Hyperfibrinolysis during the treatment of rhabdomyosarcoma.

Background: Coagulopathies are frequently observed in alveolar rhabdomyosarcoma (ARMS), with disseminated intravascular coagulation (DIC) being the most common presentation. However, hyperfibrinolysis represents a distinct but often overlapping and potentially life-threatening subset of coagulation disorders that requires specific diagnostic and management approaches. Key Clinical Question: How can clinicians identify hyperfibrinolysis and what are the implications for management? Clinical Approach: This case report describes a 25-year-old man with metastatic ARMS arising from the prostate who developed persistent gross hematuria one week after initiating chemotherapy. A comprehensive coagulation workup was performed, including assessment of platelet count, prothrombin time, activated partial thromboplastin time, fibrinogen, D-dimer, and fibrin degradation products. Management included repletion of fibrinogen and the use of anti-fibrinolytic agents. Conclusion: Recognizing hyperfibrinolysis in ARMS patients is crucial for appropriate management. Clinicians should maintain a high index of suspicion for hyperfibrinolysis in ARMS patients presenting with severe coagulation abnormalities, particularly those with prostatic involvement or undergoing chemotherapy. In cases of primary hyperfibrinolysis, antifibrinolytic agents may be considered, whereas they are generally contraindicated in DIC.

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.

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.

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.

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.

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.