A randomized study of 6 vs 3 years of adjuvant imatinib in patients with localized GIST at high risk of relapse.

BACKGROUND: The administration of adjuvant imatinib during three years is indicated after resection of primary localized GIST at high risk of recurrence, but many patients relapse afterwards. METHODS: IMADGIST (NCT02260505) was a multicenter open-label, randomized phase III study evaluating the maintenance of imatinib for 3 more years (6-years arm) compared to Interruption (3-years arm) from the day of randomization, conducted in the French Sarcoma Group. The primary endpoint was intent-to treat disease-free survival (DFS). Secondary endpoints include overall survival, time to imatinib resistance, response after imatinib reintroduction at relapse, safety. RESULTS: From December 24th 2014 to April 4th 2023; 136 patients aged ≥18, ECOG PS ≤2, with a localized GIST with a R0 or R1 surgery, and a risk of tumor recurrence ≥35% according to NCCN risk classification were randomized in 14 centers. Sixty-five patients were randomized to the 3-Years arm vs. 71 in the 6-Years arm. There were 68 males and females. Primary sites were gastric and small bowel in 60 (44%) and 64 (47%) patients respectively. Respectively 52 (38%) and 71 (52%) of patients had a risk of relapse of 35-70% and >70%.. With a median follow-up of 55 (IQR=46-59) months post randomization, DFS was significantly superior in the 6-Years arm (HR: 0.40 [0.20-0.69], p=0.0008). Time to imatinib resistance, survival, adverse events and quality of life are not different in the 2 arms. CONCLUSIONS: Three additional years of adjuvant imatinib reduces the risk of relapse in patients who have received 3 years of adjuvant imatinib with an acceptable tolerance.

Drug-drug interactions with proton pump inhibitors in cancer patients: an underrecognized cause of treatment failure.

New concepts and drugs have revolutionized medical treatment for cancers. These drugs, which are very expensive and usually well tolerated, have dramatically improved cancer prognosis. We must use them wisely for patients to fully benefit. Gastric acid antisecretory drugs and particularly proton pump inhibitors (PPIs) revolutionized the treatment of gastroduodenal ulcers and severe gastroesophageal reflux, but are frequently overused for symptomatic treatment of epigastric pain or heartburn. Long-term acid suppression may alter the efficacy of many anticancer drugs, such as tyrosine kinase inhibitors (TKIs), cyclin-dependent kinase (CDK) 4/6 inhibitors and immune checkpoint inhibitors (ICIs), by either decreasing gastric acid secretion and thus drug absorption, or by modifying the gut microbiome that modulates the response to ICIs. Oncologists thus need to pay particular attention to the concomitant use of PPIs and anticancer drugs. These interactions translate into major clinical impacts, with demonstrated loss of efficacy for some TKIs (erlotinib, gefitinib, pazopanib), and conflicting results with many other oral drugs, including capecitabine and CDK 4/6 inhibitors. Furthermore, the profound changes in the gut microbiome due to using PPIs have shown that the benefit of using ICIs may be suppressed in patients treated with PPIs. As the use of PPIs is not essential, we must apply the precautionary principle. The first sentence of a recent Comment in Nature was "Every day, millions of people are taking medications that will not help them". We fear that every day millions of cancer patients are taking medications that harm them. While this may well be only association and not causation, there is enough to make us pause until we reach a clear answer. All these data should encourage medical oncologists to refrain from prescribing PPIs, explaining to patients the risks of interaction in order to prevent inappropriate prescription by another physician.

Patterns of care and outcomes of 417 patients with METAstatic SYNovial sarcoma (METASYN): real-life data from the French Sarcoma Group (FSG).

BACKGROUND: Synovial sarcoma (SS) occurs in both adult and pediatric patients. The primary aim of this study is to describe the outcomes, prognostic factors, and treatment of patients with metastatic SS within a nationwide cohort. PATIENTS AND METHODS: All pediatric and adult patients with metastatic SS are registered in the French Sarcoma Group database. Data were collected from the national database https://conticabase.sarcomabcb.org/ up to March 2020. Descriptive and comparative analyses were conducted using SAS 9.4 and Stata Special Edition 16.1 software. RESULTS: Between January 1981 and December 2019, 417 patients with metastatic SS from 17 French sarcoma centers were included, including 64 (15.3%) under the age of 26 years. Median age was 42.5 years (range 9-87 years). The metastases were synchronous (cohort 1) or metachronous (cohort 2) in 18.9% (N = 79) and 81.1% (N = 338) patients, respectively. Median overall survival (OS) from the date of metastasis was 22.3 months (95% confidence interval 19.7-24.1 months). First-line chemotherapy without ifosfamide and/or doxorubicin was unfavorable for progression-free survival and OS (P < 0.001). Concerning cohort 1, young age, surgery of the primary tumor, and single metastatic site were independent favorable prognostic factors for OS. In cohort 2, surgery within an expert French Sarcoma Group center, absence of chemotherapy in the perioperative setting, the lungs as a single metastatic site, time to first metastasis >12 months, local therapy, and ifosfamide in the first metastatic line were independent favorable prognostic factors. CONCLUSIONS: The outcome of patients with metastatic SS is influenced by local treatment, management in reference centers, and cytotoxic treatments given in the perioperative and metastatic setting.

Impact of the timing of tumor assessments on median progression-free survival in clinical trials in advanced cancer patients.

BACKGROUND: Survival-based surrogate endpoints such as progression-free survival (PFS) are commonly used in oncology clinical trials. The evaluation-time bias in the assessment of median disease progression in randomized trials has been suggested by several simulation studies, but never demonstrated in the clinic. We aimed to demonstrate the existence of potential evaluation-time bias by assessing the impact of the timing of tumor assessments on median PFS from control arms without any active treatment of randomized controlled trials involving advanced cancer patients. MATERIALS AND METHODS: A systematic literature search of English language publications from 1 January 2000 to 7 January 2021 was performed using MEDLINE (PubMed). Eligible trials for our meta-analysis included all randomized clinical trials evaluating anticancer drugs in adult patients with advanced cancers with a control arm without any anticancer drug consisting of best supportive care with or without a placebo. We performed a meta-regression analysis to analyze the correlation between the timing of the first tumor assessment and median PFS in patients randomized in the control arms without any active treatment. RESULTS: Of 3551 studies screened, 97 eligible trials were retrieved involving 36  747 patients, including 14  229 patients randomized into the control arms. A later first tumor assessment correlated with a prolonged median PFS (R2 = 0.44, P < 10-5). CONCLUSIONS: Our results confirm the existence of potential evaluation-time bias in clinical research that had been suggested by simulation studies. The timing of tumor assessments should be kept the same in precision medicine trials using the PFS ratio as an efficacy endpoint.