Background: Bevacizumab is an agent with a tolerable safety profile which was described to be effective in recurrent ovarian cancer in recent phase I and phase II trials. But it remains unclear if these characteristics can translate to the very special collective of heavily pre-treated ovarian cancer patients. The present analysis was conducted to answer questions regarding safety and efficacy for the use of bevacizumab in these patients.
Patients and methods: A single-center, retrospective chart review was performed including all patients with histologically confirmed ovarian cancer and treatment with bevacizumab between 1981 and 2008. Data documentation was performed with an internet-based documentation tool (Alcedis Med, Alcedis, Gießen, Germany). All data were analyzed using SPSS version 16.0 (SPSS Inc., Chicago, IL, USA).
Results: Overall, 15 patients who were treated with bevacizumab outside of a clinical study were identified. A total of 134 cycles of bevacizumab were applied, with a median of 8.9 cycles per patient. All 15 patients had platinum-resistant disease at the time of treatment, with a median of 5.4 prior lines of chemotherapy (range 1-7). The best response under treatment with bevacizumab was classified as partial response in 2 patients (13.3%). Stable disease was found in 6 (40%) and progressive disease in 7 (46.7%) patients. The median time to progression was 6.6 months and the median overall survival was 15.0 months from the first cycle of bevacizumab. At the time of analysis 3 patients were still alive and 1 patient had been lost to follow-up. No gastrointestinal perforations or treatment related deaths were observed. Severe adverse events included 3 fistulas (20%), 1 impaired wound healing (6.6%) and 1 severe blood pressure crisis (6.6 %).
Discussion: Despite previous experience of a high rate of bowel perforations in patients with ovarian cancer treated with bevacizumab, no perforation was observed in this analysis despite the fact that this collective was a heavily pretreated and platinum resistant subgroup. The most severe possible side effect in this group was the occurrence of fistula, which might suggest that bevacizumab is a therapy option with an acceptable safety profile, even though the rate of fistulas is higher than reported in previous studies. This might again be related to the nature of this very special subgroup of heavily pretreated patients.
Conclusion: The results of this analysis suggest that bevacizumab might be an efficient therapy option in the setting of heavily pre-treated ovarian cancer with a tolerable safety profile even in this very special collective.