time course plots of drug metabolites for which pure standards were run showed an increase of expected chemotherapy-related metabolites at the beginning of each cycle, with inter- and intra-patient variability. IIE was associated with 70 metabolite features (by mean abundance, FDR < 5%). Metabolite identification of putative features based on tandem mass spectrometry is in process. Conclusions: This pilot study indicates that urine metabolomic analysis is feasible and may identify IIE biomarkers. We expect to confirm these results once ongoing specimen analysis is complete.

Sarcoma Treatment Efficacy Portal (STEP): A novel informatics portal providing real-time, real-world outcomes to clinicians

e23538

Background: There are currently no informatics tools that are capable of providing complex clinical decision support using real-world outcomes (RWO) for patients with sarcoma. Although existing nomograms can provide prognostic scores based on clinical or genomics features, they typically are static and lack the ability to compare outcomes for patients managed with alternative treatment strategies. To address this need, we present STEP, a Sarcoma Treatment Efficacy Portal, a web-based tool designed for real-time exploration and visualization of patient data with the potential to be integrated into clinical decision workflows during outpatient visits. Methods: At The Ohio State University, clinical histories and omics data for sarcoma patients are captured in our prospective Sarcoma Registry (NCT0267796). STEP is an interactive web-based tool built in R/Shiny and supported by a pipeline written Python that processes, transforms, and caches clinical data extracted from the Sarcoma Registry in near real-time. Protected health information (PHI) is stored on a secure HIPAA compliant server behind the hospital firewall and migrated to a secure, deidentified staging database. Results: The STEP system is powered by detailed treatment specific data elements that are continuously abstracted for over 400 patients with bone and soft tissue sarcoma. This consists of manually annotated clinical histories in addition to nearly 10 million discrete data points are pulled from the EHR (labs, ICD-9/10 codes, medications, omics data). Importantly, STEP includes a cohort builder which allows users to define a treatment group of interest though any number of variables including tumor histology, chemotherapy, and omic features of interest. For any predefined cohort, STEP can provide information on overall survival and response to a variety of treatments. It also provides sorting mechanisms for identifying candidate treatments. A secure web interface allows a simple integration into a busy clinic flow. Conclusions: STEP provides a first in class, convenient, clinician friendly platform for delivering access to real-time, real-world treatment outcomes (RWO) in patients with a diagnosis of bone or soft tissue sarcoma. Additional usability testing is forthcoming.

A randomized phase II study of MLN0128 (M) versus pazopanib (P) in patients (pt) with advanced sarcoma (Alliance A091304)

11562

Background: Soft tissue sarcoma (STS) is a heterogeneous malignancy of connective tissue. Although mTOR is implicated in STS pathogenesis, clinical activity from mTORC1 inhibitors is modest. M, a potent selective mTORC1/mTORC2 inhibitor, was more effective in STS preclinical models than inhibitors of mTORC1, IGF1R and mTORC1+IGF1R, owing to more complete suppression of PI3K/AKT/mTOR and abrogation of feedback AKT activation. P, an oral multikinase inhibitor, is approved for non-adipocytic STS and often used after progression (PD) on chemotherapy. In phase 1, the RP2D of M was 30 mg weekly. A091304 was to evaluate M as a novel targeted therapy for STS. Methods: In A091304, pts were randomized 1:1 to M 30 mg weekly or P 800 mg daily. Eligibility required Eastern Cooperative Oncology Group PS ≤ 1, progression on ≥ 1 prior chemotherapy and specific STS subtypes (cohort 1: UPS; 2: LMS; 3: MPNST, SS). Crossover to M was allowed after PD on P. 1° endpoint was progression-free survival (PFS). Assuming median PFS of P was 4.6 months (mo), 98 pts yielded 80% power to detect a hazard ratio of 0.66 favoring M [1-sided test, alpha = 0.15] and including 1 planned futility analysis. 2° endpoints were response rate, clinical benefit rate (CBR) at 4 mo and safety. After 4 of the first 12 pts randomized to P experienced ≥ grade (gr) 3 toxicity, the study was amended to begin at P 400 mg, allowing titration to 800 per investigator discretion. Results: After protocol amendment, 114 pt underwent randomization (M: 56, P: 58), and 111 initiated treatment. Median PFS was 2 mo for M and 2.1 mo for P (HR = 1.47; 1-sided 85% upper confidence boundary = 1.85), with 2 partial responses in each arm. CBR was 5.4% for M and 13.8% for P. Median OS was 10.7 mo for M and 13.9 mo for P (HR = 1.41; 95% CI 0.80-2.49). 26/43 pt with PD on P crossed over to M. Median PFS after crossover was 1.8 mo (95% CI 1.5-3.5). Gr 3 drug-related adverse events (AEs) occurred in 36% on M and 41% on P; gr 4 toxicity was rare. AEs were consistent with known effects of M and P. Conclusions: P at 400 mg daily (allowing escalation to 800 mg per investigator discretion) demonstrated a shorter PFS as compared prior randomized studies with P. Despite this, M failed to demonstrate superior clinical activity as compared to P at the interim analysis. Further work will examine activity within histology-specific cohorts and evaluate available tissue samples for evidence of pharmacodynamic activity. Support: U10CA180821, U10CA180882, U10CA180888, UG1CA233324 (SWOG); https://acknowledgments.alliancefound.org . Clinical trial information: NCT02601209 .

A multicenter phase II study of nivolumab +/- ipilimumab for patients with metastatic sarcoma (Alliance A091401): Results of expansion cohorts

11511

Background: In the open-label multicenter phase II study, A091401, nivolumab (N) and nivolumab+ipilimumab (N+I) demonstrated a confirmed response rate (RR) of 5% and 16%, respectively in patients (pts) with advanced sarcoma (D’Angelo SP et al Lancet Oncology 2018). Responses occurred in undifferentiated pleomorphic sarcoma (UPS), myxofibrosarcoma, leiomyosarcoma, sarcoma not otherwise specified and alveolar soft part sarcoma. Here, we report efficacy of N and N+I, in each of 3 expansion cohorts [gastrointestinal stromal tumor (GIST), UPS and dedifferentiated liposarcoma (DDLS)]. Methods: Pts refractory to ≥ 1 regimen(s) were randomized (non-comparative) to receive either N [N (3 mg/kg q2W)] or N+I [N (3 mg/kg Q3W x4, then Q2W) plus I (3 mg/kg q3W x4)]. The primary endpoint was 6 month confirmed RR (RECIST v1.1). For UPS and DDLS, 2 confirmed responses in the 1st 12 evaluable pts was needed (85% power, 1-sided alpha=0.15, 5 v 25% RR). For GIST, a confirmed response in the 1st 9 evaluable pts expanded enrollment to 24 (80% power, 1-sided alpha=0.10, 5 v 20% RR). Other endpoints: adverse events (AEs, TRAEs), progression-free and overall survival (PFS, OS), and correlatives. Results: See table. Clinical trial information: NCT02500797 . Conclusions: Neither N or N+I lead to confirmed responses in GIST. In DDLS and UPS, the primary response endpoint was met with N+I but not with N alone (RR 14% for N+I vs. 7% and 8% for N alone). For the GIST cohort TRAE was higher with N+I, holding enrollment as required per protocol. There remains a pressing need to determine genomic and clinical biomarkers of response, resistance and toxicity. Correlative analyses (whole exome sequencing, multiplex IHC and RNAseq) are in progress. Support: U10CA180821, U10CA180882; ClinicalTrials.gov Identifier: NCT02500797. [Table: see text]

The Adrenal Gland as a Sanctuary Site of Metastases After Pembrolizumab Treatment: A Case Series

Therapeutic agents targeting the PD-1/PD-L1 axis have shown durable clinical responses in patients with various cancer types. Although objective responses are common, intrapatient heterogeneous responses have been described, and the mechanism for the different organ responses remains unknown. We present a series of patients in whom a lack of response was noted solely in the adrenal glands. This is the first case series describing 3 patients with heterogeneous patterns of response to pembrolizumab with progression of adrenal metastatic disease despite objective response (complete or partial response) in all other sites of metastatic disease. Two patients, one with melanoma and one with uterine carcinosarcoma, underwent robotic adrenalectomy for enlarging adrenal metastases. An additional patient with melanoma underwent laparotomy with attempted resection, but infiltration of the adrenal tumor into the inferior vena cava prohibited safe excision. This report provides additional insight into the heterogeneous patterns of disease response to anti-PD-1 therapy, highlighting the adrenal gland as a potential sanctuary site for this immunotherapy. These cases display the potential benefit of early surgical resection in this scenario and the pitfalls of delaying referral to a surgeon for assessment of operative intervention.

Common Secondary Genomic Variants Associated With Advanced Epithelioid Hemangioendothelioma

IMPORTANCE

Epithelioid hemangioendothelioma (EHE) is a rare, malignant vascular sarcoma characterized in most cases by a WWTR1-CAMTA1 fusion. The clinical course of EHE exhibits a dual nature. The condition is often indolent but can rapidly grow and metastasize unpredictably. No biomarkers to date are available to predict this phenotype. The hypothesis of this study was that better defining the genomic landscape of EHE using next-generation sequencing could offer additional therapies and insight into clinical outcomes.

OBJECTIVE

To characterize secondary EHE genomic alterations and their association with clinical outcomes.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter, cross-sectional, retrospective study of next-generation sequencing results collected from participants diagnosed with EHE. Data were abstracted between May 1, 2013, and May 31, 2019. This analysis was conducted from January through June 2019. Summary genomic data were provided by commercial genomic testing companies.

MAIN OUTCOMES AND MEASURES

Presence or absence of secondary pathogenic genomic variants and their association with disease stage and clinical features.

RESULTS

A total of 49 participants with EHE were assessed for the presence or absence of secondary genomic variants. Of these, 32 (65.3%) were female; the mean (SD) age at diagnosis was 49.9 (18.3) years (range, 11-81 years). In all, 46 participants (93.9%) had confirmed WWTR1-CAMTA1 fusion; 26 participants (57.1%) exhibited a pathogenic genomic variant secondary to the WWTR1-CAMTA1 fusion; and 9 participants (18.4%) exhibited potentially targetable genomic variants. Commonly altered genes included CDKN2A/B, RB1, APC, and FANCA. Participants older than 45 years at diagnosis had an increased prevalence of secondary genomic variants that was not statistically significant (65.6% vs 38.5%; difference, 27.1%; 95% CI, -3.5% to 58.0%; P = .16) and were more likely to have a clinically targetable variant (28.1% vs 0%; difference, 28.1%; 95% CI, 11.2%-40.2%; P = .03). In 14 participants with clinical data available, those with stage III/IV EHE were more likely to exhibit a secondary pathogenic genomic variant (80% vs 0%; difference, 80%; 95% CI, 55.2%-100%; P = .006). Participants with stage III/IV EHE were diagnosed at an older age (mean [SD] age, 54.6 [14.1] years vs 31.7 [16.0] years; P = .05) and had elevated WWTR1-CAMTA1 fusion expression that was not statistically significant (mean [SD] expression, 677 [706] copies vs 231 [213] copies; P = .20).

CONCLUSIONS AND RELEVANCE

Although EHE exhibits few secondary genomic variants, presence of key secondary variants may be prognostic for aggressive EHE. Further research is needed to confirm this finding and determine whether more intensive upfront treatment is necessary for these patients.

Inflammatory Myofibroblastic Tumor Driven by Novel NUMA1-ALK Fusion Responds to ALK Inhibition

Inflammatory myofibroblastic tumors (IMTs) are soft tissue neoplasms with rare metastatic potential. Approximately half of IMTs are positive for an ALK rearrangement, and ALK inhibitors have been used successfully in the treatment of IMTs with a variety of ALK fusions. This report describes a 21-year-old woman with an aggressive, metastatic IMT with a novel NUMA1-ALK fusion that showed a dramatic response to the ALK inhibitors crizotinib and alectinib. To our knowledge, this report provides the first published description of an IMT with a NUMA1-ALK fusion. The patient's aggressive IMT responded favorably to crizotinib and alectinib, suggesting that ALK inhibitors may be effective in IMT with NUMA1-ALK fusions. We review published reports of ALK-driven IMTs that have received ALK inhibitor therapy and suggest characteristics that may be associated with favorable response to treatment. We also discuss the strengths and limitations of immunohistochemistry, fluorescence in situ hybridization, and next-generation sequencing in the diagnosis and management of IMTs.

Determinants of secondary alterations in WWTR1-CAMTA1 fusion epithelioid hemangioendothelioma

11045

Background: Epithelioid hemangioendothelioma (EHE) is a rare vascular sarcoma characterized by the WWTR1- CAMTA1 fusion ( WC-F) in a majority of cases. EHE demonstrates a biphasic clinical course; remaining indolent for many years before suddenly demonstrating aggressive progression. Cell cycle mutations have been previously noted to account for some secondary alterations; however, little is known regarding the chronicity of these secondary alterations or their clinical implications. Here we present the largest assessment of secondary genomic variants and their clinical import. Methods: Comprehensive genomic profiling from 45 WC-F positive EHE patients (pts) were provided by Foundation Medicine (FMI). 8 of these 45 pts were treated at The Ohio State University (OSU) and were evaluated retrospectively through chart review. Known deleterious alterations, variants of unknown significance (VUS), and genomic copy quantification for the WC-F was included in our analysis. Targetable gene variants were defined by OncoKB. Chi-square and student’s t-tests were used as appropriate. Results: Genomic copy number of the WC-F best fit a log-normal distribution (range: 13-2,131 copies). 20 pts (44%) did not exhibit any secondary genomic variants. The most commonly altered genes included: CDKN2A/B (7 variants), RB1 (3 variants), and ATRX (3 variants). Commonly identified pathways included: cell cycle (9 pts, 20.0%), epigenetic modulators (7 pts, 15.6%), and DNA damage repair (7 pts, 15.6%). Eight pts exhibited targetable gene variants (18%) as defined by OncoKB. Subjects ≥50 years of age exhibited a greater proportion of clinically targetable variants (27.6% vs 0%; p = 0.02). Pts with a secondary genomic variant exhibited elevated WC-F copy numbers (p < 0.001). OSU pts with aggressive EHE were more likely to have a second genomic variant (80% vs 0%; p = 0.03) when compared to indolent EHE, with trends toward higher WC-F copy numbers (809±315 vs 207±147; p = 0.2) and older age at diagnosis (59.5±5.5 vs 36.7±8.8; p = 0.1). Conclusions: In this study, secondary genomic variants in WC-F driven EHE are more common in older patients ( > 50 yo). Further, the presence of secondary genomic variants is associated with an aggressive phenotype and may drive poor prognosis. Prospective research is needed to confirm these findings.

Phase 1 Study of Ipilimumab Combined With Whole Brain Radiation Therapy or Radiosurgery for Melanoma Patients With Brain Metastases

PURPOSE

We performed a phase 1 study to determine the maximum tolerable dose and safety of ipilimumab with stereotactic radiosurgery (SRS) or whole brain radiation therapy (WBRT) in patients with brain metastases from melanoma.

METHODS AND MATERIALS

Based on the intracranial disease burden, patients underwent WBRT (arm A) or SRS (arm B). The ipilimumab starting dose was 3 mg/kg every 3 weeks, starting on day 3 of WBRT or 2 days after SRS. The ipilimumab dose was escalated to 10 mg/kg using a 2-stage, 3+3 design. The primary endpoint was to determine the maximum tolerable dose of ipilimumab combined with radiation therapy. The secondary endpoints were overall survival, intracranial and extracranial control, progression-free survival, and toxicity. The ClinicalTrials.gov registration number is NCT01703507.

RESULTS

The characteristics of the 16 patients enrolled between 2011 and 2014 were mean age, 60 years; median number of brain metastases, 2 (range 1->10); and number with EC disease, 13 (81%). Treatment included WBRT (n=5), SRS (n=11), and ipilimumab 3 mg/kg (n=7) or 10 mg/kg (n=9). The median follow-up was 8 months (arm A) and 10.5 months (arm B). A total of 21 grade 1 to 2 neurotoxic effects occurred, with no dose-limiting toxicities. One patient experienced grade 3 neurotoxicity before ipilimumab administration. Ten additional grade 3 toxicities were reported, with gastrointestinal toxicities (n=5; 31%) the most common. No patient developed grade 4 or 5 toxicity. The median progression-free survival and overall survival in arm A was 2.5 months and 8 months and in arm B was 2.1 months and not reached, respectively.

CONCLUSIONS

Concurrent ipilimumab 10 mg/kg with SRS is safe. The WBRT arm was closed early because of slow accrual but demonstrated safety with ipilimumab 3 mg/kg. No patient experienced dose-limiting toxicity. Larger studies, including those with combination checkpoint inhibitor therapy and SRS, are warranted.

A pilot study of NY-ESO-1c259 T cells in subjects with advanced myxoid/round cell liposarcoma (NCT02992743)

TPS3097

Background: Myxoid/round cell liposarcomas (MRCLS) account for 6-10% of soft tissue sarcomas. Although a chemosensitive tumor, metastatic MRCLS has a poor prognosis and is inevitably fatal. More effective, durable and less toxic therapies are needed. NY-ESO-1 is a cancer/testis antigen that is expressed in 80-90% of MRCLS tumors. This study will evaluate the safety and efficacy of genetically engineered affinity enhanced autologous NY-ESO-1c259T cells recognizing an NY-ESO-1 derived peptide complexed with HLA-A*02 in MRCLS. Methods: This open label phase I/II non-randomized pilot study will evaluate efficacy (overall response rate by RECIST v1.1, time to response, duration of response, progression free survival, overall survival), safety, and translational research endpoints. Patients must meet these criteria: ≥ 18 yrs old; HLA-A*02:01, *02:05 or *02:06 positive; have advanced (metastatic or inoperable) MRCLS expressing NY-ESO-1 at 2+/3+ intensity in ≥30% of tumor cells by IHC; measurable disease; prior systemic anthracycline therapy; have ECOG status 0 or 1; and adequate organ function. Initially, ten patients are planned to be enrolled, with potential to enroll an additional 5 patients. Patients who do not receive the minimum cell dose or who do not receive the T-cell infusion may be replaced. Following apheresis, the T cells are isolated and expanded with CD3/CD28 beads, transduced with a lentiviral vector containing the NY-ESO-1c259 TCR, and 1– 8 × 109 transduced T-cells are infused intravenously on Day 1 after lymphodepletion with fludarabine 30 mg/m2/day and cyclophosphamide 600 mg/m2/day on days -7 to -5. Response is assessed at 4, 8, 12 and 24 weeks, and then every 3 months until confirmation of progression of disease. On study tumor biopsies and blood samples will be evaluated to compare the pre- and post-T cell infusion immune profile for association with treatment outcome. Clinical trial information: NCT02992743.

Phase III study of aldoxorubicin vs investigators' choice as treatment for relapsed/refractory soft tissue sarcomas

11000

Background: Aldoxorubicin (A) is a novel drug that binds covalently to albumin in the circulation, accumulates in tumors and releases doxorubicin in the acidic tumor environment. It has demonstrated enhanced antitumor activity in several murine models and in a phase IIb STS study when compared with doxorubicin. Trial Design: Phase III open-label study evaluating efficacy and safety of A compared to investigators' choice (IC) of treatment in subjects with soft tissue sarcomas (STS) who have relapsed or were refractory to prior chemotherapy. Objectives: (1) Primary: Efficacy of A vs IC: progression-free survival (PFS); (2) Secondary: Efficacy of A vs IC: tumor response (ORR), disease control rate (DCR; CR+PR+SD > 4 months), overall survival (OS) and safety. Methods: A: 350 mg/m2 (260 mg/m2dox. equiv.) iv q3 wks. IC drugs: dacarbazine, doxorubicin, pazopanib, ifosfamide, gemcitabine/docetaxel administered per package insert or study site's standard practice; provided, with G-CSF, by the sponsor. AEs, serum chemistries, CBCs, EKG and ECHOs obtained frequently. CT scans every 6 weeks for 30 weeks, then every 12 weeks; analyzed using RECIST 1.1 by Blinded Independent Central Review. Results: Randomized 433 subjects; 79 countries; 313 (72%) in North America (NA) and 121 (28%) in Rest of World (ROW). Leiomyosarcoma 42.5%, liposarcoma 15%, synovial sarcoma 9%, others 33.5%, L-sarcomas (lipo+leiomyo) 57.5%. Median PFS Total Pop. (months): A= 4.06; IC= 2.96; p = 0.12; HR = 0.82 (0.64-1.06). Median PFS NA (months): A= 4.21; IC= 2.96; p = 0.027; HR = 0.71 (0.53-0.97). Median PFS L-sarcomas (months): A= 5.32; IC= 2.96; p = 0.007; HR = 0.62 (0.44-0.88). DCR Total Pop.(%): A= 30.3; IC= 20.9; p = 0.028; DCR NA (%): A= 32.9; IC= 19.2; p = 0.007; DCR L-Sarcomas (%): A= 37.5; IC= 23.0; p = 0.018. ORR and OS will be reported. TEAEs gr 3 or 4 (%): A= 61.0; IC= 46.4. Trtmt Rel. SAEs (%): A= 27.0; IC= 14.0. TEAEs leading to Drug Discontinue (%): A= 4.2; IC= 6.3. Trtmt Related Deaths (#); A= 3; IC= 0; LVEF < 50% expected (%): A= 2.8%;Dox = 12.8%. Conclusions: Aldox is an active, well-tolerated drug for treating relapsed or refractory STS and is significantly better than standard treatments for patients with L-sarcomas. Clinical trial information: NCT02049905.

Patterns of major wound complications following multidisciplinary therapy for lower extremity soft tissue sarcoma

BACKGROUND AND OBJECTIVES

The purpose of this study was to determine the pattern and timing of major wound complications (MWCs) in patients at our institution who received multimodality treatment for lower extremity soft tissue sarcoma (LE-STS) and to evaluate the impact of MWCs on tumor control and patient outcomes.

METHODS

The medical records of 102 LE-STS patients treated with limb-sparing surgery and radiation therapy were reviewed. MWCs were defined as secondary operations with anesthesia, seroma/hematoma aspiration, admission for IV antibiotics, or persistent deep packing.

RESULTS

MWCs occurred in 22% of patients, with 45% of events occurring >120 days after resection. On multivariate analysis, preoperative external beam radiation therapy (EBRT) (OR 4.29, 95% CI 1.06-17.40, P = 0.042) and skin graft placement (OR 6.39, 95% CI 1.37-29.84, P = 0.018) were found to be independent predictors of MWCs. MWC occurrence did not predict for chronic toxicity and did not impact tumor control or survival.

CONCLUSIONS

A considerable proportion of MWCs occur >120 days from surgical resection with preoperative EBRT and skin graft placement independent predictors for MWCs. While an additional source of morbidity, MWC occurrence did not impact tumor control, nor did it predict for chronic toxicity. J. Surg. Oncol. 2016;114:385-391. © 2016 Wiley Periodicals, Inc.

Angiosarcoma: A rare malignancy with protean clinical presentations

Angiosarcoma is a rare form of soft tissue sarcoma. Primary small intestinal angiosarcomas are especially uncommon. The clinical presentations of small intestinal angiosarcomas vary but gastrointestinal (GI) bleeding is a frequent finding. We present a case of persistent GI bleeding of unknown etiology culminating in operative exploration demonstrating a primary small intestinal angiosarcoma. A discussion of the diagnosis, pathology, and management of angiosarcoma with a review of the current literature is provided including molecular genetics, difficult cases, and current treatment options.

Analysis of BAP1 Germline Gene Mutation in Young Uveal Melanoma Patients

BACKGROUND

To evaluate the prevalence of BAP1 germline mutations in a series of young patients with uveal melanoma (UM), diagnosed before age 30.

MATERIALS AND METHODS

The study was carried out on 14 young uveal melanoma patients (average age 21.4 years, range 3 months to 29 years). Germline DNA was extracted from peripheral blood. BAP1 sequencing was carried out using direct sequencing of all exons and adjacent intronic sequences. We also tested for germline mutations in additional melanoma-associated candidate genes CDKN2A and CDK4 (exon 4).

RESULTS

We identified one patient with a pathogenic mutation (c. 1717delC, p.L573fs*3) in BAP1. This patient was diagnosed with UM at age 18 years and had a family history of a father with UM and a paternal grandfather with cancer of unknown origin. One additional patient had an intronic variant of uncertain significance (c.123-48T > G) in BAP1 while the remaining 12 patients had no alteration. None of the patients had CDKN2A or CDK4 (Exon 4) mutations. Family history was positive for a number of additional malignancies in this series, in particular for cutaneous melanoma, prostate, breast and colon cancers. There were no families with a history of mesothelioma or renal cell carcinoma.

CONCLUSIONS

This study suggests that a small subset of patients with early onset UM has germline mutation in BAP1. While young patients with UM should be screened for germline BAP1 mutations, our results suggest that there is a need to identify other candidate genes which are responsible for UM in young patients.

MMAD: microarray microdissection with analysis of differences is a computational tool for deconvoluting cell type-specific contributions from tissue samples

BACKGROUND

One of the significant obstacles in the development of clinically relevant microarray-derived biomarkers and classifiers is tissue heterogeneity. Physical cell separation techniques, such as cell sorting and laser-capture microdissection, can enrich samples for cell types of interest, but are costly, labor intensive and can limit investigation of important interactions between different cell types.

RESULTS

We developed a new computational approach, called microarray microdissection with analysis of differences (MMAD), which performs microdissection in silico. Notably, MMAD (i) allows for simultaneous estimation of cell fractions and gene expression profiles of contributing cell types, (ii) adjusts for microarray normalization bias, (iii) uses the corrected Akaike information criterion during model optimization to minimize overfitting and (iv) provides mechanisms for comparing gene expression and cell fractions between samples in different classes. Computational microdissection of simulated and experimental tissue mixture datasets showed tight correlations between predicted and measured gene expression of pure tissues as well as tight correlations between reported and estimated cell fraction for each of the individual cell types. In simulation studies, MMAD showed superior ability to detect differentially expressed genes in mixed tissue samples when compared with standard metrics, including both significance analysis of microarrays and cell type-specific significance analysis of microarrays.

CONCLUSIONS

We have developed a new computational tool called MMAD, which is capable of performing robust tissue microdissection in silico, and which can improve the detection of differentially expressed genes. MMAD software as implemented in MATLAB is publically available for download at http://sourceforge.net/projects/mmad/.

Identification of novel melanoma gene expression signatures using a Bayesian approach to filter out gene expression noise from normal tissues

e19053

Background: Identification of pertinent gene expression signatures may be confounded by failure to account for admixture of tumor specimens with normal tissue. We propose a novel method for filtering out gene expression “noise” from normal tissues in a set of melanoma samples derived from the NCBI Gene Expression Omnibus (GEO) public database. Methods: Using customized software implemented in MATLAB, we performed a preliminary search of GEO using the query term “melanoma”. We manually identified 695 clinical samples within 19 different gene expression studies (median 43 samples per series). Gene expression results were merged across different platforms using rank normalization for the target gene of the respective probes. Standardized gene expression signatures for 36 normal tissues were identified in GEO (GSE2361). We performed a modified sparse Bayesian factor regression analysis that incorporated signatures of normal tissues. Additional regression allowed for discovery of latent factors characteristic of melanoma subtypes. Pathway analysis was performed using Ingenuity Pathway Analysis (IPA) on characteristic genes for inferred melanoma-specific latent factors. Results: Normal tissue contributed significantly to the reported gene expression profiles, explaining a median of 11.5% of specimen variability (range 1.3-55.0%). In a subset analysis of 40 primary or in situ melanoma lesions versus 16 metastatic lesions (GSE7553), primary lesions were more likely contaminated with genes characteristic of normal skin (p<0.001). The top 5 latent factors explained a median of 17.0% of residual sample variance (range 0.6-64%). On IPA analysis, latent factor 1 was strongly associated with dermatologic disease (p = 7.46 e-36), latent factor 2 was associated with inflammatory response (p = 9.71e-25), and latent factor 3 was associated with upregulation of the MITF transcription factor regulation (p = 4.16e-19). Conclusions: Appropriate methods that filter out normal tissue contamination of melanoma specimens can improve our understanding of gene expression patterns in melanoma subtypes, and potentially improve future translational studies.

Thyroid cancer: pathogenesis and targeted therapy

Therapeutic options for advanced, unresectable radioiodine-resistant thyroid cancers have historically been limited. Recent progress in understanding the pathogenesis of the various subtypes of thyroid cancer has led to increased interest in the development of targeted therapies, with potential strategies including angiogenesis inhibition, inhibition of aberrant intracellular signaling in the MAPK and PI3K/AKT/mTOR pathways, radioimmunotherapy, and redifferentiation agents. On the basis of a recent positive phase III clinical trial, the RET, vascular endothelial growth factor receptor (VEGFR), and epidermal growth factor receptor (EGFR) inhibitor vandetanib has received FDA approval as of April 2011 for use in the treatment of advanced medullary thyroid cancer. Several other recent phase II clinical trials in advanced thyroid cancer have demonstrated significant activity, and multiple other promising therapeutic strategies are in earlier phases of clinical development. The recent progress in targeted therapy is already revolutionizing management paradigms for advanced thyroid cancer, and will likely continue to dramatically expand treatment options in the coming years.