Every year in the US, 650,000 cancer patients are treated with chemotherapy. As a side effect, their neutrophil counts (number of white blood cells that aid in fighting infections) become low (referred to as neutropenia) and expose them to febrile neutropenia (FN) which are episodes of serious infection that entail costly hospitalization and sometimes death. If neutropenia is detected early, FN can be avoided through timely delivery of prophylactic antibiotics or growth stimulating factors. Currently, neutrophil measurements require visits to healthcare centers. This increases infection risk (as measurements are taken infrequently and low counts may not be detected before infections ensue) and reduces chemotherapy efficacy (as chemotherapy levels are kept at the lower end of frequency and dose for safety).
We aim to overcome this limitation with PointCheck, a noninvasive neutrophil test that can be used frequently in local health centers or at home, enabling physicians to minimize infections and personalize chemotherapy planning. The basis for our technology is noninvasive optical imaging of microcirculation in nailfold capillaries. We conducted a pilot clinical study where trained nurses used PointCheck to acquire data from 46 chemotherapy patients. By manually analyzing a training dataset (N=38 measurements from 16 patients), we built a labeled dataset of flow gaps in the microcirculation that can be considered proxies of neutrophils and demonstrated their number can be used to distinguish baseline patients (>500 neutrophils/mm3) from grade IV neutropenic ones (<500/mm3). However, the need for manual analysis makes the technology inaccessible to patients on its current status. With support from SBIR Phase I, we will (a) develop algorithms that automatize the manual data processing workflow employed on our training set, (b) test those algorithms on our acquired and unanalyzed testing database (N=103 measurements from 30 patients) and (c) generate additional performance data including further intermediate neutrophil ranges (>500 and <1,500 neutrophils/mm3), thus fulfilling the requirements for a minimum viable product. The consecution of these milestones will enable, in Phase II, using PointCheck in a multi-site diagnostic validation trial to confirm, under clinical conditions, that the management of FN can be improved with this new paradigm.
Development of a portable optical imaging device that can noninvasively detect neutropenia-related immunosuppression, to enable more frequent monitoring of chemotherapy patients so that timely medical interventions can be staged before life-threatening infections develop.
