Learning Objectives Explain the characteristics and treatment of malignant peripheral nerve sheath tumors, both in relation to neurofibromatosis type I and otherwise. Cite the unique challenges in optimal management of malignant peripheral nerve sheath tumors. Appraise the large amount of new data surrounding the potential molecular drivers, possible targets for therapy in this disease.

Background Desmoid tumors (deep fibromatoses) are clonal connective tissue malignancies that do not metastasize, but have a significant risk of local recurrence, and are associated with morbidity and occasionally mortality. Responses of desmoid patients to sorafenib on an expanded access program led us to review our experience. Methods After IRB approval, we reviewed data for 26 patients with desmoid tumors treated with sorafenib. Sorafenib was administered at 400 mg oral daily and adjusted for toxicity. Findings Sorafenib was first line therapy in 11/26 patients and the remaining 15/26 had received a median of 2 prior lines of therapy. Twenty-three of 26 patients had demonstrated evidence of progressive disease by imaging, while 3 patients had achieved maximum benefit or toxicity with chemotherapy. Sixteen of 22 (~70%) patients reported significant improvement of symptoms. At a median of 6 months (2–29) of treatment, the best RECIST 1.1 response included 6/24 (25%) patients with partial response (PR), 17/24 (70%) with stable disease and 1 with progression and death. Twelve of 13 (92%) patients evaluated by MRI had >30% decrease in T2 signal intensity, an indirect metric for increased fibrosis and loss of cellularity. Eighty percent of patients with radiological benefit had extra-abdominal desmoids. Interpretation Sorafenib is active against desmoid tumors. A prospective, randomized clinical trial of sorafenib against other active agents is warranted. Loss of MRI T2 signal may be a useful surrogate for defining responses, but requires validation by examination of tumor pathology.

BACKGROUND: In the current study, the authors examined the outcomes of patients with desmoid tumors who received systemic therapy at a single institution to provide a basis for the examination of newer agents. METHODS: Records of patients with desmoid tumors who were treated with chemotherapy at the study institution were reviewed. The activity of nonsteroidal anti-inflammatory drugs was not addressed. Patients without measurable disease and those receiving therapy could not be documented, and those receiving prophylactic therapy were excluded. RESULTS: A total of 68 patients received 157 lines of therapy. At the time of last follow-up, 9 patients had died, 7 of progressive disease. The cohort was 62% female, with a median age of 32.5 years. Approximately 32% of the patients had Gardner syndrome. The median follow-up was 63 months, and patients received a median of 2 lines of therapy. An intra-abdominal primary tumor location was the most common (44%). The greatest Response Evaluation Criteria in Solid Tumors (RECIST) response rate was observed with anthracyclines and hormonal therapy and the lowest response was noted with single-agent dacarbazine/temozolomide or tyrosine kinase inhibitors, principally imatinib. On multivariate analysis, macroscopic nodular morphology and the presence of Gardner syndrome were the only tumor factors found to be associated with a greater time to disease progression. CONCLUSIONS: Compared with other agents, antiestrogens and anthracycline-containing regimens appear to be associated with a higher radiological response rate against desmoid tumors. Systemic therapy can be successful in patients with desmoid tumors, and is a viable option in lieu of morbid or disabling surgery. Cancer 2010;116:2258-65.

IMPORTANCEThe combination of erlotinib and bevacizumab as initial treatment of epidermal growth factor receptor (EGFR [OMIM 131550])-mutant lung cancers improves progression-free survival (PFS) compared with erlotinib alone. Because osimertinib prolongs PFS compared with erlotinib, this trial was designed to study the combination of osimertinib and bevacizumab as first-line treatment.OBJECTIVES To determine the safety and tolerability of osimertinib and bevacizumab combination treatment and assess the 12-month PFS of the combination in patients with metastatic EGFR-mutant lung cancers. From August 15, 2016, to May 15, 2018 patients with metastatic EGFR-mutant lung cancers were enrolled in this interventional clinical trial, conducted at a single academic cancer center. In the phase 1 portion of the study, a standard 3 + 3 dose de-escalation design was used to determine the maximum tolerated dose of osimertinib and bevacizumab. In the phase 2 portion of the study, patients were treated at the maximum tolerated dose defined in the phase 1 portion. Statistical analysis was performed from August 1 to October 1, 2019. DESIGN, SETTING, AND PARTICIANTSINTERVENTIONS All patients received osimertinib, 80 mg daily, and bevacizumab, 15 mg/kg once every 3 weeks. MAIN OUTCOMES AND MEASURESThe primary objective of the phase 2 portion of the study was to determine the number of patients receiving the combination of osimertinib and bevacizumab who were progression free at 12 months. Secondary end points included overall response rate, median PFS, overall survival, and definition of the toxic effects of the combination treatment. RESULTS Among the 49 patients in the study (34 women; median age, 60 years [range, 36-83 years]), PFS at 12 months was 76% (95% CI, 65%-90%). The overall response rate was 80% (95% CI, 67%-91%), and median PFS was 19 months (95% CI, 15-24 months). Of the 6 patients with measurable central nervous system disease, all had a partial or complete central nervous system response. Persistent detection of EGFR-mutant circulating tumor (ct)DNA at 6 weeks was associated with shorter median PFS (clearance at 6 weeks, 16.2 months [95% CI, 13 months to not reached]; and no clearance at 6 weeks, 9.8 months [95% CI, 4 months to not reached]; P = .04) and median overall survival (clearance at 6 weeks, not reached; and no clearance at 6 weeks, 10.1 months [95% CI, 6 months to not reached]; P = .002). Identified mechanisms of resistance included squamous cell transformation (n = 2) pleomorphic transformation (n = 1), and acquired EGFR L718Q (n = 1) and C797S (n = 1) mutations. CONCLUSIONS AND RELEVANCEThe combination of osimertinib and bevacizumab met the study's prespecified effectiveness end point. Persistent EGFR-mutant circulating tumor DNA at 6 weeks was associated with early progression and shorter survival. A randomized phase 3 study comparing osimertinib and bevacizumab with osimertinib alone is planned.