Dermatology: Practical and Conceptual Research Letter | Dermatol Pract Concept. 2022;12(2):e2022064 1 Cutaneous Involvement of Mantle Cell Lymphoma: Report of Two Cases with Dermatoscopic Features Bengü Nisa Akay1, Banu Farabi2, Mehmet Fatih Atak1, Isinsu Kuzu3, Aylin Okcu Heper3 1 Department of Dermatology, Ankara University, Ankara, Turkey 2 Department of Internal Medicine, Saint Peter’s University Hospital, New Brunswick, New Jersey, USA 3 Department of Pathology, Ankara University, Ankara, Turkey Key words: mantle cell lymphoma, dermatoscopy, dermoscopy, prognosis, serpentine vessels Citation: Akay BN, Farabi B, Atak MF, Kuzu I, Heper AO. Cutaneous Involvement of Mantle Cell Lymphoma: Report of Two Cases with Dermatoscopic Features. Dermatol Pract Concept. 2022;12(2):e2022064. DOI: https://doi.org/10.5826/dpc.1202a64 Accepted: September 6, 2021; Published: April 2022 Copyright: ©2022 Akay 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, MD, PGY-1, Department of Medicine, Saint Peter’s University Hospital-Rutgers Robert Wood Johnson Medical School, 4th Floor CARES, 240 Easton Avenue, New Brunswick, NJ 08901. E-mail: banufarabi91@gmail.com Introduction Mantle cell lymphoma (MCL) is a rare aggressive B-cell lym- phoma and represents 6% of all non-Hodgkin lymphomas. Cutaneous involvement (CI) of systemic MCL is rarely re- ported and is related to poor prognosis. Skin involvement in systemic lymphomas (SLs) can be challenging. Dermatos- copy may serve as a useful tool to diagnose and ameliorate the prognosis by leading early diagnosis. In this context, we present two cases of MCL with secondary CI, who presented with widespread plaques and nodules and describe their der- matoscopic features. Case Presentations The first patient was a 73-year-old male diagnosed with MCL in 2014. He referred to dermatology department for asymptomatic pink-red colored generalized skin lesions in August 2018 (Figure 1A). Dermatoscopic examination showed pink white structureless lesions with unfocused thick serpentine vessels (Figure 1B). Second patient was a 66-year-old female diagnosed with MCL in 2017, admit- ted for multiple nodular lesions developed on the trunk and extremities in January 2019 (Figure 1C). Dermato- scopic examination showed thick serpentine-branched and reticular vessels on whitish-pink violaceous background (Figure 1D). Both lesions were biopsied and showed sim- ilar features including diffuse infiltration of the mid and deeper dermis with medium-sized lymphocytes with irreg- ular nuclei. The tumor cells were positive for CD5, CD20, CD79a, cyclin D1, and negative for CD10 (Figure 2). Both patients were diagnosed with CI of MCL. They have been treated with combined chemotherapy regimens including rituximab, unfortunately both patients were deceased due to disease dissemination (14 months and 18 months after CI, respectively). 2 Research Letter | Dermatol Pract Concept. 2022;12(2):e2022064 Discussion MCL originates from primarily lymph nodes and extra-nodal organs (bone marrow, spleen, gastrointestinal tract). Skin in- volvement portends a poor prognosis and is seen in 2% of the cases. Previously, 24 cases of secondary CI of MCL have been reported. The value of dermatoscopic examination in cutaneous lym- phomas (CL) have been proposed in previously published stud- ies. A recent systematic review regarding dermatoscopic findings in primary CLs showed that dermatoscopy assisted skin biop- sies ensure early diagnosis based on the findings such as salm- on-colored background, fine short/linear irregular serpentine vessels, scale, and white areas/circles [1]. Regarding the derma- toscopic features of secondary CI of SLs, only 1 case of MCL has been reported and showed multiple chaotically distributed short linear vessels with multiple red dots within hair follicles on a whitish background. As the lesion progressed, wider telan- giectatic vessels on a reddish background were observed, and the lesions regressed under treatment [2]. We observed pink and white structureless lesions with unfocused thick short serpen- tine vessels in flat lesions, as lesions became nodular as in our second patient, the vessel calibers increased, branched and re- ticular vessels were observed on purple-pink, white background which is hypothetically due to increased tumor volume and ex- pansion of the dermis by malignant infiltrate. Conclusions Skin involvement in MCL suggests poor prognosis. Though, dermatoscopic features are not specific to CI of SLs, they can raise suspicion to biopsy these lesions in earliest stages. Figure 1. (A,B) Clinical and dermatoscopic pictures of case 1. (A) Multiple erythematous indurated papules and plaques on the fore- head. (B) The dermatoscopic image shows pink and white structureless lesions with unfocused thick short serpentine vessels. (C,D) Clinical and dermatoscopic photos of case 2. (C) Multiple, purple-colored nodular lesions on the right anterior leg. (D) the dermato- scopic image shows thick vessels, branched, and reticular vessels on purple, pink and white background. Research Letter | Dermatol Pract Concept. 2022;12(2):e2022064 3 References 1. Sławińska M, Sokołowska-Wojdyło M, Olszewska B, Nowicki RJ, Sobjanek M, Zalaudek I. Dermoscopic and trichoscopic features of primary cutaneous lymphomas - systematic review. J Eur Acad Dermatol Venereol. 2021;35(7):1470-1484. DOI: 10.1111/jdv.17219. PMID: 33710688. 2. Swoboda R, Kaminska-Winciorek G, Jaworska M, Giebel S. Dermoscopic follow-up of therapeutic response in mantle cell lymphoma with secondary involvement of the scalp. J Cosmet Dermatol. 2018 Dec 5. DOI: 10.1111/jocd.12826. Epub ahead of print. PMID: 30520227. Figure 2. Histological and immunohistochemical findings of the papules from case 2. (A) Diffuse proliferation of small atypical lymphoid cells with fine chromatin (H&Ex10). The subcutaneous atypical lymphoid cells were expressing strong CD20 (b) and CD5 (c) , pale IgD(d). (E,F) The cells were specifically negative for CD3 (e) and positive for cyclin D (f).