Dr Choti and his coauthors have analyzed intraoperative sonographic findings of the liver in 99 consecutive patients with 194 metastatic colon tumors. Echogenicity and sonographic patterns were compared between patients and within each patient. There was notable variability in echogenicity and patterns among the lesions and the only clinicopathologic correlate was that of chemotherapy with a “target” or calcified pattern. Using the 40 patients with multiple tumors, it was found that there was much less variability within each patient (intrapatient variability) than would be expected from the variability between different patients (interpatient variability). Although this seems intuitive, the article clearly and objectively proves the point. There may not have been enough data in this series, but it would have been interesting to see if factors such as preoperative chemotherapy and/or hepatic steatosis correlated with intrapatient differences in sonographic features. The ultimate conclusion of this article is that these results will help the surgeon interpret sonographically detected lesions in the operating room. Patients with occult lesions of similar echogenicity and pattern to the known malignant lesion are more likely to be related. A clinically relevant example of this would be a hyperechoic tumor presumed to be a hemangioma in the setting of a known hyperechoic metastasis. While Choti et al have provided a complete and unique analysis of the sonographic features of hepatic metastases, perhaps the real value of this article is to point out what surgeons should practice anyway, that is, in the context of hepatic metastases, any and all palpable or sonographically occult hepatic tumors should be presumed to be malignant until proven otherwise.
D’Angelica M, Blumgart LH. Patient Variability in Intraoperative Ultrasonographic Characteristics of Colorectal Liver Metastases—Invited Critique. Arch Surg. 2008;143(1):35. doi:10.1001/archsurg.2007.6