Treatment and survival of patients with metachronous colorectal lung metastases

Introduction: The lungs are the second most common site for metachronous metastases in colorectal cancer. No treatment algorithm is established, and the role of adjuvant chemotherapy is unclear. This study aimed to map pulmonary recurrences in a modern multimodal treated population, and to evaluate survival depending on management. Methods: Retrospective study based on the COLOFOL-trial population of 2442 patients, radically resected for colorectal cancer stage II–III. All recurrences within 5 years were identified and medical records were scrutinized. Results: Of 165 (6.8%) patients developing lung metastases as first recurrence, 89 (54%) were confined to the lungs. Potentially curative treatment was possible in 62 (37%) cases, of which 33 with surgery only and 29 with surgery and chemotherapy combined. The 5-year overall survival (5-year OS) for all lung recurrences was 28%. In patients treated with chemotherapy only the 5-year OS was 7.5%, compared with 55% in patients treated with surgery, and 72% when surgery was combined with chemotherapy. Hazard ratio for mortality was 2.9 (95% confidence interval 1.40–6.10) for chemotherapy only compared to surgery. Conclusion: A high proportion of metachronous lung metastases after colorectal surgery were possible to resect, yielding good survival. The combination of surgery and chemotherapy might be advantageous for survival.