Indian Journal of Dermatology
  Publication of IADVL, WB
  Official organ of AADV
Indexed with Science Citation Index (E) , Web of Science and PubMed
 
Users online: 7719  
Home About  Editorial Board  Current Issue Archives Online Early Coming Soon Guidelines Subscriptions  e-Alerts    Login  
    Small font sizeDefault font sizeIncrease font size Print this page Email this page


 
CASE REPORT
Year : 2007  |  Volume : 52  |  Issue : 2  |  Page : 109-110
Genital and perianal melanoacanthomas


1 Department of Skin and VD, KS Hegde Medical Academy, Deralakatte., Mangalore - 574 160, India
2 Department of Pathology, KS Hegde Medical Academy, Deralakatte., Mangalore - 574 160, India
3 Department of General Surgery, KS Hegde Medical Academy, Deralakatte., Mangalore - 574 160, India

Correspondence Address:
Manjunath M Shenoy
Department of Skin and VD, KS Hegde Medical Academy, Deralakatte., Mangalore - 574 160
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0019-5154.33292

Rights and Permissions

   Abstract 

Melanoacanthoma is a benign mixed tumor of melanocytes and keratinocytes. It has been regarded as a rare variety of Seborrheic keratosis. A 50-year-old male presented with multiple asymptomatic pigmented growths on the lower abdomen, inner thighs, external genitals and perianal areas. Histopathology revealed features of melanoacanthoma. The case is being reported for unusual sites of occurrence of an uncommon cutaneous tumor.


Keywords: Genital lesions, melanoacanthoma, seborrheic keratosis


How to cite this article:
Shenoy MM, Teerthanath S, Bhagavan K R. Genital and perianal melanoacanthomas. Indian J Dermatol 2007;52:109-10

How to cite this URL:
Shenoy MM, Teerthanath S, Bhagavan K R. Genital and perianal melanoacanthomas. Indian J Dermatol [serial online] 2007 [cited 2023 Sep 28];52:109-10. Available from: https://www.e-ijd.org/text.asp?2007/52/2/109/33292



   Introduction Top


Melanoacanthomas are among the rare cutaneous tumors. Although melanoacanthoma can be found both on the skin and oral mucosa, oral melanoacanthomas are rare reactive mucosal lesions which demonstrate hyperplasia of spinous keratinocytes and melanocytes and are unrelated to seborrheic keratosis. [1] Cutaneous Melanoacanthomas manifest as pigmented papules, plaques, cutaneous horns or nodules. [2] They are commonly found on the head and trunk areas. Patients are generally asymptomatic and may wait for decades before they seek treatment. Microscopic examination of cutaneous melanoacanthoma reveals a proliferation of keratinocytes and melanocytes localized to the epidermis. Many melanocytes are scattered throughout the tumor lobules rather than localized to the basal layer, a feature that distinguishes melanoacanthomas from other cutaneous tumors.


   Case Report Top


A 50-year-old male presented with multiple asymptomatic pigmented growths on the lower abdomen, inner thighs, external genitals and perianal areas for the past 10 years. To begin with they were flat brownish lesions, which later got elevated. There were no significant medical or surgical problems in the past. On examination there were multiple pigmented verrucous papules, plaques and nodules measuring 0.5 to 6 cm on the lower abdominal wall, root and shaft of penis, left inner thigh and perianal skin [Figure - 1],[Figure - 2]. Lesions in the perianal areas were pedunculated. There were a few slightly elevated flat-topped papular lesions on the penile shaft and scrotum giving a stuck-on appearance. Mucous membranes were devoid of any lesions and there was no lymphadenopathy. Apart from these findings, dermatological and systemic examinations were normal. Keeping the clinical features in view, Seborrheic keratosis and genital warts were considered for differential diagnosis. He was investigated and his complete blood count, renal function test and blood sugar levels were with in normal limits. VDRL and human immunodeficiency virus enzyme-linked immunosorbent assay were non reactive. One of the cutaneous lesions was excised and histopathological examination was carried out. There were hyperkeratosis, acanthosis and papillomatosis with the base of the tumor lying in a straight line with the surrounding normal epidermis [Figure - 3]. These features were suggestive of diagnosis of seborrheic keratosis. The tumor lobule was composed of keratinocytes along with scattered melanocytes a feature that was characteristic of melanoacanthoma.


   Discussion Top


Mishima and Pinkus coined the term melanoacanthoma in 1960 to describe a pigmented, benign proliferation of both keratinocytes and dendritic melanocytes. [2] They are generally regarded as a type of Seborrheic keratosis; however it needs to be distinguished from ordinary pigmented seborrheic keratosis. Melanoacanthomas are rare and have been described more frequently in white patients. [2] They develop in the middle-aged and the elderly like any other type of seborrheic keratosis. They are found mainly on the trunk or head, often on the lip or eyelid.

Microscopically melanoacanthoma are characterized by epidermal proliferation of keratinocytes and melanocytes. Acanthosis, hyperkeratosis, papillomatosis and small horn pearls may also be seen. [2] Many melanocytes are scattered throughout the tumor lobules of a melanoacanthoma rather than localized to the basal layer. These melanocytes are large and highly dendritic and they contain varying amounts of melanin. Two histologic types of melanoacanthomas are described: a diffuse type in which melanocytes are unevenly scattered throughout the lesion and a clonal type in which melanocytes and keratinocytes are clustered in small nests. [2] There was partial or complete disturbance of transfer of melanin from these highly dendritic melanocytes to neighboring keratinocytes. [3] Immunofluorescent studies and a immunoprecipitin assay have shown that melanoacanthomas are not related to malignant melanoma[2], and hence removal by simple excision, curettage or cryotherapy should be curative.

In our case the lesions were up to 6 cm in size and were located in unusual sites like penile shaft and perianal region. Prior to this there is one case report of lesion on penile shaft. [4] We also observed several types of cutaneous lesions like papules, plaques, sessile and pedunculated nodules in the same patients. Surgical excision of bigger lesions was done, and the specimens were sent for histopathologic examination. They also showed features of melanoacanthoma. This case is reported for the unusual sites of occurrence of an uncommon cutaneous tumor.

 
   References Top

1.Fornatora ML, Reich RF, Haber S, Solomon F, Fredman PD. Oral melanoacanthoma: A report of 10 cases, review of the literature and immunohistochemical analysis for HMB-45 reactivity. Am J Dermatopathol 2003;25:12-5.  Back to cited text no. 1      
2.Schwartz RA, Kihiczak GG. Cutaneous melanoacanthoma. Available from: httpwww.emedicine.com/derm/authorid2848,topicid865. [Last updated on 2006 Jun 12]. [Last accessed on 2006 Jun 27].  Back to cited text no. 2      
3.Schlappner OL, Rowden G, Philips TM, Rahim Z. Melanoacanthoma. Ultrastructural and immunological studies. J Cutan Pathol 1978;5:127-41.  Back to cited text no. 3      
4.Vion B, Merot Y. Melanoacanthoma of the penis shaft. Report of a case. Dermatologica 1989;179:87-9.  Back to cited text no. 4      


    Figures

  [Figure - 1], [Figure - 2], [Figure - 3]

This article has been cited by
1 Giant seborrheic keratosis of the genitalia
Nath, A. and Kumari, R. and Rajesh, G. and Thappa, D. and Basu, D.
Indian Journal of Dermatology. 2012; 57(4): 310-312
[Pubmed]
2 Cauliflower like growth in the groins
Rajesh, G. and Kumar, U.M.
Indian Journal of Dermatology, Venereology and Leprology. 2012; 78(5): 661-663
[Pubmed]
3 Seborrhoeic keratosis; A rare cause of conductive deafness
Girisha, B.S. and Shrinath, D.K.P. and Harish, P.S.
Journal of Clinical and Diagnostic Research. 2012; 6(5): 913-914
[Pubmed]
4 Multifocal cutaneous melanoacanthoma with ulceration: A case report with review of literature
Jain, S., Barman, K.D., Garg, V.K., Sharma, S., Dewan, S., Mahajan, N.
Indian Journal of Dermatology, Venereology and Leprology. 2011; 77(6): 699-702
[Pubmed]
5 Pigmented cerebriform growth over forehead
Choudhary, S.V., Bhake, A., Singh, A., Gupta, S.
Indian Journal of Pathology and Microbiology. 2010; 53(2): 375-376
[Pubmed]
6 Pigmented cerebriform growth over forehead
Choudhary, S.V. and Bhake, A. and Singh, A. and Gupta, S.
Indian Journal of Pathology and Microbiology. 2010; 53(2): 375-376
[Pubmed]



 

Top
Print this article  Email this article
 
  Search
 
   Next article
   Previous article 
   Table of Contents
  
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Article in PDF (1,187 KB)
    Citation Manager
    Access Statistics
    Reader Comments
    Email Alert *
    Add to My List *
* Registration required (free)  


    Abstract
    Introduction
    Case Report
    Discussion
    References
    Article Figures

 Article Access Statistics
    Viewed6188    
    Printed235    
    Emailed1    
    PDF Downloaded133    
    Comments [Add]    
    Cited by others 6    

Recommend this journal