A New Dimension: 3-D Printing Poised to Accelerate Progress in Cancer Research

The use of 3-D printing in medicine and in the research and treatment of cancer is in its infancy, but its implications are revolutionary.

Using a 3-D printer, early-stage research has included the creation of a 3-D model of a cancerous tumor made of fibrous proteins and cervical cancer cells, and a realistic 3-D representation of the tumor’s environment. In Spain, with the help of engineers and technology, doctors were able to print a 3-D prototype of a 5-year-old boy’s inoperable brain tumor, made out of resin, which they used to study and rehearse a surgical procedure that successfully removed the tumor without damage to surrounding tissue.

Some 3-D printers even have the ability to copy human tissue, such as that from tumors, creating models that can then be used to test the effectiveness of potential treatments for cancer, and the ability to print living, working human organs is evolving. This technology may eventually be applied to cancer medications; in August, for the first time, the U.S. Food and Drug Administration approved a pill, for epilepsy, that is manufactured via 3-D printing.

Invented over 30 years ago by Charles Hull, 3-D printing is a technology originally used to create prototypes of objects for manufacturing. The auto and airline industries, for example, were among the earliest adopters of 3-D printing, using the technology to test the form, fit and function of parts prior to mass manufacturing them for use in cars and planes. Today, due to the growing capabilities of 3-D printers, many companies have begun using the technology to produce end-use parts in materials including metals, plastics and nylons.

3D Systems, founded in 1986 by Hull and based in Rock Hill, South Carolina, pioneered the commercialization of 3-D printing technology that was later adopted by various companies. In medicine, the company has created technology to transform patient-specific data into anatomical models for surgical planning, and to use as guides and implants for surgical procedures.

3-D printing is the creation of a physical object made of one of many kinds of materials from a computer-aided design (CAD). Once the virtual design is created with computer software using a 3-D modeling program, it is sent to a printer, where the file is sliced and built layer by layer, from the bottom up, in three dimensions. All conceptual and design work takes place before printing, and instructions are sent from a computer to a printer.

In medicine, 3-D printing is most widely used to create custom-made equipment and medical products such as dental and other implants, prosthetics, anatomical models and tools. At MD Anderson Cancer Center in Houston, Matthew Hanasono, a professor of plastic surgery, is using 3-D printing to create parts for facial, head and neck reconstruction to replace those that have been damaged by cancer or cancer surgery. Hanasono says that images from CT scans of the head and neck are manipulated using CAD software specifically created for medical reconstruction to shape bone taken from the leg in order to restore a patient’s jaw and cheek, for instance. “Everything that was once done by hand, and thus by trial and error, can now be planned on a computer, and our research has shown that the technology minimizes operative time and improves accuracy,” Hanasono says.

At Memorial Sloan Kettering Cancer Center in New York, engineering and manufacturing can be done on site, where the hospital maintains its own machine shop. In collaboration with doctors, instruments and devices are being designed to improve the accuracy of procedures, and molds for bone replacement are being designed, printed and studied. One of the projects in development is the creation of a form-fitting shield to more accurately and comfortably direct radiation treatment to cancer patients. “Surgeons have ideas of the kinds of processes they want to use to operate in specific situations, and we work with them to design tools that might help them do that better,” says Paul Booth, of the hospital’s biomedical engineering lab.

At the Knight Cancer Institute at Oregon Health and Science University, Rosalie Sears, a professor in the department of molecular and medical genetics, is using a 3-D tissue bioprinter created by Organovo, a San Diego-based company, to replicate human tumor tissues that can then be grown in the lab. She is beginning to use those printed tumors to test various cancer-fighting treatments.

The future prospects for 3-D printing and its use in medicine, and particularly in cancer treatment, are vast. The work being done by Sears holds out enormous possibilities for more successful cancer therapy. A future next step would be the ability to individualize treatment by extracting an individual’s cancerous cells, printing them in 3-D in a lab, making multiple copies and testing them with various therapeutic and perhaps unique treatments.

Looking ahead, the possibilities for printing organs such as lungs, kidneys and livers could alleviate the long waiting times for a limited number of those organs available for transplant. Ideally, printing cartilage and bones out of human tissue instead of out of synthetic materials could further individualize medical treatment.

That kind of advancement would also mean a new need for approvals from the FDA: While approval is not required for a researcher to create printed tissue and use it to test cancer treatments, it is needed if a doctor plans to print tissue and use it as an implant or therapy in patients.

Sharon Presnell, chief technology officer at Organovo, believes that 3-D printing will herald a new medical paradigm. She predicts that, in decades to come, many scientific assumptions that have been made based on results from simple two-dimensional systems will be proven wrong.