17 Jul 2025
University of Massachusetts Boston combines optical diagnostics and photodynamic therapy.
A project group including the University of Massachusetts Boston (UMass Boston) and Massachusetts General Hospital (MGH) has developed a new handheld intraoral device to detect and treat early stage oral cancer.
Described in Biophotonics Discovery, the device could significantly improve care and treatment regimes in low-resource settings.
“Oral squamous cell carcinoma (OSCC) is exceedingly prevalent and deadly in South Asia, especially the Indian subcontinent, affecting 15 out of every 100,000 people and claiming over 70,000 lives annually,” noted the project in its paper.
“This problem is compounded by inadequate medical infrastructure for screening and cancer care, especially in rural areas. These factors point to the need for new technology that enables timely diagnosis and point-of-care treatment of oral lesions, which can be accessible to medically underserved populations worldwide.”
The team’s solution is a compact, affordable device that can both image suspicious lesions and deliver light-based therapy to treat them. It builds on the group’s previous development of oral diagnostic devices employing autofluorescence (AF), polarized white light (pWL) imaging and machine learning to screen for suspicious oral lesions.
A previous implementation of this approach used a smartphone-attached ring of violet excitation LEDs surrounding an emission filter mounted over the phone camera, a configuration recognized by the project as not the most practical form factor for use in the field.
The new breakthrough integrates those capabilities into a single handheld device with a dental camera form factor, providing photodynamic therapy light delivery and multimodal imaging for diagnostics and monitoring.
Two separate technologies combined to streamline care
In its new architecture the device holds three light sources: a blue/violet LED emitting at 405 nanometers, a white LED at 450 to 650 nanometers and a diode laser outputting 630 nanometers. The white source enables polarized white light imaging, while the blue/violet LED is used for autofluorescence imaging via fluorescence excitation.
The diode laser is present to perform image-guided photodynamic therapy via the activation of a light-sensitive compound called protoporphyrin IX (PpIX), introduced during prior drug treatment and which accumulates in the patient’s cancer cells. Therapy with PpIX has shown promise in treating early oral cancers with minimal side effects.
In initial trials using simulated 3D oral tissues embedded with cancer cells, the system successfully imaged PpIX fluorescence up to 2.5 millimeters deep and showed effective photobleaching at depths relevant to early-stage oral cancers. Subsequent testing on mice showed that tumors treated with the device shrank significantly compared to untreated controls. Histological analysis revealed tumor cell death extending up to 3.5 millimeters deep.
By measuring the decrease in PpIX fluorescence during light exposure the system provides feedback on how much therapeutic dose has been delivered, a potential route to monitoring therapy in real time and ensuring that treatment is effective, even in settings without advanced medical infrastructure.
The project also used ratiometric imaging, comparing red and green fluorescence signals to improve the accuracy of lesion detection and treatment monitoring. This helps distinguish cancerous tissue from surrounding healthy areas, even in complex tissue environments.
“The study demonstrates that a low-cost, portable device can perform both diagnosis and treatment of early oral cancer,” commented the project. “By combining imaging and therapy in a single tool, the technology could streamline care in regions where access to specialists is limited.”