Gastrointestinal stromal tumors (GIST) mutational status is recognized factor related to the results of tyrosine kinase inhibitors therapy such as imatinib (IM) or sunitinib (SU). Arterial ...hypertension (AH) is common adverse event related to SU, reported as predictive factor in renal cell carcinoma. The aim of the study was to analyze the outcomes and factors predicting results of SU therapy in inoperable/metastatic CD117(+) GIST patients after IM failure.
We identified 137 consecutive patients with advanced inoperable/metastatic GIST treated in one center with SU (2nd line treatment). Median follow-up time was 23 months. Additionally, in 39 patients there were analyzed selected constitutive single nucleotide polymorphisms (SNPs) of VEGFA and VEGFR2 genes.
One year progression-free survival (PFS; calculated from the start of SU) rate was 42% and median PFS was 43 weeks. The estimated overall survival (OS, calculated both from start of SU or IM) was 74 weeks and 51 months, respectively. One-year PFS was 65% (median 74 weeks) in 55 patients with AH vs. 22% (median 17 weeks) in patients without AH. Patients with primary tumors carrying mutations in KIT exon 9 or wild-type had substantially better 1-year PFS (68% and 57%; median 65.5 and 50.5 weeks, respectively) than patients having tumors with KIT exon 11 or PDGFRA mutations (34% and 15%; median 36.8 and 9 weeks, respectively). We identified two independent factors with significant impact on PFS and OS in univariate and multivariate analysis: primary tumor genotype and presence of AH. The most common adverse events during therapy were: fatigue, AH, hypothyroidism, hand and foot syndrome, mucositis, skin reactions, dyspepsia, and diarrhea. Two deaths were assessed as related to tumor rupture caused by reaction to SU therapy. The presence of C-allele in rs833061 and the T-allele in rs3025039 polymorphism of VEGFA were associated with significantly higher risk of hypothyroidism (OR: 10.0 p = 0.041 and OR: 10.5; p = 0.015, respectively).
We confirmed that many advanced GIST patients benefit from SU therapy with OS > 1.5 year. Primary tumor KIT/PDGFRA genotype and SU-induced AH, as surrogate of its antiangiogenic activity are two independent factors influencing both PFS and OS.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The real-world data on adjuvant imatinib therapy in high-risk primary GIST are scarce.
We have analysed the data of 107 consecutive patients with gastrointestinal stromal tumour (GIST) after ...resection treated with adjuvant imatinib (for planned 3 years with initial dose 400 mg daily, started not later than 4 months after operation) in 6 oncological centres in 2013–2018. All patients were required to have high risk of recurrence (at least 50% according to NCCN/AFIP criteria), known mutational status to exclude PDGFRA D842V mutants and KIT/PDGFRA-wild type cases from therapy without any further selection. Median follow-up time was 27 months.
The most common primary localization of GIST was small bowel (63 patients; 59%), followed by the stomach (40 patients; 37%). The majority of GIST cases harboured exon 11 KIT mutations (88 cases, 82%), 11 cases had exon 9 KIT mutations (10%), 8 had other KIT/PDGFRA mutations potentially sensitive to imatinib. Forty patients (37%) finished 3-year adjuvant imatinib therapy as planned, 48 (45%) still continue therapy, 5 (4.5%) patients had finished adjuvant therapy prematurely due to toxicity, 6 (6%) due to disease progression on treatment and 8 (7.5%) due to other reasons. The disease relapse was detected in 19 patients, of them in 5 cases in exon 9 KIT mutants (45%), and 14 cases in patients with exon 11 KIT mutations (11%) p < 0.01. Estimated 4-year relapse-free survival (RFS) rate is 78%.
The early results of adjuvant therapy with imatinib in routine practice outside clinical trials in high-risk mutation-driven GIST patients only confirm high efficacy of this therapy with better tolerability than in clinical trials. We found overrepresentation of exon 9 KIT mutants and ruptured tumors in a group of patients with disease relapse.
The first real world data confirming efficacy of 3-year adjuvant therapy with imatinib in patients with high-risk molecular profiled gastrointestinal stromal tumors, especially harboring KIT exon 11 mutations.
To assess the outcomes of radiotherapy, in terms of local control and treatment complications, of advanced or difficult giant cell tumors of bone (GCTB) that could not be treated by surgery.
Among ...122 consecutive patients with confirmed GCTB from 1985 to 2007, 77 patients were treated by megavoltage radiotherapy because they were inappropriate candidates for surgery. We have performed analysis of all data in terms of progression-free survival (PFS) and treatment morbidity. Median follow-up time was 58 months.
In the irradiated group, maximal tumor size ranged from 5 to 18 cm (median, 8.5). Anatomic distribution was as follows: femur, 27 cases; tibia, 19; radial/ulnar bone, 12; sacrum, 9; pelvic bones, 5; other, 5. Twenty-one patients (27%) were referred for local recurrence after ≥1 other treatment procedures. The radiation doses ranged from 26 to 89 Gy (median, 56; administered 1.8-2.0 Gy/fraction with average total duration of treatment of 5-7 weeks); 8 patients (10%) received <50 Gy. All patients tolerated treatment well without acute or late complications. All patients except two are alive. Local control was achieved in 65 patients (84%; bone recalcification/restitution of joint functions), 12 patients showed signs of local progression, all within irradiated fields (9 were treated successfully with salvage surgery). Five- and 10-year local PFS were 83% and 73%, respectively. Three patients developed lungs metastases. Malignant transformation of GCTB occurred in two patients.
GCTB can be safely and effectively treated with megavoltage radiotherapy with local control rate >80% at 5 years. Our study confirms that radiotherapy of GCTB offers an alternative to difficult or complex surgery and may be an option of choice in the treatment of inoperable patients.
The aim of the study was to analyze the treatment results of advanced GIST in the largest, homogenous series of older patients.
Between 2001 and 2016, 686 patients with metastatic/unresectable GIST ...were treated initially with imatinib and 656 were included in the analysis. Subsequently 232 patients were treated with sunitinib after imatinib failure. We have analyzed the outcomes of patients who have been treated with the tyrosine kinase inhibitor at the age ≥ 70 years and compared to control group of patients younger than 70 years old.
In the group of patients treated with imatinib, 139 (21%) started therapy at the age of at least 70 years (median age of the entire cohort: 60). Median progression-free survival (PFS) on 1st line imatinib did not differ between patients ≥70 yo (years old) and < 70yo (38.5 vs 44.9 months), but median overall survival (OS) was significantly better for younger patients (81 months vs. 50; p = 0.0001; although disease-specific survival - DSS was similar). Distribution of primary tumor mutational status was generally similar in older and younger patients. Permanent dose reduction (300–100 mg/day) was required for 23 patients (16.9%) in the older group and was significantly more frequent as compared to younger patients (5%). Drug-related adverse events were mainly of grades 1/2, but grade 3/4 toxicity occurred more frequently in older (14.7%) than in younger patients (3.8%). Similarly in group of patients treated with second-line sunitinib median PFS and DSS were comparable in groups of patients ≥70 yo (n = 55) and < 70yo (9.7 months vs 10.3 months; p = 0.7, and 21.5 vs 22.9 months). >40% of patients in both groups required dose adjustments to 37.5–25 mg daily.
Our study confirms that current therapy of advanced GIST with tyrosine kinase inhibitors (both in 1st and 2nd line) in older patients enable to achieve the similar disease control rate and final outcomes as in younger patients, but it demands close cooperation of experienced oncologist with patients for dose modifications and side effects management. Limitation of our study is that the patients did not undergo a comprehensive geriatric assessment, what might be helpful for personalized management of patients. Nevertheless, we confirm that older patients with GIST should not receive less treatment irrespective of comorbidities.
Current guidelines recommend use of adjuvant imatinib therapy for many patients with gastrointestinal stromal tumours (GISTs); however, its optimal treatment duration is unknown and some patient ...groups do not benefit from the therapy. We aimed to apply state-of-the-art, interpretable artificial intelligence (ie, predictions or prescription logic that can be easily understood) methods on real-world data to establish which groups of patients with GISTs should receive adjuvant imatinib, its optimal treatment duration, and the benefits conferred by this therapy.
In this observational cohort study, we considered for inclusion all patients who underwent resection of primary, non-metastatic GISTs at the Memorial Sloan Kettering Cancer Center (MSKCC; New York, NY, USA) between Oct 1, 1982, and Dec 31, 2017, and who were classified as intermediate or high risk according to the Armed Forces Institute of Pathology Miettinen criteria and had complete follow-up data with no missing entries. A counterfactual random forest model, which used predictors of recurrence (mitotic count, tumour size, and tumour site) and imatinib duration to infer the probability of recurrence at 7 years for a given patient under each duration of imatinib treatment, was trained in the MSKCC cohort. Optimal policy trees (OPTs), a state-of-the-art interpretable AI-based method, were used to read the counterfactual random forest model by training a decision tree with the counterfactual predictions. The OPT recommendations were externally validated in two cohorts of patients from Poland (the Polish Clinical GIST Registry), who underwent GIST resection between Dec 1, 1981, and Dec 31, 2011, and from Spain (the Spanish Group for Research in Sarcomas), who underwent resection between Oct 1, 1987, and Jan 30, 2011.
Among 1007 patients who underwent GIST surgery in MSKCC, 117 were included in the internal cohort; for the external cohorts, the Polish cohort comprised 363 patients and the Spanish cohort comprised 239 patients. The OPT did not recommend imatinib for patients with GISTs of gastric origin measuring less than 15·9 cm with a mitotic count of less than 11·5 mitoses per 5 mm2 or for those with small GISTs (<5·4 cm) of any site with a count of less than 11·5 mitoses per 5 mm2. In this cohort, the OPT cutoffs had a sensitivity of 92·7% (95% CI 82·4–98·0) and a specificity of 33·9% (22·3–47·0). The application of these cutoffs in the two external cohorts would have spared 38 (29%) of 131 patients in the Spanish cohort and 44 (35%) of 126 patients in the Polish cohort from unnecessary treatment with imatinib. Meanwhile, the risk of undertreating patients in these cohorts was minimal (sensitivity 95·4% 95% CI 89·5–98·5 in the Spanish cohort and 92·4% 88·3–95·4 in the Polish cohort). The OPT tested 33 different durations of imatinib treatment (<5 years) and found that 5 years of treatment conferred the most benefit.
If the identified patient subgroups were applied in clinical practice, as many as a third of the current cohort of candidates who do not benefit from adjuvant imatinib would be encouraged to not receive imatinib, subsequently avoiding unnecessary toxicity on patients and financial strain on health-care systems. Our finding that 5 years is the optimal duration of imatinib treatment could be the best source of evidence to inform clinical practice until 2028, when a randomised controlled trial with the same aims is expected to report its findings.
National Cancer Institute.
Rectal gastrointestinal stromal tumours (GISTs) are rare tumours. Variability in the management may influence outcome, but there is a lack of understanding regarding contemporary variance in care. A ...multicenter, international, retrospective cohort study was performed to elucidate characteristics and outcomes of rectal GIST in European practice, with particular reference to surgical approach.
All rectal GIST patients diagnosed between 2009 and 2018 were identified from five European databases. Recurrence free survival (RFS) and overall survival (OS) were estimated using Kaplan-Meier method. Possible confounders were identified using Cox regression analyses.
From 210 patients, 155 patients had surgery. The three main types of surgery were local tumour resection (LTR, n = 46), low anterior resection (LAR, n = 31) and abdomino-perineal resection (APR, n = 32). Most patients received neoadjuvant (65%) and/or adjuvant imatinib therapy (66%). Local recurrence rate after surgery was 15% and overall recurrence rate 28%. No significant differences were found in terms of RFS nor OS between LTR, LAR and APR. However, locally resected tumours were smaller, while LAR and APR patients more often received perioperative imatinib. General hospitals treated smaller GISTs, offered imatinib less frequently, and had a higher tumour rupture rate. In the multivariate analysis in the group having LTR, APR or LAR, the only significant prognostic factor for local recurrence was higher age (HR 1.06, CI 1.00–1.12, p = 0.048).
In European clinical practice for rectal GIST, LTR, LAR and APR have comparable local control. Multimodal approach is higher and tumour rupture less frequent in specialist centres compared to general hospitals.
•Rectal GIST is a rare entity of soft tissue sarcoma•Most rectal GISTs are resected surgically and treated with perioperative imatinib•Despite multimodal treatment, the recurrence rate is high•Aspects of care are of higher quality in specialist centres•Referral of rectal GIST to specialist centres is therefore recommended
The neutrophil-to lymphocyte ratio (NLR) has been proven to be correlated with outcomes in various cancer types, including gastrointestinal stromal tumors (GIST). There is limited data regarding the ...clinical value of NLR during second line therapy after failure of imatinib and there is an urgent need for more precise predictive factors for therapy. The aim of this study was to assess the association of the pretreatment NLR with progression free survival (PFS) and overall survival (OS) in patients with unresectable/metastatic GIST treated with sunitinib in a second line of treatment. In this analysis 146 out of 230 patients with unresectable/metastatic GIST were included, who were treated between 2005 and 2016 with sunitinib after failure of imatinib, with complete clinical data. In all patients, the NLR was assessed at baseline. The NLR cutoff of 2.4 was selected. The Kaplan-Meier method with the long-rank test and Cox proportional hazards model were applied for statistical analysis. Median PFS was 12.4 months with a 2-year rate of 27.1% and a 5-year rate of 4.8%. Median OS was 22.8 months, whereas 2- and 5-year rates were 47.8 and 13.8%, respectively. Patients with NLR>2.4 had significantly shorter OS: Median OS was 30 months for NLR≤2.4 vs. 16.4 months for NLR>2.4 (P=0.002); median PFS was 18.2 vs. 9.6 (P=0.075), respectively. In a multivariate model adjusted for mitotic index, primary location of tumor and driver mutation in
exon 11, NLR was proven to be independently associated with OS (HR 1.92, 95% CI 1.27-2.9, P=0.002) but not PFS (HR 1.31, 95%CI 0.89-1.93, P=0.17). The present data demonstrate that NLR can serve as an independent prognostic factor for patients with advanced GIST treated with sunitinib.
Abstract only
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Background: The real-world data on outcomes of adjuvant therapy in high-risk gastrointestinal stromal tumors (GIST) are very limited. Methods: We have analyzed the data of 107 ...consecutive patients (52 male, 56 female) with GIST after resection treated with adjuvant imatinib (for planned 3 years with initial dose 400 mg daily, started not later than 4 months after operation) in 6 oncological centers in 2013-2018. All patients were required to have high risk of recurrence (at least 50% according to NCCN/AFIP criteria), known mutational status to exclude PDGFRA D842V mutants and KIT/PDGFRA-wild type cases from therapy. Median follow-up time was 24 months. Results: The most common primary localization of GIST was small bowel (63 patients; 59%), followed by the stomach (40 patients; 37%). The majority of GIST cases harbored exon 11 KIT mutations (88 cases, 82%), 11 cases had exon 9 KIT mutations (10%), 8 had other KIT/PDGFRA mutations potentially sensitive to imatinib. Thirty three patients (31%) finished 3-year adjuvant imatinib therapy as planned, 59 (55%) still continue therapy, 4 (4%) patients had finished adjuvant therapy prematurely due to toxicity, 6 (6%) due to disease progression on treatment and 5 (4%) due to other reasons. The disease relapse was detected in 16 patients, of them in 4 cases in exon 9 KIT mutants (36%), and 10 cases in patients with exon 11 KIT mutations (11%) p < 0.05. Estimated 4-year relapse-free survival (RFS) rate is 78%. Conclusions: The early results of adjuvant therapy with imatinib in routine practice outside clinical trials in high-risk mutation-drive GIST patients only confirm high efficacy of this therapy with better tolerability than in clinical trials. Moreover, overrepresentation of exon 9 KIT mutants in a group of patients with disease relapse may indicate that standard 400 mg dose in adjuvant treatment is not sufficient for prevention of disease relapse.
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