Colorectal cancer remains a leading cause of cancer-related morbidity and mortality worldwide, and accurate staging is critical for guiding treatment decisions. Lymph node involvement serves as one of the most decisive prognostic indicators, distinguishing stage II from stage III disease and influencing the use of adjuvant chemotherapy. Within this framework, the classification of metastatic deposits in lymph nodes has been refined into macrometastases, micrometastases, and isolated tumour cells (ITCs). While macrometastases and micrometastases have well-established clinical implications, the biological and prognostic relevance of ITCs remains an area of uncertainty. Conventional histopathological examination and immunohistochemistry have been unable to consistently demonstrate that ITCs influence survival or recurrence in colorectal cancer. However, molecular profiling technologies, including genomic sequencing, transcriptomic analysis, epigenetic studies, and single-cell approaches, offer a new opportunity to evaluate whether ITCs are biologically inert or represent seeds of metastatic potential. This paper provides a comprehensive literature-based review of ITCs in colorectal cancer, with particular emphasis on the application of molecular profiling techniques to clarify their prognostic and predictive significance. The discussion extends to emerging technologies such as artificial intelligence, digital pathology, and liquid biopsy, which may integrate with ITC profiling in the future. Finally, challenges, limitations, and future research directions are outlined. Molecularly characterizing ITCs may transform their current ambiguous clinical status into a defined biomarker guiding staging, treatment, and surveillance in colorectal cancer.