Glutathione S-transferase pi immunostaining of cisplatin-resistant ovarian cancer cells in ascites

Acta Cytol. Nov-Dec 1998;42(6):1397-402. doi: 10.1159/000332174.


Objective: To clarify immunohistochemically the correlation between glutathione S-transferase pi (GST pi) expression of surgically resected specimens and clinical response in ovarian cancer and to evaluate ascites cytology using GST pi staining.

Study design: Eighty-seven patients with ovarian cancer underwent initial debulking surgery and received cisplatin-based chemotherapy after surgery. Immunostaining for GST pi was performed on formalin-fixed sections of the patients' tumors. The cytologic slides of 24 cases were acquired for evaluation of GST pi staining.

Results: Of 87 surgically resected specimens, 55 (63.2%) were GST pi positive. Twenty-five of 28 patients (89.3%) who showed no response to chemotherapy had GST pi-positive tumor cells. The predictive value of positive GST pi staining for drug resistance was 75.8% (25/33). Of 18 cases that were GST pi positive in surgically resected specimens, 17 were positive in ascites cytology. Five cases were negative in both resected specimens and ascites cytology. There was a significant correlation in the GST pi labelling index between resected specimen and ascites cytology from the same case; the correlation coefficient was .701 and P value < .001.

Conclusion: Overexpression of GST pi is related to resistance to cisplatin, and GST pi staining of ascites cytology can be used in pretherapeutic assessment of patients with ovarian cancer.

MeSH terms

  • Adult
  • Antineoplastic Agents / administration & dosage*
  • Ascites / enzymology
  • Ascites / pathology
  • Cisplatin / administration & dosage*
  • Cystadenocarcinoma / enzymology
  • Cystadenocarcinoma / pathology*
  • Cystadenocarcinoma / surgery
  • Drug Resistance, Neoplasm
  • Female
  • Glutathione Transferase / analysis*
  • Glutathione Transferase / immunology
  • Humans
  • Immunohistochemistry
  • Middle Aged
  • Ovarian Neoplasms / enzymology
  • Ovarian Neoplasms / pathology*
  • Ovarian Neoplasms / surgery


  • Antineoplastic Agents
  • Glutathione Transferase
  • Cisplatin