Dermatology: Practical and Conceptual


Image Letter | Dermatol Pract Concept. 2023;13(3):e2023156 1

A Congenital Plaque-Like Myofibroblastic Tumor
Haifa Mkhinini1, Nadia Fetoui Ghariani1, Badreddine Sriha2, Mohamed Denguezli1

1 Dermatology Department, Faculty of Medicine of Sousse, Farhat Hached University Hospital, Sousse, Tunisia

2 Anatomopathology Department, Faculty of Medicine of Sousse, Farhat Hached University Hospital, Sousse, Tunisia

Citation: Mkhinini H, Fetoui Ghariani N, Sriha B, Denguezli M. A Congenital Plaque-Like Myofibroblastic Tumor. Dermatol Pract 
Concept. 2023;13(3):e2023156. DOI: https://doi.org/10.5826/dpc.1303a156

Accepted: January 4, 2023; Published: July 2023

Copyright: ©2023 Mkhinini et al. This is an open-access article distributed under the terms of the Creative Commons Attribution-
NonCommercial License (BY-NC-4.0), https://creativecommons.org/licenses/by-nc/4.0/, which permits unrestricted noncommercial use, 
distribution, and reproduction in any medium, provided the original authors and source are credited.

Funding: None.

Competing interests: None.

Authorship: All authors have contributed significantly to this publication.

Corresponding author: Haifa Mkhinini, Resident, Faculty of Medicine of Sousse Dermatology Department, Farhat Hached University 
Hospital, Sousse, Tunisia. E-mail: Haifa.mkhinini90@gmail.com

Case Presentation

A 6-month-old boy presented with a history of congenital 

plaque on the right peri axillary region. Physical examina-

tion revealed an irregular violaceous, infiltrated plaque with 

central fine scales, measuring 30mm x15 mm (Figure 1A). 

Dermoscopy showed structureless whitish and violaceous 

areas, some dotted vessels and a thin peripheral pigmented 

network (Figure 1B). Histopathological examination of a 

skin biopsy showed a proliferation of spindle cells extend-

ing throughout the reticular dermis, arranged in a storiform 

pattern and separated from the epidermis by a grenz zone. 

The superjacent epidermis was hyperplastic with hyperpig-

mentation of the basal layer (Figure 1, C and D). Immuno-

histochemistry demonstrated diffuse positivity for smooth 

muscle actin (Figure 1E) while immunostaining for CD34 

was negative. The diagnosis of plaque-like myofibroblastic 

tumor (PLMT) was made.

Teaching Point

PLMT is a rare, benign pediatric tumor, firstly described in 

2007. It occurs commonly in infants and young  children 

within the first 4 years of life [1]. This tumor typically presents 

as a slowly growing firm, red-brown colored, papulonodular 

plaque, mostly localized on the lower back [1]. Clinical dif-

ferential diagnosis includes giant dermatofibroma, multiple 

clustered dermatofibroma and dermatofibrosarcoma protu-

berans. Histopathological examination shows the same fea-

tures as dermatofibroma, but immunohistochemistry favors 

a myofibroblastic lineage [1]. Recurrence after surgical exci-

sion is reported [2].

References

1. Sekar T, Mushtaq J, AlBadry W, et al. Plaque-like Myofibro-

blastic Tumor: 2 Cases of This Unusual Dermal Tumor Which 

 Occurs in Infancy and Early Childhood. Pediatr Dev Pathol. 

2018;21(5):444-448. DOI: 10.1177/1093526617746807. PMID:  

29224420.

2. Moulonguet I, Biaggi A, Eschard C, et al. Plaque-Like Myofi-

broblastic Tumor: Report of 4 Cases. Am J Dermatopathol. 

2017;39(10):767-772. DOI: 10.1097/DAD.0000000000000869. 

PMID: 28930106.



2 Image Letter | Dermatol Pract Concept. 2023;13(3):e2023156

Figure 1. (A) Violaceous nodular plaque of the right peri axillary region. (B) Dermoscopy showed whitish and violaceous areas, peripheral 

pigmented network and dotted vessels. (C) Acanthosis, proliferation of spindle cells within the reticular dermis (H&E, ×200) arranged in a 

storiform pattern (D) (H&E, ×200). (E) Strong positivity for smooth muscle actin.