She says she was chilled by what she recalls her doctor saying: “There was so much growing so fast in my abdomen and so much in my bowel, it was not a matter of maybe I would get a bowel obstruction. It was when I would get a bowel obstruction,” Ms. Reeh said. “And when I got it, there would be nothing anyone could do. I would die.”

To try to stave off such a horrible outcome, her oncologist, Dr. Eric Winer of Dana-Farber, offered to enroll her in a clinical trial comparing Avastin with another new biotech drug. Ms. Reeh was assigned to the group that got Avastin in combination with the chemotherapy drug paclitaxel, also known as Taxol.

The study closed after six months, but Ms. Reeh continued with her drug regimen, and her insurer is paying. After six months of treatment the fluid in her abdomen was down to just a trace, her tumors were stable or smaller and she felt like her former self again.

“I’m really, really excited,” she said.

Was it the Avastin?

Dr. Winer said he did not know, since Taxol can also shrink tumors. It is impossible to draw conclusions from individual patients, he said. Still, he said, “I think it is quite likely that the combination of Taxol and Avastin improved her odds of having a better quality of life.”

Dr. Winer says that when he is not sitting in front of a patient, he thinks about whether drugs like Avastin are worth it to society. But when facing a seriously ill patient, who, based on clinical trial results, might benefit  even if only a little  from Avastin along with chemotherapy, he has to think about his patient’s needs.

“I can’t say, ‘Let’s not use Avastin; it’s a very expensive drug and I am worried about the cost to society,’ ” Dr. Winer said.

And so, Dr. Winer said, the answer you get when you ask whether drugs like Avastin are worth it very much depends on whom you ask.