Citations

Stem cell treatment outside of studied and approved medical indications can have unforeseen adverse consequences. Here, we present a 74-year-old male that underwent such therapy. The patient presented to our institution with progressive lower extremity weakness and urinary incontinence. He had previously undergone intrathecal stem cell therapy in Moscow, Russia for weakness and fatigue. Magnetic resonance imaging of his thoracic and lumbar spine showed marked enlargement of the cauda equina nerve roots and abnormal mass-like soft tissue involving the thoracolumbar thecal sac. Surgical biopsy of the intrathecal soft tissue showed polyclonal lymphocytic and glial cell proliferation. The patient’s symptoms did not improve with medical treatment or radiation, and he is currently under observation after multidisciplinary evaluation. Our patient’s experience illustrates one of the potential risks of “stem cell tourism” and exemplifies the imaging and histopathologic features of this rare entity. We also compare our patient’s treatment with other similar examples of stem cell treatments in our institution and others. These have had a wide spectrum of results. In some instances, intrathecal stem cells have caused abnormal imaging findings without any associated patient symptoms. In extreme examples, however, stem cell treatments have resulted in central nervous system neoplasms. Our patient’s lesion is quite unique, with only one similar lesion having been previously published.

Abstract Introduction: Outcomes of multidisciplinary and molecular tumor boards have been reported. Lymphoma specific tumor board outcomes have not been reported in the molecular era. In addition, the utility of multi-site, interactive tumor boards using videoconference technology are not widely reported. We prospectively followed the outcomes of a multidisciplinary multi-site lymphoma tumor board in the molecular era and during a change in the revision of the World Health Organization Classification in first published in 2016. Methods: The Mayo Clinic Lymphoma Tumor Board is a component of the international Mayo Clinic Care Network (MCCN). The format includes the clinical case presentation, presentation of radiology and hematopathology findings by the appropriate specialist, proposed treatment options, review of the literature pertinent to the case, and discussion followed by recommendations. Requirement for presentation includes having a diagnosis of lymphoma with pathology reviewed at Mayo Clinic, Rochester, MN (MCR). Pathology and radiology material, when relevant to the case, are required to be reviewed at MCR and presented by MCR pathologists/radiologists. Patients must be presented prospectively, and have active clinical issues or questions to be addressed. Four cases are presented per 60-minute meeting. 309 consecutive highly selected cases with a diagnosis of lymphoma were presented at the Mayo Clinic Lymphoma Tumor Board from 2014 to 2018. The pathology material was independently reviewed by the presenting hematopathologists and radiology material by the presenting radiologist. Participants are office based and included multiple members of the health care team which also incudes pharmacists, clinical research associates affiliated with lymphoma research, and physicians in training. Recommendations were prospectively tracked for changes in radiology interpretation, pathologic diagnosis, and treatment approaches. Actual follow-up of all patients after the meeting was not allowed in the MCCN. Participation in the meeting can be either via in-room attendance at MCR, video conference at a participating MCCN site, or via non-participatory live-stream online. Results: 309 cases were presented were presented from 2014-2018. 258 cases were from MCR, and 51 were not physically seen at MCR. 16 cases were presented at a subsequent meeting for further recommendations in the course of their disease after the initial presentation. 54% of patients presented had changes in some aspect of their care as a result of the meeting. Changes in radiologic interpretation occurred in 5 (1.6%) patients. The pathologic diagnosis changed in 27 (8.7%). Additional testing was recommended in 44 (14%). Clinical management changes were recommended in 90 (29%) cases. These included alterations in treatment approach in 43 (14%), change from undecided to pursuit of treatment 10 (3%), change from undecided regarding treatment approach to further diagnostic testing 4 (1.3%), change from observation to treatment 9 (3%), change from treatment to observation 4 (1.3%), and treatment to further tests in 2 (0.6%) Site in room average attendance (internal/external) was 16.8/8.6. Non-participatory live-stream attendance was not possible to track. In an annual electronic evaluation of this activity, 93% of the responders reported an improvement in knowledge and competence, and 100% recommended no changes to the format of the conference. Enhancements over time have included Continuous Medical Education credit, an in room microscope, and real-time radiology images. Selected cases will now be on line on an international web site. Conclusion: In this highly selected group of lymphoma cases from multiple sites over a 4-year period, 54% of the (167/309) case presentations resulted in changes to some aspect of care as a direct result of this tumor board. A multidisciplinary lymphoma tumor board approach was of value, efficacious, and meaningfully impacted lymphoma patients while substantially enhancing interdisciplinary interactions. Disclosures Ansell: Celldex: Research Funding; Seattle Genetics: Research Funding; Takeda: Research Funding; Bristol-Myers Squibb: Research Funding; Pfizer: Research Funding; Merck & Co: Research Funding; LAM Therapeutics: Research Funding; Regeneron: Research Funding; Trillium: Research Funding; Affimed: Research Funding.

Introduction: Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is a multisystemic mitochondrial disorder that usually presents in childhood. Patients can have a wide array of neurological symptoms when presenting with stroke-like episodes, and imaging characteristics during the episodes can overlap with different neurological disorders. Case Report: A 61-year-old woman presented with communication difficulties consistent with auditory agnosia and was found to have bitemporal abnormalities on imaging that first raised the concern for herpes simplex virus encephalitis. Further work-up, in conjunction with the patient’s past medical and family history, suggested a mitochondrial disorder. Mitochondrial full genome analysis revealed m.3243A>G variant in the MT-TL1 gene, with 6% heteroplasmy in blood leading to a diagnosis of MELAS. Conclusions: MELAS is a disorder with clinical variability. Neuroimaging studies during stroke-like episodes in MELAS can provide significant clues to the underlying disorder. Although patients typically present in childhood, the first stroke-like episode can occur later in life in some patients, potentially related to a lower heteroplasmy level.

Background: Gadolinium-enhanced T1-weighted magnetic resonance imaging (MRI) (T1WI) is the conventional imaging technique of choice to detect vestibular schwannoma (VS) recurrence or regrowth, despite suboptimal specificity secondary to enhancing postoperative changes. Furthermore, recent concerns regarding the accumulation of gadolinium in body tissues have led for a call to reduce the number of contrast-enhanced examinations. The objective of the current study is to evaluate the diagnostic accuracy of high-resolution noncontrast (three-dimensional [3D] T2) MRI relative to gadolinium-enhanced T1WI in the detection of VS recurrence after resection. Methods: Following Institutional Review Board approval, 13 consecutive postoperative patients with VS recurrence or regrowth were identified from a prospectively maintained clinical database in which recurrence was determined by progression on serial postoperative MRI examination. Three blinded neuroradiologists retrospectively evaluated a total of 41 postoperative MRI examinations from these patients using only gadolinium-enhanced T1WI and 3D T2 MRI for recurrence or regrowth. Interobserver agreement, differences in detection between the two sequences, and the sensitivity and specificity of 3D T2 MRI were assessed. Results: Fifteen of the 41 postoperative MRIs demonstrated progression, as determined by examiner consensus on the gadolinium-enhanced T1WI. Agreement, measured using Krippendorff's alpha, was 0.82 for the 3D T2 images and 0.83 for the contrast-enhanced T1WI. All the three examiners demonstrated no difference in the detection of progression between the two sequences (McNemar's test p values 0.69 for examiner 1, 0.63 for examiner 2, and 0.99 for examiner 3). The sensitivity of 3D T2 was 0.78 (CI 0.60–0.96), while the specificity was 0.94 (CI 0.86–1.00). Conclusion: Noncontrast high-resolution 3D T2 MRI seems sufficient to assess for recurrence or regrowth after VS resection. The results of this study have implications for reducing cost, time, and adverse events associated with gadolinium administration in this population requiring serial follow-up examinations. These promising, yet preliminary findings warrant confirmation with a larger prospective cohort of patients.