Why is radiotherapy and chemotherapy not used for early-stage rectal cancer?

The reasons for not using chemotherapy or radiotherapy in early-stage rectal cancer may include mild disease, favorable tumor location allowing complete surgical resection, good tumor biological behavior, significant side effects of chemoradiotherapy, advanced patient age, or presence of severe comorbidities. A detailed analysis is as follows:

1. Mild disease: In early-stage rectal cancer, the tumor is confined to the mucosa or submucosal layer without lymph node or distant metastasis, so chemotherapy or radiotherapy is generally unnecessary.

2. Favorable tumor location enabling complete surgical resection: Tumors located in the middle or upper rectum that are easily resected surgically and lack high-risk features may be treated with surgery alone.

3. Favorable tumor biological characteristics: Rectal cancers with high differentiation and slow growth tend to have lower invasiveness and metastatic potential, resulting in a lower risk of recurrence after surgical removal.

4. Significant side effects of chemotherapy and radiotherapy: While chemoradiotherapy kills cancer cells, it also damages normal cells, leading to various side effects such as hair loss and leukopenia. Given that early-stage tumors have not widely spread, the necessity of chemoradiotherapy is relatively low; therefore, avoiding unnecessary treatment-related side effects is recommended.

5. Advanced patient age or presence of severe comorbidities: In elderly patients or those with serious comorbid conditions such as cardiovascular disease or diabetes, chemoradiotherapy may increase the risk of treatment-related complications.

As each patient's condition is unique, treatment approaches should be individualized. Physicians will develop personalized treatment plans based on the specific circumstances of each patient. If any discomfort or symptoms arise, prompt medical consultation is advised.