Impact of neoadjuvant chemotherapy on Ki-67 and PCNA labeling indices for esophageal squamous cell carcinomas

Purpose: The effects of neoadjuvant chemotherapy (CT) on Ki-67 and prolifer ating cell nuclear antigen (PCNA) labeling index (LI) were analyzed, using biopsy and surgical specimens of esophageal cancer, Method and Materials: Immunohistochemical staining for Ki-67 and PCNA was p erformed for biopsy and surgical specimens of 35 patients with esophageal s quamous cell carcinoma. Seventeen patients were treated with neoadjuvant CT (CT group), while no preoperative treatment was performed for tee remainin g 18 patients (control group). As neoadjuvant CT, cisplatin of 50 mg/body/w eek was administered 2-5 times (100-250 mg in total) until 7-10 days before subtotal esophagectomy, Result: Significant correlation between the LIs of biopsy and surgical spec imens was observed for the control group (p = 0.006 for Ki-67 and p = 0.005 for PCNA), although both LIs of surgical specimens were significantly high er than those of biopsy specimens (p < 0,05), However, no significant corre lation between LIs of biopsy specimens and those of surgical specimens was observed for the CT group. In addition, the LIs of the surgical specimens o f the CT group were significantly lower than the LIs of the control group ( p < 0.005 for Ki-67 and p < 0.05 for PCNA). Significant decrease in Ki-67 L I after neoadjuvant CT was noted especially for well or moderately differen tiated squamous cell carcinomas and/or tumors treated with high-dose cispla tin (150-250 mg). Conclusion: Significant correlation of Ki-67 and PCNA LIs between biopsy an d surgical specimens was demonstrated for the control group. Neoadjuvant CT decreased the percentage of cycling and proliferative tumor cells of esoph ageal cancer. (C) 2001 Elsevier Science Inc.