PATIENTS AND METHODS: A retrospective study was conducted based on incident lung cancer cases diagnosed between 2017 and 2019 in Lampang (Thailand), Penang (Malaysia), Singapore and Yogyakarta (Indonesia). Cases (n = 3413) were defined using the International Classification of Diseases for Oncology third edition. In Singapore, a clinical series obtained from the National Cancer Centre was used to identify patients, while corresponding population-based cancer registries were used elsewhere. Tumor and clinical information were abstracted by chart review according to a predefined study protocol. Molecular testing of epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK) gene rearrangement, ROS1 gene rearrangement and BRAF V600 mutation was recorded.
RESULTS: Among 2962 cases with a specified pathological diagnosis (86.8%), most patients had non-squamous NSCLC (75.8%). For cases with staging information (92.1%), the majority presented with metastatic disease (71.3%). Overall, molecular testing rates in the 1528 patients with stage IV non-squamous NSCLC were 67.0% for EGFR, 42.3% for ALK, 39.1% for ROS1, 7.8% for BRAF and 36.1% for PD-L1. Among these patients, first-line systemic treatment included chemotherapy (25.9%), targeted therapy (35.6%) and immunotherapy (5.9%), with 31% of patients having no record of antitumor treatment. Molecular testing and the proportion of patients receiving treatment were highly heterogenous between the regions.
CONCLUSIONS: This first analysis of data from a clinically annotated registry for lung cancer from four settings in Southeast Asia has demonstrated the feasibility of integrating clinical data within population-based cancer registries. Our study results identify areas where further development could improve patient access to optimal treatment.
SUMMARY: Background Mutation of the growth factor-independent 1B (GFI1B) fifth DNA-binding zinc-finger domain causes macrothrombocytopenia and α-granule deficiency leading to clinical bleeding. The phenotypes associated with GFI1B variants disrupting non-DNA-binding zinc-fingers remain uncharacterized. Objectives To determine the functional and phenotypic consequences of GFI1B variants disrupting non-DNA-binding zinc-finger domains. Methods The GFI1B C168F variant and a novel GFI1B c.2520 + 1_2520 + 8delGTGGGCAC splice variant were identified in four unrelated families. Phenotypic features, DNA-binding properties and transcriptional effects were determined and compared with those in individuals with a GFI1B H294 fs mutation of the fifth DNA-binding zinc-finger. Patient-specific induced pluripotent stem cell (iPSC)-derived megakaryocytes were generated to facilitate disease modeling. Results The DNA-binding GFI1B variant C168F, which is predicted to disrupt the first non-DNA-binding zinc-finger domain, is associated with macrothrombocytopenia without α-granule deficiency or bleeding symptoms. A GFI1B splice variant, c.2520 + 1_2520 + 8delGTGGGCAC, which generates a short GFI1B isoform that lacks non-DNA-binding zinc-fingers 1 and 2, is associated with increased platelet CD34 expression only, without quantitative or morphologic platelet abnormalities. GFI1B represses the CD34 promoter, and this repression is attenuated by different GFI1B zinc-finger mutations, suggesting that deregulation of CD34 expression occurs at a direct transcriptional level. Patient-specific iPSC-derived megakaryocytes phenocopy these observations. Conclusions Disruption of GFI1B non-DNA-binding zinc-finger 1 is associated with mild to moderate thrombocytopenia without α-granule deficiency or bleeding symptomatology, indicating that the site of GFI1B mutation has important phenotypic implications. Platelet CD34 expression appears to be a common feature of perturbed GFI1B function, and may have diagnostic utility.