MLTI-08. AN EXCEPTIONAL INTRACRANIAL RESPONSE TO REPEAT RADIATION AND IMMUNOTHERAPY IN A PATIENT WITH METASTATIC, POORLY DIFFERENTIATED ADENOCARCINOMA OF THE LUNG

We report an unusual case of a long-term survivor of metastatic, poorly differentiated adenocarcinoma of the lung (EGFR- ALK-) who developed intracranial disease after definitive treatment of a stage IIIB lung cancer. He received a complex course of RT which began with SRS to his intracranial disease in 2012 and included: brainstem (pontine) mass, left parietal mass, left frontal, left lateral temporal, and left insular lesions. The left temporal mass progressed and was resected. Subsequently, SRS was given to a right anterior frontal lesion. Additional SRS was given to progressive right superior frontal mass & left temporal tumor bed was given fractionated RT to the left temporal tumor bed. Later, he developed bilateral cerebellar masses and right-sided progression. More SRS was given to right frontal area, and then to bilateral cerebellar lesions. Surprisingly, he did well neurologically until seizures developed. His repeat biopsy was sent for NGS and noted to be PDL1+, APC mutated, and KRAS mutated. This gentleman was started on pembrolizumab in May 2016. Due to colitis, his therapy stopped in January 2017. His colitis progressed such that immunotherapy could not be restarted. Now, after observation only for the past 2.5 years. his disease has disappeared. He is doing well neurologically. We propose that the use of radiation and immunotherapy worked to produce an exceptional, durable response.

RADI-16. ECONOMIC IMPLICATIONS OF PREOPERATIVE VERSUS POSTOPERATIVE STEREOTACTIC RADIOSURGERY FOR BRAIN METASTASES

OBJECTIVE: Retrospective data suggests preoperative stereotactic radiosurgery (preSRS) reduces radiation necrosis (RN) and leptomeningeal disease (LMD) failure after resection of brain metastases (BM) as compared to postoperative SRS (postSRS). We evaluated the potential financial impact of a reduction in symptomatic RN (SRN) and LMD, should preSRS become a national standard. METHODS: A decision tree was designed to evaluate the two strategies: preSRS vs. postSRS. We assumed no difference in survival and that a reduction in SRN and LMD exists on par with retrospective data. Effectiveness was not considered given unclear health utilities. Treatments for SRN considered were dexamethasone, bevacizumab, surgical resection, or hyperbaric oxygen (HBO). Treatments for LMD considered included conventional radiation, SRS, systemic therapy (lapatinib/capecitabine), or no therapy. Probabilities were extracted from the 2-year LMD/SRN rates and subsequent treatment patterns observed in retrospective data. Treatment costs were based on the 2019 Medicare physician fee schedule and published data in 2019 US dollars without discounting. National costs to the healthcare system were estimated by assuming 200,000 BM cases per year with a surgical utilization rate of 16%. Deterministic and probabilistic sensitivity analyses (PSA) were performed. RESULTS: The incorporated rate of LMD and SRN for postSRS was 22.4% and 16.4% and 4.3% and 4.9% for preSRS, respectively. The expected mean costs were $3,129 for postSRS and $810 for preSRS. Deterministic sensitivity analysis demonstrated that the model was sensitive to only LMD/SRN rates. PSA demonstrated that in 95% of simulations, the expected savings ranged from $770-$6,429/patient. Therefore, the national healthcare system stands to save approximately $74 million per year if preSRS was a national standard (range $25–206 million). CONCLUSIONS: A prospective randomized trial demonstrating the effectiveness of preSRS in the reduction of LMD and/or SRN would carry a significant return on investment through the reduction of subsequent treatment costs.

Single agent ONC201 in adult recurrent H3 K27M-mutant glioma

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Background: H3 K27M-mutant glioma is associated with a poor prognosis and there is no effective therapy following radiation. We report the clinical experience with single agent ONC201, the first small molecule DRD2 antagonist in oncology, in adults with recurrent H3 K27M-mutant glioma. Methods: Twenty-nine adult patients with recurrent H3 K27M-mutant glioma have been treated with single agent ONC201 as of January 20, 2019: 19 patients on NCT03295396; 8 patients on NCT02525692; 2 patients on compassionate use protocols under the Sponsor’s IND. Median age was 57 years old (range: 17-74), median prior lines of therapy was 2 (range: 1-4) and all patients received prior radiation (median 8.5 months from radiation completion to ONC201 initiation). ONC201 was orally administered at 625 mg weekly, except for one patient dosed once every 3 weeks. Results: As of February 5, 2019, 13 of 29 patients remain on-trial within median follow up of 6.5 months (range: 0.6-33.6), 8 patients are alive but off-trial with median follow up of 2.4 months (range: 0.2-9), and 8 patients have expired. Nine of 29 patients (31%) remain progression-free on ONC201 with a median follow up of 6.5 months (range 0.6-33.6). No dose-limiting toxicities or treatment discontinuations due to toxicity occurred. Three patients have experienced durable partial responses by RANO (4.3-28.5 months). In addition, one patient experienced complete regression that continues for > 14 months of all < 1 cm tumor lesions that are not measurable by RANO. Furthermore, 10 patients had a best response of stable disease by RANO, 12 patients experienced progressive disease, and 3 patients are not yet evaluable. Among the patients with a best response of stable disease by RANO, one patient had > 50% tumor regression in the basal ganglia that did not qualify as a partial response by RANO due to a new lesion on a confirmatory scan. Another patient with stable disease by RANO has had 37% tumor regression so far in the brainstem and remains on-treatment for 6 months. All tumor regressions remain durable to date and some were associated with improvements in disease-associated neurological symptoms. Conclusions: Single agent ONC201 is well tolerated and clinically active in adult recurrent H3 K27M-mutant glioma patients. Clinical trial information: NCT03295396; NCT02525692.

Anticonvulsant Prophylaxis and Steroid Use in Adults With Metastatic Brain Tumors: ASCO and SNO Endorsement of the Congress of Neurological Surgeons Guidelines

PURPOSE

The Congress of Neurological Surgeons (CNS) has developed a series of guidelines for the treatment of adults with metastatic brain tumors, including systemic therapy and supportive care topics. ASCO has a policy and set of procedures for endorsing clinical practice guidelines that have been developed by other professional organizations.

METHODS

Two CNS guidelines were reviewed for developmental rigor by methodologists, and an independent multidisciplinary Expert Panel was formed to review the content and assess agreement with the recommendations. The Expert Panel voted to endorse the two guidelines, and ASCO and Society for Neuro-Oncology (SNO) independently reviewed and approved the ASCO/SNO guideline endorsement.

RESULTS

The ASCO/SNO Expert Panel determined that the recommendations from the CNS anticonvulsants and steroids guidelines, published January 9, 2019, are clear, thorough, and based on the most relevant scientific evidence. ASCO/SNO endorsed these two CNS guidelines with minor alterations.

RECOMMENDATIONS

Key recommendations include the following: prophylactic antiepileptic drugs were not recommended for routine use; and corticosteroids, specifically dexamethasone, were recommended for temporary symptomatic relief in patients with neurologic symptoms and signs related to mass effect from brain metastases. Additional information is available at www.asco.org/neurooncology-guidelines .

Comparing pre-operative stereotactic radiosurgery (SRS) to post-operative whole brain radiation therapy (WBRT) for resectable brain metastases: a multi-institutional analysis

Pre-operative stereotactic radiosurgery (pre-SRS) has been shown as a viable treatment option for resectable brain metastases (BM). The aim of this study is to compare oncologic outcomes and toxicities for pre-SRS and post-operative WBRT (post-WBRT) for resectable BM. We reviewed records of consecutive patients who underwent resection of BM and either pre-SRS or post-WBRT between 2005 and 2013 at two institutions. Overall survival (OS) was calculated using the Kaplan-Meier method. Cumulative incidence was used for intracranial outcomes. Multivariate analysis (MVA) was performed using the Cox and Fine and Gray models, respectively. Overall, 102 patients underwent surgical resection of BM; 66 patients with 71 lesions received pre-SRS while 36 patients with 42 cavities received post-WBRT. Baseline characteristics were similar except for the pre-SRS cohort having more single lesions (65.2% vs. 38.9%, p = 0.001) and smaller median lesion volume (8.3 cc vs. 15.3 cc, p = 0.006). 1-year OS was similar between cohorts (58% vs. 56%, respectively) (p = 0.43). Intracranial outcomes were also similar (2-year outcomes, pre-SRS vs. post-WBRT): local recurrence: 24.5% vs. 25% (p = 0.81), distant brain failure (DBF): 53.2% vs. 45% (p = 0.66), and leptomeningeal disease (LMD) recurrence: 3.5% vs. 9.0% (p = 0.66). On MVA, radiation cohort was not independently associated with OS or any intracranial outcome. Crude rates of symptomatic radiation necrosis were 5.6 and 0%, respectively. OS and intracranial outcomes were similar for patients treated with pre-SRS or post-WBRT for resected BM. Pre-SRS is a viable alternative to post-WBRT for resected BM. Further confirmatory studies with neuro-cognitive outcomes comparing these two treatment paradigms are needed.

Outcome after bevacizumab clinical trial therapy among recurrent grade III malignant glioma patients

Although outcome following bevacizumab among recurrent grade IV malignant glioma patients is documented as poor by several analyses, outcome for recurrent grade III patients following bevacizumab therapy has not been specifically evaluated. We performed a pooled analysis of 96 recurrent grade III malignant glioma patients enrolled on three consecutive phase II bevacizumab salvage trials to evaluate overall outcome following bevacizumab trial discontinuation. Outcome on the three bevacizumab trials, which included similar eligibility, treatment and assessment criteria, was comparable. Forty-nine patients who progressed on bevacizumab trial therapy and remained alive for at least 30 days elected to receive additional therapy. These patients achieved a median PFS-6 and OS of 30.6% (95% CI: 18.4, 43.6) and 10.3 months (95% CI: 5.2, 11.7), respectively. Among patients who continued bevacizumab therapy (n = 23) after study progression, PFS-6 and median OS were 39.1% (95% CI: 19.9, 58.0) and 9.2 months (95% CI: 5.2, 13.6), respectively, compared to 23.1% (95% CI: 9.4, 40.3; P = 0.51) and 10.3 months (95% CI: 2.5, 14.4; P = 0.91) for patients who initiated non-bevacizumab containing therapy (n = 26). Outcome after discontinuation of bevacizumab therapy for recurrent grade III malignant glioma patients is associated with improved outcome compared to historical data for recurrent grade IV malignant glioma patients. Salvage therapies following bevacizumab failure have modest activity for grade III malignant glioma patients that is independent of further bevacizumab continuation.

Recurrent, transformed non-Hodgkin's lymphoma presenting as chiasmal syndrome with hyperprolactinemia and hypopituitarism

A 69-year-old white female with past medical history of follicular cell lymphoma presented to her local physician with new neurological findings. She was subsequently diagnosed with a pituitary lesion comprised of diffuse large B cell lymphoma. Non-Hodgkin's lymphoma (NHL) affecting the pituitary uncommonly appears as metastatic disease from a concurrent systemic lymphoma. This case represents the first case of recurrent, transformed NHL as chiasmal syndrome with hyperprolactinemia and hypopituitarism in the American medical literature.

Pneumococcal septic arthritis as the initial presentation of multiple myeloma

Septic arthritis induced by Streptococcus pneumoniae is an uncommon manifestation of pneumococcal infection. Pneumococcus has been identified as the inciting pathogen in only 6% of cases of septic arthritis in recent retrospective studies (Ross et al., 2003). Approximately 50% of patients with pneumococcal septic arthritis have a preceding or concurrent extra-articular focus of infection. The septic joint evolves from hematogenous seeding of the highly vascular synovial membrane by bacteria. Polyarticular disease occurs in only approximately 36% of patients. Most pneumococcal septic arthritis occurs with coexistant joint disease, prosthesis, alcoholism, HIV infection, or rheumatoid arthritis (Baraboutis & Skoutelis, 2004; Raad & Peacock, 2004). We report a case of polyarticular septic arthritis as the first manifestation of an underlying disease. Our literature review discloses that this is the first reported case of multiple myeloma initially presenting as pneumococcal septic arthritis in the USA and the third internationally (Cuesta et al., 1992; Renou et al., 2007).

A case of severe hemorrhagic diarrhea

A 50-year-old white female presented to the emergency department with diarrhea, abdominal pain, and hematochezia. The illness started four days prior to presentation and escalated to 10-15 bowel movements daily. She was tachycardic and hypotensive upon presentation with a diffusely tender abdomen. Her anemia and persistent hematochezia prompted endoscopy by a gastroenterologist. Flexible sigmoidoscopy was performed to the splenic flexure and revealed evidence of severe active colitis. The mucosa was friable and severely ulcerated. Numerous biopsies were obtained that revealed acute colitis with fibrinopurulent exudates. A stool culture showed Escherichia coli O157:H7, which was confirmed by the Mississippi State Board of Health. Infection with E. coli O157:H7 affects nearly 1.1 per 100,000 Americans annually. It accounts for about 3% of all bacterial and protozoal causes of foodborne illnesses and possesses a mortality rate of about 1-2%.

Therapy-related acute nonlymphoblastic leukemia following mitoxantrone therapy in a patient with multiple sclerosis

A 58-year-old male with migraine headaches, complex partial epilepsy, and secondary progressive multiple sclerosis treated with mitoxantrone was admitted to our facility in August 2005 with febrile neutropenia, worsening ataxia, aphasia, cough, and declining mental status. Bone marrow aspirate was consistent with acute nonlymphoblastic leukemia. Review of the literature reveals ten reported cases of nonlymphoblastic leukemias following treatment with mitoxantrone. Although de novo leukemia cannot be fully excluded, the likelihood of de novo disease is low given the patient's medical history. This case continues the important discussion of efficacy versus toxicity when selecting mitoxantrone as a therapeutic option for patients with multiple sclerosis. Although leukemia is rarely seen, the potential for this outcome warrants careful consideration before initiating this therapy.