An objective biochemical assessment of therapeutic response in metastatic breast cancer: a study with external review of clinical data

Abstract

Summary A series of tumour related markers have been examined in 179 patients receiving primary endocrine therapy for metastatic breast cancer. Significant correlations between therapeutic response (UICC criteria after 6 months of treatment) and appropriate alterations in serum concentrations of carcinoembryonic antigen, ferritin, c-reactive protein, orosomucoid and the erythrocyte sedimentation rate, have been observed when changes in these markers were examined only at high serum concentrations. By combining these five markers a 'therapeutic index' of response has been devised which can be employed at an early stage of treatment in more than 90% of patients, giving an overall sensitivity/specificity of 90%/78% for therapeutic response or disease stabilisation over a 6-month period. The design of an objective measurement of response, which is easy to perform, has the potential to replace the existing, largely subjective, UICC criteria for retrospective judgement of response, and may also be used to direct systemic endocrine therapy.

Continuous chemotherapy in responsive metastatic breast cancer: a role for tumour markers?

“…We have confirmed that the biochemical index derived for patients receiving first-line endocrine therapy (Williams et al, 1990;Robertson et al, 1992) is also applicable to patients treated by chemotherapy. A highly significant correlation was observed between the 3 and 6 month UICC response assessments and changes in biochemical index (CEA, CA 15.3 and ESR) calculated after 6-8 and 12-16 weeks of chemotherapy.…”

“…The previously set cut-off values (see Table I) were used for all three markers (ie. CEA 6 ng ml-', CA 15.3 33 U ml-' and ESR 20 mm h-1); marker changes from the baseline value of > ± 10% were regarded as significant (Williams et al, 1990;Robertson et al, 1992). Using the three markers in combination 55 of 57 UICC assessable patients with systemic breast cancer were biochemically assessable (96%).…”

“…Biochemical assessment of response The biochemical score was calculated in the same manner as described for the first-line endocrine studies (Williams et al, 1990;Robertson et al, 1992). Namely, any change in marker whilst the patient is on therapy is related to the pretreatment value.…”

“…Very few studies have looked at combinations in measuring response to therapy. On retrospective and prospective analyses we have shown that changes in CEA, ESR and CA 15.3 individually correlate with therapeutic response in patients with metastatic breast cancer treated by first-line hormones (Williams et al, 1990;Robertson et al, 1992). In a prospective study, 93% of patients were assessable with a sensitivity for response of 92% and specificity 82% (Robertson et al, 1992).…”

Objective measurement of therapeutic response in breast cancer using tumour markers

“…In Nottingham we have previously shown in a retrospective analysis (Williams et al, 1990) and prospectively confirmed (Nicholson et al, 1981;Nicholson et al, 1986 (Hayward et al, 1977). Three patients were unassessable for response by UICC criteria.…”