Deferred Systemic Therapy Following Destructive Local Treatment of Pulmonary Oligometastases After NED in Colorectal Cancer： A Phase II, Single-Arm Clinical Trail.
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.
• Patients with a pathologically confirmed diagnosis of colorectal cancer with the following disease conditions:
‣ 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.
⁃ No prior radiotherapy to the lungs.
• RECIST 1.1 criteria: The patient must have measurable lesions, defined as at least one nodal lesion with a longest diameter \> 1.5 cm, or at least one nodal lesion \> 1 cm with an accurately measurable pendulous diameter.
• ECOG performance status: ≤ 2 (Eastern Cooperative Oncology Group general condition score).
• The patient's expected survival must be ≥ 3 months.
• Adequate hematologic function: Absolute neutrophil count ≥ 1.6 x 10⁹/L, with no growth factor support for at least 7 days prior to testing.
• Normal organ function: The patient must be able to tolerate at least one of the local destructive treatments, as assessed by the corresponding department's physician, based on normal hepatic, renal, pulmonary, and cardiac function.
• Reproductive age: Female patients of childbearing potential must agree to use a reliable method of contraception with their partner from the time of informed consent until 1 year after treatment completion.
• The patient must have voluntarily provided informed consent to participate in the study.