Colorectal cancer (CRC) is the third most common cancer worldwide. Surgical resection is one of the primary treatment options for CRC; however, postoperative recurrence remains a significant clinical challenge for both the medical community and patients. Postoperative chemotherapy, as an important adjuvant therapy, is widely used in CRC patients aiming to reduce the risk of recurrence. Despite extensive research on the efficacy of postoperative chemotherapy in CRC, the mechanisms of postoperative recurrence, predictive factors, and strategies to enhance chemotherapy effectiveness remain unclear. For colorectal cancer patients who have achieved NED (No Evidence of Disease), the decision to either reinitiate or change the systemic chemotherapy regimen for newly developed pulmonary oligometastases remains controversial. Local treatment options for diagnosing oligometastases include surgery, radiotherapy, and radiofrequency ablation. However, whether systemic treatment should be added after local treatment in patients who have achieved NED remains uncertain , and this issue requires urgent resolution.
The patient has achieved No Evidence of Disease (NED) after undergoing EMR, surgery, radiofrequency ablation, or radiotherapy.
NED has been maintained for ≥ 6 months.
The patient has not received chemotherapy, or has only received postoperative adjuvant chemotherapy or first-line systemic therapy.
Oligometastatic lung lesions (defined as 5 or fewer lesions) detected after ≥ 6 months of NED maintenance, eligible for destructive therapy.
First diagnosis of advanced colorectal cancer with metastatic disease.
Multiple lung metastases (> 5 lesions), liver metastasis, bone metastasis, or lymph node metastasis.
Lung metastases that are not amenable to radiotherapy, as determined by the investigator.
Previously received second-line or higher systemic treatment.