Congenital Beckers nevus overlying plexiform neurofibroma in neurofibromatosis type-1: more than a rare association

Chetana Peenya Ramanand; Aishwarya Balawat; Kanakpura Nanjundaswamy Shivaswamy; Tharayil Kunneth Sumathy

doi:10.18203/issn.2455-4529.IntJResDermatol20250439

Authors

Chetana Peenya Ramanand Department of Dermatology, MS Ramaiah Medical College, Bengaluru, Karnataka India https://orcid.org/0009-0002-5412-4183
Aishwarya Balawat Department of Dermatology, MS Ramaiah Medical College, Bengaluru, Karnataka India https://orcid.org/0009-0007-5257-921X
Kanakpura Nanjundaswamy Shivaswamy Department of Dermatology, MS Ramaiah Medical College, Bengaluru, Karnataka India https://orcid.org/0000-0002-6234-4031
Tharayil Kunneth Sumathy Department of Dermatology, MS Ramaiah Medical College, Bengaluru, Karnataka India https://orcid.org/0000-0002-2200-9394

DOI:

https://doi.org/10.18203/issn.2455-4529.IntJResDermatol20250439

Keywords:

Plexiform neurofibroma, Congenital Becker’s nevus, Neurofibromatosis-1, Congenital pigmented plaque, Congenital hairy plaque, Co-occurrence

Abstract

Plexiform neurofibroma (PFN) is the hallmark of Neurofibromatosis type 1 (NF-1), an autosomal dominant disorder caused by mutations in the neurofibromin gene.1 Becker's nevus (BN) is an acquired pigmentary disorder characterized by hyperpigmentation and hypertrichosis, presenting in adolescence.2 Here we present a 28-year-old male with a congenital hyperpigmented pigmented patch over his back which later on increased in size and developed excessive hair growth and subsequently swelling. The patient had no other swellings of neurofibroma but satisfied all the criteria of Type-1 Neurofibromatosis. Clinical, dermoscopic and histopathologic features confirmed the diagnosis of PFN with BN in NF-1. Two special stains including S-100 and Fontana Mason stain ruled out other possibilities and further confirmed the diagnosis of Congenital Becker’s Nevus with Plexiform Neurofibroma in NF-1. The report emphasizes that in NF-1, Becker’s nevus can masquerade an ominous presence of plexiform neurofibroma. The case has been reported for the rarity of association of Congenital Beckers Nevus with Plexiform Neurofibroma in NF-1.

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References

Kresak JL, Walsh M. Neurofibromatosis: A review of NF1, NF2, and Schwannomatosis. J Pediatr Genet. 2016;5(2):98-104. DOI: https://doi.org/10.1055/s-0036-1579766

Alfadley A, Hainau B, AI Robaee A, Banka N. Becker’s Melanosis: a report of 12 cases with atypical presentation. Int J Dermatol. 2005;44:20-4. DOI: https://doi.org/10.1111/j.1365-4632.2004.02077.x

Sabitini C, Milani D, Menni F, et al. Treatment of neurofibromatosis type 1 Curr Treat Options Neurol. 2015;17:355. DOI: https://doi.org/10.1007/s11940-015-0355-4

Deuri D, Hulmani M. "The Black Hairy Bag of Worms Feel!": A Rare Association of Plexiform Neurofibroma with Overlying Becker's Nevus - Was it a Coincidence? Indian J Dermatol. 2023;68(5):579-581 DOI: https://doi.org/10.4103/ijd.ijd_47_23

Choi J, An S, Lim SY. Current concepts of neurofibromatosis type 1: pathophysiology and treatment. Arch Craniofac Surg. 2022;23(1):6-16 DOI: https://doi.org/10.7181/acfs.2022.00633

De Schepper S, Boucneau J, Lambert J, Messiaen L, Naeyaert JM. Pigment cell-related manifestations in neurofibromatosis type 1: an overview. Pigment Cell Res. 2005;18(1):13-24. DOI: https://doi.org/10.1111/j.1600-0749.2004.00206.x

Singh S, Khandpur S, Rai M, Ali F. Giant congenital Becker's nevus overlying a plexiform neurofibroma: Merely a coincidence or more than it? Indian J Dermatol Venereol Leprol. 2018;84:97-100 DOI: https://doi.org/10.4103/ijdvl.IJDVL_272_17

FV, Birlea S, Bosenberg MW, Brash D, Cassidy PB, Chen S, et al. Frontiers in pigment cell and melanoma research. Pigment Cell Melanoma Res. 2018;31(6):728–35. DOI: https://doi.org/10.1111/pcmr.12728

Kemkemer, R, Schrank, S, Vogel, W, Gruler, H., Kaufmann, D. Increased noise as an effect of haploinsufficiency of the tumor-suppressor gene neurofibromatosis type 1 in vitro. Proc Nat Acad Sci. 2002;99:13783-8. DOI: https://doi.org/10.1073/pnas.212386999

Choudhary SV, Dhope AA, Singh R, Tidke P. Plexiform Neurofibroma Overlying Giant Café-au-lait Macule. Indian Dermatol Online J. 2017;8(2):159-60. DOI: https://doi.org/10.4103/2229-5178.202270

Vathulya M, Hazarika N, Bhatia R, Praveen AJ. Pigmentation in Plexiform Neurofibroma Following Blaschko's Lines: A New Observation. J Cutan Aesthet Surg. 2021;14(3):381-3. DOI: https://doi.org/10.4103/JCAS.JCAS_148_20

KarlStaser, Feng-Chun Yang, D Wade Clapp. Pathogenesis of Plexiform Neurofibroma: Tumor-Stromal/Hematopoietic Interactions in Tumor Progression. Annu Rev Pathol. 2012;7:469-85. DOI: https://doi.org/10.1146/annurev-pathol-011811-132441

Adya KA, Inamadar AC, Palit A. Dermoscopic Pigment Network: Characteristics in Non-Melanocytic Disorders. Indian Dermatol Online J. 2020;11(2):146-53. DOI: https://doi.org/10.4103/idoj.IDOJ_246_19

Chauhan P, Bhardwaj N, Jindal R, Shirazi N. Dermoscopic findings of a congenital smooth muscle hamartoma in an infant. Pediatr Dermatol. 2020;37(1):251-3. DOI: https://doi.org/10.1111/pde.14072

Agrawal A, Bhardwaj A, Rao M. "Chicken-Wire Mesh" Pattern on Dermoscopy of Plexiform Neurofibroma. Indian Dermatol Online J. 2023;15(1):183-4. DOI: https://doi.org/10.4103/idoj.idoj_253_23

Elder DE, Elenitsas R, Rosenbach M, Murphy GF,Xiaowei Xu. Benign pigmented lesions and Malignant Melanoma. Rubin AI, Xu X, editors. Lever’s histopathology of the skin. 11th ed. Philadelphia: Wolters Kluwer; 2015;6:706-10.

Schaffer JV, Khachemoune A, Bolognia JL, McNiff JM, Nehal KS. Pigmented plexiform neurofibroma: distinction from a large congenital melanocytic nevus. J Am Acad Dermatol. 2007;56(5):862-8. DOI: https://doi.org/10.1016/j.jaad.2006.11.022