Home About us Editorial board Search Ahead of print Current issue Archives Submit article Instructions Subscribe Contacts Login 
  • Users Online: 174
  • Home
  • Print this page
  • Email this page

 Table of Contents  
Year : 2020  |  Volume : 7  |  Issue : 1  |  Page : 19-22

Genital porokeratosis: A report of two cases and review of literature

Department of Dermatology, Venereology and Leprosy, Government Medical College, Nagpur, Maharashtra, India

Date of Submission26-May-2019
Date of Decision28-Aug-2019
Date of Acceptance28-Oct-2019
Date of Web Publication02-Jun-2020

Correspondence Address:
Sumit A Hajare
Department of Dermatology, Venereology and Leprosy, Government Medical College, Nagpur, Maharashtra
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/ijdpdd.ijdpdd_29_19

Rights and Permissions

Porokeratosis (PK) is an uncommon disorder of keratinization that presents with keratotic papules or annular plaques that expand centrifugally with a thread-like elevated border. Genital involvement in PK is a rare occurrence even in disseminated forms. We encountered two patients who had PK primarily affecting the genital area. Both cases were males out of which one case had involvement of the scrotum and thigh and other case had only scrotal involvement. The cases were difficult to diagnose clinically, but dermoscopy was helpful and was further confirmed on histopathology.

Keywords: Cornoid lamella, ptychotropic porokeratosis, thread-like border

How to cite this article:
Roge RP, Hajare SA, Mukhi JI, Singh RP. Genital porokeratosis: A report of two cases and review of literature. Indian J Dermatopathol Diagn Dermatol 2020;7:19-22

How to cite this URL:
Roge RP, Hajare SA, Mukhi JI, Singh RP. Genital porokeratosis: A report of two cases and review of literature. Indian J Dermatopathol Diagn Dermatol [serial online] 2020 [cited 2021 Oct 17];7:19-22. Available from: https://www.ijdpdd.com/text.asp?2020/7/1/19/285795

  Introduction Top

Porokeratosis (PK) is an uncommon clonal disorder of keratinization characterized by one or multiple atrophic patches surrounded by a distinct ridge-like border clinically and cornoid lamella on histopathological examination.[1] The common clinical variants include classical plaque-type PK of Mibelli, linear PK, disseminated superficial PK, PK palmaris et plantaris disseminata, and punctate PK.[2] Genitogluteal PK (GP) is classified into three types, namely classical PK on the genital region, ptychotropic PK, and penoscrotal PK.[3] We report such an occurrence of GP in two male patients.

  Case Reports Top

Case 1

A 48-year-old male presented with multiple dark-colored raised lesions on the scrotum and thighs since 2 years. The lesions were asymptomatic, and there was no history of extramarital sexual exposure. The patient was previously treated as tinea cruris and lichen simplex chronicus of scrotum with no improvement. On examination, the patient had well-defined hyperpigmented papules and plaques of varying sizes over scrotum and thighs [Figure 1]. The largest plaque of size 2 cm × 3 cm was seen over the left thigh, and lesions over thighs showed mildly scaly, atrophic center with raised borders. Single well-defined papule with verrucous surface is seen on the right inguinal area [Figure 2]. The patient was further evaluated with a differential diagnosis of scrotal PK, psoriasis, and annular lichen planus.
Figure 1: (a) Two well-defined hyperpigmented plaques with double marginated thread-like border present over the left thigh along with hyperpigmented papules over scrotum. (b) Multiple well defined hyperpigmented papules over the scrotum

Click here to view
Figure 2: Single well-defined papule with verrucous surface present over the right inguinal area and hyperpigmented plaques with thread-like border present over left and right thigh

Click here to view

Dermatoscopy (MINI 3000 LED Dermatoscope, HEINE, Germany) of scrotal lesions showed brown-colored center of plaque with irregularly folded double marginated white track-like border, as shown in [Figure 3]. Skin punch biopsy was taken from lesion over scrotum which showed epidermal invaginations with multiple columns of parakeratosis (multiple cornoid lamellae) and underlying hypogranulosis with dyskeratotic cells in spinous layer and mild perivascular infiltrate [Figure 4]. Based on clinical, dermoscopic, and histopathological evaluation, the diagnosis of genital PK was made. The patient was treated with topical 5-fluorouracil (5-FU) for 6 months and further oral acitretin with topical 5-FU for 3 months with no clinical improvement. The patient was further referred to the plastic surgery department for excision.
Figure 3: Well-defined plaque with brownish center and irregularly folded double marginated white track-like border

Click here to view
Figure 4: (a) Low-power view (×4) showing epidermal invaginations with multiple columns of parakeratosis (multiple cornoid lamella) and underlying hypogranulosis. (b) High-power view showing multiple cornoid lamella and hypogranulosis with dyskeratotic cells in upper spinous layer and lichenoid infiltrate between the lamella

Click here to view

Case 2

A 24-year-old male presented with multiple raised lesion with mild itching over scrotum since 12 months. The patient was earlier treated as tinea cruris, lichen simplex chronicus of scrotum, and psoriasis from private clinics. He was prescribed topical steroids, antifungal, and antibiotic creams with no improvement. On examination, the patient had multiple well-defined papules and plaques over scrotum having dry, verrucous surface, and the largest plaque was 1.5 cm × 1 cm in size [Figure 5]. Cutaneous examination at other sites and mucosae was normal. Dermoscopy of the scrotal lesion showed plaque with elevated double marginated white track-like border suggestive of scrotal PK, as shown in [Figure 6]. Skin punch biopsy from the edge of the lesion showed multiple cornoid lamellae with hypogranulosis and underlying dyskeratotic cells in the spinous layer [Figure 7]. Based on clinical and histopathological examination, the final diagnosis of scrotal PK was made. The patient was treated with surgical excision.
Figure 5: Multiple well-defined papules present over the scrotum (Case 2)

Click here to view
Figure 6: Well-defined plaque with elevated double marginated white track-like border

Click here to view
Figure 7: (a) Epidermal invaginations with multiple cornoid lamella and hypogranulosis. (b) High magnification view showing cornoid lamella with dyskeratotic cells in upper spinous layers

Click here to view

  Discussion Top

Neuman was the first to describe the disease and later Italian dermatologist, Mibelli coined the term PK considering the involvement of ostia of eccrine duct.[4],[5] It is an autosomal dominant disorder of keratinization of unknown etiology having unpredictable course and presents as a keratotic papule or annular plaque with a thread-like elevated border that expands centrifugally resembling the Great Wall of China.[6]

In 1985, Helfman and Poulos described reticular PK affecting the genital and pelvic region.[7] Since then, about 50 of genital PK has been published in literature.[3] Lucker et al. coined the term “porokeratosis ptychotropica” from the Greek word “ptyche” (fold) and “trope” (turning) to describe the flexural variant of PK.[8] Etiopathogenesis of PK is obscure but certainly complex and multifactorial. It has been suggested that the lesions of PK result from the peripheral expansion of an abnormal, mutant clone of epidermal keratinocytes located at the base of the parakeratotic column. The incidence of Bowen's disease and squamous cell and spinous cell carcinomas is 6.8%–11% in this disease.[9]

Overall, GP is rare, seen two to three times more common in males than in females. PK localized to the male genitalia has been reported most commonly in the scrotum, followed by penis, buttock, natal cleft, groins, and adjacent thighs.[1] In our cases, PK was localized to the scrotum and/or thigh. Dermoscopy of genital PK shows central brown pigmentation with areas of blue-gray dots and a white track at the periphery. Histopathology shows epidermal invaginations with columns of parakeratosis and underlying hypogranulosis with dyskeratotic cells in the spinous layer.[3] A lichenoid infiltrate between the cornoid lamellae and mild perivascular inflammatory infiltrate can be seen. Multiple cornoid lamellae are a feature of genital and ptychotropic PK.

Clinically, none of the cases were easy to diagnose. In both cases, the annular plaques had raised borders, but the typical ridge was not seen with the naked eye. While evaluating a case of annular plaques over scrotum, the differential diagnosis of annular lichen planus, annular syphilide, psoriasis, lichen simplex chronicus, and verruca vulgaris should be considered. The treatment options of GP are cryotherapy, topical 5% 5-FU or imiquimod, CO2 laser ablation, and surgical excision.[10],[11]

We found that all our patients had been previously treated with antifungals, antibiotics, and topical and systemic steroids. This highlights the possibility that PK confined to the genital area is an under-diagnosed entity and can be easily confused with sexually transmitted diseases and other nonvenereal diseases affecting genitalia. PK can be easily misdiagnosed so thorough clinical evaluation is mandatory, dermoscopic examination is a helpful aid in diagnosis, and skin biopsy is required for confirmation. In addition, keeping in mind, the potential for malignancy, all diagnosed cases should receive regular follow-up.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

Sengupta S, Das JK, Gangopadhyay A. Porokeratosis confined to the genital area: A report of three cases. Indian J Dermatol Venereol Leprol 2008;74:80.  Back to cited text no. 1
[PUBMED]  [Full text]  
Ahmed A, Hivnor C. A case of genital porokeratosis and review of literature. Indian J Dermatol 2015;60:217.  Back to cited text no. 2
[PUBMED]  [Full text]  
Joshi R, Minni K. Genitogluteal porokeratosis: A clinical review. Clin Cosmet Investig Dermatol 2018;11:219-29.  Back to cited text no. 3
Khanna U, D'Souza P, Dhali TK. Genital porokeratosis: A distinct clinical variant?. Indian J Dermatol 2015;60:314-5.   Back to cited text no. 4
[PUBMED]  [Full text]  
Vaishnani JB, Bosamiya SS, Sapariya BJ, Udhreja PR. Linear porokeratosis with follicular involvement. Indian J Dermatol 2011;56:460-1.   Back to cited text no. 5
[PUBMED]  [Full text]  
Tebet AC, Oliveira TG, Oliveira AR, Moriya FS, Oliveira J Filho, Cucé LC. Porokeratosis ptychotropica. An Bras Dermatol 2016;91:134-6.  Back to cited text no. 6
Helfman RJ, Poulos EG. Reticulated porokeratosis. A unique variant of porokeratosis. Arch Dermatol 1985;121:1542-3.  Back to cited text no. 7
Lucker GP, Happle R, Steijlen PM. An unusual case of porokeratosis involving the natal cleft: Porokeratosis ptychotropica? Br J Dermatol 1995;132:150-1.  Back to cited text no. 8
Bhaskar S, Jaiswal AK, Raj N, Reddy D. Porokeratosis – Head to toe: An unusual presentation. Indian Dermatol Online J 2015;6:101-4.  Back to cited text no. 10
Cabete J, Fidalgo A, Lencastre A, Diamantino F, João A. Porokeratosis ptychotropica of the scrotum: Dermoscopic evaluation of an atypical presentation. An Bras Dermatol 2015;90:191-3.  Back to cited text no. 11
[PUBMED]  [Full text]  
Dongre A, Adhe V, Sanghavi S. Genital porokeratosis: A rare entity. Indian J Dermatol 2013;58:81.  Back to cited text no. 12


  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7]


Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

  In this article
Case Reports
Article Figures

 Article Access Statistics
    PDF Downloaded129    
    Comments [Add]    

Recommend this journal