The rising incidence and mortality of early-onset colorectal cancer (EOCRC), defined as disease occurring in patients younger than 50, has emerged as a clinically significant trend with implications for screening, diagnosis, and survivorship. While overall colorectal cancer mortality has declined, EOCRC-related deaths are increasing disproportionately in younger populations, many of whom present with locally advanced disease.

A recent case at Baptist Health Miami Cancer Institute illustrates both the challenges and opportunities in managing this population.

Case Presentation

A 37-year-old female with no significant prior colorectal history presented with rectal bleeding, progressive change in stool caliber, tenesmus, and unintentional weight loss. These symptoms were initially attributed to concurrent in-vitro fertilization (IVF) treatment, contributing to a delay in diagnostic evaluation.

Colonoscopy confirmed rectal adenocarcinoma. Staging workup demonstrated stage III disease (node-positive, M0), consistent with locally advanced rectal cancer (LARC).

This presentation is consistent with broader EOCRC trends, in which younger patients frequently present with more advanced disease, in part due to delayed recognition of symptoms and lower clinical suspicion.

Treatment Approach

The patient underwent standard multimodality therapy consisting of:

• Systemic chemotherapy
• Neoadjuvant radiation therapy with concurrent chemotherapy
• Surgical resection via total mesorectal excision (TME)

This sequencing aligns with contemporary management of LARC, where neoadjuvant therapy is utilized to:

• Downstage the tumor
• Improve resectability
• Reduce local recurrence risk
• Increase the likelihood of sphincter preservation

While total neoadjuvant therapy (TNT) is increasingly adopted in many centers, the overarching principle remains early integration of systemic and local therapies.

Role of Proton Therapy

Given the patient’s age and desire for future fertility, radiation modality selection was a critical component of treatment planning, says Michael Chuong, M.D., medical director of Miami Cancer Institute’s department of radiation oncology.

Proton therapy was selected over conventional photon-based radiotherapy due to its dosimetric advantages, particularly in the treatment of pelvic malignancies. Unlike photon therapy, proton beams exhibit a Bragg peak, allowing for maximal dose deposition within the target while minimizing exit dose.

In this case, proton therapy enabled:

• Reduced integral dose to uninvolved bowel, bladder, and reproductive organs
• Significant sparing of ovarian tissue
• Decreased exposure to bone marrow and surrounding pelvic structures

These factors are particularly relevant in younger patients, where long-term risks—including infertility, premature ovarian insufficiency, bowel dysfunction, and secondary malignancies—must be carefully considered.

As Dr. Chuong notes, minimizing radiation exposure to non-target pelvic tissues is essential in patients expected to achieve long-term survival.

Tolerance and Outcomes

The patient completed 28 fractions of proton radiation with concurrent chemotherapy. Treatment was well tolerated, with minimal acute toxicity limited primarily to fatigue. Notably, she avoided many of the gastrointestinal and genitourinary side effects commonly associated with pelvic radiation.

She subsequently underwent surgical resection, with pathology demonstrating clear margins and no residual nodal disease in 17 examined lymph nodes.

At follow-up, she remains in remission with no significant long-term treatment-related morbidity.

Fertility and Survivorship Considerations

EOCRC presents unique survivorship challenges. Unlike older patients, many are in their reproductive years and face potential treatment-related infertility.

In this case, fertility preservation was a central consideration. By reducing radiation dose to the ovaries and surrounding reproductive structures, proton therapy may lower the risk of:

• Premature menopause
• Infertility
• Long-term endocrine dysfunction

The patient is currently pursuing family-building options via surrogacy, underscoring the importance of integrating oncofertility counseling into treatment planning for younger patients.

Implications for Clinical Practice

This case highlights several key considerations for physicians:

1. Rising burden of EOCRC
   Clinicians should maintain a high index of suspicion for colorectal cancer in younger patients presenting with rectal bleeding, altered bowel habits or tenesmus. Delays in diagnosis remain a major contributor to advanced-stage presentation.

2. Importance of timely screening and evaluation
   While screening guidelines now recommend initiation at age 45 for average-risk individuals, symptomatic patients require prompt diagnostic workup regardless of age.

3. Value of multidisciplinary care
   Optimal outcomes in rectal cancer depend on coordinated management across medical oncology, radiation oncology, colorectal surgery, and supportive care services.

4. Treatment personalization in younger patients
   In EOCRC, treatment decisions should extend beyond oncologic control to include long-term toxicity, quality of life, and fertility preservation.

5. Emerging role of advanced radiation modalities
   Proton therapy represents a potentially valuable tool in select patients, particularly younger individuals with curable disease where reduction in late toxicity is a priority.

Conclusion

As EOCRC incidence continues to rise, clinicians are increasingly confronted with balancing aggressive oncologic management with long-term survivorship considerations.

This case demonstrates that, even in stage III rectal cancer, carefully selected multimodality therapy—including advanced radiation techniques—can achieve excellent oncologic outcomes while preserving quality of life and future reproductive potential.

For younger patients, the goal is no longer solely cure, but cure with minimal long-term compromise—a standard that will continue to shape treatment strategies in rectal cancer care.