Background: Lichenoid keratosis (LK) is a well-described entity that has been proposed to represent a regressive response to a pre-existent epidermal lesion. Aims: To evaluate the natural evolution of a series of cases showing the intermediate stage of the regression of seborrheic keratosis in LK using sequential dermoscopy imaging over time. Material and Methods: A series of lesions with dermoscopic areas of seborrheic keratosis and LK in the same tumor were consecutively collected for over 3 years at the Dermatology Department of the Hospital de Sant Pau i Santa Tecla, Tarragona, Spain. Sequential dermoscopic images of each case were collected quarterly for 1 year. At the end of the follow-up, all the lesions were biopsied. Results: A total of 22 cases were collected. At the end of the follow-up, the LK part increased in all the lesions. In 11 cases (50%), the seborrheic keratosis part disappeared completely, and in another 5 cases (22.7%), seborrheic keratosis comprised only 10% of the remaining area. Conclusions: These dermoscopic study findings support the proposal that LK represents a regressive response to a pre-existent epidermal lesion, in this case seborrheic keratosis.

1.
Lumpkin LR, Helwig EB: Solitary lichen planus. Arch Dermatol 1966;93:54–55.
2.
Shapiro L, Ackerman AB: Solitary lichen planus-like keratosis. Dermatologica 1966;132:386–392.
3.
Prieto VG, Casal M, McNutt NS: Lichen planus-like keratosis: a clinical and histological reexamination. Am J Surg Pathol 1993;17:259–263.
4.
Mehregan AH: Lentigo senilis and its evolution. J Invest Dermatol 1975;65:429–433.
5.
Goette DK: Benign lichenoid keratosis. Arch Dermatol 1980;116:780–782.
6.
Jang KA, Kim SH, Choi JH, Sung KJ, Moon KC, Koh JK: Lichenoid keratosis: a clinicopathologic study of 17 patients. J Am Acad Dermatol 2000;43:511–516.
7.
Morgan MB, Stevens GL, Switlyk S: Benign lichenoid keratosis: a clinical and pathologic reappraisal of 1,040 cases. Am J Dermatopathol 2005;27:387–392.
8.
Malvehy J, Puig S, Argenziano G, Bauer R, Blum S, Botella R, et al: Principles of Dermoscopy. Barcelona, GEDE, 2002.
9.
Elgart GW: Seborrheic keratoses, solar lentigines, and lichenoid keratoses: dermatoscopic features and correlation to histology and clinical signs. Dermatol Clin 2001;19:347–357.
10.
Zaballos P, Blázquez S, Puig S, Salsench E, Rodero J, Vives JM, Malvehy J: Dermoscopic pattern of intermediate stage in seborrhoeic keratosis regressing to lichenoid keratosis: report of 24 cases. Br J Dermatol 2007;157:266–272.
11.
Panizzon R, Skaria A: Solitary lichenoid benign keratosis: a clinicopathological investigation and comparison to lichen planus. Dermatologica 1990;181:284–288.
12.
Bugatti L, Filosa G: Dermoscopy of lichen planus-like keratosis: a model of inflammatory regression. J Eur Acad Dermatol Venereol 2007;21:1392–1397.
13.
Frigy AF, Cooper PH: Benign lichenoid keratosis. Am J Clin Pathol 1985;83:439–443.
14.
Laur WE, Posey RE, Waller JD: Lichen planus-like keratosis: a clinicohistopathologic correlation. J Am Acad Dermatol 1981;4:329–336.
15.
Goldenhersh MA, Barnhill RL, Rosenbaum HM, Etenn KS: Documented evolution of a solar lentigo into a solitary lichen planus-like keratosis. J Cutan Pathol 1986;13:308–311.
16.
Zaballos P, Rodero J, Pastor L, Vives JM, Puig S, Malvehy J: Dermoscopy of lichenoid regressing solar lentigines. Arch Dermatol 2008;144:284.
17.
Schiffner R, Schiffner-Rohe J, Vogt T, Landthaler M, Wlotzke U, Cognetta AB, Stolz W: Improvement of early recognition of lentigo maligna using dermatoscopy. J Am Acad Dermatol 2000;42:25–32.
18.
Raptoulis G, Spencer R, Einstein B, Oliviero M, Braun R, Rabinovitz H: Lichen planus-like keratosis of the face: a simulator of melanoma in situ. Dermatol Surg 2007;33:854–856.
19.
Bayer-Garner IB, Ivan D, Schwartz MR, Tschen JA: The immunopathology of regression in benign lichenoid keratosis, keratoacanthoma and halo nevus. Clin Med Res 2004;2:89–97.
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.