Xconomist of the Week: Peter Kuhn on Detecting Circulating Tumor Cells

Kuhn agreed to answer a few questions about the technology, and how broader advances in molecular diagnostics are expected to dovetail with the emerging fields of quantified health and personal medicine.

Xconomy: Does the type of primary tumor make any difference as a source for circulating tumor cells?

Peter Kuhn: We are only talking about the carcinomas—so the approximately 7 million Americans with breast, prostate, pancreatic, lung, ovarian, liver and kidney cancers. We have known for a very long time that cancer spreads through the blood. It’s just that we haven’t had the analytical tools to really track down the disease-derived cells. In terms of your question, we’re seeing different rates of cell [proliferation], and different types of cells in the different cases. In each case, [there is a] high degree of heterogeneity.

X: What’s the breakthrough that makes this possible?

PK: The set of fundamental breakthroughs intellectually was a) the recognition that there is a large degree of heterogeneity of these cells in the human blood, and b) being conscious of what it means to be dealing with the challenge of a needle-in-the-haystack type of problem.

Kelly Bethel and Peter Kuhn

We had to bring together deep vertical expertise in engineering and math with pathology and oncology. All parties had the simple unifying goal of doing something that could have real impact on individual patients at some point in the near future. The most important thing, you know, is to flip a challenge into an opportunity. That is what we did with the way we are preparing the samples as well as the way in which we are analyzing the data.

The analysis is a large-scale form of backend computing that has grown out of a longstanding collaboration with Microsoft. More and more, scientists are using fluorescently tagged antibodies to label particular proteins in cells. So we started using a very standard approach, of using these fluorescing antibodies to label these cells. Then we had to translate that into something that was technologically robust and that we could calibrate within and across sample.

X: How long have you been working on this?

PK: We began collecting the data that went into the papers two and a half years ago. We were funded with

Author: Bruce V. Bigelow

In Memoriam: Our dear friend Bruce V. Bigelow passed away on June 29, 2018. He was the editor of Xconomy San Diego from 2008 to 2018. Read more about his life and work here. Bruce Bigelow joined Xconomy from the business desk of the San Diego Union-Tribune. He was a member of the team of reporters who were awarded the 2006 Pulitzer Prize in National Reporting for uncovering bribes paid to San Diego Republican Rep. Randy “Duke” Cunningham in exchange for special legislation earmarks. He also shared a 2006 award for enterprise reporting from the Society of Business Editors and Writers for “In Harm’s Way,” an article about the extraordinary casualty rate among employees working in Iraq for San Diego’s Titan Corp. He has written extensively about the 2002 corporate accounting scandal at software goliath Peregrine Systems. He also was a Gerald Loeb Award finalist and National Headline Award winner for “The Toymaker,” a 14-part chronicle of a San Diego start-up company. He takes special satisfaction, though, that the series was included in the library for nonfiction narrative journalism at the Nieman Foundation for Journalism at Harvard University. Bigelow graduated from U.C. Berkeley in 1977 with a degree in English Literature and from the Columbia University Graduate School of Journalism in 1979. Before joining the Union-Tribune in 1990, he worked for the Associated Press in Los Angeles and The Kansas City Times.