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Go, Ronald S

0000-0002-8284-3495

Mayo Clinic

Division of Hematology, Mayo Clinic, Rochester, MN.

Citations 59

BRAF testing modalities in histiocytic disorders: Comparative analysis and proposed testing algorithm

American Journal of Clinical Pathology | June 1, 2023 | Volume: 160 | Issue: 5 | Pages: 483-489

10.1093/ajcp/aqad076 | PMID 37458275

Abstract Objectives Understanding of histiocytic disorders has been revolutionized by demonstration of mitogen-activated protein kinase (MAPK) pathway mutations, most commonly BRAFV600E. The optimal testing strategy to assess BRAFV600E is unknown. We aimed to compare performance of testing modalities, to propose a framework for evaluation of BRAFV600E mutation status in histiocytic disorders. Methods We retrospectively reviewed patients with histiocytic disorders and BRAF mutation testing on a lesional tissue specimen. Results In 120 patients, BRAF assessment included immunohistochemistry (IHC) in 97 (80.2%), polymerase chain reaction (PCR) in 35 (28.9%), and next-generation sequencing (NGS) in 62 (51.2%). Forty-five underwent both NGS and IHC. With NGS as the gold standard, the sensitivity and specificity of IHC were 82.4% and 96.4%. Three false negatives were observed in biopsy specimens with low BRAFV600E variant allele frequency or decalcified tissue. One false-positive IHC was observed in a lung biopsy specimen, likely due to antibody cross-reactivity with respiratory cilia. Among 14 with successful NGS and PCR, a single discordance was observed. Two PCR-to-IHC discrepancies were observed, including one other false-positive IHC. Conclusions Immunohistochemistry was highly specific for detection of BRAFV600E. Main caveats were false negatives and lack of detection of non-BRAFV600E mutations. We propose the use of IHC as initial screening in general practice with reflex molecular testing if negative.
The impact of Post-Transplant doxycycline in AL amyloidosis – updated results after Long-Term follow up

Amyloid | December 19, 2022 | Volume: 30 | Issue: 3 | Pages: 261-267

10.1080/13506129.2022.2155809 | PMID 36533960

Insurance-based disparities impact survival outcomes in Waldenström macroglobulinemia within the United States

Leukemia & Lymphoma | July 23, 2022 | Volume: 63 | Issue: 12 | Pages: 2879-2888

10.1080/10428194.2022.2102623 | PMID 35876190

Economic Cost and Sustainability of Oral Therapies in Precision Oncology

JCO Oncology Practice | May 26, 2022 | Volume: 18 | Issue: 8 | Pages: e1247-e1254

10.1200/op.21.00847 | PMID 35617640

PURPOSE: Precision oncology promises improved outcomes but the cost-effectiveness and accessibility of targeted therapies is debatable. We report price change patterns from 2015 to 2019 for several oral anticancer medications for common solid tumor malignancies. METHODS: We collected provider utilization and payment data from the public Medicare Part D database and extracted drug price information for commonly prescribed targeted oral anticancer agents for lung, breast, and prostate cancer. We then calculated median Pearson correlation coefficient values for various drugs (containing more than two data points) within each therapeutic class. We also calculated compound annual growth rates (CAGRs) for medication costs within each class and compared them with the consumer price index (CPI). RESULTS: Our study included six epidermal growth factor receptor inhibitors (EGFRi; one generic), five anaplastic lymphoma kinase inhibitors (ALKi), two B-Raf inhibitors (BRAFi), three hormonal agents (one generic), three cyclin-dependent kinases 4 and 6 inhibitors (CDK4/6i), two poly-ADP-ribose inhibitors (PARPi), and seven antiandrogen agents (two generic). The median (range) Pearson correlation coefficient values for cost of drugs within each therapeutic class were 0.967 (0.915-0.978) for EGFRi, 0.981 (0.966-0.989) for ALKi, 0.996 for BRAFi, 0.994 (0.992-0.999) for CDK4/6i, 0.855 for PARPi, and 0.442 (–0.522 to 0.962) for antiandrogens. Therapies with two or fewer data points (generic erlotinib, dacomitinib, abiraterone, apalutamide, and darolutamide) were excluded. The median CAGRs in costs over the 5-year period were 4.56% (EGFRi), 6.40% (ALKi), 2.58% (BRAFi), 5.48% (hormonal agents), 5.21% (CDK4/6i), 27.29% (PARPi), and 34.8% (antiandrogens). The CPI over 5 years was 2.26%/year, and the average inflation rate was 1.90%/year. CONCLUSION: The median CAGR in costs for modern oral precision-driven cancer therapeutic classes mostly outpaced CPI and the average inflation. Increase in cost within the same class should be weighed against incremental clinical benefit for the patients to ensure that rising costs do not limit access to targeted therapies.
Complement gene variant effect on relapse of complement-mediated thrombotic microangiopathy after eculizumab cessation

Blood Advances | May 9, 2022 | Volume: 7 | Issue: 3 | Pages: 340-350

10.1182/bloodadvances.2021006416 | PMID 35533258

AbstractEculizumab is effective for complement-mediated thrombotic microangiopathy (CM-TMA), also known as atypical hemolytic uremic syndrome. Although lifelong therapy had been suggested, discontinuation does not universally lead to relapse. Comprehensive data evaluating risk factors for recurrence following discontinuation are limited. Our aim was to systematically review available literature assessing the role of complement genetic variants in this setting. Reports on CM-TMA and eculizumab withdrawal published before 1 January 2021, were included. Key reasons for patient exclusion were no follow-up after drug withdrawal and patients lacking complement genetic testing. Two-hundred eighty patients from 40 publications were included. Median age was 28 years, and 25 patients had a known history of renal transplant. Complement genetic variants were identified in 60%, most commonly in CFH (n = 59) and MCP/CD46 (n = 38). Of patients with a complement gene variant, 51.3% had ≥1 likely pathogenic/pathogenic variant whereas the remaining had variants of uncertain significance (VUS). Overall relapse rate after therapy discontinuation was 29.6%. Relapse rate was highest among patients with CFH variants and MCP/CD46 variants in canonical splice regions. VUS (P < .001) and likely pathogenic/pathogenic variants (P < .001) were associated with increased relapse. Presence of a renal allograft (P = .009); decreasing age (P = .029); and detection of variants in CFH (P < .001), MCP/CD46 (P < .001), or C3 (P < .001) were all independently associated with relapse after eculizumab discontinuation. Eculizumab discontinuation is appropriate in specific patients with CM-TMA. Caution should be exerted when attempting such a strategy in patients with high risk of recurrence, including a subgroup of patients with MCP/CD46 variants.
Treatment and outcome of newly diagnosed multiple myeloma patients > 75 years old: a retrospective analysis

Leukemia & Lymphoma | July 15, 2021 | Volume: 62 | Issue: 12 | Pages: 3011-3018

10.1080/10428194.2021.1950708 | PMID 34263694

Teaching NeuroImages: Brain and Skin Involvement in Erdheim-Chester Disease

Neurology | November 10, 2020 | Volume: 96 | Issue: 11 | Pages: No page available

10.1212/wnl.0000000000011159 | PMID 33168700

Treatment facility volume and patient outcomes in Waldenstrom macroglobulinemia

Leukemia & Lymphoma | October 15, 2020 | Volume: 62 | Issue: 2 | Pages: 308-315

10.1080/10428194.2020.1832669 | PMID 33054437

Financial conflicts of interest among National Comprehensive Cancer Network clinical practice guideline panelists in 2019

Cancer | June 4, 2020 | Volume: 126 | Issue: 16 | Pages: 3742-3749

10.1002/cncr.32997 | PMID 32497271

Background Clinical practice guidelines (CPGs) are evidence‐based guidelines that serve as a standard of care in oncology practice, reimbursements, and quality improvement initiatives. To our knowledge, the extent of financial conflicts of interest (FCOIs) in National Comprehensive Cancer Network (NCCN) guidelines have not been systemically evaluated. The current study evaluated the extent of FCOIs in the NCCN CPGs for the most common malignancies in the United States. Methods The authors examined the latest 2019 versions of the NCCN CPGs for the 10 most common cancers by incidence in the United States. Using disclosure lists, they catalogued the FCOIs for the panelists under various categories outlined in the CPG. The authors also tabulated the companies and institutions involved in each panel disclosure. An “episode” describes 1 instance of participation of a panelist in 1 company in 1 category of each guideline. “Affiliation” describes an industrial, commercial, or institutional affiliation reported by a panelist in each episode. Results Of the 491 panelists on the CPG panel, 483 (98.3%) completed FCOI disclosures. A total of 224 (46.4%) reported at least 1 FCOI episode. A total of 1103 episodes were disclosed with an average of 4.9 episodes reported per panelist with FCOIs. Acting as part of scientific advisory boards, as a consultant, or as an expert witness was the most common FCOI category (19.9%). A total of 191 companies were associated with 1103 episodes of FCOI. The top companies were Bristol‐Myers Squibb, Merck, Genentech, and AstraZeneca. Among cancers, the prevalence of FCOIs was highest for lung cancer (56%), bladder cancer (52%), pancreatic cancer (52%), non‐Hodgkin lymphoma (50%), kidney cancer (49%), colorectal cancer (43%), breast cancer (42%), melanoma (40%), prostate cancer (38%), and uterine cancer (32%). Among the panelists with FCOIs, 26%, 17%, and 57%, respectively, reported 1, 2, and >3 episodes. There were 127 episodes noted among the CPG chairs and/or vice chairs who reported FCOIs (mean, 6.4 episodes). The chairs and/or vice chairs of CPGs for uterine cancer, pancreatic cancer, melanoma, and prostate cancer were not found to have any FCOIs. Conclusions FCOIs are very prevalent among NCCN CPG panelists. In nearly one‐half of the CPGs, the majority of the panelists had at least 1 FCOI. Greater than one‐half of the CPG chairs and/or vice chairs reported multiple FCOIs. Further research studies are necessary to determine the impact of these FCOIs.
Development of thrombocytopenia during first-line treatment and survival outcomes in newly diagnosed multiple myeloma

Leukemia & Lymphoma | May 17, 2019 | Volume: 60 | Issue: 12 | Pages: 2960-2967

10.1080/10428194.2019.1613536 | PMID 31096812