Dataset for reporting of gastrointestinal stromal tumours: recommendations from the International Collaboration on Cancer Reporting (ICCR).

Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal tumours of the gastrointestinal tract and are among the most frequent sarcomas. Accurate diagnosis, classification, and reporting are critical for prognostication and patient management, including selection of appropriate targeted therapy. Here we report on international consensus-based datasets for the pathology reporting of biopsy and resection specimens of GIST. The datasets were produced under the auspices of the International Collaboration on Cancer Reporting (ICCR), a global alliance of major international pathology and cancer organizations. An international expert panel consisting of pathologists, a surgical oncologist, and a medical oncologist produced a set of core and noncore data items for biopsy and resection specimens based on a critical review and discussion of current evidence. All professionals involved were subspecialized soft tissue tumour experts and affiliated with tertiary referral centres. Commentary was provided for each data item to explain its clinical relevance and the rationale for selection as a core or noncore element. Following international public consultation, the datasets, which include synoptic reporting guides, were finalized and ratified, and published on the ICCR website. These first international datasets for GIST are intended to promote high-quality, standardised pathology reporting. Their widespread adoption will improve consistency of reporting, facilitate multidisciplinary communication, and enhance comparability of data, all of which will ultimately help to improve the management of patients with GIST. All the ICCR datasets, including these on GIST, are freely available worldwide on the ICCR website (www.iccr-cancer.org/datasets).

Adolescent and Young Adult (AYA) Oncology, Version 2.2024, NCCN Clinical Practice Guidelines in Oncology.

This selection from the NCCN Guidelines for Adolescent and Young Adult (AYA) Oncology focuses on considerations for the comprehensive care of AYA patients with cancer. Compared with older adults with cancer, AYA patients have unique needs regarding treatment, fertility counseling, psychosocial and behavioral issues, and supportive care services. The complete version of the NCCN Guidelines for Adolescent and Young Adult (AYA) Oncology addresses additional aspects of caring for AYA patients, including risk factors, screening, diagnosis, and survivorship.

OER-073: A multicenter phase 2 study evaluating the role of pazopanib in angiosarcoma.

BACKGROUND: Angiosarcomas are rare mesenchymal sarcomas that can present as primary cutaneous or noncutaneous disease. They express a variety of vascular endothelial growth factor receptors. The authors hypothesized that the treatment of angiosarcoma with pazopanib, a multikinase inhibitor with activity against vascular endothelial growth factor receptors, would result in disease response and prolonged disease stabilization. METHODS: This was an open-label, phase 2 trial of pazopanib in patients who had incurable angiosarcoma. The co-primary end points were response according to the Response Evaluation Criteria in Solid Tumors and progression-free survival (PFS) at 3 months. The starting dose of pazopanib was 800 mg daily. RESULTS: Twenty-nine patients were accrued between 2011 and 2018, and 22 patients were evaluable for response. Toxicities were similar to those identified in prior reports. There was one partial response (3%), and the clinical benefit rate (including complete responses, partial responses, and stable disease) was 48%, which was observed more frequently in patients who had cutaneous disease. The median PFS was 14.4 weeks, and the 3-month PFS rate determined by Kaplan-Meier estimate was 54.6% (95% CI, 36.0%-82.9%), meeting the primary study objective. The Kaplan-Meier overall survival estimate was 16.1 months. CONCLUSIONS: Pazopanib therapy in patients who had incurable angiosarcoma was associated with meaningful disease control, especially in those who had cutaneous disease with limited objective responses. LAY SUMMARY: Angiosarcoma is a rare cancer that can be found on the skin or in internal organs. This study tested pazopanib, an oral targeted medication, to determine its benefit in patients with angiosarcoma who could not undergo the removal of their tumors by surgery. Pazopanib treatment was safe, and no new side effects were reported. The study showed that pazopanib controlled tumor growth in one half of patients at 3 months and was more common in angiosarcomas of the skin; it led to tumor shrinkage in a minority of patients (1 of 29).

National Trends in Treatment for Retroperitoneal Soft Tissue Sarcoma: A Modern Appraisal of Variability in Therapeutic Strategies.

BACKGROUND: Little level 1 evidence exists to guide multimodality treatment in retroperitoneal soft tissue sarcoma (RPS), which may lead to significant variation in therapeutic approaches. This analysis aimed to describe national RPS treatment trends and explore potential variability among low-/high-volume hospitals (LVH/HVHs). PATIENTS AND METHODS: In total, 5992 patients who underwent resection for primary RPS were retrospectively identified in the National Cancer Database (2004-2017). Time trend analyses examined rates of multivisceral resection (MVR), radiation, and chemotherapy use. LVHs were defined as those carrying out fewer than ten resections per year (N = 5433), whereas HVHs were defined as those carrying out ten or more (N = 559). Descriptive statistics and logistic regression models compared trends between groups. RESULTS: MVR was more frequent at HVHs (63.7% versus 43.5%, p < 0.001). Use of radiation varied widely by hospital volume. HVHs more frequently employed preoperative radiation as compared with LVHs (14.7% versus 8.1%, p < 0.001). Throughout the study period, LVHs increased utilization of preoperative radiation (2.6% to 12.0%, p < 0.001) whereas rates at HVHs remained stable. Overall, LVHs utilized postoperative radiation significantly more frequently as compared with HVHs (14.7% versus 2.7%, respectively, p < 0.001). Postoperative radiation at LVHs remained stable until 2013 and sharply declined thereafter (16.7% to 6.9%, p < 0.001). Rates of postoperative radiation use at HVHs remained lower than those at LVHs at all time points. CONCLUSIONS: Strategies for resection and radiation use at LVHs have trended towards those of HVHs. Current national implementation of preoperative radiation, MVR, and chemotherapy remains heterogeneous. These findings inform future trial design and support standardization of care.

Patient-reported outcomes in individuals with advanced gastrointestinal stromal tumor treated with ripretinib in the fourth-line setting: analysis from the phase 3 INVICTUS trial.

BACKGROUND: Ripretinib is a novel switch-control kinase inhibitor that inhibits KIT and PDGFRA signaling. In the INVICTUS phase 3 trial, ripretinib increased median progression-free survival and prolonged overall survival vs. placebo in ≥ fourth-line advanced GIST. Here, we report prespecified analysis of quality of life (QoL) as assessed by patient-reported outcome (PRO) measures and an exploratory analysis evaluating the impact of alopecia on QoL. METHODS: In the INVICTUS trial (NCT03353753), QoL was assessed using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30; physical function, role function, overall health, and overall QoL) and the EuroQoL 5-Dimension 5-Level (EQ-5D-5 L; visual analogue scale). Analysis of covariance (ANCOVA) models compared changes in scores from baseline to treatment cycle 2, day 1 within and between ripretinib and placebo. Within the ripretinib arm, repeated measures models assessed the impact of alopecia on QoL. RESULTS: Patients receiving ripretinib maintained QoL (as assessed by the EORTC QLQ-C30 and EQ-5D-5 L PRO measures) from baseline to cycle 2, day 1 whereas QoL declined with placebo, resulting in clinically significant differences between treatments (nominal P < 0.01). The most common treatment-emergent adverse event with ripretinib was alopecia; however, QoL was similarly maintained out to treatment cycle 10, day 1 in patients receiving ripretinib who developed alopecia and those who did not. CONCLUSION: PRO assessments in the INVICTUS trial suggest that patients on ripretinib maintain their QoL out to C2D1, unlike patients receiving placebo. Longitudinal QoL was maintained for patients receiving ripretinib out to cycle 10, day 1 (approximately 8 months; past the point of median progression-free survival with ripretinib [6.3 months]), even if the patients developed alopecia. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03353753 ; first posted: November 27, 2017.

NCCN Guidelines® Insights: Gastrointestinal Stromal Tumors, Version 2.2022.

Gastrointestinal stromal tumors (GIST) are the most common type of soft tissue sarcoma that occur throughout the gastrointestinal tract. Most of these tumors are caused by oncogenic activating mutations in the KIT or PDGFRA genes. The NCCN Guidelines for GIST provide recommendations for the diagnosis, evaluation, treatment, and follow-up of patients with these tumors. These NCCN Guidelines Insights summarize the panel discussion behind recent important updates to the guidelines, including revised systemic therapy options for unresectable, progressive, or metastatic GIST based on mutational status, and updated recommendations for the management of GIST that develop resistance to specific tyrosine kinase inhibitors.

Soft Tissue Sarcoma, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology.

Soft tissue sarcomas (STS) are rare malignancies of mesenchymal cell origin that display a heterogenous mix of clinical and pathologic characteristics. STS can develop from fat, muscle, nerves, blood vessels, and other connective tissues. The evaluation and treatment of patients with STS requires a multidisciplinary team with demonstrated expertise in the management of these tumors. The complete NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Soft Tissue Sarcoma provide recommendations for the diagnosis, evaluation, and treatment of extremity/superficial trunk/head and neck STS, as well as retroperitoneal/intra-abdominal STS, desmoid tumors, and rhabdomyosarcoma. This portion of the NCCN Guidelines discusses general principles for the diagnosis and treatment of retroperitoneal/intra-abdominal STS, outlines treatment recommendations, and reviews the evidence to support the guidelines recommendations.

Gastrointestinal Stromal Tumors: What Is the Best Sequence of TKIs?

OPINION STATEMENT: In our practice, we evaluate the mutation status of advanced unresectable disease to guide decisions on use of tyrosine kinase inhibitor (TKI) therapy. This review focuses on management of GIST with KIT and PDGFRA mutations. Imatinib is first-line treatment for unresectable gastrointestinal stromal tumors (GISTs) unless they harbor a PDGFRA D842V mutation; it is recommended to escalate imatinib to twice daily dosing for KIT exon 9 mutant tumors. When patients progress on first-line treatment, treatment is changed to sunitinib followed by regorafenib; while the spectrum of activity against resistance mutations varies with these agents, routine biopsies provide data on one area of disease and ctDNA has not been validated prospectively. For those with a PDGFRA D842V mutation, avapritinib is the first TKI to lead to tumor response and disease control. Ripretinib is approved in the 4th line setting, with limited data on its benefit for PDGFRA D842V GIST. Avapritinib can be considered for treatment beyond ripretinib for KIT mutant disease. The efficacy of other TKIs tested in GIST is reviewed. Ongoing therapy provides palliative benefit and should be continued given rapid decline observed off of treatment.

SMARCA2-NR4A3 is a novel fusion gene of extraskeletal myxoid chondrosarcoma identified by RNA next-generation sequencing.

Extraskeletal myxoid chondrosarcoma (EMC) is a rare sarcoma of uncertain differentiation, characterized by recurrent chromosomal translocation involving NR4A3 (9q22.33) in more than 90% of cases. Five fusion partners for NR4A3 have been described including: EWSR1 (22q12.2), TAF15 (17q12), FUS (16p11.2), TCF12 (15q21), and TFG (3q12.2). This report describes a patient with an EMC at the dorsum of the right foot. The tumor showed a cord-like and reticular pattern in a background of myxoid matrix. The tumor cells demonstrated an epithelioid morphology with prominent nucleoli. The tumor cells were positive for synaptophysin, GFAP, with focal positivity for CD117, S100, Cam5.2, and NSE, and negative for AE1/3, desmin, and SMA. An RNA next-generation sequencing test showed a SMARCA2-NR4A3 gene fusion which has not been previously reported. The exon 3 of SMARCA2 was fused to exon 3 of NR4A3. This fusion was confirmed by NR4A3 break-apart FISH, although both SMARCA2 (9p24.3) and NR4A3 (9q22.33) are located on chromosome 9. The tumor cells showed retained expression of INI1 and SMARCA2 by immunohistochemistry.

Defining the role of neoadjuvant systemic therapy in high-risk retroperitoneal sarcoma: A multi-institutional study from the Transatlantic Australasian Retroperitoneal Sarcoma Working Group.

BACKGROUND: In patients with retroperitoneal sarcoma (RPS), the incidence of recurrence after surgery remains high. Novel treatment approaches are needed. This retrospective study evaluated patients with primary, high-risk RPS who received neoadjuvant systemic therapy followed by surgery to 1) determine the frequency and potential predictors of radiologic tumor responses and 2) assess clinical outcomes. METHODS: Clinicopathologic data were collected for eligible patients treated at 13 sarcoma referral centers from 2008 to 2018. Univariable and multivariable logistic models were performed to assess the association between clinical predictors and response. Overall survival (OS) and crude cumulative incidences of local recurrence and distant metastasis were compared. RESULTS: Data on 158 patients were analyzed. A median of 3 cycles of neoadjuvant systemic therapy (interquartile range, 2-4 cycles) were given. The regimens were mostly anthracycline based; however, there was significant heterogeneity. No patients demonstrated a complete response, 37 (23%) demonstrated a partial response (PR), 88 (56%) demonstrated stable disease, and 33 (21%) demonstrated progressive disease (PD) according to the Response Evaluation Criteria in Solid Tumors, version 1.1. Only a higher number of cycles given was positively associated with PR (P = .005). All patients underwent complete resection, regardless of the tumor response. Overall, patients whose tumors demonstrated PD before surgery showed markedly worse OS (P = .005). An indication of a better clinical outcome was seen in specific regimens given for grade 3 dedifferentiated liposarcoma and leiomyosarcoma. CONCLUSIONS: In patients with high-risk RPS, the response to neoadjuvant systemic therapy is fair overall. Disease progression on therapy may be used to predict survival after surgery. Subtype-specific regimens should be further validated.

Avapritinib in Patients With Advanced Gastrointestinal Stromal Tumors Following at Least Three Prior Lines of Therapy.

BACKGROUND: Most gastrointestinal stromal tumors (GIST) driven by KIT or platelet-derived growth factor receptor A (PDGFRA) mutations develop resistance to available tyrosine kinase inhibitor (TKI) treatments. NAVIGATOR is a two-part, single-arm, dose escalation and expansion study designed to evaluate safety and antineoplastic activity of avapritinib, a selective, potent inhibitor of KIT and PDGFRA, in patients with unresectable or metastatic GIST. MATERIALS AND METHODS: Eligible patients were 18 years or older with histologically or cytologically confirmed unresectable GIST and Eastern Cooperative Oncology Group performance status ≤2 and initiated avapritinib at 300 mg or 400 mg once daily. Primary endpoints were safety in patients who initiated avapritinib at 300 mg or 400 mg once daily and overall response rate (ORR) in patients in the safety population with three or more previous lines of TKI therapy. RESULTS: As of November 16, 2018, in the safety population (n = 204), the most common adverse events (AEs) were nausea (131 [64%]), fatigue (113 [55%]), anemia (102 [50%]), cognitive effects (84 [41%]), and periorbital edema (83 [41%]); 17 (8%) patients discontinued due to treatment-related AEs, most frequently confusion, encephalopathy, and fatigue. ORR in response-evaluable patients with GIST harboring KIT or non-D842V PDGFRA mutations and with at least three prior therapies (n = 103) was 17% (95% confidence interval [CI], 10-25). Median duration of response was 10.2 months (95% CI, 7.2-10.2), and median progression-free survival was 3.7 months (95% CI, 2.8-4.6). CONCLUSION: Avapritinib has manageable toxicity with meaningful clinical activity as fourth-line or later treatment in some patients with GIST with KIT or PDGFRA mutations. IMPLICATIONS FOR PRACTICE: In the NAVIGATOR trial, avapritinib, an inhibitor of KIT and platelet-derived growth factor receptor A tyrosine kinases, provided durable responses in a proportion of patients with advanced gastrointestinal stromal tumors (GIST) who had received three or more prior therapies. Avapritinib had a tolerable safety profile, with cognitive adverse events manageable with dose interruptions and modification in most cases. These findings indicate that avapritinib can elicit durable treatment responses in some patients with heavily pretreated GIST, for whom limited treatment options exist.

Clinical Benefit of Ripretinib Dose Escalation After Disease Progression in Advanced Gastrointestinal Stromal Tumor: An Analysis of the INVICTUS Study.

BACKGROUND: Ripretinib 150 mg once daily (QD) is indicated for advanced gastrointestinal stromal tumors (GISTs) as at least fourth-line therapy. In INVICTUS, ripretinib intrapatient dose escalation (IPDE) to 150 mg b.i.d. was allowed after progressive disease (PD) on 150 mg QD by blinded independent central review using modified RECIST 1.1. We report the efficacy and safety of ripretinib IPDE to 150 mg b.i.d. after PD among patients randomized to ripretinib 150 mg QD in the INVICTUS study. MATERIALS AND METHODS: Tumor imaging was performed every 28-day cycle for the first four cycles in the ripretinib 150 mg QD period and then every other cycle, including the 150 mg b.i.d. PERIOD: Among the ripretinib IPDE patients, progression-free survival (PFS)1 was the time from randomization until PD; PFS2 was the time from the first dose of ripretinib 150 mg b.i.d. to PD or death. RESULTS: Among 43 ripretinib IPDE patients, median PFS1 was 4.6 months (95% confidence interval [CI], 2.7-6.4) and median PFS2 was 3.7 months (95% CI, 3.1-5.3). Median overall survival was 18.4 months (95% CI, 14.5-not estimable). Ripretinib 150 mg b.i.d. (median duration of treatment 3.7 months) was well tolerated with new or worsening grade 3-4 treatment-emergent adverse events (TEAEs) of anemia in six (14%) and abdominal pain in three (7%) patients. Ripretinib 150 mg b.i.d. was discontinued because of TEAEs in seven (16%) patients. CONCLUSION: Ripretinib 150 mg b.i.d. after PD on 150 mg QD may provide additional clinically meaningful benefit with an acceptable safety profile in patients with at least fourth-line GISTs. IMPLICATIONS FOR PRACTICE: Of the 85 patients with advanced gastrointestinal stromal tumor having received at least three prior anticancer therapies randomized to ripretinib 150 mg once daily (QD) in the phase III INVICTUS study, 43 underwent ripretinib intrapatient dose escalation (IPDE) to 150 mg b.i.d. after progressive disease (PD). Median progression-free survival was 4.6 months before and 3.7 months after ripretinib IPDE. The safety profile of ripretinib 150 mg b.i.d. was acceptable. These findings indicate ripretinib IPDE to 150 mg b.i.d. may provide additional clinical benefit in patients with PD on ripretinib 150 mg QD, for whom limited treatment options exist.

Clinical efficacy comparison of avapritinib with other tyrosine kinase inhibitors in gastrointestinal stromal tumors with PDGFRA D842V mutation: a retrospective analysis of clinical trial and real-world data.

BACKGROUND: Avapritinib, a potent inhibitor of KIT and platelet-derived growth factor receptor A (PDGFRA) tyrosine kinases, has demonstrated unprecedented clinical activity in PDGFRA D842V-mutant gastrointestinal stromal tumors (GIST). METHODS: This retrospective analysis compared efficacy of avapritinib in patients enrolled in the NAVIGATOR phase 1 trial (NCT02508532) with the efficacy of other tyrosine kinase inhibitors (TKIs) in patients with unresectable/metastatic PDGFRA D842V-mutant GIST enrolled in a retrospective natural history study (Study 1002). The primary endpoint was overall survival (OS) from the start of reference treatment (avapritinib for NAVIGATOR patients or first-line TKI for treatment of unresectable/metastatic GIST for Study 1002 patients); the secondary endpoint was progression-free survival (PFS). Adjusted Kaplan-Meier survival curves were compared by Cox regression. RESULTS: Fifty-six (NAVIGATOR) and 19 (Study 1002) patients with PDGFRA D842V-mutant GIST were evaluated; of the 56 patients from NAVIGATOR, a subgroup of patients treated with either 300 mg (recommended phase 2 dose) or 400 mg (maximum tolerated dose) avapritinib starting dose (n = 38) were analyzed separately. Patient characteristics were adjusted for imbalances by propensity score between the study groups. Inverse probability of treatment weighting-adjusted Kaplan-Meier analysis of OS showed median OS was not reached for NAVIGATOR patients treated with any of the avapritinib doses tested and was 12.6 months for Study 1002 patients; OS rate at 6/48 months was 100%/63% in NAVIGATOR and 56%/17% in Study 1002 (P = 0.0001). In the 300/400 mg subgroup, adjusted OS rates at 6/36 months were 100%/73 and 68%/20% in Study 1002 (P = 0.0016). Adjusted median PFS was 29.5 months in NAVIGATOR and 3.4 months in Study 1002. CONCLUSIONS: In this indirect, retrospective analysis, avapritinib demonstrated more durable survival outcomes compared with other TKIs in patients with unresectable/metastatic PDGFRA D842V-mutant GIST. TRIAL REGISTRATION: The NAVIGATOR trial was registered at ClinicalTrials.gov as per July 2015, Identifier: NCT02508532 .

Ripretinib in patients with advanced gastrointestinal stromal tumours (INVICTUS): a double-blind, randomised, placebo-controlled, phase 3 trial.

BACKGROUND: Resistance to approved inhibitors of KIT proto-oncogene, receptor tyrosine kinase (KIT), and platelet-derived growth factor receptor α (PDGFRA) is a clinical challenge for patients with advanced gastrointestinal stromal tumours. We compared the efficacy and safety of ripretinib, a switch-control tyrosine kinase inhibitor active against a broad spectrum of KIT and PDGFRA mutations, with placebo in patients with previously treated, advanced gastrointestinal stromal tumours. METHODS: In this double-blind, randomised, placebo-controlled, phase 3 study, we enrolled adult patients in 29 specialised hospitals in 12 countries. We included patients aged 18 years or older who had advanced gastrointestinal stromal tumours with progression on at least imatinib, sunitinib, and regorafenib or documented intolerance to any of these treatments despite dose modifications, and who had an Eastern Cooperative Oncology Group (ECOG) performance status of 0-2. Eligible patients were randomly assigned (2:1) to receive either oral ripretinib 150 mg once daily (ripretenib group) or placebo once daily (placebo group). Randomisation was done via an interactive response system using randomly permuted block sizes of six and stratified according to number of previous therapies and ECOG performance status. Patients, investigators, research staff, and the sponsor study team were masked to a patient's treatment allocation until the blinded independent central review (BICR) showed progressive disease for the patient. The primary endpoint was progression-free survival, assessed by BICR. The primary analysis was done in the intention-to-treat population and safety was assessed in patients who received at least one dose of study drug. Patients randomly assigned to placebo were permitted to cross over to ripretinib 150 mg at the time of disease progression. The INVICTUS study is registered with ClinicalTrials.gov, number NCT03353753, and with WHO International Clinical Trials Registry Platform, number EUCTR2017-002446-76-ES; follow-up is ongoing. FINDINGS: Between Feb 27, 2018, and Nov 16, 2018, 129 of 154 assessed patients were randomly assigned to receive either ripretinib (n=85) or placebo (n=44). At data cutoff (May 31, 2019), at a median follow-up of 6·3 months (IQR 3·2-8·2) in the ripretinib group and 1·6 months (1·1-2·7) in the placebo group, 51 patients in the ripretinib group and 37 in the placebo group had had progression-free survival events. In the double-blind period, median progression-free survival was 6·3 months (95% CI 4·6-6·9) with ripretinib compared with 1·0 months (0·9-1·7) with placebo (hazard ratio 0·15, 95% CI 0·09-0·25; p<0·0001). The most common (>2%) grade 3 or 4 treatment-related treatment-emergent adverse events in the ripretinib group (n=85) included lipase increase (four [5%]), hypertension (three [4%]), fatigue (two [2%]), and hypophosphataemia (two (2%]); in the placebo group (n=43), the most common (>2%) grade 3 or 4 treatment-related treatment-emergent adverse events were anaemia (three [7%]), fatigue (one [2%]), diarrhoea (one [2%]), decreased appetite (one [2%]), dehydration (one [2%]), hyperkalaemia (one [2%]), acute kidney injury (one [2%]), and pulmonary oedema (one [2%]). Treatment-related serious adverse events were reported in eight (9%) of 85 patients who received ripretinib and three (7%) of 43 patients who received placebo. Treatment-related deaths occurred in one patient in the placebo group (septic shock and pulmonary oedema) and one patient in the ripretinib group (cause of death unknown; the patient died during sleep). INTERPRETATION: Ripretinib significantly improved median progression-free survival compared with placebo and had an acceptable safety profile in patients with advanced gastrointestinal stromal tumours who were resistant to approved treatments. FUNDING: Deciphera Pharmaceuticals.

Avapritinib in advanced PDGFRA D842V-mutant gastrointestinal stromal tumour (NAVIGATOR): a multicentre, open-label, phase 1 trial.

BACKGROUND: Targeting of KIT and PDGFRA with imatinib revolutionised treatment in gastrointestinal stromal tumour; however, PDGFRA Asp842Val (D842V)-mutated gastrointestinal stromal tumour is highly resistant to tyrosine kinase inhibitors. We aimed to assess the safety, tolerability, and antitumour activity of avapritinib, a novel KIT and PDGFRA inhibitor that potently inhibits PDGFRA D842V, in patients with advanced gastrointestinal stromal tumours, including patients with KIT and PDGFRA D842V-mutant gastrointestinal stromal tumours (NAVIGATOR). METHODS: NAVIGATOR is a two-part, open-label, dose-escalation and dose-expansion, phase 1 study done at 17 sites across nine countries (Belgium, France, Germany, Poland, Netherlands, South Korea, Spain, the UK, and the USA). Patients aged 18 years or older, with an Eastern Cooperative Oncology Group performance status of 2 or less, and with adequate end-organ function were eligible to participate. The dose-escalation part of the study included patients with unresectable gastrointestinal stromal tumours. The dose-expansion part of the study included patients with an unresectable PDGFRA D842V-mutant gastrointestinal stromal tumour regardless of previous therapy or gastrointestinal stromal tumour with other mutations that either progressed on imatinib and one or more tyrosine kinase inhibitor, or only received imatinib previously. On the basis of enrolment trends, ongoing review of study data, and evolving knowledge regarding the gastrointestinal stromal tumour treatment paradigm, it was decided by the sponsor's medical director together with the investigators that patients with PDGFRA D842V mutations would be analysed separately; the results from this group of patients is reported in this Article. Oral avapritinib was administered once daily in the dose-escalation part (starting dose of 30 mg, with increasing dose levels once daily in continuous 28-day cycles until the maximum tolerated dose or recommended phase 2 dose was determined; in the dose-expansion part, the starting dose was the maximum tolerated dose from the dose-escalation part). Primary endpoints were maximum tolerated dose, recommended phase 2 dose, and safety in the dose-escalation part, and overall response and safety in the dose-expansion part. Safety was assessed in all patients from the dose-escalation part and all patients with PDGFRA D842V-mutant gastrointestinal stromal tumour in the dose-expansion part, and activity was assessed in all patients with PDGFRA D842V-mutant gastrointestinal stromal tumour who received avapritinib and who had at least one target lesion and at least one post-baseline disease assessment by central radiology. This study is registered with ClinicalTrials.gov, NCT02508532. FINDINGS: Between Oct 26, 2015, and Nov 16, 2018 (data cutoff), 46 patients were enrolled in the dose-escalation part, including 20 patients with a PDGFRA D842V-mutant gastrointestinal stromal tumour, and 36 patients with a PDGFRA D842V-mutant gastrointestinal stromal tumour were enrolled in the dose-expansion part. At data cutoff (Nov 16, 2018), 38 (46%) of 82 patients in the safety population (median follow-up of 19·1 months [IQR 9·2-25·5]) and 37 (66%) of the 56 patients in the PDGFRA D842V population (median follow-up of 15·9 months [IQR 9·2-24·9]) remained on treatment. The maximum tolerated dose was 400 mg, and the recommended phase 2 dose was 300 mg. In the safety population (patients with PDGFRA D842V-mutant gastrointestinal stromal tumour from the dose-escalation and dose-expansion parts, all doses), treatment-related grade 3-4 events occurred in 47 (57%) of 82 patients, the most common being anaemia (14 [17%]); there were no treatment-related deaths. In the PDGFRA D842V-mutant population, 49 (88%; 95% CI 76-95) of 56 patients had an overall response, with five (9%) complete responses and 44 (79%) partial responses. No dose-limiting toxicities were observed at doses of 30-400 mg per day. At 600 mg, two patients had dose-limiting toxicities (grade 2 hypertension, dermatitis acneiform, and memory impairment in patient 1, and grade 2 hyperbilirubinaemia in patient 2). INTERPRETATION: Avapritinib has a manageable safety profile and has preliminary antitumour activity in patients with advanced PDGFRA D842V-mutant gastrointestinal stromal tumours. FUNDING: Blueprint Medicines.

NCCN Guidelines Insights: Soft Tissue Sarcoma, Version 1.2021.

The NCCN Guidelines for Soft Tissue Sarcoma provide recommendations for the diagnosis, evaluation, treatment, and follow-up for patients with soft tissue sarcomas. These NCCN Guidelines Insights summarize the panel discussion behind recent important updates to the guidelines, including the development of a separate and distinct guideline for gastrointestinal stromal tumors (GISTs); reconception of the management of desmoid tumors; inclusion of further recommendations for the diagnosis and management of extremity/body wall, head/neck sarcomas, and retroperitoneal sarcomas; modification and addition of systemic therapy regimens for sarcoma subtypes; and revision of the principles of radiation therapy for soft tissue sarcomas.

Treatment Patterns and Distance to Treatment Facility for Soft Tissue Sarcoma of the Extremity.

BACKGROUND: The impact that distance traveled to receive treatment has on treatments and outcomes among patients with soft tissue sarcoma (STS) of the extremity has yet to be thoroughly investigated. METHODS: Information on patients treated for STS of the extremity between 2006 and 2015 was obtained from the National Cancer Database. Patients were stratified into two groups based on median distance traveled to receive treatment. Chi-square tests assessed associations between categorical variables and distance to treatment. Kaplan-Meier survival estimates and Cox regression were used to estimate survival. RESULTS: The sample included 21,763 patients. The mean age was 59.3 y, 54.6% were men, and 83.2% were white. The median distance traveled to the treating facility was 15.6 miles. Compared with patients who traveled <15 miles, those who traveled ≥15 miles were more likely to have undifferentiated rather than well-differentiated tumors (odds ratio [OR], 1.23; 95% confidence interval [95% CI], 1.10-1.37), and stage II rather than stage I disease (OR, 1.14; 95% CI, 1.04-1.24). They were also more likely to undergo limb-sparing resection (OR, 1.58; 95% CI, 1.39-1.79) or amputation (OR, 1.72; 95% CI, 1.44-2.07) rather than no surgery and less likely to have positive margins (OR, 0.86; 95% CI, 0.79-0.93). There was no difference in the risk of death between patients who traveled ≥15 miles and those who did not (hazard ratio, 1.00; 95% CI, 0.94-1.07). CONCLUSIONS: Although clinical characteristics and treatments may differ based on distance traveled, survival appears equivalent. Further research into reasons why greater distance traveled is associated with more advanced disease, but comparable survival is warranted.

Safety and efficacy of trabectedin when administered in the inpatient versus outpatient setting: Clinical considerations for outpatient administration of trabectedin.

BACKGROUND: The results of the randomized, phase 3 ET743-SAR-3007 trial demonstrated that trabectedin had a significantly longer progression-free survival (PFS) compared with dacarbazine in patients with advanced leiomyosarcoma/liposarcoma after the failure of prior chemotherapy. Patients randomized to trabectedin received a 24-hour intravenous infusion either in an inpatient or outpatient setting. Herein, the authors reported the safety, efficacy, and patient-reported outcomes based on first infusion site of care. METHODS: Patients were randomized 2:1 to trabectedin (at a dose of 1.5 mg/m2 ) or dacarbazine (1 g/m2 over 20-120 minutes) with overall survival (OS) as the primary endpoint and PFS, time to disease progression, objective response rate, duration of response, safety, and patient-reported symptom scoring as secondary endpoints. The setting of the trabectedin infusion was based on institutional preference and categorized based on the setting of the first infusion. RESULTS: Of the 378 patients who were treated with trabectedin, 100 (27%) and 277 (73%), respectively, first received trabectedin in the inpatient and outpatient setting. No differences were observed with regard to PFS or OS based on site of care. The median PFS was 4.1 months versus 4.2 months (hazard ratio, 0.90; P = .49) for inpatients versus outpatients, respectively, and the median OS was 14.3 months versus 13.7 months (hazard ratio, 0.89; P = .40), respectively. Grade 3/4 adverse events (classified according to the National Cancer Institute Common Terminology Criteria for Adverse Events [version 4.0]) were reported in 87 inpatients (87%) compared with 219 outpatients (79%); grade 3/4 serious adverse events were reported in 43 inpatients (43%) and 92 outpatients (33%). Extravasation occurred in 0 inpatients and 5 outpatients (2%), whereas the incidence of catheter-related complications was similar between groups (16% vs 15%). CONCLUSIONS: Although the majority of patients who were randomized to trabectedin received outpatient therapy, the outcomes of the current study suggested equivalent safety and efficacy in either setting.

Overall survival and histology-specific subgroup analyses from a phase 3, randomized controlled study of trabectedin or dacarbazine in patients with advanced liposarcoma or leiomyosarcoma.

BACKGROUND: We performed a randomized phase 3 study of trabectedin versus dacarbazine in previously-treated patients with liposarcoma/leiomyosarcoma (LPS/LMS). METHODS: Patients were randomized 2:1 to trabectedin (n = 384) or dacarbazine (n = 193) administered intravenously every 3 weeks. The primary objective was overall survival (OS). Secondary objectives were progression-free survival, objective response rate, safety, and patient-reported outcomes, all previously reported and demonstrating superior disease control with trabectedin. Results of the final OS analysis in preplanned subgroups of patients with LPS/LMS are presented. RESULTS: At the time of the final OS analysis, 577 patients had been assigned randomly, including 423 (73%) with LMS and 154 (27%) with LPS. The median duration of treatment exposure was higher in the trabectedin arm compared with the dacarbazine arm (4 vs 2 cycles), as was the proportion of patients receiving an extended number of therapy courses (≥6 cycles: 42% vs 22%). This pattern was consistent across histological subgroups: the median number of treatment cycles (4 vs 2 for both subgroups) and proportion of patients with ≥6 treatment cycles (LMS, 43% vs 24%; LPS, 40% vs 16%). Despite improved disease control by trabectedin, no improvement in OS was observed; the final median OS for trabectedin versus dacarbazine was 13.7 versus 13.1 months (P = .49). Sensitivity analyses of OS suggest confounding by post-study anticancer therapies, which were utilized in most patients in both treatment arms (71% vs 69%, respectively). CONCLUSION: The final OS results demonstrated comparable survival between LPS/LMS patients receiving trabectedin or dacarbazine, which is consistent with the interim analysis results. Both LPS and LMS demonstrated improved disease control with trabectedin.

Retroperitoneal Sarcomas: Does Laterality Matter?

BACKGROUND: Sarcomas are malignant tumors of connective tissue that can vary widely in etiology. Parameters such as grade, extent of resection, and tumor integrity have been shown to affect prognosis. Our principal aim was to examine associations between the laterality of retroperitoneal sarcomas and tumor characteristics, treatment, and patient outcomes. MATERIALS AND METHODS: We performed a retrospective study of patients treated at our tertiary referral center with a diagnosis of primary retroperitoneal sarcoma who underwent tumor resection. Categorical variables were compared using the chi-square test, whereas continuous variables were compared using one-way analysis of variance. Cox regression was used to estimate the risk of death. RESULTS: Data from 106 patients were analyzed. A greater proportion of bilateral or midline tumors were leiomyosarcomas (P = 0.02), whereas right-sided tumors were more likely to be liposarcoma (P = 0.02). There was no significant relationship between laterality and tumor grade or stage. Two-thirds of patients had at least one contiguous organ resected (n = 68, 65.4%). Patients with nephrectomy during sarcoma resection were more likely to have right-sided disease (P = 0.02). Splenectomy and pancreatectomy were associated with left-sided disease (P < 0.01; P < 0.01), and pancreaticoduodenectomies with bilateral or midline disease (P < 0.001). Adjusting for age, sex, race, grade, stage, histology, and treatment, there was no increased risk of death or recurrence based on laterality. CONCLUSIONS: Although laterality did not seem to have a measurable relationship with patient outcomes or survival, there was a significant association between laterality, tumor histology, and resection of contiguous organs. These preliminary findings warrant further investigation.