With the advent of the IoT, AI, ML, and DL algorithms, the landscape of
data-driven medical applications has emerged as a promising avenue for
designing robust and scalable diagnostic and prognostic models from medical
data. This has gained a lot of attention from both academia and industry,
leading to significant improvements in healthcare quality. However, the
adoption of AI-driven medical applications still faces tough challenges,
including meeting security, privacy, and quality of service (QoS) standards.
Recent developments in \ac{FL} have made it possible to train complex
machine-learned models in a distributed manner and have become an active
research domain, particularly processing the medical data at the edge of the
network in a decentralized way to preserve privacy and address security
concerns. To this end, in this paper, we explore the present and future of FL
technology in medical applications where data sharing is a significant
challenge. We delve into the current research trends and their outcomes,
unravelling the complexities of designing reliable and scalable \ac{FL} models.
Our paper outlines the fundamental statistical issues in FL, tackles
device-related problems, addresses security challenges, and navigates the
complexity of privacy concerns, all while highlighting its transformative
potential in the medical field. Our study primarily focuses on medical
applications of \ac{FL}, particularly in the context of global cancer
diagnosis. We highlight the potential of FL to enable computer-aided diagnosis
tools that address this challenge with greater effectiveness than traditional
data-driven methods. We hope that this comprehensive review will serve as a
checkpoint for the field, summarizing the current state-of-the-art and
identifying open problems and future research directions.Comment: Accepted at IEEE Internet of Things Journa