A system designed for resource-limited settings provides rapid cancer profiling and requires “scant” cellular specimens, according to researchers.
The automated image cytometry system is called CytoPAN. In preclinical experiments, CytoPAN provided accurate cancer detection in 1 hour using as few as 50 cells.
In a prospective study of 68 breast cancer patients, CytoPAN detected cancer with 100% accuracy. The receptor subtyping accuracy was 96% for HER2 and 93% for estrogen and progesterone receptors.
Jouha Min, PhD, of Massachusetts General Hospital, Boston, and colleagues reported these findings in Science Translational Medicine.
The authors explained that the CytoPAN system is designed to address one of the biggest cancer challenges in low- and middle-income countries (LMICs), where more than two-thirds of cancer deaths occur: providing rapid, affordable diagnostics that enable patients to obtain locally available treatments.
Unfortunately, because of bottlenecks in specimen acquisition, complex handling logistics, a lack of pathologists, and limited laboratory infrastructure, diagnosis in many LMICs frequently takes months. Cancers typically are not diagnosed until advanced symptoms such as palpable mass lesions, weight loss, and malaise have become manifest.
Lesion assessment guides management
For women with suspicion of breast cancer, the authors noted, preoperative assessment of focal lesions for receptor status, presence of invasion, histologic type, and tumor grade are crucial for planning therapeutic management. For physicians to provide, for example, tamoxifen, which is commonly available at low cost in LMICs, they must know a patients’ hormone receptor status.
While core and open surgical biopsies yield abundant tissue for embedding, sectioning, and staining for subsequent histopathological analysis, they entail lengthy work flow and call for expensive instrumentation and a trained workforce, the authors noted.
Fine needle aspirations (FNAs) can be performed by nonphysicians after minimal training with very low complication rates. The much smaller–gauge needles (20-25 gauge) used in FNAs are generally well tolerated, the authors added.
This is why CytoPAN was designed for use with specimens obtained via FNA of palpable mass lesions.
Self-contained design
The CytoPAN system was engineered as a self-contained, integrated cytometry platform enabling same-day diagnosis and treatment of breast lesions.
The system was designed to comply with the World Health Organization’s “ASSURED” criteria (affordable, sensitive, specific, user friendly, rapid and robust, equipment free, and deliverable to end users), and to be potentially operable by nonphysicians after brief training.
CytoPAN operators collect cells through minimally invasive FNAs and use lyophilized immunostaining kits with relevant antibodies (not requiring refrigeration). Operators perform imaging using the CytoPAN device, which is then subjected to an automated analysis algorithm with results displayed on a user interface.
CytoPAN classifies detected malignant cells according to four subtypes reflecting estrogen receptor (ER), progesterone receptor (PR), and HER2 status – luminal HER2-negative, luminal HER2-positive, HER2-positive, and triple-negative breast cancer. This is intended to facilitate informed treatment choices (e.g., a selective ER modulator, antiestrogen or aromatase inhibitor for ER/PR-positive patients; an anti-HER2 agent for HER2-positive patients).
The final diagnostic report from a given patient sample includes cancer cell population and molecular subtype distribution. The entire diagnostic procedure takes less than an hour. A repeat biopsy, should the sample be nondiagnostic, can be taken within an hour.