Molecular Advances in the Treatment of Advanced Gastrointestinal Stromal Tumor.

Most gastrointestinal stromal tumors (GIST) are driven by activating mutations in Proto-oncogene c-KIT (KIT) or PDGFRA receptor tyrosine kinases (RTK). The emergence of effective therapies targeting these mutations has revolutionized the management of advanced GIST. However, following initiation of first-line imatinib, a tyrosine kinase inhibitor (TKI), nearly all patients will develop resistance within 2 years through the emergence of secondary resistance mutations in KIT, typically in the Adenosine Triphosphate (ATP)-binding site or activation loop of the kinase domain. Moreover, some patients have de novo resistance to imatinib, such as those with mutations in PDGFRA exon 18 or those without KIT or PDGFRA mutation. To target resistance, research efforts are primarily focused on developing next-generation inhibitors of KIT and/or PDGFRA, which can inhibit alternate receptor conformations or unique mutations, and compounds that impact complimentary pathogenic processes or epigenetic events. Here, we review the literature on the medical management of high-risk localized and advanced GIST and provide an update on clinical trial approaches to this disease.

Incidence of bleeding events in patients on concomitant tyrosine kinase inhibitors and selective serotonin reuptake inhibitors.

INTRODUCTION: In this study, we aim to determine the risk of bleeding or thrombosis with concurrent use of tyrosine kinase inhibitors (TKIs) used to treat CML, and serotonin reuptake inhibitors (SSRIs). METHODS: We conducted a retrospective cohort study of patients with CP-CML cared for at Massachusetts General Hospital (MGH) between April 2016 to February 2021. Participants were included if diagnosed with CP-CML and began TKI treatment (imatinib, dasatinib, nilotinib, bosutinib, or ponatinib) after April 2016. RESULTS: One hundred patients were evaluated, eighty of whom were taking TKIs only (median age 55, 40% female), and twenty were taking TKI and SSRI concomitantly (median age 53.5, 55% female). Baseline demographics between these groups were similar across all variables. Patients in the TKI only group had 9 bleeding events and 3 thrombotic events. Patients in the combination group had 6 bleeding events and 1 thrombotic event. There was no difference between overall rates of major bleeding (4% v. 10%, p = 0.26) or thrombotic events (4% v. 5%, p = 1). However, patients in the combination group were more likely to have major intracranial bleeding events (0% v. 10%, p = 0.04), and there was a trend to significance for minor bleeding events (7.5% v. 20%, p = 0.11). CONCLUSIONS: Concomitant use of TKIs and SSRIs does not appear to increase the total risk of bleeding or thrombotic events compared to patients on TKIs only. However, concomitant use of TKIs and SSRIs may increase risk of intracranial bleeding. Further work is needed to fully assess this risk.

Histiocytic and Dendritic Cell Sarcomas of Hematopoietic Origin Share Targetable Genomic Alterations Distinct from Follicular Dendritic Cell Sarcoma.

BACKGROUND: Histiocytic and dendritic cell neoplasms are a diverse group of tumors arising from monocytic or dendritic cell lineage. Whereas the genomic features for Langerhans cell histiocytosis and Erdheim-Chester disease have been well described, other less common and often aggressive tumors in this broad category remain poorly characterized, and comparison studies across the World Health Organization diagnostic categories are lacking. METHODS: Tumor samples from a total of 102 patient cases within four major subtypes of malignant histiocytic and dendritic cell neoplasms, including 44 follicular dendritic cell sarcomas (FDCSs), 41 histiocytic sarcomas (HSs), 7 interdigitating dendritic cell sarcomas (IDCSs), and 10 Langerhans cell sarcomas (LCSs), underwent hybridization capture with analysis of up to 406 cancer-related genes. RESULTS: Among the entire cohort of 102 patients, CDKN2A mutations were most frequent across subtypes and made up 32% of cases, followed by TP53 mutations (22%). Mitogen-activated protein kinase (MAPK) pathway mutations were present and enriched among the malignant histiocytosis (M) group (HS, IDCS, and LCS) but absent in FDCS (72% vs. 0%; p < .0001). In contrast, NF-κB pathway mutations were frequent in FDCSs but rare in M group histiocytoses (61% vs. 12%; p < .0001). Tumor mutational burden was significantly higher in M group histiocytoses as compared with FDCSs (median 4.0/Mb vs. 2.4/Mb; p = .012). We also describe a pediatric patient with recurrent secondary histiocytic sarcoma treated with targeted therapy and interrogated by molecular analysis to identify mechanisms of therapeutic resistance. CONCLUSION: A total of 42 patient tumors (41%) harbored pathogenic mutations that were potentially targetable by approved and/or investigative therapies. Our findings highlight the potential value of molecular testing to enable precise tumor classification, identify candidate oncogenic drivers, and define personalized therapeutic options for patients with these aggressive tumors. IMPLICATIONS FOR PRACTICE: This study presents comprehensive genomic profiling results on 102 patient cases within four major subtypes of malignant histiocytic and dendritic cell neoplasms, including 44 follicular dendritic cell sarcomas (FDCSs), 41 histiocytic sarcomas (HSs), 7 interdigitating dendritic cell sarcomas (IDCSs), and 10 Langerhans cell sarcomas (LCSs). MAPK pathway mutations were present and enriched among the malignant histiocytosis (M) group (HS, IDCS, and LCS) but absent in FDCSs. In contrast, NF-κB pathway mutations were frequent in FDCSs but rare in M group histiocytosis. A total of 42 patient tumors (41%) harbored pathogenic mutations that were potentially targetable by approved and/or investigative therapies.

Setting Intentions.

In this narrative medicine essay, an oncologist ruminates over a chemotherapy consent form about the goals of therapy for a young adult whose body is filled with an aggressive cancer most commonly seen in children.

Safety and Efficacy of the Combination Lurbinectedin plus Doxorubicin from a Phase 1b Trial in Patients with Advanced/Metastatic Soft-Tissue Sarcoma.

PURPOSE: While cytotoxic chemotherapy is the standard first-line treatment for patients with metastatic soft-tissue sarcoma (STS), clinical outcomes remain suboptimal. Our prior study showed lurbinectedin plus doxorubicin is well tolerated with promising clinical activity in STS. We designed this phase 1b trial to optimize dosing as the basis for a randomized trial in leiomyosarcoma and to further explore the safety profile and efficacy signal. PATIENTS AND METHODS: Patients had advanced/metastatic STS and no prior anthracycline/lurbinectedin/trabectedin. Escalation followed a 3 + 3 design with 3-week cycles: lurbinectedin (3.2 mg/m2 day 1) and two doxorubicin levels (DL1, 25 mg/m2 day 1; DL2, 25 mg/m2 days 1 and 8). The primary objectives were to identify the maximum tolerated dose and recommended dose for subsequent randomized trials. RESULTS: Ten patients were enrolled in a 6-month period. The most common treatment-emergent adverse events were grade (G) 2 fatigue and nausea, and G2 cytopenias with no febrile neutropenia events. There were two dose-limiting toxicities (DLTs) at DL2 [day 8 (G2 alanine aminotransferase [ALT]/aspartate aminotransferase increase, G3 neutropenia)], and one DLT in DL1 (G3 ALT increase). These were reversible and all patients continued the study. DL1 was chosen for further study. At the time of data cutoff, the estimated median progression-free survival is 16.5 months [95% confidence interval (CI), 6.0-ND]. The objective response rate was 60% (6/10 confirmed partial responses). CONCLUSIONS: In this phase 1b study, the recommended dose is lurbinectedin 3.2 mg/m2 in combination with doxorubicin 25 mg/m2 every 3 weeks. The study combination was well tolerated and demonstrated intriguing clinical activity.

Blast and accelerated phase CML: room for improvement.

Tyrosine kinase inhibitors (TKIs) revolutionized the treatment of chronic myeloid leukemia (CML). With TKI therapy, the percentage of patients who progress to accelerated phase (AP) or blast phase (BP) CML has decreased from more than 20% to 1% to 1.5% per year. Although AP- and BP-CML occur in a minority of patients, outcomes in these patients are significantly worse compared with chronic phase CML, with decreased response rates and duration of response to TKI. Despite this, TKIs have improved outcomes in advanced phase CML, particularly in de novo AP patients, but are often inadequate for lasting remissions. The goal of initial therapy in advanced CML is a return to a chronic phase followed by consideration for bone marrow transplantation. The addition of induction chemotherapy with TKI is often necessary for achievement of a second chronic phase. Given the small population of patients with advanced CML, development of novel treatment strategies and investigational agents is challenging, although clinical trial participation is encouraged in AP and BP patients, whenever possible. We review the overall management approach to advanced CML, including TKI selection, combination therapy, consideration of transplant, and novel agents.

Arsenic toxicity manifesting as profuse watery diarrhea during induction therapy for acute promyelocytic leukemia.

Arsenic trioxide (ATO) is generally well tolerated for treatment of APL. We present a patient with severe watery diarrhea and pancreatitis thought to be due to ATO toxicity in the setting of obesity and acute kidney injury. Future studies evaluating ATO levels in patients experiencing toxicities may help guide dose modifications.

Irritable bowel syndrome leading to scurvy from a severely restricted diet.

A 69-year-old man with irritable bowel syndrome on a restricted diet presented with fatigue, myalgias, extensive bilateral lower-extremity petechiae and ecchymoses, transfusion-refractory anemia, and elevated inflammatory markers. A low serum vitamin C level led to the diagnosis of scurvy. This is the first reported case of vitamin C deficiency and clinical scurvy related to voluntary dietary restriction from irritable bowel syndrome in an adult patient.

Novel methods and technologies for 21st-century clinical trials: a review.

IMPORTANCE: New technologies are rapidly reshaping health care. However, their effect on drug development to date generally has been limited. OBJECTIVES: To evaluate disease modeling and simulation, alternative study design, novel objective measures, virtual research visits, and enhanced participant engagement and to examine their potential effects as methods and tools on clinical trials. EVIDENCE REVIEW: We conducted a systematic search of relevant terms on PubMed (disease modeling and clinical trials; adaptive design, clinical trials, and neurology; Internet, clinical trials, and neurology; and telemedicine, clinical trials, and neurology), references of previous publications, and our files. The search encompassed articles published from January 1, 2000, through November 30, 2014, and produced 7976 articles, of which 22 were determined to be relevant and are included in this review. FINDINGS: Few of these new methods and technologies have been applied to neurology clinical trials. Clinical outcomes, including cognitive and stroke outcomes, increasingly are captured remotely. Other therapeutic areas have successfully implemented many of these tools and technologies, including web-enabled clinical trials. CONCLUSIONS AND RELEVANCE: Increased use of new tools and approaches in future clinical trials can enhance the design, improve the assessment, and engage participants in the evaluation of novel therapies for neurologic disorders.

Impact of alternative medical device approval processes on costs and health.

BACKGROUND: Medical devices are often introduced prior to randomized-trial evidence of efficacy and this slows completion of trials. Alternative regulatory approaches include restricting device use outside of trials prior to trial evidence of efficacy (like the drug approval process) or restricting out-of-trial use but permitting coverage within trials such as Medicare's Coverage with Study Participation (CSP). METHODS: We compared the financial impact to manufacturers and insurers of three regulatory alternatives: (1) limited regulation (current approach), (2) CSP, and (3) restrictive regulation (like the current drug approval process). Using data for patent foramen ovale closure devices, we modeled key parameters including recruitment time, probability of device efficacy, market adoption, and device cost/price to calculate profits to manufacturers, costs to insurers, and overall societal impact on health. RESULTS: For manufacturers, profits were greatest under CSP-driven by faster market adoption of effective devices-followed by restrictive regulation. Societal health benefit in total quality-adjusted life years was greatest under CSP. Insurers' expenditures for ineffective devices were greatest with limited regulation. Findings were robust over a reasonable range of probabilities of trial success. CONCLUSIONS: Regulation restricting out-of-trial device use and extending limited insurance coverage to clinical trial participants may balance manufacturer and societal interests.

Virtual visits for Parkinson disease: A case series.

We sought to characterize recommendations and feedback of patients with Parkinson disease, each offered a free telemedicine consultation with a specialist. Visits consisted of history, neurologic examination, and recommendations. Midway through the program, patients were asked to complete an online satisfaction survey. From August 2012 to May 2013, 55 patients in 5 states (mean age 67.8 years) participated, with 80% of visits conducted from their home. Patients with Parkinson disease were recommended to exercise (86%), change current medication (63%), and add new medication (53%). Thirty-three of 35 consecutive patients completed a survey. Patient satisfaction exceeded 90% for virtually all aspects of the visit measured. Providing care to patients in their homes via telemedicine is feasible, results in changes to care, and is well-received.

A pilot study of virtual visits in Huntington disease.

BACKGROUND: Virtual visits through web-based video conferencing can increase access to specialty care for individuals with Huntington disease (HD) and facilitate research participation. OBJECTIVE: To determine the feasibility of conducting virtual visits directly into the homes of individuals with HD, to assess the reliability of conducting remote versus in-person motor assessments, and to determine the test-retest reliability of conducting motor assessments remotely. METHODS: Individuals with mild to moderate HD underwent baseline in-person clinic assessments and completed a HD care survey. Participants were randomized to receive three virtual visits from one of two physicians over four months that included a modified Unified Huntington's Disease Rating Scale motor examination (excluding rigidity and balance assessments) via web-based video conferencing. Intraclass coefficients (ICC) were calculated to determine the level of agreement between remote and in-person assessments. Participants also completed a survey on their interest in telemedicine. RESULTS: Thirteen individuals underwent baseline assessments, eleven (85%) participants completed at least one virtual visit, and 27 (82%) of 33 total virtual visits were completed. Remote motor scores demonstrated good reliability (ICC = 0.78; n = 11) compared to in-person motor scores. Test-retest reliability of motor scores conducted remotely was excellent (ICC = 0.90; n = 11). Participants expressed moderate future interest in using virtual visits to participate in research and to receive care. CONCLUSION: In this pilot study, virtual visits into the home were feasible and reliable for conducting motor assessments in HD. Larger scale studies need to confirm and generalize these findings to a broader population of participants.

Randomized controlled clinical trial of "virtual house calls" for Parkinson disease.

IMPORTANCE: The burden of neurological disorders is increasing, but access to care is limited. Providing specialty care to patients via telemedicine could help alleviate this growing problem. OBJECTIVE: To evaluate the feasibility, effectiveness, and economic benefits of using web-based videoconferencing (telemedicine) to provide specialty care to patients with Parkinson disease in their homes. DESIGN: A 7-month, 2-center, randomized controlled clinical trial. SETTING: Patients' homes and outpatient clinics at 2 academic medical centers. PARTICIPANTS: Twenty patients with Parkinson disease with Internet access at home. INTERVENTION: Care from a specialist delivered remotely at home or in person in the clinic. MAIN OUTCOME MEASURES: The primary outcome variable was feasibility, as measured by the percentage of telemedicine visits completed as scheduled. Secondary outcome measures included clinical benefit, as measured by the 39-item Parkinson Disease Questionnaire, and economic value, as measured by time and travel. RESULTS: Twenty participants enrolled in the study and were randomly assigned to telemedicine (n = 9) or in-person care (n = 11). Of the 27 scheduled telemedicine visits, 25 (93%) were completed, and of the 33 scheduled in-person visits, 30 (91%) were completed (P = .99). In this small study, the change in quality of life did not differ for those randomly assigned to telemedicine compared with those randomly assigned to in-person care (4.0-point improvement vs 6.4-point improvement; P = .61). Compared with in-person visits, each telemedicine visit saved participants, on average, 100 miles of travel and 3 hours of time. CONCLUSION AND RELEVANCE: Using web-based videoconferencing to provide specialty care at home is feasible, provides value to patients, and may offer similar clinical benefit to that of in-person care. Larger studies are needed to determine whether the clinical benefits are indeed comparable to those of in-person care and whether the results observed are generalizable. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01476306.