Related Experiment Video
Updated: Aug 1, 2025
A Robust Discovery Platform for the Identification of Novel Mediators of Melanoma Metastasis
Published on: March 8, 2022
Potential diagnostic utility of PRAME and p16 immunohistochemistry in melanocytic nevi and malignant melanoma
Hisham F Bahmad1, Kei Shing Oh1, John Alexis1,2
1The Arkadi M. Rywlin M.D. Department of Pathology and Laboratory Medicine, Mount Sinai Medical Center, Miami Beach, Florida, USA.
Background:
PRAME (PReferentially expressed Antigen in MElanoma) is a tumor-associated antigen that has been studied in various cutaneous melanocytic lesions. p16, on the other hand, has been proposed to aid in distinguishing between benign and malignant melanocytic neoplasms. Studies on the diagnostic utility of PRAME and p16 in combination in differentiating nevi from melanoma are limited. We aimed to assess the diagnostic utility of PRAME and p16 in melanocytic tumors and their role in distinguishing between malignant melanomas and melanocytic nevi.
Methods:
This is a single-center retrospective cohort analysis over a 4-year period (2017-2020). We used the pathological database of malignant melanomas (77 cases) and melanocytic nevi (51 cases) specimens from patients who underwent shave/punch biopsies or surgical excisions and evaluated immunohistochemical staining percentage positivity and intensity for PRAME and p16.
Results:
Most malignant melanomas showed positive/diffuse PRAME expression (89.6%); on the other hand, 96.1% of nevi did not express PRAME diffusely. p16 was expressed consistently in nevi (98.0%). However, p16 expression in malignant melanoma was infrequent in our study. PRAME had a sensitivity and specificity of 89.6% and 96.1%, respectively, for melanomas versus nevi; on the other hand, p16 had a sensitivity and specificity of 98.0% and 28.6%, respectively, for nevi versus melanoma. Also, a PRAME+/p16- melanocytic lesion is unlikely to be a nevus where most nevi were PRAME-/p16+.
Conclusion:
In conclusion, we confirm the potential utility of PRAME and p16 for distinguishing melanocytic nevi from malignant melanomas.
Insights
PRAME and p16 are useful biomarkers for differentiating melanocytic nevi from malignant melanomas. Most melanomas express PRAME, while most nevi express p16, aiding in diagnosis.
Area of Science:
- Dermatopathology
- Oncology
- Immunohistochemistry
Background:
- PRAME (PReferentially expressed Antigen in MElanoma) is a tumor antigen in cutaneous lesions.
- p16 is a marker for distinguishing benign from malignant melanocytic neoplasms.
- Limited studies exist on the combined diagnostic utility of PRAME and p16.
Purpose of the Study:
- Assess the diagnostic utility of PRAME and p16 in melanocytic tumors.
- Evaluate their role in differentiating malignant melanomas from melanocytic nevi.
Main Methods:
- Retrospective cohort analysis of 77 malignant melanomas and 51 melanocytic nevi (2017-2020).
- Immunohistochemical staining for PRAME and p16 was evaluated for percentage positivity and intensity.
Main Results:
- Malignant melanomas showed high PRAME expression (89.6%), while nevi typically did not (96.1%).
- Nevi showed consistent p16 expression (98.0%), whereas malignant melanoma expression was infrequent.
- PRAME demonstrated 89.6% sensitivity and 96.1% specificity for melanoma; p16 showed 98.0% sensitivity and 28.6% specificity for nevi.
Conclusions:
- PRAME and p16 show potential utility in distinguishing melanocytic nevi from malignant melanomas.
- A PRAME+/p16- profile suggests a lesion is unlikely to be a nevus.
