10.5826/dpc.1201a26
text/xml
2160-9381
1778
en
Hadir Shakshouk
https://creativecommons.org/licenses/by-nc/4.0
Dermatology Practical & Conceptual
case report
Trichofolliculoma Mimicking Squamous Cell Carcinoma 
Text.Serial.Journal
https://dpcj.org/index.php/dpc
Research Letter
2022-02-02
2021-05-06
2022-02-02
2022-02-09
e2022026
Dermatol Pract Concept
Hadir Shakshouk
2022/02/02
10.5826/dpc.1201a26
e2022026
Department of Dermatology, Andrology and Venerology, Alexandria University, Egypt
2160-9381
case report
en
e2022026
Garcia-Garcia SC, Villarreal-Martinez A, Guerrero-Gonzalez GA, Miranda-Maldonado I, Ocampo-Candiani J. Dermoscopy of trichofolliculoma: a rare hair follicle hamartoma. J Eur Acad Dermatology Venereol. 2017;31(2):e123-e124. DOI: 10.1111/jdv.13870. PMID: 27504964.
Trichofolliculoma Mimicking Squamous Cell Carcinoma 
https://dpcj.org/index.php/dpc/article/download/1778/1472
                   Dermatology Practical & Conceptual


           Trichofolliculoma Mimicking Squamous Cell
                           Carcinoma
                                         Ahmed Abdelbary1, Hadir Shakshouk1


1 Department of Dermatology, Andrology and Venerology, Alexandria University, Egypt



Key words: trichofolliculoma, adnexal tumors, hamartoma, dermoscopy, case report
Citation: Abdelbary A, Shakshouk H. Trichofolliculoma mimicking squamous cell carcinoma.
Dermatol Pract Concept. 2022;12(1):e2022026. DOI: https://doi.org/10.5826/dpc.1201a26
Accepted: June 6, 2021; Published: January 2022
Copyright: ©2022 Abdelbary and Shakshouk. 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: Both authors have contributed significantly to this publication.
Corresponding author: Hadir Shakshouk, MBBS, MSc, Department of Dermatology, Andrology and Venerology, Alexandria University,
Egypt. E-mail: drhadir58@gmail.com




Introduction                                                                   These features were highly suggestive of squamous cell
                                                                        carcinoma. However, histopathological examination demon-
Trichofolliculoma, a rare follicular hamartoma, manifests it-           strated multiple cystically dilated follicular infundibula lined
self as a solitary papule or nodule in adults involving the head        by stratified squamous epithelium with numerous vellus hair
and neck region. It is characterized by a single primary cystic         follicles originating from them. Multiple lobules of follicles of
structure from which radiates numerous secondary hair folli-            varying maturity were observed radiating from these dilated
cles. While dermoscopy has been widely used as a diagnostic             follicular infundibula. Some showed sebaceous glands. A fibro-
tool, dermoscopic features of adnexal lesions are poorly de-            cellular stroma surrounding the tumor was noted (Figure 1C).
scribed owing to their rarity and inadequate reporting.                 Thus, a diagnosis of trichofolliculoma was made.
                                                                               Written informed consent for publication of clinical de-
                                                                        tails and clinical images was obtained from the patient.
Case Presentation
We describe a 75-year-old male patient who presented with
                                                                        Conclusions
asymptomatic solitary nodule on the forehead of 2-years du-
ration. Upon examination, a single nodule of 1 cm diameter              Trichofolliculoma is considered to be a rare follicular ham-
with central crust and raised border was noted on his fore-             artoma that classically manifests as a papule or nodule
head (Figure 1A). Dermoscopic evaluation revealed a nodule              with a central dilated pore and tufted hairs. This presen-
with central crusting, multiple fine linear vessels, and whitish        tation corresponds histopathologically to a central primary
circles mainly on the margin (Figure 1B).                               follicle with many radiating secondary vellus hair follicles.




Research Letter | Dermatol Pract Concept. 2022;12(1):e2022026                                                                          1
                                                  Figure 1. (A) Clinical examination showed a well-defined nodule with central crust
                                                  on the forehead. (B) Dermoscopic evaluation showed a nodule with central crusting,
                                                  multiple fine linear vessels, and whitish circles mainly on the margin. (C) Histopatho-
                                                  logic examination showed dilated primary follicular infundibula with numerous sec-
                                                  ondary hair follicles, and a few showed sebaceous glands. A fibrocellular stroma
                                                  surrounding the tumor was noted (H&E, original magnification ×20).




While thought to be diagnostic for trichofolliculoma, few          stages, thickened primary follicle with fewer secondary folli-
cases demonstrate central hair tufting. The lack of a cen-         cles could be seen [2].
tral hair plug, as in our case, renders the clinical diagnosis         Trichofolliculoma classically presents with a hair plug
challenging.                                                       emanating from the center of a nodule; however, hair plug
    Dermoscopy of trichofolliculoma is not well described in       may be absent in many cases, making the diagnosis challeng-
literature. Panasiti et al reported a patient with single nod-     ing. In these cases, other serious diagnoses should be ruled
ule suspicious for basal cell carcinoma [1]. However, der-         out. Dermoscopy of trichofolliculoma is poorly described in
moscopic examination revealed a central brown zone with            the literature. We introduce the possibility of new dermo-
radial brown projections without pigment network, which            scopic findings of trichofolliculoma.
was described by the authors as a “firework” pattern. These
projections correlated histopathologically with the nests of
                                                                   References
cells radiating from a follicular epithelium [1]. Garcia-Gar-
cia and colleagues described different dermoscopic features         1. Panasiti V, Roberti V, Lieto P, Visconti B, Calvieri S, Perrella E. The
that included a well-defined bluish nodule with a white-               “firework” pattern in dermoscopy. Int J Dermatol. 2013;52(9):1158-
                                                                       1159. DOI: 10.1111/j.1365-4632.2011.05122.x. PMID: 22591242.
pink central area, shiny white structures, dotted vessels, and
                                                                    2. Garcia-Garcia SC, Villarreal-Martinez A, Guerrero-Gonzalez
a central scale in one patient [2]. Histopathologically, the
                                                                       GA, Miranda-Maldonado I, Ocampo-Candiani J. Dermoscopy
early stages demonstrated few secondary vellus hair follicles          of trichofolliculoma: a rare hair follicle hamartoma. J Eur Acad
originating from a primary follicle, whereas mature lesions            Dermatology Venereol. 2017;31(2):e123-e124. DOI: 10.1111/
showed increased number of vellus hair follicles. In later             jdv.13870. PMID: 27504964.



2                                                                      Research Letter | Dermatol Pract Concept. 2022;12(1):e2022026
