Overcoming platinum resistance in ovarian carcinoma

Ovarian cancer remains a deadly malignancy because most patients develop recurrent disease that is resistant to chemotherapy, including platinum. Because response rates for current treatment regimens are relatively similar and unfortunately low, no standard chemotherapy for platinum-resistant ovarian cancer exists.

A systematic literature review of clinical studies published between January 2005 and March 2010 was conducted using search engines, PubMed and MEDLINE with the entry keywords 'ovarian cancer' and 'platinum resistance'. This search revealed 40 clinical trials (1793 patients).

Gemcitabine was the most common drug used in clinical trials reporting higher response rates, ≥ +1 SD of overall response rate (5 out of 8). Gemcitabine-based combination therapy showed an average response rate of 27.2% (95% CI, 22.4-32.0). Combination of gemcitabine and pegylated liposomal doxorubicin (PLD) was the most common regimen (n = 3) and was associated with possible additive effects in platinum-resistant ovarian cancer patients: response rate, gemcitabine alone 6.1%, PLD alone 19.8%, and gemcitabine with PLD 28.7% (95% CI, 20.4-37.0), respectively.

Analysis of recent clinical trials showed that gemcitabine-based combination chemotherapy was associated with the highest antitumor effects in platinum-resistant ovarian cancer patients during the study period.