Dave Danielsen

Giving surgeons a map they never had

Dave Danielsen runs a company built around a single, stubborn question about breast cancer surgery: why is the surgeon expected to remove a tumor she cannot actually see? As CEO of CairnSurgical, a clinical-stage medical device company in Lebanon, New Hampshire, he has spent the last several years answering it in hardware and software. The company’s Breast Cancer Locator System takes a patient’s own imaging and turns it into a custom, 3D-printed form that fits that one breast and guides the surgeon to the exact edges of the cancer.

Danielsen likes to put the problem in plain terms. “Just imagine being told, ‘Go get this tumor out, but you’re not allowed to see what shape and what size it looks like in that patient,’” he has said. “Well, now we’re letting them look at it ahead of time.” The pitch is not about a flashier operating room. It is about a woman not having to come back for a second surgery because cancer cells were left behind at the margins.

CairnSurgical spun out of Dartmouth in 2015, founded by surgeon Dr. Richard J. Barth Jr. and engineers Keith D. Paulsen and Venkat Krishnaswamy. The science came from the lab. Danielsen’s job has been to turn it into a product that surgeons trust, regulators approve, and hospitals can actually afford to use. That is the less glamorous half of medtech, and it is the half he has spent his career doing.

From scan to surgical guide

The Breast Cancer Locator System has two parts that work together: a physical, single-use 3D-printed form and visualization software that lets the surgical team study the tumor’s size, shape, and location before the first incision. The result is a guide built for exactly one patient and used exactly once.

What the results show

A study published in Annals of Surgical Oncology reported that surgeons using the BCL System achieved negative margins — no cancer cells at the removed tumor’s edges — in 94% of patients. In lumpectomy terms, cleaner margins mean fewer patients sent back to the operating room. That clinical outcome is also the economic argument Danielsen makes to investors and hospitals alike.

West Point, Tuck, and a career in commercializing science

Danielsen’s route to medtech is not the standard one. He is a graduate of the United States Military Academy at West Point, and he later earned an MBA from Dartmouth’s Tuck School of Business. That Dartmouth connection has a nice symmetry: he now leads a company that spun out of the same institution.

Before CairnSurgical, he held leadership and commercial roles across health and diagnostics companies, including as CEO of CRA Health, where he worked on advanced breast health software for clinical decision-making, and CEO of CPR Therapeutics. Earlier in his career he spent time at diagnostics and device companies including Oxford Immunotec and Hologic. The common thread is commercialization — taking a technical product and building the trial data, the regulatory case, and the go-to-market around it.

Notes and quirks

• He frames the entire problem with a thought experiment: asking a surgeon to remove a tumor without being allowed to see its size or shape first.
• The company name evokes a cairn, the stacked-stone trail marker — a quiet fit for a product built around guiding surgeons to a precise spot.
• CairnSurgical is headquartered in Lebanon, New Hampshire, well outside the usual Boston and Bay Area medtech clusters.
• He went to market in Europe first, while still working the U.S. FDA pathway — a sequencing choice that says a lot about how he balances speed and regulation.