Neoadjuvant chemotherapy prior to definitive radical surgery or radiotherapy may be effective in reducing tumor volume or clinical stage and may even enhance pelvic control and survival. However, there are significant limitations to the use of
neoadjuvant therapy in non-responder group. They include delayed total treatment course, presence of drug resistant clones which result in accelerated tumor growth, and limited bone marrow reserve for subsequent definitive therapy. Thus, there is
a
need
to identify parameters providing a more precise indication of the response to neoadjuvant chemotherapy.
From Jan. 1995 to Jan. 1996, neoadjuvant chemotherapy with 3 courses cisplatin and vincristine was used in 32 patients with invasive cervical cancer(FIGO stage Ib to IIIb; tumor size greater than 2 cm). Prior to chemotherapy, quantitative tissue
levels
of epidermal growth factor receptor(EGFT) and c-erbB-2 oncogene protein were measured by using an enzyme-linked immunosorbent assay(ELISA). Also, sera from patients were evaluated for squamous cell carcinoma(SCC) antigen by using a
radioimmunoassay(RIA)
and for urine polyamine by creatinine enzyme method. Tumor size was estimate before and after chemotherapy. Relations among oncoproteins, tumor markers and reductions of tumor size were evaluated. Tumor size prior to neoadjuvant chemotherapy did
not
show any correlation either with the concentrations of EGFR and c-erbB-2 oncoprotein or with levels of serum SCC antigen and urine polyamine. Also, reduction rate of tumor mass did not manifest correlation with EGFR, SCC antigen and urine
polymine.
However, reduction rate of tumor mass had an inverse linear correlation with the c-erbB-2 oncoprotein(Rs=-0.71, P<0.05).
The results of this study suggest that c-erbB-2 oncoprotein is associated with a reduced response to neoadjuvant chemotherapy in primary treatment of invasive cervical cancer and may be useful in directing therapeutic approaches.
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