BRAF mutated and morphologically spitzoid tumors, a subgroup of melanocytic neoplasms difficult to distinguish from true Spitz neoplasms Journal Article
| Authors: | Gerami, P.; Chen, A.; Sharma, N.; Patel, P.; Hagstrom, M.; Kancherla, P.; Geraminejad, T.; Olivares, S.; Biswas, A.; Bosenberg, M.; Busam, K. J.; de La Fouchardière, A.; Duncan, L. M.; Elder, D. E.; Ko, J.; Landman, G.; Lazar, A. J.; Lowe, L.; Massi, D.; Mihic-Probst, D.; Parker, D. C.; Scolyer, R. A.; Shea, C. R.; Zembowicz, A.; Yun, S. J.; Blokx, W. A. M.; Barnhill, R. L. |
| Article Title: | BRAF mutated and morphologically spitzoid tumors, a subgroup of melanocytic neoplasms difficult to distinguish from true Spitz neoplasms |
| Abstract: | Drivers of Spitz neoplasms include activating point mutations in HRAS and Spitz-Associated genomic fusions. It has become evident that some BRAF-mutated melanocytic neoplasms can morphologically mimic Spitz tumors (STs). These have been termed BRAF mutated and morphologically spitzoid (BAMS). In this study, 17 experts from the International Melanoma Pathology Study Group assessed 54 cases which included 40 BAMS and 14 true STs. The participants reviewed the cases blinded to the genomic data and selected among several diagnostic options, including BAMS, ST, melanoma, and other. A total of 38% of all diagnostic selections in the BAMS cases were for BAMS, whereas 32% were for ST. In 22 of the BAMS cases, the favored diagnosis was BAMS, whereas in 17 of the BAMS cases, the favored diagnosis was ST. Among the 20 cases in the total group of 54 with the highest number of votes for ST, half were BAMS. Of BAMS, 75% had a number of votes for ST that was within the SD of votes for ST seen among true ST cases. There was poor interobserver agreement for the precise diagnosis of the BAMS (kappa = 0.16) but good agreement that these cases were not melanoma (kappa = 0.7). BAMS nevi/tumors can closely mimic Spitz neoplasms. Expert melanoma pathologists in this study favored a diagnosis of ST in nearly half of the BAMS cases. There are BAMS cases that even experts cannot morphologically distinguish from true Spitz neoplasms. © 2024 Wolters Kluwer Health. All rights reserved. |
| Keywords: | immunohistochemistry; adolescent; adult; child; controlled study; human tissue; major clinical study; genetics; tumor localization; melanoma; nevus; skin neoplasms; diagnosis, differential; differential diagnosis; pathology; histology; morphology; skin tumor; fluorescence in situ hybridization; dna; messenger rna; genomics; spitz nevus; nevus, epithelioid and spindle cell; dysplastic nevus; point mutation; b raf kinase; pathologist; braf; tumor diagnosis; proto-oncogene proteins b-raf; braf protein, human; epidermis hyperplasia; anaplastic lymphoma kinase; dysplastic nevi; spitz nevi; interrater reliability; dysplastic nevus syndrome; melanocytic tumor; atypical spitz tumors; spitzoid melanoma; humans; human; male; female; article; atypical spitz nevus; spitz melanoma; spitzoid lesions |
| Journal Title: | American Journal of Surgical Pathology |
| Volume: | 48 |
| Issue: | 5 |
| ISSN: | 0147-5185 |
| Publisher: | Lippincott Williams & Wilkins |
| Date Published: | 2024-05-01 |
| Start Page: | 538 |
| End Page: | 545 |
| Language: | English |
| DOI: | 10.1097/pas.0000000000002194 |
| PUBMED: | 38525831 |
| PROVIDER: | scopus |
| DOI/URL: | |
| Notes: | Article -- Source: Scopus |
