H-Scan Discrimination for Tumor Microenvironmental Heterogeneity in Melanoma

Area of Science:

• Oncology
• Medical Imaging
• Immunology

Background:

• Melanoma exhibits significant tumor microenvironment (TME) heterogeneity due to genetic mutations, complicating treatment and leading to high mortality rates.
• Accurate, non-invasive methods are needed to discriminate TME heterogeneity for effective therapy selection in metastatic melanoma.

Purpose of the Study:

• To investigate the utility of ultrasound (US) radiofrequency data analysis for discriminating TME heterogeneity in murine melanoma models.
• To assess the capability of US features, including H-scan analysis, to differentiate between distinct melanoma lines and monitor responses to immunomodulatory therapies.

Main Methods:

• Utilized in vivo murine melanoma models (YUMM 1.7 and YUMMER 1.7) treated with immunomodulatory antibodies (anti-CD8, anti-PD-1).
• Longitudinal ultrasound scanning and processing of radiofrequency data using H-scan analysis, attenuation estimation, and B-mode processing to extract US features.
• Compared US features between different TMEs and treatment groups.

Main Results:

• A combined H-scan parameter significantly differentiated untreated YUMMER and YUMM melanoma models.
• H-scan analysis also resolved differences in YUMMER models treated with PD-1 inhibition or CD8 depletion.
• B-mode and attenuation measures were insufficient for differentiating melanoma lines or monitoring treatment responses, highlighting the importance of H-scan.

Conclusions:

• H-scan analysis demonstrates potential for discriminating heterogeneous melanoma metastases non-invasively.
• This approach may guide diagnosis and personalize treatment selection for melanoma.
• The findings suggest a reduced need for invasive biopsies or immunologic assessments in melanoma management.