Katie Weimer, a Colorado-based biomechanical engineer, is transforming breast cancer recovery with a groundbreaking approach to reconstruction using 3D-printed biotissue. The idea, she says, was sparked decades ago by the loss of her mother to breast cancer when Weimer was just 15.
“Many women live every day with a reminder of the cancer they had,” said Weimer, 43. “That is not good enough. There must be a better way.”
Weimer envisions a future where breast cancer survivors can regain not only their health but also their dignity. Her startup, GenesisTissue, aims to develop bio-friendly, 3D-printed breast tissue scaffolds that integrate a patient’s own fat cells, allowing natural tissue to regenerate after a lumpectomy or mastectomy.
Currently, over 300,000 women in the United States are diagnosed with breast cancer annually, with 40,000 deaths, according to the American Cancer Society. Globally, an estimated 2.3 million women receive a breast cancer diagnosis each year, resulting in nearly 670,000 deaths, according to the World Health Organization. Standard treatments often leave survivors with permanent scarring or deformities, which can have profound psychological effects.
“We treat the disease, but not the deformity,” Weimer said. “Doctors do a good job removing cancer, but women are left with a divot in their breast. That has huge impacts.”
GenesisTissue’s approach involves creating personalized scaffolds from advanced, bioprintable materials. Surgeons extract a patient’s fat cells via liposuction and inject them into the scaffold. Once implanted, the cells grow into natural tissue, while the scaffold gradually dissolves, leaving the patient’s own tissue to restore breast shape.
“The ideal solution would be to implant the scaffold at the time of cancer tissue removal,” Weimer said. “It allows the patient’s body to heal itself and the surgeon to play a more active role in reconstruction beyond removing cancer.”
Unlike traditional silicone or saline implants—which carry FDA warnings about potential cancer risks—Weimer’s method uses a patient’s own cells, reducing the risk of long-term rejection. Each scaffold is custom-designed using computer scans of the patient’s tumor, ensuring precise fit and functionality.
Preclinical studies and benchtop data show promising results, and Weimer hopes these will pave the way for clinical trials. “At GenesisTissue, we work every day for breast cancer survivors and their right to a reconstruction that regenerates their own tissue—and lasts a lifetime,” she said.
The technology builds on advances in regenerative medicine and bioprinting, which have recently achieved milestones such as 3D-printed windpipes in South Korea and patient-specific livers at UC San Diego. In breast reconstruction, Harvard researchers and companies like Lattice Medical are exploring vascularized, 3D-printed tissue.
Weimer, who has been involved in 3D printing for surgical planning since 2007, is no stranger to high-stakes innovation. She helped guide surgeons using 3D-printed models during the historic 27-hour separation surgery of conjoined twins Jadon and Anias McDonald in 2016.
“She’s one of the most talented biomedical engineers I’ve ever met,” said Dr. Oren Tepper, a plastic surgeon who worked with Weimer on multiple cases. “Her expertise not only lies in 3D printing but in applying it to improve patient care.”
Weimer credits her mentor, Charles Hull, inventor of 3D printing, for encouraging her to use her skills to benefit humanity. “She’s made a career out of helping people,” Hull said.
For Weimer, her work is personal. “My mother’s life, illness, and selflessness are a big reason why I believe innovation matters,” she said. “Nearly 30 years later, I see how her cancer journey shaped my career. Losing her was transformative, and I hope my work will transform the lives of women everywhere.”
