The value of immunohistochemical detection of P-glycoprotein in breast cancer before and after induction chemotherapy.
10.3349/ymj.1992.33.2.137
- Author:
Eun Hee KOH
1
;
Hyun Cheol CHUNG
;
Kyi Beom LEE
;
Ho Young LIM
;
Joo Hang KIM
;
Jae Kyung ROH
;
Jin Sik MIN
;
Kyung Sik LEE
;
Byung Soo KIM
Author Information
1. Department of Internal Medicine1, Yonsei University College of Medicine, Seoul, Korea.
- Publication Type:Original Article
- Keywords:
P-glycoprotein;
immunohistochemical stain
- MeSH:
Adult;
Aged;
Breast Neoplasms/chemistry/*drug therapy/pathology;
Breast Neoplasms/chemistry/*drug therapy/pathology;
Drug Resistance;
Drug Resistance;
Female;
Human;
Immunohistochemistry;
Membrane Glycoproteins/*analysis;
Middle Age;
P-Glycoprotein
- From:Yonsei Medical Journal
1992;33(2):137-142
- CountryRepublic of Korea
- Language:English
-
Abstract:
We have studied the patterns of P-glycoprotein expression before and after 3 cycles of induction chemotherapy (5-fluorouracil, adriamycin and cyclophosphamide) using immunohistochemically stained paraffin-embedded specimen of 28 patients with locally advanced breast cancer. The frequency of P-glycoprotein expression in untreated breast cancer turned out to be very low: only one out of 28 untreated, biopsy specimen at the time of diagnosis was positive. The frequency of P-glycoprotein expression was markedly increased from 9.1% before chemotherapy to 63.6% after induction chemotherapy (p = 0.006). After 3 cycles of induction chemotherapy, 25 patients had obtained clinical response to chemotherapy (4, CR; 21, PR). Eleven out of 25 tumors (44%) showing clinical response and all three tumors (100%) with minimal response have expressed P-glycoprotein. One out of 6 patients (16.7%) with microscopic residual tumor seen in mastectomy specimen expressed P-glycoprotein, whereas 13 of 22 patients (59.1%) with gross residual tumor showed the presence of P-glycoprotein (p = 0.08). The frequency of intrinsic P-glycoprotein expression in untreated breast cancer was quite low, but approximately half of the patients do acquire P-glycoprotein expression during the cycles of induction chemotherapy. Therefore, the results suggest that the immunohistochemical detection of P-glycoprotein on residual tumor cells after induction chemotherapy can predict acquired drug resistance in breast cancer.