The title for today’s blog has been adapted from an editorial highlighting a paper that appeared this week in Science Translational Medicine, a journal published by the American Association for the Advancement of Science (AAAS). Entitled “CytoPAN – portable cellular analyses for rapid point-of-care cancer diagnosis,” the article describes an innovative medical device developed by a diverse group of scientists from Korea, Singapore and the USA. As the editor commented, “Accurate and timely diagnosis and categorization of cancer are not always simple, even under optimal conditions. It can be nearly impossible in the developing world, where biopsy results can take months to return.”
The CytoPAN system was developed according to criteria recommended by the WHO for evaluating point-of-care (POC) devices in resource-limited settings – ASSURED, which is an acronym for “affordable, sensitive, specific, user-friendly, rapid, equipment that is deliverable to end-users.” CytoPAN is an imaging system that measures cells and enables automated and same-day molecular analysis of fine needle aspiration (FNA) of palpable breast lesions. Unlike a core biopsy, which requires specialised instrumentation, FNA is a minimally invasive technique that can be performed with a single needle pass (seen above left).
The schematic on the right (© AAAS) illustrates the CytoPAN workflow: (1) cellular samples acquired from patients via FNA; (2) harvested cells are briefly fixed and rendered permeable; (3) samples are processed using prefabricated reagent kits with antibodies for breast cancer diagnosis; (4) stained cells are analysed by the imaging device (seen below left) that contains no moving parts; (5) customized algorithms perform automated analysis to separate host cells from cancer cells and extract cancer subtype information; and (6) final diagnostic report displays quantitative information, including cancer cell population and molecular subtypes.
The researchers performed extensive optimization and validation of CytoPAN using established cancer cell lines and mouse models. As indicated in the diagram above right, they were able to establish breast cancer diagnosis and subtyping in less than one hour, using as few as 50 harvested cells. In a prospective study of 68 patients, their diagnostic accuracy was 100% for cancer detection with greater than 93% accuracy for subtyping.
The component cost for the CytoPAN device is $3,420, while the cost of the reagent test kit is $4.87, which means that the technology could potentially be made widely available in low- and middle-income countries. Given that breast screening programmes do not exist in many of these countries, CytoPAN could be a game-changer in treating women who palpate a breast lump. Clearly, this medical device is panning for diagnostic gold.