Growth index, assessed with Ki-67 and ssDNA labeling; a significant prognosticator for patients undergoing curative resection for hepatocellular carcinoma

Background and Objectives: The aggressiveness and greater malignant potential of cancers are characterized by several biological phenomena such as accelerated growth invasiveness, and the ability to form distant metastasis. Thus, knowledge of such biological difference may be a more accurate prognosticator for cancer patients. Tumor growth depends on the degree of imbalance between cell production and loss. This study aimed to clarify a possible role for the modified prognosticator, growth index (GI); defined as the difference between Ki-67 (%) and single-stranded DNA (ssDNA) (%) labeling indices, in patients undergoing curative resection for hepatocellular carcinoma (HCC). Methods: Tissue specimens were obtained from 40 HCC patients who underwent curative surgery. Immunohistochemical staining was performed using the avidin-biotin-peroxidase-complex method. Results: The GI in HCC ranged from -1.90% to 28.65%, median 3.73. GI was related to histologic grade, intrahepatic metastasis, and pathologic T stage. Cumulative survival was poorer in patients with higher GI (>= median value). Multivariate analysis demonstrated that GI is an independent prognosticator along with vascular invasion and intrahepatic metastasis. Conclusions: The higher GI values were significantly associated with histologic aggressive features of HCCs, and GI was a significant independent prognosticator in HCC patients after curative resection.