Elevated Cancer Risks for Colorectal Cancer Survivors Highlighted in Study

A recent study conducted by researchers at Flinders University in South Australia has revealed that survivors of colorectal cancer (CRC) face a significantly heightened risk of developing multiple primary cancers (MPCs), including prostate, lung, breast, and blood cancers. This research, published in Cancer Medicine, underscores a growing clinical challenge as advancements in treatment have led to increased survival rates among CRC patients, particularly as the population ages.

The study, led by PhD candidate Mulugeta Melku from the Flinders Health and Medical Research Institute (FHMRI), analyzed data from the South Australian Cancer Registry encompassing 26,729 CRC survivors diagnosed between 1982 and 2017. According to Melku, "While patient outcomes have improved over time, CRC survivors already face an increased risk of developing one or more cancers in another part of the colon or other primary sites. This study shows that CRC survivors are at increased risk of subsequent cancers compared to the general population, highlighting the need for targeted surveillance, particularly for early detection and treatment of prostate, lung, breast, and blood cancers."

Senior researcher Associate Professor Erin Symonds, also from the Southern Adelaide Local Health Network, emphasized the importance of estimating the incidence, trends, and risks associated with other types of MPCs following a CRC diagnosis. Symonds stated, "Estimating the incidence, trend and risk of other kinds of MPCs after a diagnosis of CRC will help service delivery, testing and treatment in the coming years, as the population continues to age and survivors live longer."

The findings indicate that the most prevalent MPCs among CRC survivors over time include prostate cancer, subsequent CRC, lung cancer, hematological malignancies, breast cancer, urinary tract cancers, and skin melanoma. Colorectal cancer remains a significant public health issue, ranking as the fourth most diagnosed cancer in Australia and the second leading cause of cancer-related deaths. Despite substantial advancements in screening, diagnostic tools, and treatment options over the past four decades, the incidence of cancer diagnoses in Australia has surged, rising from approximately 88,000 cases in 2000 to around 169,000 in 2022. This increase, exceeding 90%, is primarily attributed to a growing population and an increasing number of individuals reaching older ages, where cancer prevalence is higher. Researchers project that cancer diagnoses could rise to around 209,000 by 2034.

The Flinders University research team has also published a supplementary paper examining risk factors for developing additional cancers following a colorectal cancer diagnosis. This paper, titled "Risk Factors of Multiple Primary Cancers Among Colorectal Cancer Survivors" (2025), was co-authored by Melku along with Oliver G. Best, Jean M. Winter, Lauren A. Thurgood, Muktar Ahmed, Ganessan Kichenadasse, and Erin L. Symonds. It highlights the relevance of understanding these risk factors to enhance surveillance programs for early detection of subsequent cancers.

Further research is essential for improving treatment outcomes and overall survival rates for colorectal cancer survivors. Associate Professor Symonds noted, "Studies such as this increase understanding of MPCs risks which, in turn, helps to develop suitable strategies to enhance and refine surveillance programs for early detection of subsequent cancers."

This study is particularly timely given the aging population and the increasing survival rates for cancer patients, necessitating a reevaluation of cancer care strategies to address the unique challenges faced by survivors. The implications of this research extend beyond individual health, impacting healthcare policies and resource allocation in the domain of cancer management and prevention.

In summary, as colorectal cancer survivors live longer, the need for targeted cancer surveillance and comprehensive healthcare strategies becomes increasingly critical. The findings from Flinders University serve as a clarion call for the medical community to prioritize the monitoring and treatment of subsequent cancers in this vulnerable patient population.