10.5826/dpc.1301a30
text/xml
2160-9381
2389
en
Manu Jain
https://creativecommons.org/licenses/by-nc/4.0
Dermatology Practical & Conceptual
dendritic cells
Identifying Pitfalls for Diagnosing Pigmented Bowen Disease on Reflectance Confocal Microscopy: Misleading Dendritic Cells
Text.Serial.Journal
https://dpcj.org/index.php/dpc
Research Letter
2023-01-31
2022-03-06
2023-01-31
2023-03-01
e2023030
Dermatol Pract Concept
Manu Jain
2023/01/31
10.5826/dpc.1301a30
e2023030
Department of Dermatology, Weil Cornell Medical School, NY, USA; Dermatology Department, Memorial Sloan Kettering Cancer Center
2160-9381
dendritic cells
en
e2023030
Karaarslan I, Tepret S, Yildiz S, Yaman B, Ozdemir F. The role of reflectance confocal microscopy in a case of Bowen's disease difficult to diagnose. Dermatol Pract Concept. 2018;8(1):63-65. DOI: 10.5826/dpc.0801a15. PMID: 29445580. PMCID: PMC5808377.
Identifying Pitfalls for Diagnosing Pigmented Bowen Disease on Reflectance Confocal Microscopy: Misleading Dendritic Cells
https://dpcj.org/index.php/dpc/article/download/2389/1912
         Identifying Pitfalls for Diagnosing Pigmented
            Bowen Disease on Reflectance Confocal
            Microscopy: Misleading Dendritic Cells
                                    Banu Farabi1,2,3, Babar K. Rao4, Manu Jain4,5


1 Department of Dermatology, New York Medical College, Valhalla, New York, NY, USA
2 Department of Dermatology, NYC Health + Hospitals/Metropolitan, New York, NY, USA
3 Department of Dermatology, NYC Health + Hospitals/Coney Island, Brooklyn, NY, USA
4 Department of Dermatology, Weil Cornell Medical School, NY, USA
5 Dermatology Department, Memorial Sloan Kettering Cancer Center, NY, USA



Key words: Bowen’s disease, squamous cell carcinoma in situ, reflectance confocal microscopy, dermatoscopy, dermoscopy, dendritic cells
Citation: Farabi B, Rao BK, Jain M. Identifying pitfalls for diagnosing Pigmented Bowen’s Disease on Reflectance Confocal Microscopy:
Misleading dendritic cells. Dermatol Pract Concept. 2023;13(1):e2023030. DOI: https://doi.org/10.5826/dpc.1301a30
Accepted: June 13, 2022; Published: January 2023
Copyright: ©2023 Farabi 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: Banu Farabi, 1901 First Avenue, New York, NY, 10029. Telephone: +1 (212) 423 7467, Fax: +1 (212) 423 8464,
Email: banufarabi91@gmail.com




Introduction                                                            Case Presentation
Pigmented Bowen disease (pBD) is a rare variant of squa-                A 73-year-old female with skin type II was seen for a 5 mm
mous cell carcinoma in situ of the skin. Precise diagnosis              pigmented lesion on the right cheek (Figure 1A). Derma-
of pBD can be difficult based only on clinical and derma-               toscopic examination showed an asymmetrical pigmented
toscopic findings. Reflectance confocal microscopy (RCM)                lesion with multiple colors, pigmented circles, and dotted
plays an important role by showing atypical keratinocytes               and fine linear vessels on an erythematous background
and full thickness atypia in vivo. Previous studies showed              (Figure 1B). RCM images at the spinous and supra-papillary/
confounding presence of hyper-refractile elongated den-                 basal layer showed an atypical honeycomb (Figure 1, C and D)
dritic cells in pigmented actinic keratosis (AK)/pBD on                 pattern and numerous bright edged papillae (Figure 1E)
RCM [1].                                                                and dispersed bright fusiform and stellate shaped cells with
   We present a case of pBD located on the facial skin mis-             thin dendrites (Figure 1F). A complete surgical excision of
diagnosed as lentigo maligna with RCM due to the presence               the lesion was performed with 2 mm of tumor-free mar-
of abundant hyper-refractile, atypical dendritic cells in the           gins. Histopathology revealed a pBD including full thickness
interfollicular spaces.                                                 keratinocytic atypia, prominent basal layer pigmentation,
                                                                        ­




Research Letter | Dermatol Pract Concept. 2023;13(1):e2023030                                                                             1
Figure 1. (A) Clinical examination of the lesion on the right preauricular area shows a 5 mm diameter asymmetrical pigmented. (B) Derma-
toscopy reveals an asymmetrical pigmented lesion with multiple colors, pigmented circles, dotted and fine linear vessels on an erythematous
background. (C) RCM images at the spinous and suprapapillary/basal layer shows an atypical honeycomb pattern and numerous bright
edged papillae. (D) Higher magnification of atypical honeycomb pattern adjacent to the lesion which is highlighted with red bracket in (C).
(E) Higher magnification of bright ringed-edged papillae at the level of dermo-epidermal junction shown with yellow arrow in (C). (F) Higher
magnification of dendritic cells between ringed edged papillae (this image is obtained with VivaStack mode).




                                      Figure 2. Histologic examination shows full thickness keratinocyte
                                      atypia, disorganization of the keratinocyte and prominent basal layer
                                      pigmentation with dermal melanophages.




and dermal melanophages (Figure 2). The patient continues               presents as atypical or disarranged honeycomb pattern. Re-
routine care via skin cancer surveillance.                              cent studies highlighted that intraepidermal dendritic cells
                                                                        can be found in pigmented AK/pBD which creates a poten-

Conclusions                                                             tial diagnostic pitfall. Moscarella et al reported dendritic
                                                                        cells in 12/17 cases of AK/BD [3]. Persechino et al found
The diagnosis of pBD can be challenging clinically due to               bright interfollicular dendritic cells in 53% of AK cases [4].
relative rarity and various clinical presentations. Dermatos-           RCM features of LM includes atypical melanocytes and nests
copy can be a helpful tool in diagnosing these lesions [2].             surrounding adnexal openings, sheets of cells composed of
However, in equivocal cases, RCM plays an important role                mainly dendritic cells giving a ‘medusa head’ appearance at
in differentiating pBD from lentigo maligna (LM). Typical               dermo-epidermal junction (DEJ). Folliculotropism is a typi-
RCM features of BD are full thickness keratinocytic atypia              cal feature of LM and is visualized as dendritic, atypical cells
and architectural disorganization of the epidermis which                infiltrate the follicles [4]. Thus, it is important to visualize

2                                                                           Research Letter | Dermatol Pract Concept. 2023;13(1):e2023030
DEJ in detail and follicular structures for signs of d
                                                     ­ endritic           cells. Skin Res Technol. 2017;23(1):126-128. DOI: 10.1111
cell infiltration to rule out LM. Other clues for pBD are nu-             /srt.12304. PMID: 27430726.
                                                                       2. Inskip M, Cameron A, Akay BN, et al. Dermatoscopic features of
merous marked small bright rings at DEJ [5,6]. Since DEJ
                                                                          pigmented intraepidermal carcinoma on the head and neck. J Dtsch
is infiltrated by malignant melanocytes in LM, presence of
                                                                          Dermatol Ges. 2020;18(9):969-976. doi: 10.1111/ddg.14220.
regularly shaped bright rims can signify pigmented AK/pBD.                PMID: 32841518.
    Intraepithelial hyper-reflective dendritic cells are found         3. Moscarella E, Rabinovitz H, Zalaudek I, et al. Dermoscopy
quite high in pBD. The exact nature of these cells is u
                                                      ­ nknown,           and reflectance confocal microscopy of pigmented actinic
and density of dendritic cells can correlate with clinical pig-           keratoses: a morphological study. J Eur Acad Dermatol Ve-
                                                                          nereol. 2015;29(2):307-314. DOI: 10.1111/jdv.12532. PMID:
mentation of the lesion. Thus, it is imperative to be aware of
                                                                          24754497.
the presence of dendritic cells. In the presence of dendritic
                                                                       4. Persechino F, De Carvalho N, Ciardo S, et al. Folliculotropism in
cells in a pigmented lesion should not prompt extensive sur-              pigmented facial macules: Differential diagnosis with reflectance
gical excision without the evidence of melanocytic neoplasm.              confocal microscopy. Exp Dermatol. 2018;27(3):227-232. DOI:
In doubt, incisional biopsy of the lesion should be considered            10.1111/exd.13487. PMID: 29274094.
to avoid extensive surgical treatment. Thus, RCM plays a               5. Mazzilli S, Gamo-Villegas R, Pampin-Franco A, et al. Reflec-
                                                                          tance Confocal Microscopy of Pigmented Bowen’s Disease: A
critical role for the management of facial pigmented lesions
                                                                          Case Series of Difficult to Diagnose Lesions. Case Rep D
                                                                                                                                 ­ ermatol.
in aesthetically sensitive sites.
                                                                          2020;12(2):98-106.DOI: 10.1159/000507916.PMID: 32518541.
                                                                          PMCID: PMC7265740.
                                                                       6. Karaarslan I, Tepret S, Yildiz S, Yaman B, Ozdemir F. The role
References                                                                of reflectance confocal microscopy in a case of Bowen’s dis-
                                                                          ease difficult to diagnose. Dermatol Pract Concept. 2018;8(1):
 1. Debarbieux S, Perrot JL, Cinotti E , et al. Reflectance confocal      63-65. DOI: 10.5826/dpc.0801a15. PMID: 29445580. P
                                                                                                                           ­ MCID:
    microscopy of Pigmented Bowen’s disease: misleading dendritic         PMC5808377.




Research Letter | Dermatol Pract Concept. 2023;13(1):e2023030                                                                            3
