Distance Matters: Correlation of Hepatocellular Carcinoma Nodule Distance to Overall Survival.

INTRODUCTION: Hepatocellular carcinoma (HCC) may occur with several simultaneous tumor foci in the liver (multifocal HCC). Molecular biology indicated that the larger the distance between two tumor nodules, the more those two nodules differed in their genetic composition. Therefore, we explored whether the overall survival (OS) of patients with HCC depends on the mutual distance of the HCC nodules. METHODS: In a retrospective study of 92 patients, CT/MRI images and survival data of the patients were collected. Based on the CT or MRI images at the time of diagnosis, the size of each tumor, the distance between the centers (center distance), and adjacent edges (edge distance) of the tumor nodules were measured, respectively. These data, combined with the number of tumor nodules and clinical characteristics, were compared with the patient's OS data. RESULTS: As expected, the average tumor diameter was significantly associated with patient survival in univariate Cox regression analysis (p = 0.00028, hazard ratio [HR] = 1.2). However, in multivariate analysis, the average center distance (p = 0.036, HR = 1.18) and average edge distance (p = 0.033, HR = 0.84) were also significantly associated with survival. CONCLUSION: Thus, not only the size of multiple HCC lesions but also their distance is important for the prognosis of patients with HCC. This may be of particular interest in patients with two nodules and BCLC B and C stages for the selection of therapeutic modalities and/or procedures.