Management of disappearing colorectal liver metastases: an international survey.

BACKGROUND Improved chemotherapy response rates have lead to "disappearing" colorectal liver metastases (dCRLM). We aim to assess management patterns of dCRLM from an international body of hepatobiliary surgeons. METHODS A survey was designed, tested for item relevance, readability and content validity, and distributed to the AHPBA, IHPBA and ANZHPBA. RESULTS The majority of 226 respondents were 50% of their practice to hepatobiliary (75%). Surgeons utilize CT(45%) or MRI(47%) for preoperative planning with a preferred imaging interval of <6 weeks. Nearly all have experienced dCRLM (99%) and 63% of surgeons have waited a few months to assess for durability of response prior to definitive surgical/ablative therapy. Only 24% place fiducial markers for lesions <1-cm prior to neoadjuvant chemotherapy. Intra-operatively, 97% of surgeons perform ultrasound, and 71% ablation. When a tumor has "disappeared," 49% elect for observation and 31% resect if the dCRLM is superficial. Of those electing observation, 87% believe there is effective treatment with progression on surveillance imaging. CONCLUSIONS Nearly all surgeons have experienced dCRLM with half choosing observation over intervention due to the belief that these lesions may be re-addressed in the future.