Objective:

To highlight the management of early-onset locally advanced rectal cancer (LARC) with a focus on fertility preservation and the critical role of proton therapy in improving treatment outcomes.

Key Findings:

• Early-onset colorectal cancer (EOCRC) is increasingly common, with younger patients often presenting with advanced disease, necessitating timely diagnosis.
• Proton therapy offers significant advantages in reducing radiation exposure to reproductive organs and surrounding tissues, which is critical for long-term health.
• Multidisciplinary care is essential for optimal outcomes in rectal cancer management, ensuring comprehensive treatment strategies.

Interpretation:

The case underscores the need for timely diagnosis and personalized treatment strategies that consider long-term quality of life and fertility in younger patients, emphasizing the importance of integrating oncofertility counseling.

Limitations:

• The case study is based on a single patient experience, limiting generalizability.
• Further research is needed to establish long-term outcomes of proton therapy in this population, particularly regarding fertility preservation.

Conclusion:

Multimodality therapy, including advanced radiation techniques like proton therapy, can achieve excellent oncologic outcomes while preserving quality of life and reproductive potential in younger patients with LARC.