Changes in Ca-125 relative to response following treatment with Pegylated Liposomal Doxorubicin (Caelyx®) in ovarian carcinoma


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Richard Turkington, Paula Scullin, Joanne Millar

Northern Ireland Cancer Centre, Belfast, Northern Ireland, UK

Abstract

Background

Reductions in Ca-125 are associated with an objective response to paclitaxel and platinum-based treatment but for patients treated withPegylated Liposomal Doxorubicin (Caelyx®) changes in Ca-125 levels may not be as closely correlated.

Method

Patients with recurrent ovarian carcinoma received Pegylated Liposomal Doxorubicin (Caelyx®) 50mg/m2 every 28 days and at the end of cycles 1 and 2 Ca-125 changes were categorized as baseline ± 10%, ± 11-25% or >25% variance. The Rustin criteria were also applied with two definition thresholds for respone: 50% reduction over four Ca-125 samples or a 75% reduction over three samples.

Results

A total of 52 patients were treated from 2003-2007 and 38 patients (73.1%) and 31 patients (59.6%) had serial Ca-125 measurements for evaluation after the first and second cycles respectively.

All patients responding to Caelyx demonstrated a decrease of more than 25% in Ca-125 at both cycles 1 and 2. For the patients with stable disease 58.3% (7/12) and 36.4% (4/11) showed an increase in Ca-125 after cycles 1 and 2 respectively. In patients with progressive disease 25% (6/24) and 38.9% (7/18) had a decrease in Ca-125 from baseline after cycle 1 and 2 respectively.

When analysed according to the Rustin criteria all responders were defined as such while 3 patients with stable disease and 1 with progressive disease were classified as responders.

Conclusion

Early changes in Ca-125 as measured by either percentage change or the Rustin criteria may not be representative of the ultimate response and should be interpreted with caution.

Background

Reductions in Ca-125 are associated with an objective response to paclitaxel and platinum-based treatment but for patients treated withPegylated Liposomal Doxorubicin (Caelyx®) changes in Ca-125 levels may not be as closely correlated.

Method

Patients with recurrent ovarian carcinoma received Pegylated Liposomal Doxorubicin (Caelyx®) 50mg/m2 every 28 days and at the end of cycles 1 and 2 Ca-125 changes were categorized as baseline ± 10%, ± 11-25% or >25% variance. The Rustin criteria were also applied with two definition thresholds for respone: 50% reduction over four Ca-125 samples or a 75% reduction over three samples.

Results

A total of 52 patients were treated from 2003-2007 and 38 patients (73.1%) and 31 patients (59.6%) had serial Ca-125 measurements for evaluation after the first and second cycles respectively.

All patients responding to Caelyx demonstrated a decrease of more than 25% in Ca-125 at both cycles 1 and 2. For the patients with stable disease 58.3% (7/12) and 36.4% (4/11) showed an increase in Ca-125 after cycles 1 and 2 respectively. In patients with progressive disease 25% (6/24) and 38.9% (7/18) had a decrease in Ca-125 from baseline after cycle 1 and 2 respectively.

When analysed according to the Rustin criteria all responders were defined as such while 3 patients with stable disease and 1 with progressive disease were classified as responders.

Conclusion

Early changes in Ca-125 as measured by either percentage change or the Rustin criteria may not be representative of the ultimate response and should be interpreted with caution.