Early response evaluation using F-18-FDG-PET/CT does not influence management of patients with metastatic gastrointestinal stromal tumors (GIST) treated with palliative intent

Aim The aim of this study was to investigate the impact of F-18-FDG-PET/CT on treatment decision making in metastatic gastrointestinal stromal tumor (GIST) patients.Methods This study retrospectively evaluated F-18-FDG-PET/CT scans to monitor response of metastatic GIST patients treated with palliative intent. Data from the Dutch GIST Registry was used. Early scans ( 10 weeks after start of treatment) were scored on the impact in change of treatment.Results Sixty-one PET/CTscans were performed for treatment evaluation in 39 patients with metastatic GIST of which 36 were early scans and 25 were late scans. Early PET/CT scans led to a change in management in 5.6 % of patients and late PET/CT scans led to a change in management in 56 % of patients. Change in management was more often seen after scans with lack of metabolic response (48 % vs. 11 % in scans with metabolic response, p = 0.002). Neither metabolic response nor change in treatment were more often seen in patients with KIT mutations compared to patients with non-KIT mutations (metabolic response 65 % KIT vs. 46 % non-KIT, p = 0.33, and change in management 28 % KIT vs. 21 % nonKIT, p = 0.74).Conclusion(18)F-FDG-PET/CT is not recommended for early response evaluation in an unselected patient population with metastatic GIST, since it does not influence treatment decisions. F-18-FDG- PET/ CT, however, can be useful for late response assessment, especially in case of indeterminate CT results.Imaging- and therapeutic targets in neoplastic and musculoskeletal inflammatory diseas

Treatment of patients with MYC rearrangement positive large B-cell lymphoma with R-CHOP plus lenalidomide: results of a multicenter HOVON phase II trial.

Patients with MYC-rearrangement positive large B-cell lymphoma (MYC+ LBCL) have an inferior prognosis following standard first-line therapy with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP) as compared to patients without MYC rearrangement. Although intensive chemotherapy regimens yield higher remission rates, toxicity remains a concern. Lenalidomide is an oral immunomodulatory drug which downregulates MYC and its target genes thereby providing support using lenalidomide as additional therapeutic option for MYC+ LBCL. A phase II trial was conducted evaluating the efficacy of lenalidomide (15 mg day 1-14) in combination with R-CHOP (R2CHOP) in newly diagnosed MYC+ LBCL patients identified through a nationwide MYC-FISH screening program. The primary endpoint was complete metabolic response (CMR) on centrally reviewed 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)-computer tomography (CT)-scan at end-of-treatment. Secondary endpoints were overall survival (OS), disease-free survival (DFS) and event-free survival (EFS). Eighty-two patients with stage II-IV MYC+ LBCL were treated with 6 cycles of R2CHOP. At EOT, 67% (confidence interval (CI) 58-75%) of the patients reached CMR. With a median follow-up of 25.4 months, 2-year estimates (95% CI) for OS, DFS, EFS were 73% (62-82%), 75% (63-84%) and 63% (52-73%) respectively. In this prospective trial for newly diagnosed MYC+ LBCL patients, we found that administering R2CHOP was safe, and yields comparable CMR and survival rates as in studies applying more intensive chemotherapy regimens. Hence, these findings offer new prospects for MYC+ LBCL patients and warrant comparison in prospective randomized clinical trials. This trial was registered at www.clinicaltrialsregister.eu (#2014-002654-39).status: Published onlin