Chemotherapy is an efficient treatment in primary CNS MALT lymphoma

BACKGROUND

Mucosae-associated lymphoid tissue (MALT) lymphomas are a rare and poorly understood form of primary central nervous system lymphoma (PCNSL). The aim of this study was to better describe these tumors, their management and their long-term prognosis.

METHODS

Patients with primary CNS MALT lymphoma (PCNSML) were retrospectively selected from the database on PCNSL of the Pitié-Salpêtrière Hospital.

RESULTS

Of 662 PCNSL, 11 (1.7%) PCNSML (9 females and 2 males, median age: 56 years) were selected. The median time from first symptoms to diagnosis was 13 months. Location was dural in 8 cases and parenchymal in 3 cases. The disease was multifocal/diffuse in 7 cases. In first line, all patients received chemotherapy (high-dose methotrexate (HD-MTX) based chemotherapy (n = 4) and non-HD-MTX-based chemotherapy (n = 7)), preceded by surgery in 4 cases. None received radiotherapy. According to the IPCG (International PCNSL Collaborative Group) criteria, the overall response rate was 7/11 (64%). At latest news, 5 patients had persistent contrast enhancement, stable with no treatment since a median of 57 months, raising the question of complete response despite persisting contrast enhancement. No patient developed neurotoxicity except for one patient who subsequently received radiotherapy. The median follow-up was 109 months. The median progression-free survival was 78.0 months and the 10-year overall survival rate was 90%.

CONCLUSION

This is the largest series demonstrating that chemotherapy is an efficient treatment in PCNSML, with an excellent long-term outcome and the absence of neurotoxicity, and calling into question the relevance of the IPCG criteria for the evaluation of response.

Rituximab-Lenalidomide-Ibrutinib Combination for Relapsed/Refractory Primary CNS Lymphoma: A Case Series of the LOC Network

BACKGROUND AND OBJECTIVES

To evaluate the efficacy and tolerance of the association rituximab-lenalidomide-ibrutinib (R²I) in relapsed/refractory (R/R) primary CNS lymphoma (PCNSL).

METHODS

R/R PCNSL patients treated with R²I were retrospectively selected and analyzed from the French LOC database.

RESULTS

Fourteen patients (median age: 63 years, median Karnofsky Performance Status: 75%) received R²I, administered after a median of 2 previous lines of chemotherapy, including autologous stem cell transplantation (ASCT) in 5 cases. The best response was complete response in 4/14 patients and partial response in 4/14 patients, achieved in a median of 2.5 months. Three responder patients received consolidation treatment (WBRT: N = 2, ASCT: N = 1) after R²I, and R²I served as a bridge before CAR-T cell therapy for one patient. R²I was discontinued due to toxicity in 3/14 patients. There were no toxicity-related deaths.

DISCUSSION

The R²I combination resulted in a high rate of response of rapid-onset in heavily pretreated patients with poor prognosis, with manageable toxicity, and allowed 3 patients to proceed to consolidation. Although preliminary, these results support the use of R²I for R/R PCNSL failing conventional chemotherapies.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that combination of rituximab-lenalidomide-ibrutinib induces a high rate of response in heavily pretreated R/R PCNSL.

P14.48 Extracerebral relapses of primary CNS lymphoma (PCNSL): a LOC network retrospective study

BACKGROUND

Classically PCNSL remain confined within the CNS throughout their evolution for reasons still unknown (> 80% cerebral relapses). The aim of this study was to describe the characteristics and outcomes of the rare extracerebral relapses of PCNSL.

MATERIAL AND METHODS

This is a multicenter, retrospective study. We included all immunocompetent patients newly diagnosed with diffuse large B-cell PCNSL registered in the national LOC network database since 2010 and followed prospectively, who presented an extracerebral relapse, pure (extracerebral only site) or associated with concomitant CNS relapse (mixed). All had body scan and/or TEP -CT at diagnosis work up.

RESULTS

Of the 1968 PCNSL included in the database, 29 (1.5%) patients presented a systemic relapse [median age 71 years, median KPS 70% at relapse], either pure (n=19) or mixed (n=10), with a histological confirmation in 19 cases (66%). The median delay between initial diagnosis and systemic relapse was 15 months [2–49 months], with 5 very early relapses (<8 months) and 10 late relapses (>21 months). 27 patients had symptoms, 21 related to the location of relapse and 6 with only general symptoms. The localization was thoracic (n=11), abdominal/pelvic (n=14), head/neck (n=6) and limbs (n=9). We found visceral (n=24, 83%), including testis in 5 (28%) men and breast in 3 (27%) women, lymph node (n=12, 41%) and peripheral nervous system (PNS) (n=8, 28%; 4 plexus and 4 extradural roots) involvement. 27 patients were treated with chemotherapy, either with only systemic target (n=8) (R-CHOP alone) or mixed systemic and CNS target (n=19) (R-CHOP-MTX, R-ICE, GEMOX, RDHAC) and consolidated by high-dose chemotherapy with autologous stem cell transplantation (HCT-ASCT) in 4 cases [median age 55 years, median KPS 80%], with 34% of complete response. After systemic relapse, median progression-free survival was 8 months and overall survival (OS) was 9 months, 15 months for pure systemic and 4.5 months for mixed relapses. KPS>70%, pure systemic relapses and complete response were significantly associated with higher OS in univariate analysis.

CONCLUSION

Extracerebral PCNSL relapses are very rare, mainly extranodal and involve a large spectrum of anatomical sites, the most frequent being testis, breast and PNS. Prognosis was worse in case of mixed relapse than in pure systemic relapse that was similar to non PCNSL lymphomas. Very early relapses raise the question of misdiagnosed occult extracerebral lymphoma at diagnostic work up that should include systematically a FDG PET-CT. More studies are needed to refine their treatment and to specify the role of HCT-ASCT. Paired tumor tissues at diagnosis (CNS)/relapse (extracerebral) analysis would provide a better understanding of underlying molecular mechanisms.

P03.04 Primary CNS lymphoma of the corpus callosum: presentation and neurocognitive prognosis. Study of a monocentric cohort of 27 patients

BACKGROUND

The corpus callosum (CC) is frequently involved in primary central nervous system lymphomas (PCNSL). The aim of our study was to describe the impact of these lesions on neurocognition of patients presenting with PCNSL of the CC (PCNSL-CC) and their post-therapeutic evolution.

MATERIAL AND METHODS

This is a retrospective single-center study. Patients newly diagnosed at Pitié Salpêtrière Hospital from (1999–2018) were included in this study according to the following criteria: age >18, immunocompetent patient, pathological confirmation (Diffuse Large B cell lymphoma) and CC as main location of the tumor on MRI. Clinical, neuroradiological and neuropsychological data of the patients were collected. In addition, prognostic factors for the neurocognitive outcome of the patients were investigated.

RESULTS

27 patients were included (median age: 67 years, median KPS: 70). At the time of diagnosis, 74% of patients had cognitive impairment and 59% of patients had balance disorders. The cognitive functions most frequently affected were memory and executive functions. Tumor lesions in the CC had a median maximum diameter of 5 cm with a so called “butterfly pattern” in 92% of cases. All patients received a high dose methotrexate based polychemotherapy, including one with radiation therapy, and 67% of patients achieved a complete remission (CR). Median PFS and OS were 33.3 months and 177.9 months respectively. With a median follow-up of 48 months (range 6–156), despite CR, there were still abnormal values in 17% of patients on overall efficiency, 17–55% of patients on executive function tests, 45–55% of patients on memory tests. No significant impaired values were found for visuo-spatial and language tests. Splenial location and age ≥ 60 years were significantly associated with worse episodic memory scores throughout the follow-up.

CONCLUSION

PCNSL-CC are associated with frequent cognitive dysfunctions, especially memory impairment, which may recover only partially despite CR, that warrant specific rehabilitation. Older age (≥ 60) and splenial location have worse neurocognition outcome.

P14.54 Primary central nervous system lymphoma of the spinal cord: a LOC network cohort study

BACKGROUND

Primary central nervous system lymphoma (PCNSL) mainly affects the brain (>90% of the cases), Very little data can be found in the literature on PCNSL with spinal cord localization.

MATERIAL AND METHODS

We present a retrospective study based on the French LOC network database. We selected adult immunocompetentpatients, with a histological or cytological diagnosis of PCNSL, and a spinal cord localization at initial diagnosis.

RESULTS

Of the 2043 PCNSLof the LOC database newly diagnosed since 2011, 14 patients (9 men, median age 68, median Karnofsky performance status 50%)met the selection criteria. The median diagnostic delay was 82 days (min 15-max 1080) compared to 35 days in primary cerebral lymphomas. At diagnosis, walking was impossible in 7/14 patients and 5/14 had indwelling urinary catheter. On MRI, 100% had enlargement of the spinal cord with homogeneous contrast enhancement in 13/14 cases. Spinal cord lesions were unique in 9/14 patients and multiples in 5/14 patients. CSF IL10 level was increased in 6/7 patients. Brain lesions were found in 9/14 patients, located in the posterior fossa in 5/9 cases. The diagnosis was made either on a brain biopsy (N=6), a spinal cord biopsy or surgery (N=5) or the cytologic analysis of the CSF (N=3).4/5 patients had neurological sequel after spinal cord biopsy or surgery. All the patients were treated by high-dose methotrexate-based chemotherapy, followed by spinal cord irradiation (N=1) or autograft (N=2). There was an overall response rate of 71% (complete response in 8/14). 8/14 patients relapsed, 5 in the brain, 2 in the spinal cord, and 1 both in the spinal cord and in the brain. 2-year PFS and OS were 45% and 64%, respectively. Among the long-term responders, 50% remained in wheel chair, while only 10% could walk normally.

CONCLUSION

Considering the high risk of a spinal cord biopsy,the rarity of the disease, as well as the numerous differential diagnoses, the diagnosis of spinal cord lymphoma is difficult. Searching for other lymphomatous locations or assaying CSF IL10 may be helpful in this disease where delay in diagnosis is often prolonged et can cause irreversible handicap.

SARS-CoV-2 infection in patients with primary central nervous system lymphoma

BACKGROUND

Cancer patients may be at higher risk for severe coronavirus infectious disease-19 (COVID-19); however, the outcome of Primary Central Nervous System Lymphoma (PCNSL) patients with SARS-CoV-2 infection has not been described yet.

METHODS

We conducted a retrospective study within the Lymphomes Oculo-Cérébraux national network (LOC) to assess the clinical characteristics and outcome of SARS-CoV-2 infection in PCNSL patients (positive real-time polymerase chain reaction of nasopharyngeal swab or evocative lung computed tomography scan). We compared clinical characteristics between patients with severe (death and/or intensive care unit admission) and mild disease.

RESULTS

Between March and May 2020, 13 PCNSL patients were diagnosed with SARS-CoV-2 infection, 11 (85%) of whom were undergoing chemotherapy at the time of infection. The mortality rate was 23% (3/13), and two additional patients (15%) required mechanical ventilation. Two patients (15%) had no COVID-19 symptoms. History of diabetes mellitus was more common in severe patients (3/5 vs 0/8, p = 0.03). Two patients recovered from COVID-19 after mechanical ventilation during more than two weeks and resumed chemotherapy. In all, chemotherapy was resumed after COVID-19 recovery in nine patients (69%) after a median delay of 16 days (range 3-32), none of whom developed unusual chemotherapy complication nor SARS-Cov2 reactivation.

CONCLUSION

This preliminary analysis suggests that, while being at higher risk be for severe illness, PCNSL patients with COVID-19 might be treated maximally especially if they achieved oncological response at the time of SARS-CoV-2 infection. Chemotherapy might be resumed without prolonged delay in PCNSL patients with COVID-19.

Primary vitreoretinal lymphoma: short review of the literature, results of a European survey and French guidelines of the LOC network for diagnosis, treatment and follow-up

PURPOSE OF REVIEW

The aim of this study was to highlight the diagnostic and management challenges of primary vitreoretinal lymphoma (PVRL) through a review of the literature and a European survey on real-life practices for PVRL.

RECENT FINDINGS

The care of PVRL patients is heterogeneous between specialists and countries. Upfront systemic treatment based on high-dose methotrexate chemotherapy, with or without local treatment, might reduce or delay the risk of brain relapse.Ibrutinib, lenalidomide with or without rituximab, and temozolomide are effective for patients with relapsed/refractory PVRL and should be tested as first-line treatments.

SUMMARY

The prognosis of PVRL remains dismal. No firm conclusion regarding optimal treatment can yet be drawn. The risk of brain relapse remains high. Diagnostic procedures and assessment of therapeutic responses need to be homogenized. Collaboration between specialists involved in PVRL and multicentric prospective therapeutic studies are strongly needed. The recommendations of the French group for primary oculocerebral lymphoma (LOC network) are provided, as a basis for further European collaborative work.

Intravenous high-dose methotrexate based systemic therapy in the treatment of isolated primary vitreoretinal lymphoma: An LOC network study

The treatment of primary vitreoretinal lymphoma (PVRL) remains controversial regarding the use of local, systemic, or combined treatments. The aim of this study was to analyze the efficacy and toxicity of intravenous high-dose methotrexate (IV HD-MTX) based systemic therapy in a uniformly treated population of PVRL patients. From a nationwide French database, we retrospectively selected 59 patients (median age: 70 years, median Karnofsky Performance Status: 90%) with isolated PVRL at diagnosis who received first-line treatment with HD-MTX between 2011 and 2018. 8/59 patients also received a local treatment. No deaths or premature discontinuations of MTX due to toxicity were reported. A complete response was obtained in 40/57 patients after chemotherapy. Before treatment, IL-10 was elevated in the aqueous humor (AH) or in the vitreous in 89% of patients. After treatment, AH IL-10 was undetectable in 87% of patients with a CR/uCR/PR and detectable in 92% of patients with PD/SD. After a median follow-up of 61 months, 42/59 (71%) patients had relapsed, including 29 isolated ocular relapses as the first relapse and a total of 22 brain relapses. The median overall survival, progression-free survival, ocular-free survival and brain-free survival were 75, 18, 29 and 73 months, respectively. IV HD-MTX based systemic therapy as a first-line treatment for isolated PVRL is feasible, with acceptable toxicity, even in an elderly population. This strategy seems efficient to prevent brain relapse with prolonged overall survival. However, the ocular relapse rate remains high. New approaches are needed to improve local control of this disease, and ocular assessment could be completed by monitoring AH IL-10.

A genome-wide association study identifies susceptibility loci for primary central nervous system lymphoma at 6p25.3 and 3p22.1: a LOC Network study

BACKGROUND

Primary central nervous system lymphoma (PCNSL) is a rare form of extra-nodal non-Hodgkin lymphoma. PCNSL is a distinct subtype of non-Hodgkin lymphoma, with over 95% of tumors belonging to the diffuse large B-cell lymphoma (DLBCL) group. We have conducted a genome-wide association study (GWAS) on immunocompetent patients to address the possibility that common genetic variants influence the risk of developing PCNSL.

METHODS

We performed a meta-analysis of 2 new GWASs of PCNSL totaling 475 cases and 1134 controls of European ancestry. To increase genomic resolution, we imputed >10 million single nucleotide polymorphisms using the 1000 Genomes Project combined with UK10K as reference. In addition we performed a transcription factor binding disruption analysis and investigated the patterns of local chromatin by Capture Hi-C data.

RESULTS

We identified independent risk loci at 3p22.1 (rs41289586, ANO10, P = 2.17 × 10-8) and 6p25.3 near EXOC2 (rs116446171, P = 1.95 x 10-13). In contrast, the lack of an association between rs41289586 and DLBCL suggests distinct germline predisposition to PCNSL and DLBCL. We found looping chromatin interactions between noncoding regions at 6p25.3 (rs11646171) with the IRF4 promoter and at 8q24.21 (rs13254990) with the MYC promoter, both genes with strong relevance to B-cell tumorigenesis.

CONCLUSION

To our knowledge this is the first study providing insight into the genetic predisposition to PCNSL. Our findings represent an important step in defining the contribution of common genetic variation to the risk of developing PCNSL.

Leukoencephalopathy with transient splenial lesions related to 5-fluorouracil or capecitabine

BACKGROUND

5-Fluorouracil (5-FU) and its oral prodrug capecitabine have been rarely but consistently associated with acute central nervous system toxicity, including transient leukoencephalopathies involving the splenium of the corpus callosum.

METHODS

We performed a retrospective search in the French Pharmacovigilance database (FPDB) (January 1985-July 2020) for adult patients affected by solid cancers who developed acute toxic leukoencephalopathies with splenial lesions following treatment with 5-FU or capecitabine. A comprehensive review of the literature helped to circumstantiate our findings.

RESULTS

Our research in the FPDB identified six patients who, within 3 days from their first cycle of 5-FU or capecitabine, developed acute neurological symptoms, including gait ataxia (n = 4), dysarthria (n = 3), dysmetria (n = 2), headache (n = 2), and confusion (n = 2). Brain magnetic resonance imaging (MRI) showed T2/FLAIR (fluid-attenuated inversion recovery) hyperintensities in the corpus callosum, with diffusion restriction and no contrast enhancement, generally accompanied by additional alterations in the bilateral supratentorial white matter (n = 5). All patients discontinued the agent supposedly responsible for the toxicity and experienced full recovery after a median of 8.5 days from symptom onset. Control MRI showed a progressive normalization of acute MRI abnormalities. Literature review identified 26 cases with similar clinical and paraclinical characteristics. A single patient from the literature resumed 5-FU at a lower dose, with no recurrent toxicity.

CONCLUSIONS

5-FU and capecitabine might be responsible for acute leukoencephalopathies with transient splenial lesions that are generally reversible upon drug discontinuation. Resuming the agent responsible for toxicity might be feasible in selected cases, after having excluded dihydropyrimidine dehydrogenase deficiency, if expected benefits outweigh the risks.

Infection par le SARS-CoV 2 chez les patients avec lymphome cérébral primitif du système nerveux central : étude préliminaire de la sévérité et des facteurs pronostics

Introduction

Les patients avec cancer semblent à risque d’atteinte sévère de la maladie liée au coronavirus 19 (COVID-19). Néanmoins, ces données ne permettent pas d’établir de recommandations dans les cancers rares.

Objectifs

L’objectif de cette étude était de décrire le pronostic des patients avec lymphome cérébral primitif du système nerveux central (PCNSL) présentant une infection par le SARS-CoV-2.

Patients et méthodes

Nous avons réalisé une étude rétrospective dans le réseau national Lymphomes Oculo-Cérébraux (LOC) afin d’évaluer les caractéristiques cliniques et le devenir après infection par le SARS-CoV-2 chez les patients suivis pour PCNSL (diagnostic par PCR sur prélèvement nasopharyngé ou scanner thoracique évocateur). Nous avons comparé les caractéristiques cliniques des patients avec atteinte sévère (décès ou admission en réanimation) ou modérée et étudié les facteurs pronostics.

Résultats

Entre mars et mai 2020, 13 patients PCNSL ont présenté une infection au SARS-CoV-2, dont 85 % étaient en cours de chimiothérapie. Trente-huit pour cent ont présenté une forme sévère : 23 % de décès, 15 % de ventilation mécanique (VM). Quinze pour cent sont restés asymptomatiques. Un antécédent de diabète était plus fréquent en cas d’atteinte sévère (3/5 vs 0/8, p = 0,03). La chimiothérapie a été reprise chez 9 patients après un délai médian de 16 jours après guérison clinique, sans complication inhabituelle ni réactivation virale, y compris chez 2 patients ayant nécessité une VM.

Discussion

Cette analyse préliminaire suggère que, bien qu’à plus haut risque d’infection sévère, les patients PCNSL infectés par le SARS-CoV-2 devraient être pris en charge de façon maximale, en particulier s’ils sont en réponse oncologique lors de l’infection au SARS-CoV-2. Ces données représentent la première série de PCNSL rapportée et aideront à l’établissement de recommandations internationales pour cette population.

Conclusion

La chimiothérapie pourrait être reprise sans délai prolongé chez les patients suivis pour PCNSL avec COVID-19.

Effectiveness and tolerability of lacosamide as add-on therapy in patients with brain tumor-related epilepsy: Results from a prospective, noninterventional study in European clinical practice (VIBES)

Objective

To evaluate the effectiveness and tolerability of lacosamide added to one or two antiepileptic drugs (AEDs) in the treatment of patients with brain tumor–related epilepsy (BTRE), and to evaluate patients’ global impression of change and quality of life (QoL).

Methods

This was a prospective, multicenter, single‐arm, noninterventional study with a 6‐month observation period (EP0045; NCT02276053). Eligible patients (≥16 years old) had active BTRE secondary to low‐grade glioma (World Health Organization grade 1 and 2) and were receiving treatment with one or two AEDs at baseline. Lacosamide was initiated by the treating physician in the course of routine clinical practice. Primary outcomes were 50% responders (≥50% reduction in focal seizure frequency from baseline) and Patient's Global Impression of Change (PGIC) at month 6. Secondary outcomes included seizure‐free status and Clinical Global Impression of Change (CGIC) at month 6, change in QoL (5‐Level EuroQol‐5 Dimension Quality of Life Assessment) and symptom outcomes (MD Anderson Symptom Inventory–Brain Tumor) from baseline to month 6, and Kaplan‐Meier estimated 6‐month retention on lacosamide. Safety variables included adverse drug reactions (ADRs).

Results

Patients were recruited from 24 sites in Europe. Ninety‐three patients received lacosamide (mean [standard deviation] age = 44.5 [14.7] years; 50 [53.8%] male; median baseline focal seizure frequency = five seizures/28 days [range = 1‐280]), of whom 79 (84.9%) completed the study. At 6 months, 66 of 86 (76.7%) patients were 50% responders and 30 of 86 (34.9%) were seizure‐free. Improvements on PGIC were reported by 49 of 76 (64.5%) patients. Based on CGIC, 52 of 81 (64.2%) patients improved. QoL and symptoms outcome measures remained stable. Kaplan‐Meier estimated 6‐month retention rate was 86.0% (N = 93). Fifteen (16.1%) patients reported ADRs; four (4.3%) had ADRs leading to discontinuation (N = 93).

Significance

Results of this prospective, noninterventional study suggest that add‐on lacosamide is effective and generally well tolerated in patients with BTRE.

Abstract 5705: Mechanisms and therapeutic implications of hypermutation in gliomas

High tumor mutational burden (hypermutation) is observed in some gliomas; however, its mechanisms of development and whether it predicts immunotherapy response are poorly understood. Here, we comprehensively analyze the molecular determinants of mutational burden and signatures in 10,294 gliomas including AACR Project GENIE and institutional datasets. We delineate two main pathways to hypermutation: a de novo pathway associated with constitutional defects in DNA polymerase and mismatch repair (MMR) genes, and a more common post-treatment pathway associated with acquired resistance driven by MMR defects in chemotherapy-sensitive gliomas that recur after temozolomide treatment. Experimentally, the mutational signature of post-treatment hypermutated gliomas was only recapitulated by temozolomide-induced damage in cells harboring MMR deficiency. MMR-deficient gliomas exhibited unique features including the lack of prominent T-cell infiltrates, extensive intratumoral heterogeneity, poor survival and low response rate to PD-1 blockade. Moreover, while microsatellite instability in MMR-deficient gliomas was not detected by bulk analyses, single-cell whole-genome sequencing of post-treatment hypermutated glioma cells demonstrated microsatellite mutations. This study shows that chemotherapy can drive acquisition of hypermutated populations without promoting response to PD-1 blockade and supports diagnostic use of mutational burden and signatures in cancer.

Citation Format: Mehdi Touat, Yvonne Y. Li, Adam N. Boynton, Liam F. Spurr, Bryan Iorgulescu, Craig L. Bohrson, Isidro Cortes-Ciriano, Jack E. Geduldig, Kristine Pelton, Mary J. Lim-Fat, Sangita Pal, Shakti H. Ramkissoon, Frank Dubois, Charlotte Bellamy, Naomi Currimjee, Kenin Qian, Seth Malinowski, Aniket Shetty, Kin-Hoe Chow, Maïté Verreault, Erell Guillerm, Samy Ammari, Frédéric Beuvon, Karima Mokhtari, Agusti Alentorn, Caroline Dehais, Caroline Houillier, Florence Laigle-Donadey, Dimitri Psimaras, Alexandre Carpentier, Philippe Cornu, Laurent Capelle, Bertrand Mathon, Jill S. Barnholtz-Sloan, Arnab Chakravarti, Wenya L. Bi, Garrett M. Frampton, Marc Sanson, Brian M. Alexander, Andrew Cherniack, Patrick Y. Wen, David A. Reardon, Aurelien Marabelle, Peter J. Park, Ahmed Idbaih, Rameen Beroukhim, Pratiti Bandopadhayay, Franck Bielle, Keith L. Ligon. Mechanisms and therapeutic implications of hypermutation in gliomas [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5705.