A CT-based radiomics classification model for the prediction of histological type and tumour grade in retroperitoneal sarcoma (RADSARC-R): a retrospective multicohort analysis.

BACKGROUND: Retroperitoneal sarcomas are tumours with a poor prognosis. Upfront characterisation of the tumour is difficult, and under-grading is common. Radiomics has the potential to non-invasively characterise the so-called radiological phenotype of tumours. We aimed to develop and independently validate a CT-based radiomics classification model for the prediction of histological type and grade in retroperitoneal leiomyosarcoma and liposarcoma. METHODS: A retrospective discovery cohort was collated at our centre (Royal Marsden Hospital, London, UK) and an independent validation cohort comprising patients recruited in the phase 3 STRASS study of neoadjuvant radiotherapy in retroperitoneal sarcoma. Patients aged older than 18 years with confirmed primary leiomyosarcoma or liposarcoma proceeding to surgical resection with available contrast-enhanced CT scans were included. Using the discovery dataset, a CT-based radiomics workflow was developed, including manual delineation, sub-segmentation, feature extraction, and predictive model building. Separate probabilistic classifiers for the prediction of histological type and low versus intermediate or high grade tumour types were built and tested. Independent validation was then performed. The primary objective of the study was to develop radiomic classification models for the prediction of retroperitoneal leiomyosarcoma and liposarcoma type and histological grade. FINDINGS: 170 patients recruited between Oct 30, 2016, and Dec 23, 2020, were eligible in the discovery cohort and 89 patients recruited between Jan 18, 2012, and April 10, 2017, were eligible in the validation cohort. In the discovery cohort, the median age was 63 years (range 27-89), with 83 (49%) female and 87 (51%) male patients. In the validation cohort, median age was 59 years (range 33-77), with 46 (52%) female and 43 (48%) male patients. The highest performing model for the prediction of histological type had an area under the receiver operator curve (AUROC) of 0·928 on validation, based on a feature set of radiomics and approximate radiomic volume fraction. The highest performing model for the prediction of histological grade had an AUROC of 0·882 on validation, based on a radiomics feature set. INTERPRETATION: Our validated radiomics model can predict the histological type and grade of retroperitoneal sarcomas with excellent performance. This could have important implications for improving diagnosis and risk stratification in retroperitoneal sarcomas. FUNDING: Wellcome Trust, European Organisation for Research and Treatment of Cancer-Soft Tissue and Bone Sarcoma Group, the National Institutes for Health, and the National Institute for Health and Care Research Biomedical Research Centre at The Royal Marsden NHS Foundation Trust and The Institute of Cancer Research.

Exploratory analysis of tumor imaging in a Phase 2 trial with cabozantinib in gastrointestinal stromal tumor: lessons learned from study EORTC STBSG 1317 'CaboGIST'.

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are malignant mesenchymal tumors arising in the gastrointestinal tract. Their systemic treatment is based on the use of tyrosine kinase inhibitors (TKIs) with imatinib, sunitinib, and regorafenib being the preferred agents. Assessment of tumor response to TKI treatment in GISTs is traditionally done according the Response Evaluation Criteria in Solid Tumors (RECIST), while Choi criteria have also been proposed as alternative tool assessing both volumetric and density changes on computer tomography (CT) scans. EORTC STBSG 1317 'CaboGIST' was a single-arm prospective Phase 2 trial which met its primary endpoint, as 60% of patients previously treated with imatinib and sunitinib were progression-free at 12 weeks (95% CI 45-74%) based on local RECIST assessment. MATERIALS AND METHODS: We report here an exploratory analysis of local versus central RECIST version 1.1 assessment and a comparison of RECIST version 1.1 versus Choi criteria. RESULTS: Comparisons between local and central RECIST version 1.1 at week 12 revealed discrepancies in 17/43 evaluable cases (39.5%). When comparing Choi with local and central RECIST version 1.1, discrepancies were observed in 27/43 (62.8%) and 21/43 (48.8%) cases, respectively. A total of 68% of evaluable patients were progression-free and alive at week 12 based on local RECIST, 84% according to central RECIST analysis and 81% when applying Choi criteria. Central assessment upgraded the treatment response both with RECIST version 1.1 and Choi. CONCLUSIONS: The results of this exploratory analysis support the conclusion that cabozantinib is active in patients with metastatic or recurrent GIST after treatment with imatinib and sunitinib and confirm once again the limitations of RECIST to capture response to TKI in GIST, and the importance to include density changes in the response evaluation in this setting. Clinical trial number: EORTC 1317, NCT02216578.

Long-term efficacy update of crizotinib in patients with advanced, inoperable inflammatory myofibroblastic tumour from EORTC trial 90101 CREATE.

PURPOSE: European Organisation for Research and Treatment of Cancer (EORTC) 90101 (CREATE) was a prospective, multicentric, non-randomised, open-label phase II basket trial to assess the efficacy and safety of crizotinib in patients with different types of cancers, including advanced inflammatory myofibroblastic tumour (IMT) with or without anaplastic lymphoma kinase (ALK) rearrangements. Here, we report updated results with long-term follow-up. PATIENTS/METHODS: After central reference pathology, eligible ALK-positive and ALK-negative patients with advanced/metastatic IMT deemed incurable with surgery, radiotherapy or systemic therapy received oral crizotinib 250 mg twice daily. The ALK status was assessed centrally using immunohistochemistry and fluorescence in situ hybridisation. The primary end-point was the proportion of patients who achieved an objective response (i.e. complete or partial response). If ≥6 ALK-positive patients achieved a confirmed response, the trial would be deemed successful. RESULTS: At data cut-off on 28th January 2021, we performed the final analysis of this trial. Of the 20 eligible and treated patients (19 of whom were evaluable for efficacy), with a median follow-up of 50 months, five were still on crizotinib treatment (4/12 ALK-positive and 1/8 ALK-negative patients). The updated objective response rate (ORR) was 66.7% (95% confidence interval [CI] 34.9-90.1%) in ALK-positive patients and 14.3% (95% CI 0.0-57.9%) in ALK-negative patients. In the ALK-positive and ALK-negative patients, the median progression-free survival was 18.0 months (95% CI 4.0-NE) and 14.3 months (95% CI 1.2-31.1), respectively; 3-year overall survival rates were 83.3% (95% CI 48.2-95.6) and 34.3% (95% CI 4.8-68.5). Safety results were consistent with previously reported data. CONCLUSION: These updated results confirm previous findings that crizotinib is effective, with durable responses, in patients with locally advanced or metastatic ALK-positive IMT. With further follow-up after the original primary analysis, the ORR increased, as patients derived long-term benefit and some responses converted from stable disease to partial responses. CLINICAL TRIAL NUMBER: EORTC 90101, NCT01524926.

Activity and safety of the multi-target tyrosine kinase inhibitor cabozantinib in patients with metastatic gastrointestinal stromal tumour after treatment with imatinib and sunitinib: European Organisation for Research and Treatment of Cancer phase II trial 1317 'CaboGIST'.

BACKGROUND: Gastrointestinal stromal tumour (GIST) is commonly treated with tyrosine kinase inhibitors (TKIs), but most patients ultimately develop secondary resistance. Cabozantinib, a multi-targeted TKI inhibitor, has activity in patient-derived GIST mouse xenograft models and can overcome compensatory MET signalling occurring on TKI treatment. European Organisation for Treatment of Cancer (EORTC) 1317 'CaboGIST' assessed the safety and activity of cabozantinib in patients with GIST who had progressed on imatinib and sunitinib. METHODS: In this multi-center, open label, single arm phase II study, eligible GIST patients received oral cabozantinib (60 mg) once daily. Primary end-point was the progression-free survival rate at 12 weeks assessed by the local investigator per Response Evaluation Criteria in Solid Tumours 1·1. If at least 21 of the first 41 eligible and evaluable patients were progression-free at week 12, the activity of cabozantinib was sufficient to warrant further exploration according to the A'Hern one-stage study design. FINDINGS: A total of 50 eligible patients started treatment between 02/2017 and 08/2018, including four (8%) still continuing cabozantinib at clinical cut-off (09/2019). The number of 3-weekly treatment cycles ranged from 1 to 30. Among the first 41 eligible and evaluable patients, 24 were progression-free at week 12 (58·5%, 95% confidence interval [CI] 42·0-74·0%). Among all 50 patients, 30 were progression-free at week 12 (60%, 95% CI 45-74%). Seven patients achieved a partial response (14%, 95% CI 6-27%), and 34 had stable disease (68%, 95% CI 53-80%) as best response. Progression was seen in eight patients (16%, 95% CI 7-29%), and one was not evaluable. Disease control was achieved in 41 patients (82%, 95% CI 69-91%). Median progression-free survival was 5·5 months (95% CI 3·6-6·9). The most common adverse events were diarrhoea (76%), palmar-plantar erythrodysesthesia syndrome (60%), fatigue (50%), hypertension (42%), weight loss (40%) and oral mucositis (30%), with 32 (64%) patients requiring dose reductions, 27 (54%) having treatment interruptions and no cabozantinib-related deaths observed. INTERPRETATION: EORTC 1317 met its primary end-point, with 24/41 patients being progression-free at week 12 of treatment. The objective response was 14% with an encouraging disease control rate of 82%. Results of this trial confirm preclinical findings and warrant further exploration of cabozantinib in GIST. CLINICAL TRIAL NUMBERS: EORTC 1317, NCT02216578, EudraCT 2014-000501-13.

Crizotinib in patients with advanced, inoperable inflammatory myofibroblastic tumours with and without anaplastic lymphoma kinase gene alterations (European Organisation for Research and Treatment of Cancer 90101 CREATE): a multicentre, single-drug, prospective, non-randomised phase 2 trial.

BACKGROUND: An inflammatory myofibroblastic tumour (IMFT) is a rare mesenchymal neoplasm characterised by anaplastic lymphoma kinase (ALK) gene rearrangements. We assessed the activity and safety of crizotinib, a tyrosine kinase inhibitor, targeting ALK in patients with advanced IMFT either with or without ALK alterations. METHODS: We did a multicentre, biomarker-driven, single-drug, non-randomised, open-label, two-stage phase 2 trial (European Organisation for Research and Treatment of Cancer 90101 CREATE) at 13 study sites (five university hospitals and eight specialty clinics) in eight European countries (Belgium, France, Germany, Italy, Netherlands, Poland, Slovakia, and the UK). Eligible participants were patients aged at least 15 years with a local diagnosis of advanced or metastatic IMFT deemed incurable with surgery, radiotherapy, or systemic therapy; measurable disease; an Eastern Cooperative Oncology Group performance status of 0-2; and adequate haematological, renal, and liver function. Central reference pathology was done for confirmation of the diagnosis, and ALK positivity or negativity was assessed centrally using immunohistochemistry and fluorescence in-situ hybridisation based on archival tumour tissue and defined as ALK immunopositivity or rearrangements in at least 15% of tumour cells. Eligible ALK-positive and ALK-negative patients received oral crizotinib 250 mg twice per day administered on a continuous daily dosing schedule (the duration of each treatment cycle was 21 days) until documented disease progression, unacceptable toxicity, or patient refusal. If at least two of the first 12 eligible and assessable ALK-positive patients achieved a confirmed complete or partial response according to Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, a maximum of 35 patients were to be enrolled. If at least six ALK-positive patients achieved a confirmed response, the trial would be deemed successful. The primary endpoint was the proportion of patients who achieved an objective response (ie, a complete or partial response) as per RECIST 1.1, with response confirmation assessed by the local investigator every other cycle. Activity and safety endpoints were analysed in the per-protocol population. This trial is registered with ClinicalTrials.gov, number NCT01524926. FINDINGS: Between Oct 3, 2012, and April 12, 2017, we recruited and treated 20 eligible participants, 19 of whom were assessable for the primary endpoint. Median follow-up was 863 days (IQR 358-1304). Six of 12 ALK-positive patients (50%, 95% CI 21·1-78·9) and one of seven ALK-negative patients (14%, 0·0-57·9) achieved an objective response. The most common treatment-related adverse events in the 20 participants were nausea (11 [55%]), fatigue (9 [45%]), blurred vision (nine [45%]), vomiting (seven [35%]), and diarrhoea (seven [35%]). Eight serious adverse events occurred in five patients: pneumonia, fever of unknown cause, a heart attack with increased creatinine and possible sepsis, an abdominal abscess with acute renal insufficiency, and a QT prolongation. INTERPRETATION: With 50% of participants with ALK-positive tumours achieving an objective response, crizotinib met the prespecified criteria for success in this trial. The results presented here support the rationale for inhibiting ALK in patients with IMFT. Crizotinib could be considered as the standard of care for patients with locally advanced or metastatic ALK-positive IMFT who do not qualify for curative surgery. FUNDING: The European Organisation for Research and Treatment of Cancer and Pfizer.

The tyrosine kinase inhibitor crizotinib does not have clinically meaningful activity in heavily pre-treated patients with advanced alveolar rhabdomyosarcoma with FOXO rearrangement: European Organisation for Research and Treatment of Cancer phase 2 trial 90101 'CREATE'.

BACKGROUND: Alveolar rhabdomyosarcomas (ARMSs) can harbour MET and anaplastic lymphoma kinase (ALK) alterations. We prospectively assessed crizotinib in patients with advanced/metastatic ARMS. METHODS: Eligible patients with a central diagnosis of ARMS received oral crizotinib 250 mg twice daily. Patients were attributed to MET/ALK+ or MET/ALK- subcohorts by assessing the presence or absence of the forkhead box O1 (FOXO1; a marker of MET upregulation) and/or ALK gene rearrangement. The primary end-point was the objective response rate (ORR). Secondary end-points included duration of response (DOR), disease control rate (DCR), progression-free survival (PFS), progression-free rate (PFR), overall survival (OS) and safety. FINDINGS: Nineteen of 20 consenting patients had centrally confirmed ARMS. Molecular assessment revealed rearrangement of FOXO1 in 17 tumours and ALK in none. Thirteen eligible patients were treated, but only eight were evaluable for the primary end-point because of the observed aggressiveness of the disease. Among seven evaluable MET+/ALK- patients, only one achieved a confirmed partial response (ORR: 14.3%; 95% confidence interval [CI]: 0.3-57.8) with a DOR of 52 d. Further MET+/ALK- efficacy end-points were DCR: 14.3% (95% CI: 0.3-57.8), median PFS: 1.3 months (95% CI: 0.5-1.5) and median OS: 5.6 months (95% CI: 0.7-7.0). The remaining MET+/ALK- and MET-/ALK- patients had early progression as best response. Common treatment-related adverse events were fatigue (5/13 [38.5%]), nausea (4/13 [30.8%]), anorexia (4/13 [30.8%]), vomiting (2/13 [15.4%]) and constipation (2/13 [15.4%]). All 13 treated patients died early because of progressive disease. INTERPRETATION: Crizotinib is well tolerated but lacks clinically meaningful activity as a single agent in patients with advanced metastatic ARMS. Assessing single agents in aggressive, chemotherapy-refractory ARMS is challenging, and future trials should explore established chemotherapy ± investigational compounds in earlier lines of treatment. CLINICAL TRIAL NUMBER: EORTC 90101, ClinicalTrials.gov NCT01524926.

Identification of microRNA biomarkers for response of advanced soft tissue sarcomas to eribulin: Translational results of the EORTC 62052 trial.

BACKGROUND: Recent phase II and III clinical trials demonstrated anti-tumour activity of eribulin, a tubulin-interacting cytotoxic agent, in patients with metastatic soft tissue sarcoma (STS). In this exploratory study, we aimed to identify putative microRNA biomarkers that associate with eribulin sensitivity or resistance in STS. MATERIALS AND METHODS: Archival tumour tissue from primary tumours or metastatic lesions was collected prior to eribulin treatment, from 65 consenting patients involved in the EORTC trial 62052. This phase II study (ClinicalTrials.gov identifier NCT00413192) included multiple subtypes of STS. Tissue was available from 21 leiomyosarcomas, 14 adipocytic sarcomas, 9 synovial sarcomas and 21 other sarcoma histotypes. Total RNA was isolated from formalin-fixed, paraffin-embedded tumour samples and analysed using Taqman® Low Density Arrays to determine microRNA expression profiles. The expression of a total of 756 microRNAs was assessed. Progression-free survival at week 12 (RECIST 1.0) measured as a binary variable, was the primary end-point of the clinical trial and used as a primary response measure for correlative studies. Seventeen of 53 (32.1%) evaluable patients in the analysed subset had non-progressive disease at week 12 and were defined as responders. RESULTS: The expression of 26 individual microRNAs (p < 0.05) differed significantly between non-responders and responders. Additional microRNAs of potential relevance were identified when considering the different histological subgroups. CONCLUSIONS: The expression level of particular microRNAs in STS tissue samples may predict response to eribulin. Further validation studies as well as a preclinical assessment of the underlying molecular mechanisms are required.