PRAME Expression in Mucosal Melanoma of the Head and Neck Region

Abstract

PRAME (PReferentially expressed Antigen in MElanoma), a cancer-testis antigen expressed in normal and neoplastic tissues with several functions, proved to be a useful diagnostic tool in the differential diagnosis between benign and malignant melanocytic lesions. The current study aims to perform PRAME stain on a retrospective case series of mucosal melanocytic tumors of the head and neck region to compare 3 different scores and evaluate the most reliable one in this diagnostic set. Immunohistochemical analysis for PRAME was performed in 54 benign and malignant mucosal melanocytic tumors of the head and neck region collected from 41 patients. The best-performing cutoff of PRAME-positive cells (nuclear stain) to differentiate benign and malignant mucosal melanocytic tumors of the head and neck region is that proposed by Raghavan and colleagues (< 60%/ ≥ 60% of PRAME-positive cells), with 100% and 77.8% of benign lesions and malignant tumors respectively correctly identified. Applying this score, PRAME stain showed the best results (sensitivity, specificity, accuracy, and positive and negative predictive values) for the diagnosis of head and neck melanocytic tumors. However, a subset of PRAME-negative malignant tumors was identified, especially located in the palatal area (hard and soft palate). Finally, high PRAME expression ( ≥ 60%) was associated with specific sites (nasal cavity/nasal septum/turbinates nasopharynx, and the maxillary sinus), nodular histotype, and female sex.

Penile melanoma: a pathological report of two cases

“…In a recent study, 98.1% of all nevi tested lacked PRAME expression, while six nevi showed a focal positivity [ 7 ]. Also, in another study, Ricci and his colleagues found that head and neck mucosal melanomas are characterized by PRAME expression [ 8 ]. In addition, they observed that high PRAME expression was associated with nodular histotype and interestingly, female gender.…”

PRAME Updated: Diagnostic, Prognostic, and Therapeutic Role in Skin Cancer

“…In conclusion, PRAME is more commonly expressed in malignant mucosal melanocytic lesions and its increased expression is associated with a poor prognosis. This factor appears to be a prognostic indicator independent of other factors, such as NRAS mutations, and its expression does not appear to correlate with the specific location of a malignant mucosal lesion [34,38,39]. PRAME expression is highly sensitive and specific in the context of acral melanomas and is a more predictive diagnostic tool than p16 immunohistochemistry.…”

“…A study by Ricci et al found that most benign melanocytic lesions of the mucosa of the head and neck do not show positive immunostaining for PRAME. However, a minority of cases show rare positive cells scattered in the lesion without significant changes in the expression intensity or location [38]. On the other hand, a study by Toyama et al reported that most mucosal melanomas express PRAME and a high PRAME expression correlates with a poor prognosis.…”

Expression of Preferentially Expressed Antigen in Melanoma, a Cancer/Testis Antigen, in Carcinoma In Situ of the Urinary Tract

“…Recently, PRAME expression has received much attention in some types of malignant tumor as a useful diagnostic marker due to its nature of being a cancer/testis antigen [13]. Notably, malignant melanoma and its mimics represents the most intensively investigated area of PRAME expression [14][15][16][17][18][19][20][21][22][23][24]. Numerous articles have examined the expression profiles of PRAME in malignant melanoma and have demonstrated its diagnostic utility.…”

“…Numerous articles have examined the expression profiles of PRAME in malignant melanoma and have demonstrated its diagnostic utility. Specifically, most cases of malignant melanoma exhibited positive immunoreactivity to PRAME; in contrast, most benign melanocytic nevi did not [14][15][16][17][18][19][20][21][22][23][24]. Moreover, PRAME expression has also been reported in various types of malignant tumor, other than malignant melanoma, including myxoid liposarcoma, synovial sarcoma, neuroblastoma, renal cell carcinoma, non-small-cell lung cancer, and thymic cancer [8,13,14,[25][26][27][28][29][30].…”