It is an unquestionable fact that cancer, also called
malignancy, has or will soon become the major global health care problem
with an increasing incidence worldwide. Conventional treatment approaches
(e.g., radiation or chemotherapy) treat both cancerous and surrounding
normal tissues simultaneously, which leads to a poor therapeutic effect
on tumors and severe toxic side effects on healthy tissues. Considering
these thematic issues, the design and development of more efficient
treatment approaches is one of the most important demands of health
care in the near future. In this context, the emergence of nanotechnology
opens new opportunities for addressing the issues of conventional
drug delivery systems (DDSs) for cancer therapy. Theranostic nanomedicines
are indebted to the advent of nanotechnology and were introduced by
Funkhouser in 2002. These nanomedicines are the newest DDSs that combine
diagnostic and therapeutic properties into a single platform. Theranostic
nanomedicines are generally composed of targeting agents, diagnostic
tracers, effective drug(s), and biomaterial(s) as the matrix to the
formulation. Among these, biomaterials have a pivotal role in theranostic
nanomedicines due to their direct influence on the system effectiveness.
In this context, natural polymers can be considered as potential candidates,
mainly due to their inherent physicochemical as well as biological
advantages. However, natural polymers have some drawbacks, which can
be addressed through the chemical modification approach. In this review,
we will highlight the recent progress in the development of theranostic
nanomedicines based on chemically modified natural polymers as well
as research prospects for the future.