. Author manuscript; available in PMC: 2019 Jul 16.

Published in final edited form as: Am J Surg Pathol. 2018 Nov;42(11):1456–1465. doi: 10.1097/PAS.0000000000001134

TABLE 1.

Primary Cutaneous Melanomas With Diffuse (4+) PRAME IHC Expression

Melanoma Type	In Situ Only	Invasive	Total
Superficial spreading	12/12	37/41	49/53
Lentigo maligna	24/27	15/17	39/44
Acral	7/7	10/11	17/18
Nodular	NA	9/10	9/10
Other^*	2/2	6/8	8/10
Subtotal^†	45/48	77/87	122/135
Desmoplastic^‡	NA	7/20	7/20
Total	45/48	84/107	129/155

This category includes (proportion of cases with 4+ PRAME): lentiginous vulvar in situ melanomas (2/2), nevoid melanoma (2/2), malignant melanoma exblue nevus (0/1), cutaneous paramucosal (3/3), and unclassified invasive melanomas (1/2).

^†

Subtotal = all melanomas except for desmoplastic melanomas.

^‡

This category comprises (proportion of cases with 4+ PRAME): spindle cell melanomas with variable desmoplasia, including pure (0/4) and mixed (6/14) desmoplastic melanomas, and spindle cell neurotropic (1/2) melanomas.

NA indicates not available.