Breast cancer diagnosis could be made much faster soon by linking specialists across the globe using the Internet and a virtual microscope.
An Internet tool called the Virtual Pathology Slide which can display tissue samples taken from breast cancer patients is being developed by scientists at Dublin City University. This will allow on-line, remote diagnosis in minutes rather than days as medics can compare notes on samples wherever they are as long as they have access to the World Wide Web.
Highly detailed images taken from tissue samples are prepared for an interactive, telepathology web site giving a range of magnifications from 16 to 2000 times. The project is led by Dr Donal O'Shea in the School of Biotechnology at DCU and Prof Peter Dervan of the Mater Hospital, Dublin. Funding for the project comes from the Health Research Board.
"Better screening of breast cancer has led to an increased awareness of early forms of the disease," explained Dr O'Shea. One of these forms is known as ductal carcinoma in situ (DCIS) This is a preinvasive form of the cancer in which the cancerous changes are confined to the milk ducts supplying the nipple.
Because DCIS is an early sign of cancer, doctors are looking for treatments less radical than mastectomy, the removal of the affected breast. The extent of surgery to take away diseased tissue and an amount of surrounding normal tissue for safety will depend on the grade of the cancer. "A lot of discussion on the treatment of DCIS rests on the basis of the pathology and if agreement can be reached as to whether it is low or high grade," explained Dr O'Shea.
The current practice can be slow. "In a grading study, a pathologist would normally receive a slide by post. A form would have to be filled-in and then returned. This gives potentially long lead times for decisions." This new online method of inspecting the tissue samples could allow consensus to be reached much more quickly.
The system developed at DCU loads scanned images of tissue slides onto the telepathology website. Each tissue slide measuring 15.5 by 11.6 millimetres actually represents a collection of 35,000 images. Using a conventional web browser, the user is able to click on the image to see enlargements of any region up to a maximum of 2,000 times magnification.
It is a step forward from other telepathology systems in that it allows the user to select any view of a sample and removes any subjective pre-selection of views by an individual pathologist, according to its developers. "This is fundamentally a unique tool in terms of scale, robustness and deployment," said Dr O'Shea.
At present, up to 30 hours are needed to prepare the large number of images for each virtual pathology slide. Roughly two gigabytes of computer storage space per slide are needed and the current system is limited by the time taken to scan the images and upload them to the web server. Dr O'Shea and his team are working on an improved system with a more powerful computer which should allow one slide to be prepared in a single working day.
As well as being used for remote diagnosis the Virtual Pathology Slide will be used for training and assessment of pathology specialists. "Pathology is as much an art as a science," said Dr O'Shea. "The old teach the young in a very subjective way. Even expert pathologists are assessed quite regularly."
The Virtual Pathology Slide lets students examine an entire tissue sample slide and the system records their movements. This provides a more comprehensive insight into the individual's examination technique and also permits correlation with other experts.