Salvage therapy with topotecan in heavily pretreated ovarian cancer patients

Clinical Significance of CA125 Level after the First Cycle of Chemotherapy on Survival of Patients with Advanced Ovarian Cancer

PURPOSE

To determine the most powerful cancer antigen 125 (CA125)-related prognostic factor for advanced epithelial ovarian cancer (EOC) and to identify cut-off values that distinguish patients with a poor prognosis from those with a good prognosis.

MATERIALS AND METHODS

We included 223 patients who received staging laparotomy and were diagnosed with stage IIC-IV serous EOC. Cox regression analysis was used to determine the most significant prognostic factor among the following variables: serum CA125 before surgery and after the first, second, and sixth cycles of chemotherapy; the nadir CA125 value; the relative percentage change in CA125 levels after the first and second cycles of chemotherapy compared to baseline CA125; CA125 half-life; time to nadir; and time to normalization of the CA125 level.

RESULTS

The CA125 level after the first chemotherapy cycle was the most significant independent prognostic factor for overall survival (OS). Time to normalization (p=0.028) and relative percentage change between CA125 levels at baseline and after the first chemotherapy cycle (p=0.021) were additional independent prognostic factors in terms of OS. The CA125 level after the first chemotherapy cycle (p=0.001) and time to normalization (p<0.001) were identified as independent prognostic factors for progression free survival (PFS).

CONCLUSION

Among well-established CA125-related prognostic factors, serum CA125 levels after the first cycle of chemotherapy and time to normalization were the most significant prognostic factors for both OS and PFS.

Phase I and pharmacological study of pazopanib in combination with oral topotecan in patients with advanced solid tumours

Background:

This phase I study evaluated the safety, tolerability, maximum tolerated dose (MTD) and pharmacokinetics of two dosing schedules of oral topotecan in combination with pazopanib in patients with advanced solid tumours.

Methods:

Stage I of this study was to determine whether there was an impact of pazopanib on topotecan exposure. In stage II, the MTD and safety profile of oral topotecan given weekly on days 1, 8 and 15 in a 28-day cycle; or daily-times-five on days 1–5 in a 21-day cycle, both in combination with daily pazopanib, were explored.

Results:

In total, 67 patients were enroled. Pazopanib co-administration caused a substantial increase in exposure to total topotecan (1.7-fold) compared with topotecan alone, which is considered clinically relevant. Topotecan had no effect on pazopanib concentrations. Safety findings were consistent with the known profile of both agents. There were three drug-related deaths, liver failure, tumour haemorrhage and myelosuppression. Two patients experienced dose-limiting toxicities (DLTs; hand–foot syndrome, myelosuppression and diarrhoea) on the weekly topotecan schedule and four patients experienced DLTs (myelosuppression) on the daily-times-five topotecan schedule. When combined with pazopanib, 800 mg daily, the recommended doses for oral topotecan are: 8 mg weekly and 2.5 mg daily-times-five. Seven of eight patients with partial response had platinum-resistant ovarian cancer. In addition, 54% of patients had stable disease with 22% stable for 6 months.

Conclusions:

Total topotecan exposure is 1.7-fold higher when co-administered with pazopanib. Both schedules of administration were tolerated and would permit further evaluation, especially the weekly schedule.

A critical review of the analytical approaches for circulating tumor biomarker kinetics during treatment

Changes in serum tumor biomarkers may indicate treatment efficacy. Traditional tumor markers may soon be replaced by novel serum biomarkers, such as circulating tumor cells (CTCs) or circulating tumor nucleic acids. Given their promising predictive values, studies of their kinetics are warranted. Many methodologies meant to assess kinetics of traditional marker kinetics during anticancer treatment have been reported. Here, we review the methodologies, the advantages and the limitations of the analytical approaches reported in the literature. Strategies based on a single time point were first used (baseline value, normalization, nadir, threshold at a time t), followed by approaches based on two or more time points [half-life (HL), percentage decrease, time-to-events…]. Heterogeneities in methodologies and lack of consideration of inter- and intra-individual variability may account for the inconsistencies and the poor utility in routine. More recently, strategies based on a population kinetics approach and mathematical modeling have been reported. The identification of equations describing individual kinetic profiles of biomarkers may be an alternative strategy despite its complexity and higher number of necessary measurements. Validation studies are required. Efforts should be made to standardize biomarker kinetic analysis methodologies to ensure the optimized development of novel serum biomarkers and avoid the pitfalls of traditional markers.

Allogeneic hematopoietic stem cell transplantation in ovarian cancer-the EBMT experience

Although preliminary results suggest that allogeneic hematopoietic stem cell transplantation (allo HCT) for ovarian cancer (OC) is a feasible procedure, the low patient number in previous studies had limited ability to evaluate the true benefit of allo HCT in OC. This retrospective multicenter study included 30 patients with OC allografted between 1995 and 2005 to determine the outcome of patients with OC treated with allo HCT. Prior to allo HCT, patients were in complete response (n = 1), partial response (n = 7), stable disease (n = 11) or had progressive disease (n = 13). An objective response (OR) was observed in 50% (95% CI, 33-67) of patients. Three patients of responding patients had an objective response following the development of acute graft-versus-host disease (aGvHD). The cumulative incidence of chronic GvHD (cGVHD) was 34% (95% CI, 18-50). Transplant relative mortality rates were 7 and 20% on day 100 and 1 year, respectively. With a median follow-up of 74.5 months (range 16-148), median progression free survival (PFS) was 6 months and median overall survival (OS) was 10.4 months. Patients who developed cGvHD following allo HCT had a significant OS improvement compared to those who did not (17.6 months vs. 6.5 months, p = 0.042). However, PFS was not similarly significantly improved in patients who developed cGvHD (12 months versus 3.7 months, p = 0.81). Allo HCT in OC may lead to graft-versus-OC effects. Their clinical relevance remains to be shown.