On the peculiarities of seborrheic keratosis pigmentation

Cover Page

Cite item


Seborrheic keratosis (SK) is a common benign epithelial skin tumor that exists in a variety of clinical op - tions. The color of the tumor varies from yellow to dark brown, which leads to diagnostic errors. There is аlittle data about pigmentation of the SK in the literature. There is no consensus on the content of melanocytes in the SK.

Objective: to study the nature of the distribution of melanin in the SK and its relationship with the number of melanocytes.

Materials and methods. An analysis of 130 histological preparations with a verified diagnosis of SK and immunohistochemistry (IHC) test with monoclonal antibodies to Melan A (clone A103 ready-to-use) have been performed. Material sampling was performed in 130 patients with SK at the age of 46–77. In 48.5 % of the material was taken from places that are easily exposed to sunlight, 51.5 % — from places that are often closed, less prone to exposure to UV-radiation.

Results. As a result of histological examination, three types of pigmentation of the SK were identified, depending on the accumulation and location of pigment in the tumor. IHC test with monoclonal antibodies to Melan A in all cases of SK revealed a significant decrease in the content of melanocytes (0.7–5 %), compared with the unaffected epidermis (10.7–14.3 %) (р = 0.001). The greatest number of melanocytes (3–5 %) was recorded in SK, which were removed from places exposed to UV radiation.

Conclusions. A significant decrease in the content of melanocytes (less than 3 % of tumor cells) in the most pigmented SK (p = 0.0003), the lack of activation of melanogenesis in the tumor under the influence of UV radiation indicates the accumulation of pigment due to its slow utilization, due to aging and a de - crease in metabolismtumor cells.

About the authors

A. K. Alexandrova

I. M. Sechenov First Moscow State Medical Universit y, Ministry of Health of the Russian Federation

Author for correspondence.
Email: veter278@rambler.ru
ORCID iD: 0000-0001-9166-9807

Alexandra K. Alexandrova* — Cand. Sci. (Med.), Doctoral Student, Department of Pathological Anatomy named after Academician A. I. Strukov

SPIN: 8736-0698

Russian Federation

V. A. Smolyannikova

I. M. Sechenov First Moscow State Medical Universit y, Ministry of Health of the Russian Federation

Email: smva@bk.ru
ORCID iD: 0000-0002-7759-5378
Vera A. Smolyannikova — Dr. Sci. (Med.), Prof., Department of Pathological Anatomy named after Academician A. I. Strukov Russian Federation


  1. Wolff K. L., Goldsmith A. L., Katz S. I., Gilchrest B. A., Paller A. S., Leffell D. J. Fitzpatrick’s Dermatology in General Medicine. 7th ed. New York: McGraw-Hill Medical, 2007. P. 1635–1636.
  2. Roh N. K., Hahn H. J., Lee Y. W., Choe Y. B., Ahn K. J. Clinical and Histopathologocal Investigation of Seborrheic Keratosis. Ann Dermatol. 2016;28(2):152–158.
  3. Elder D., Elenitsas R., Johnson B., Murphy G. F., Xu X. Lever’s histopathology of the skin. 10th ed. Philadelphia: Lippincott-Raven, 2009. P. 795–798.
  4. Muzumdar S., Argraves M., Kristjansson A., Ferenczi K., Dadras S. S. A quantitative comparison between SOX10 and MART-1 immunostaining to detect melanocytic hyperplasia in chronically sun-damaged skin. J Cutan Pathol. 2018;45(4):263–268.
  5. Helm K., Findeis-Hosey J. Immunohistochemistry of pigmented actinic keratoses, actinic keratoses, melanomas in situ and solar lentigines with Melan-A. J Cutan Pathol. 2008;35(10):931–934.
  6. Manaka L., Kadono S., Kawashima M., Kobayashi T., Imokawa G. The mechanism of hyperpigmentation in seborrhoeic keratosis involves the high expression of endothelin-converting enzyme-1alpha and TNF-alpha, which stimulate secretion of endothelin 1. Br J Dermatol. 2001;145(6):895–903.

Copyright (c) 2019 Alexandrova A.K., Smolyannikova V.A.

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.

СМИ зарегистрировано Федеральной службой по надзору в сфере связи, информационных технологий и массовых коммуникаций (Роскомнадзор).
Регистрационный номер и дата принятия решения о регистрации СМИ: серия ПИ № ФС 77 - 60448 от 30.12.2014.

This website uses cookies

You consent to our cookies if you continue to use our website.

About Cookies