Background: The most common site of colorectal extra-abdominal metastases is the lung. The relative risk of lung metastases after resection and cryotherapy has not previously been compared.
Methods: All patients underwent an extensive preoperative staging including clinical examination, abdominal computed tomography (CT) and abdominal angio-CT to assess their hepatic disease. Two groups of patients were compared in this study (hepatic resection alone and hepatic cryotherapy with or without resection). A retrospective analysis of prospectively collected data was performed to assess the incidence and disease-free interval of pulmonary metastasis after surgical treatment of colorectal liver metastasis.
Results: This paper clearly shows two differences regarding pulmonary metastases between patients treated with resection only and cryotherapy with or without resection. Among the 10 clinical variables, cryotherapy had the greatest correlation with pulmonary metastases (p=0.004). A patient who undergoes hepatic resection only has a probability of 35% for developing pulmonary recurrence, compared with 51% following cryotherapy. Cryotherapy was also independently associated with shorter pulmonary disease-free interval (p=0.036).
Conclusion: There clearly is a higher risk of pulmonary metastasis after cryotherapy than after resection, whether this is related to selection of patients or a direct deleterious procedural effect requires more study.