This Week's ETF Winners & Losers

The HealthShares Emerging Cancer(HHJ Quote) exchange-traded fund was one of the best performers of the holiday-shortened week. Dendreon (DNDN Quote) has surged 245% over the last five sessions. Last Friday, the Food and Drug Administration said the company's prostate cancer vaccine treatment, Provenge, was safe and effective in treating prostate cancer, sending the stock soaring. The ETF finished the week higher by 8.2% to $27.

ETFs tracking metals and mining were also among the week's winners. Gold futures gained nearly 2.5% over the four sessions, and silver futures rose 2.2%.

For the week, the iShares Silver Trust(SLV Quote) was higher by 2.3% to $136.60. The streetTRACKS Gold Shares(GLD Quote) ETF added 1.7% to $66.84. The iShares Comex Gold Trust(IAU Quote) tacked on 1.6% to $66.88.

Utility-related ETFs also gained ground during the week. Among individual names, Entergy(ETR Quote), Exelon(EXC Quote), FirstEnergy(FE Quote) and Public Service Enterprise Group(PEG Quote) climbed by 2.5% or more.

The Utilities Select Sector SPDR(XLU Quote) ETF tacked on 2.4% to $40.67. The Utilities HOLDRs(UTH Quote) ETF was higher by 2.1% to $143.81. The iShares Dow Jones US Utilities(IDU Quote) ETF added 1.9% to $98.91.

On the flip side, bundled securities tracking the energy sector were among the worst performers of the week. On Wednesday, Iran's President Mahmoud Ahmadinejad decided to free 15 British sailors and marines it captured last month in the Persian Gulf. Crude prices, which spiked after the British were initially captured, slumped 2.4% to finish the week at $64.28 a barrel.

The iPath Goldman Sachs Crude Oil Index(OIL Quote) ETF eased 2.6% to $37.99. The United States Oil(USO Quote) ETF fell 2.5% to $52.01.