Pump-probe imaging differentiates melanoma from melanocytic nevi

Area of Science:

• Dermatology
• Biophysics
• Medical Imaging

Background:

• Melanoma diagnosis faces challenges with variable accuracy in visual inspection and biopsy interpretation.
• Distinguishing malignant melanoma from benign nevi is clinically significant yet difficult.

Purpose of the Study:

• To develop and evaluate a multiphoton imaging technique for accurate melanoma diagnosis.
• To differentiate between malignant melanoma and nonmalignant nevi based on melanin content and tissue architecture.

Main Methods:

• Utilized pump-probe spectroscopy-based multiphoton imaging to analyze eumelanin and pheomelanin distribution in skin lesions.
• Examined 42 pigmented skin lesion slices, assessing melanin ratios and cytological/architectural features.
• Adapted the technique for use with hematoxylin and eosin (H&E)-stained slides.

Main Results:

• Melanomas showed increased eumelanin content compared to nonmalignant nevi.
• The eumelanin to pheomelanin ratio identified all melanomas while excluding most dysplastic and benign nevi.
• Multiphoton imaging of architectural features improved specificity, reducing false positives.

Conclusions:

• Multiphoton imaging offers a sensitive and specific method for melanoma diagnosis by quantifying melanin chemistry and tissue structure.
• Integrating melanin chemical contrast into H&E staining can aid pathologists in improving melanoma diagnostic accuracy.