Ovarian cancer – the fifth leading cause of death in women in the US – often goes undetected until it has spread elsewhere. But a new minimally invasive method that investigates cells taken from the neighboring cervix or uterus could provide early detection. The technique, developed by Vadim Backman, a professor of biomedical engineering at Northwestern University’s McCormick School of Engineering and Applied Science and a member of the university’s Robert H. Lurie Cancer Center, uses partial wave spectroscopic (PWS) microscopy to examine the architecture of cells at the nanoscale, detecting minute changes that are the earliest known signs of carcinogenesis. These changes can be seen in cells far from the tumor site – in a biological phenomenon known as the “field effect” – or even before a tumor forms. Vadim Backman of Northwestern University has developed a minimally invasive technique that examines cells swabbed from the cervix or uterus and that has the potential to detect the early presence of ovarian cancer. Courtesy of Northwestern. “We were surprised to discover we could see diagnostic changes in cells taken from the endocervix in patients who had ovarian cancer,” Backman said. “The advantage of nanocytology – and why we are so excited about it – is we don’t need to wait for a tumor to develop to detect cancer.” The study, conducted by researchers from Northwestern and NorthShore University HealthSystem, included 26 women, 11 with ovarian cancer and 15 who served as part of a control group. Cell samples were taken using a swab – similar to that of a Pap smear – and were placed on slides and examined using the light-scattering technique. The results showed a significant increase in the disorder of the nanostructure of epithelial cells obtained from cancer patients compared with controls for the endometrium and endocervix studies. Previous studies using PWS showed promising results in the early detection of colon, pancreatic and lung cancers using cells from neighboring organs. For the earlier lung cancer study, cells were brushed from the cheek. For the colon, cells came from the rectum, and for the pancreas, cells were obtained from the duodenum. “The changes we have seen in cells have been identical, no matter which organ we are studying,” Backman said. “We have stumbled upon a universal cell physiology that can help us detect difficult cancers early. If the changes are so universal, they must be very important.” If commercialized, PWS could be in clinical use for one or more cancers in about five years. The research was published in the International Journal of Cancer (doi: 10.1002/ijc.28122).