A diagnostic randomized controlled trial to validate novel dried blood spot (DBS) based technology for prognosis and screening of leukemia transcripts: study protocol.

[BACKGROUND] Leukemia is the most common subtype of cancer in Indian children and ranks among the top ten cancers in the adult population according to ICMR cancer registry 2022 (National Cancer Registry Programme, Cancer incidence and mortality in India 2022, 2022). Current leukemia diagnostics rely on sophisticated molecular tests that are not available at all healthcare centers, particularly in remote and tier-two cities. Access to specialized molecular diagnostics and prognostic tests is limited to fewer than 20 centers across India, serving a population of approximately 1.3 billion people (National Cancer Registry Programme, Cancer incidence and mortality in India 2022, 2022). This restricted accessibility results in delayed diagnosis, suboptimal risk stratification, increased economic burden, and higher mortality rates compared to high-income countries.

[METHODS] This is a multicenter, randomized, double-blind diagnostic interventional trial designed to validate a novel dried blood spot (DBS) based technology for leukemia transcript determination. The study will be conducted across five sites in India. Newly diagnosed acute leukemia patients (n = 300; 200 ALL and 100 AML) will be randomized into two arms: interventional arm (DBS-based testing) and comparator arm (conventional testing). The primary outcome is the sensitivity, specificity, and positive predictive value of the DBS-based method compared to conventional diagnostic methods. Secondary outcomes include overall survival, event-free survival, and relapse rates over one year of follow-up.

[DISCUSSION] This study addresses a critical gap in leukemia diagnostic accessibility in low- and middle-income countries. The novel DBS-based technology has the potential to withstand tropical temperature and humidity conditions for 24-48 h, making it suitable for transport from remote areas. Preliminary work has shown 100% specificity and 99% sensitivity compared to standard reference methods (PLoS One 13(1):e0191421, 2019). If validated, this technology could significantly improve leukemia outcomes through earlier diagnosis, better risk stratification, and reduced abandonment rates.

[TRIAL REGISTRATION] Clinical Trials Registry-India (CTRI): CTRI/2024/06/069601.