Quantum dots (QDs) are optically distinct nanoscale semiconductors and fluorescent compounds that are restricted to 100–1000 atoms in three spatial dimensions, with sizes ranging from 1.5–10 nm. Cadmium telluride quantum dots (CdTe QDs), which are made of cadmium telluride atoms, have broad absorption, limited emission, and photostability due to their spectral properties. The potential applications of CdTe QDs in gamma ray detectors, sensors, solar power cells, optical electronics, biolabelling, and biological imaging are highly intriguing. QDs may be used in a variety of ways to treat cancer. They can be used for intraoperative navigation, controlled release, and as drug carriers for precise drug administration when combined with other biomolecules. Research suggests that QDs could be helpful in cancer immunotherapy, which could lead to more innovative methods for treating cancer. Although QDs provide intriguing prospects for cancer prevention, diagnosis, and treatment, their clinical application necessitates a focused effort toward biosafety, biocompatibility, and translational research.