Brief Report: Combination of Osimertinib and Dacomitinib to Mitigate Primary and Acquired Resistance in EGFR-Mutant Lung Adenocarcinomas.

PURPOSE: Primary and acquired resistance to osimertinib remain significant challenges for patients with EGFR-mutant lung cancers. Acquired EGFR alterations such as EGFR T790M or C797S mediate resistance to EGFR tyrosine kinase inhibitors (TKI) and combination therapy with dual EGFR TKIs may prevent or reverse on-target resistance. PATIENTS AND METHODS: We conducted two prospective, phase I/II trials assessing combination osimertinib and dacomitinib to address on-target resistance in the primary and acquired resistance settings. In the initial therapy study, patients received dacomitinib and osimertinib in combination as initial therapy. In the acquired resistance trial, dacomitinib with or without osimertinib was administered to patients with EGFR-mutant lung cancers with disease progression on osimertinib alone and evidence of an acquired EGFR second-site mutation. RESULTS: Cutaneous toxicities occurred in 93% (any grade) of patients and diarrhea in 72% (any grade) with the combination. As initial therapy, the overall response to the combination was 73% [95% confidence interval (CI), 50%-88%]. No acquired secondary alterations in EGFR were observed in any patients at progression. In the acquired resistance setting, the overall response was 14% (95% CI, 1%-58%). CONCLUSIONS: We observed no acquired secondary EGFR alterations with dual inhibition of EGFR as up-front treatment, but this regimen was associated with greater toxicity. The combination was not effective in reversing acquired resistance after development of a second-site acquired EGFR alteration. Our study highlights the need to develop better strategies to address on-target resistance in patients with EGFR-mutant lung cancers.

Targeting NFE2L2/KEAP1 Mutations in Advanced NSCLC With the TORC1/2 Inhibitor TAK-228.

INTRODUCTION: Increased insight into the mutational landscape of squamous cell lung cancers (LUSCs) in the past decade has not translated into effective targeted therapies for patients with this disease. NRF2, encoded by NFE2L2, and its upstream regulator, KEAP1, control key aspects of redox balance and are frequently mutated in NSCLCs. METHODS: Here, we describe the specific potent activity of TAK-228, a TORC1/2 inhibitor, in NSCLC models harboring NRF2-activating alterations and results of a phase 2 clinical trial of TAK-228 in patients with advanced NSCLC harboring NRF2-activating alterations including three cohorts (NFE2L2-mutated LUSC, KEAP1-mutated LUSC, KRAS/NFE2L2- or KEAP1-mutated NSCLC). RESULTS: TAK-228 was most efficacious in a LUSC cohort with NFE2L2 alterations; the overall response rate was 25% and median progression-free survival was 8.9 months. Additional data suggest that concurrent inhibition of glutaminase with the glutaminase inhibitor CB-839 might overcome metabolic resistance to therapy in these patients. CONCLUSIONS: TAK-228 has single-agent activity in patients with NRF2-activated LUSC. This study reframes oncogenic alterations as biologically relevant based on their downstream effects on metabolism. This trial represents, to the best of our knowledge, the first successful attempt at metabolically targeting NSCLC and identifies a promising targeted therapy for patients with LUSC, who are bereft of genotype-directed therapies.

Phase I trial of the TNF-α inhibitor certolizumab plus chemotherapy in stage IV lung adenocarcinomas.

We previously identified a chemotherapy-induced paracrine inflammatory loop that paradoxically mitigates the anti-tumor effect of chemotherapy and triggers metastatic propagation in breast and lung cancer models. Therefore, we sought to further validate and translate these findings into patient care by coupling the anti-TNF-α drug certolizumab pegol with standard cisplatin doublet chemotherapy. Here we first validate the anti-metastatic effect of certolizumab in a liver-metastatic Lewis Lung Carcinoma model. We then evaluate the safety, efficacy, and pharmacodynamic effects of certolizumab with cisplatin and pemetrexed in an open label Phase 1 clinical trial (NCT02120807) of eighteen adult patients with stage IV lung adenocarcinomas. The primary outcome is maximum tolerated dose. Secondary outcomes are response rate and progression-free survival (PFS); pharmacodynamic changes in blood and tumor are evaluated as a correlative outcome. There were nine partial responses among 16 patients evaluable (56%, 95% CI 30 to 80%). The median duration of response was 9.0 months (range 5.9 to 42.6 months) and median PFS was 7.1 months (95% CI 6.3 to NR). The standard 400 mg dose of certolizumab, added to cisplatin and pemetrexed, is well-tolerated and, as a correlative endpoint, demonstrates potent pharmacodynamic inhibition of peripheral cytokines associated with the paracrine inflammatory loop.

Tepotinib: Management of Adverse Events in Patients With MET Exon 14 Skipping Non-Small Cell Lung Cancer.

BACKGROUND: Tepotinib, a highly selective, oral, once-daily MET inhibitor, has been approved for treatment of metastatic MET exon 14 skipping non-small cell lung cancer. OBJECTIVES: This article provides nurse-specific recommendations for identification and management of tepotinib adverse events (AEs). METHODS: Guidance on monitoring and proactive/reactive AE management was developed based on published literature and real-world nursing experience. Case studies of VISION trial participants were summarized to illustrate key principles. FINDINGS: Tepotinib AEs are generally mild to moderate and manageable, and can include peripheral edema, hypoalbuminemia, nausea, diarrhea, and creatinine increase. Alongside supportive care, tepotinib interruption and dose reduction is recommended for grade 3 AEs. For peripheral edema, proactive monitoring is crucial, and treatment interruption (including frequent, short treatment holidays) should be considered early. Nursing management of tepotinib AEs includes proactive monitoring, patient education, and interprofessional team coordination.

Phase 1 Clinical Trial of Trametinib and Ponatinib in Patients With NSCLC Harboring KRAS Mutations.

INTRODUCTION: Somatic KRAS mutations occur in 25% of patients with NSCLC. Treatment with MEK inhibitor monotherapy has not been successful in clinical trials to date. Compensatory activation of FGFR1 was identified as a mechanism of trametinib resistance in KRAS-mutant NSCLC, and combination therapy with trametinib and ponatinib was synergistic in in vitro and in vivo models. This study sought to evaluate this drug combination in patients with KRAS-mutant NSCLC. METHODS: A phase 1 dose escalation study of trametinib and ponatinib was conducted in patients with advanced NSCLC with KRAS mutations. A standard 3-plus-3 dose escalation was done. Patients were treated with the study therapy until intolerable toxicity or disease progression. RESULTS: A total of 12 patients with KRAS-mutant NSCLC were treated (seven at trametinib 2 mg and ponatinib 15 mg, five at trametinib 2 mg and ponatinib 30 mg). Common toxicities observed were rash, diarrhea, and fever. Serious adverse events potentially related to therapy were reported in five patients, including one death in the study and four cardiovascular events. Serious events were observed at both dose levels. Of note, 75% (9 of 12) were assessable for radiographic response and no confirmed partial responses were observed. The median time on study was 43 days. CONCLUSIONS: In this phase 1 study, in patients with KRAS-mutant advanced NSCLC, combined treatment with trametinib and ponatinib was associated with cardiovascular and bleeding toxicities. Exploring the combination of MEK and FGFR1 inhibition in future studies is potentially warranted but alternative agents should be considered to improve safety and tolerability.

Erlotinib and Trametinib in Patients With EGFR-Mutant Lung Adenocarcinoma and Acquired Resistance to a Prior Tyrosine Kinase Inhibitor.

Inhibition of the MEK/ERK pathway is critical for Bcl-2-like protein 11 (BIM)-mediated epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI)-induced apoptosis, and dysregulation of this pathway may be a mechanism of acquired resistance. Therefore, MEK inhibition with trametinib and an EGFR TKI may resensitize tumors with acquired resistance. Limited targeted therapies are available after progression on EGFR TKIs, and it is in this setting that we completed a phase I/II study of erlotinib and trametinib. METHODS: Patients with metastatic EGFR-mutant lung adenocarcinoma and acquired resistance to an EGFR TKI received combination erlotinib 75 mg and trametinib 1.5 mg daily until progression or unacceptable side effects. The primary objective was objective response rate determined using RECIST version 1.1. RESULTS: Twenty-three patients were accrued; patients had received a median of two lines of prior TKI therapy (61% prior osimertinib), and 48% had acquired EGFR T790M. We confirmed one partial response (1/23, 4%, 95% CI, 0 to 22). The median progression-free survival was 1.8 months, and the median overall survival was 21 months. Diarrhea (87%), acneiform rash (87%), and fatigue (52%) were the most common treatment-related adverse events. Two patients who had tumor shrinkage both harbored a BRAF fusion. CONCLUSION: Addition of trametinib to erlotinib in the acquired resistance setting in an unselected population is not efficacious. Future studies should focus on targeted therapies in molecularly selected populations. Acquired BRAF fusions in patients with EGFR-sensitizing mutations may be a molecular subset where EGFR and MEK combination therapy could be studied further.

Pilot Study of Dacomitinib for Patients With Metastatic EGFR-Mutant Lung Cancers With Disease Progression After Initial Treatment With Osimertinib.

Patients with EGFR-mutant lung cancer have no approved targeted therapies after disease progression on first-line osimertinib, a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI). Preclinical studies suggest that tumors with both EGFR-sensitizing alteration and acquired second-site EGFR resistance alterations after treatment with osimertinib retain sensitivity to second-generation EGFR TKIs. We hypothesized that dacomitinib, a pan-human epidermal growth factor receptor TKI, may be effective in this setting. METHODS: In this phase II study, patients who had progressed on first-line osimertinib were treated with dacomitinib 45 mg orally daily until disease progression or intolerability. The primary end point was objective response rate. RESULTS: We enrolled 12 patients. Two partial responses were documented (17% objective response rate; 95% CI, 5 to 45). The median progression-free survival was 1.8 months (95% CI, 1.6 to not reached). One patient with an original sensitizing EGFR G719A mutation and one patient without molecular testing available had partial responses, whereas 0 of the 3 patients with second-site acquired EGFR resistance mutations (two C797S and one G724S) met the response criteria. The patient with EGFR G719A has an ongoing response at 17 months, which exceeds prior time on osimertinib (11 months). CONCLUSION: In the first trial evaluating a second-generation EGFR TKI after first-line third-generation osimertinib, we found that dacomitinib after disease progression on osimertinib has limited benefit.

Effect of Osimertinib and Bevacizumab on Progression-Free Survival for Patients With Metastatic EGFR-Mutant Lung Cancers: A Phase 1/2 Single-Group Open-Label Trial.

Importance: The 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. Design, Setting, and Particiants: From August 15, 2016, to May 15, 2018, 49 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. Interventions: All patients received osimertinib, 80 mg daily, and bevacizumab, 15 mg/kg once every 3 weeks. Main Outcomes and Measures: The 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 Relevance: The 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. Trial Registration: ClinicalTrials.gov Identifier: NCT02803203.

A Phase II Trial of Albumin-Bound Paclitaxel and Gemcitabine in Patients with Newly Diagnosed Stage IV Squamous Cell Lung Cancers.

PURPOSE: Gemcitabine and albumin-bound paclitaxel (ABP) exhibit synergistic antitumor efficacy, with ABP serving to increase the intratumoral gemcitabine concentration. Both drugs are active in squamous cell lung cancers (SQCLC) and are conventional partners for carboplatin. We hypothesized that combining gemcitabine and ABP would enhance the antitumor activity in patients with advanced SQCLCs. PATIENTS AND METHODS: This was a Simon two-stage, open-label, single-arm, multicenter phase II study that enrolled patients between August 1, 2015 and June 1, 2018. We enrolled 37 patients with chemotherapy-naïve, PD-L1 low/unknown advanced stage IV SQCLC. Patients were administered weekly intravenous gemcitabine (1,000 mg/m2) plus ABP (100 mg/m2) in a 3-week on, 1-week off schedule during stage I and a 2-week on, 1-week off schedule in stage II. The primary endpoint was best objective response rate (ORR). Next-generation sequencing by MSK-IMPACT was used to calculate tumor mutation burden and genome doubling and assess somatic variants for correlations with efficacy. RESULTS: Thirty-two patients were evaluable for response assessment. The study satisfied its primary endpoint, with confirmed partial responses in 18 of 32 patients and a complete response in 1 patient [ORR 59%; 95% confidence interval (CI), 42%-74%]. Median progression-free survival (PFS), a secondary endpoint, was 7.5 (95% CI, 6.7-10.5) months. There were no unexpected toxicities. CONCLUSIONS: Gemcitabine plus ABP was a safe, tolerable, and effective first-line therapy for patients with chemotherapy-naïve SQCLCs, with an ORR and median PFS substantially higher than carboplatin doublet regimens and efficacy comparable with carboplatin plus taxane plus pembrolizumab.

Exceptional responders with invasive mucinous adenocarcinomas: a phase 2 trial of bortezomib in patients with KRAS G12D-mutant lung cancers.

KRAS G12D-mutant/p53-deficient non-small-cell lung cancer (NSCLC) models are dependent on the NF-κB pathway that can be down-regulated by the proteasome inhibitor bortezomib. Two exceptional responders were observed on prior clinical trials of bortezomib, both of whom had KRAS G12D-mutant NSCLC, prompting the initiation of this single-center phase 2 trial. Patients with advanced KRAS G12D-mutant NSCLC were eligible. Bortezomib was administered at 1.3 mg/m2 subcutaneously (days 1, 4, 8, 11; 21-d cycle) until progression or unacceptable toxicity. The primary objective was best objective response (RECIST v1.1). Sixteen patients with KRAS G12D-mutant lung adenocarcinomas were treated. Patients had a median pack year smoking history of 4 (range 0-45). A partial response (PR) was observed in one patient (-66% from baseline) and stable disease in five patients on the first stage of this study (overall response rate of 6%, 95% CI: 0.2-30.2), and further patients were not accrued. The median progression-free survival was 1 mo (95% CI: 1-6). The median overall survival was 13 mo (95% CI: 6-NA). The most common treatment-related adverse events were fatigue (38%) and diarrhea (26%). TP53 status did not predict response on exploratory testing. Of note, the patient with a PR had a unique subtype of lung adenocarcinoma-invasive mucinous adenocarcinomas (IMA)-and had rapid clinical improvement and substantial disease regression, which was also previously observed in two other patients with advanced KRAS G12D-mutant lung cancer with IMAs who received bortezomib on separate clinical trials. Exceptional responses to bortezomib can be achieved in KRAS G12D-mutant NSCLCs. KRAS G12D mutation alone, however, is not a robust predictor of response. Further evaluation should only be performed after further elucidation of other factors such as co-occurring alterations and histologic subtype such as IMA that may predict sensitivity to therapy.

A Phase II Trial of Sorafenib and Dacarbazine for Leiomyosarcoma, Synovial Sarcoma, and Malignant Peripheral Nerve Sheath Tumors.

BACKGROUND: Sorafenib and dacarbazine have low single-agent response rates in metastatic sarcomas. As angiogenesis inhibitors can enhance the efficacy of chemotherapy, we investigated the combination of sorafenib and dacarbazine in select sarcoma subtypes. MATERIALS AND METHODS: Patients with leiomyosarcoma (LMS), synovial sarcoma (SS), or malignant peripheral nerve sheath tumors (MPNST) with up to two previous lines of therapy and adequate hepatic, renal, and marrow function received 3-week cycles of sorafenib at 400 mg oral twice daily and dacarbazine 1,000 mg/m2 intravenously (later reduced to 850 mg/m2). Patients were evaluated for response every 6 weeks. The primary objective was to determine the disease control rate (DCR) of sorafenib plus dacarbazine in the selected sarcoma subtypes. RESULTS: The study included 37 patients (19 female); median age was 55 years (range 26-87); and histologies included LMS (22), SS (11), and MPNST (4). The DCR was 46% (17/37). Median progression-free survival was 13.4 weeks. The RECIST response rate was 14% (5/37). The Choi response rate was 51% (19/37). Median overall survival was 13.2 months. Of the first 25 patients, 15 (60%) required dacarbazine dose reductions for hematologic toxicity, with one episode of grade 5 neutropenic fever. After reducing the starting dose of dacarbazine to 850 mg/m2, only 3 of the final 12 (25%) patients required dose reduction. CONCLUSION: This phase II study met its primary endpoint with an 18-week DCR of 46%. The clinical activity of dacarbazine plus sorafenib in patients with these diagnoses is modest. IMPLICATIONS FOR PRACTICE: Metastatic soft tissue sarcomas are a heterogeneous group of relatively rare malignancies. Most patients are treated with cytotoxic chemotherapy or targeted therapy in the form of tyrosine kinase inhibitors. Response rates are relatively low, and there is a need for better therapies. This clinical trial demonstrates that combining a cytotoxic therapy (dacarbazine) with an antiangiogenic small molecule (sorafenib) is feasible and associated with favorable disease-control rates; however, it also increases the potential for significant toxicity.

Twice weekly pulse and daily continuous-dose erlotinib as initial treatment for patients with epidermal growth factor receptor-mutant lung cancers and brain metastases.

BACKGROUND: In a phase 1 study of pulse/continuous-dose erlotinib, no patient had disease progression in the central nervous system (CNS). This expansion cohort of the phase 1 study tested the same regimen in a cohort of individuals with epidermal growth factor receptor (EGFR)-mutant lung cancers with untreated brain metastases. METHODS: Patients had not received EGFR tyrosine kinase inhibitors or radiation for brain metastases. All received 1200 mg of erlotinib on days 1 and 2 and 50 mg on days 3 to 7 weekly. The primary endpoints were the overall and CNS response rates (according to version 1.1 of the Response Evaluation Criteria in Solid Tumors). RESULTS: Between May 2015 and August 2016, 19 patients were enrolled. Forty-two percent of the patients had target brain lesions, and the median size of the target brain lesions was 13 mm. Overall, 14 patients (74%; 95% confidence interval [CI], 51%-89%) had partial responses. The response rate in brain metastases was 75%. The overall median progression-free survival was 10 months (95% CI, 7 months to not reached). Only 3 patients (16%) had CNS progression. To date, 4 patients required CNS radiation at some time during their course. The adverse events (any grade) seen in 10% or more of the patients were rash, diarrhea, nausea, an increase in alanine aminotransferase, and fatigue. CONCLUSIONS: Pulse/continuous-dose erlotinib produced a 74% overall response rate and a 75% response rate in brain metastases in patients with EGFR-mutant lung cancers and untreated brain metastases. CNS control persisted even after progression elsewhere. Although this regimen did not improve progression-free survival or delay the emergence of EGFR T790M, it prevented progression in the brain and could be useful in situations in which CNS control is critical. Cancer 2018;124:105-9. © 2017 American Cancer Society.

Prognostic impact of TTF-1 expression in patients with stage IV lung adenocarcinomas.

OBJECTIVES: Thyroid transcription factor 1 (TTF-1) is routinely tested in the diagnostic evaluation of suspected lung cancers, is commonly expressed by lung adenocarcinomas, and may modulate lung cancer biology. We examined the role of TTF-1 as a predictive and prognostic marker in patients with advanced lung adenocarcinomas. MATERIALS AND METHODS: We analyzed clinical, pathologic, and molecular features, treatments received, and overall survival obtained from the medical records of 479 consecutive patients at a single site with stage IV lung adenocarcinomas and evaluable TTF-1 expression. TTF-1 expression was determined by immunohistochemistry using antibody 8G7G3/1. RESULTS AND CONCLUSION: TTF-1 expression was evaluable in 479 (75%) of all patients reviewed, and was positive in 383 (80%, 95% CI 76-83%). Clinicopathologic features were similar between TTF-1 positive and TTF-1 negative tumors, except EGFR mutations were more common in TTF-1 positive cases (24% vs 6%, p<0.001). In univariate analysis, overall survival was significantly longer in patients with TTF-1 positive versus TTF-1 negative tumors (18 months vs 9 months, p<0.0001). In multivariate analysis, TTF-1 positivity remained associated with better overall survival (HR=0.38, p<0.0001), exceeding the prognostic impact of Karnofsky performance status >/=80% (HR 0.62, p=0.0003) and receipt of first-line combination chemotherapy or targeted therapy (HR relative to first-line single agent chemotherapy 0.59, p=0.05 and 0.51, p=0.05 respectively). Both patients with TTF-1 positive and TTF-1 negative cancers had longer durations of initial therapy when treated with pemetrexed-based chemotherapy. In patients with advanced lung adenocarcinomas, TTF-1 expression is associated with better survival but is not predictive of distinct benefit from pemetrexed-based chemotherapy.

Consumptive coagulopathy in angiosarcoma: a recurrent phenomenon?

Objectives. To report the prevalence of consumptive coagulopathy in angiosarcoma patients seen at a single center. Methods. We retrospectively reviewed case records of 42 patients diagnosed with angiosarcoma at Mount Sinai Hospital between 2000 and 2013. Results. Seven patients (17%) met clinical criteria for disseminated intravascular coagulation (DIC) in absence of concomitant clinical states known to cause coagulopathy or myelosuppression. In all patients who received systemic antineoplastic therapy with resultant disease response or stability, DIC resolved in tandem with clinical improvement. DIC recurred at time of disease progression in all cases. Two patients had bulky disease, defined as diameter of largest single or contiguous tumor mass measuring 5 cm or more. All patients demonstrated an aggressive clinical course with short duration of disease control and demise within 1 year. In contrast, evaluation over the same period of 17 epithelioid hemangioendothelioma patients serving as a clinical control group revealed no evidence of DIC. Conclusion. Angiosarcomas can be associated with a consumptive coagulopathy arising in tandem with disease activity. Vigilance for this complication will be needed in the course of often aggressive multimodality therapy. The potential utility of coagulopathy as a prognostic biomarker will need to be explored in future studies.

Malignant peripheral nerve sheath tumors.

Malignant peripheral nerve sheath tumors (MPNST) are uncommon, biologically aggressive soft tissue sarcomas of neural origin that pose tremendous challenges to effective therapy. In 50% of cases, they occur in the context of neurofibromatosis type I, characterized by loss of function mutations to the tumor suppressor neurofibromin; the remainder arise sporadically or following radiation therapy. Prognosis is generally poor, with high rates of relapse following multimodality therapy in early disease, low response rates to cytotoxic chemotherapy in advanced disease, and propensity for rapid disease progression and high mortality. The last few years have seen an explosion in data surrounding the potential molecular drivers and targets for therapy above and beyond neurofibromin loss. These data span multiple nodes at various levels of cellular control, including major signal transduction pathways, angiogenesis, apoptosis, mitosis, and epigenetics. These include classical cancer-driving genetic aberrations such as TP53 and phosphatase and tensin homolog (PTEN) loss of function, and upregulation of mitogen-activated protein kinase (MAPK) and (mechanistic) target of rapamycin (TOR) pathways, as well as less ubiquitous molecular abnormalities involving inhibitors of apoptosis proteins, aurora kinases, and the Wingless/int (Wnt) signaling pathway. We review the current understanding of MPNST biology, current best practices of management, and recent research developments in this disease, with a view to informing future advancements in patient care.

Activity of Sorafenib against desmoid tumor/deep fibromatosis.

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 Institutional Review Board (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. RESULTS: Sorafenib was the 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 shown evidence of progressive disease by imaging, whereas 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 response evaluation criteria in solid tumors (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. DISCUSSION: 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.

Clinical outcomes of systemic therapy for patients with deep fibromatosis (desmoid tumor).

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.