|LETTER TO EDITOR
|Year : 2015 | Volume
| Issue : 2 | Page : 37-39
Giant seborrheic keratosis with a new dermoscopic finding
Geethu Francis Alapatt, Ramesh M Bhat, Sukumar Dandekeri, Meryl Sonia Rebello
Department of Dermatology, Father Muller Medical College Hospital, Mangalore, Karnataka, India
|Date of Web Publication||6-Jan-2016|
Geethu Francis Alapatt
Department of Dermatology, Father Muller Medical College Hospital, Mangalore, Karnataka
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Alapatt GF, Bhat RM, Dandekeri S, Rebello MS. Giant seborrheic keratosis with a new dermoscopic finding. Indian J Dermatopathol Diagn Dermatol 2015;2:37-9
|How to cite this URL:|
Alapatt GF, Bhat RM, Dandekeri S, Rebello MS. Giant seborrheic keratosis with a new dermoscopic finding. Indian J Dermatopathol Diagn Dermatol [serial online] 2015 [cited 2021 May 10];2:37-9. Available from: https://www.ijdpdd.com/text.asp?2015/2/2/37/173415
Seborrheic keratoses are the most common benign epidermal tumors. They are a common cause of patient concern because of their variable appearance. They begin as well-circumscribed, dull, flat, tan, or brown patches, becoming more papular as they grow and taking on a waxy verrucous or "stuck on" appearance. 
A 70-year-old woman presented with a slowly progressing verrucous growth on the left breast of 15 years duration. The lesion started as a small pigmented papule that slowly increased in size to become a large verrucous mass. The patient also had morphologically similar but smaller lesions over the trunk and upper arm. She had no history of itching, pain or any associated discharge, bleeding, or ulceration of the lesion.
Dermatological examination revealed a large, hyperpigmented, hard, and non tender verrucous plaque of about 7 cm × 6 cm over the left breast. Mild scaling was present [Figure 1]. Another verrucous plaque about 2 cm × 2 cm was present over the trunk.
|Figure 1: A large, hyperpigmented verrucous plaque with mild scaling, of about 7 cm × 6 cm size over the left breast |
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We made a provisional diagnosis of giant seborrheic keratosis. Dermoscopic examination (Dermalite foto 10×) was carried out that showed cerebriform appearance with fissures and ridges and comedo-like openings that are consistent with seborrheic keratosis [Figure 2]. We also noted a 'parched paddy field appearance' on dermoscopy (16×), which is a new observation [Figure 3].
|Figure 2: Dermoscopic examination (10×) showing cerebriform appearance, fissures, ridges, and comedo-like openings|
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|Figure 3: Dermoscopic examination (16×) showing parched paddy field appearance|
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The histopathological examination of the biopsy samples showed hyperkeratosis, acanthosis, and basaloid cells in cords that were fused. Horn cysts and pseudohorn cysts were also noted. A mild chronic lymphocytic infiltrate was seen in the dermis [Figure 4]. These features were consistent with seborrheic keratosis.
|Figure 4: Histopathological examination showing hyperkeratosis, acanthosis, and basaloid cells in cords that are fused, horn cysts, and pseudo-horn cysts (H&E 10×)|
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Carbon dioxide laser ablation was done and the lesion was removed.
Various studies have been done on seborrheic keratoses. An Australian study has reported an increase in prevalence of seborrheic keratoses from 12% in the age group of 15-25 years to 100% in the age group above 50 years.  The precise etiology and pathogenesis of seborrheic keratoses are not well understood. Genetics, sun exposure, and infection have all been implicated as possible factors. 
A study conducted in south India reported that common seborrheic keratosis was the most common morphological variant (60%) followed by dermatosis papulosa nigra (46.4%), pedunculated seborrheic keratoses (21.2%), flat seborrheic keratoses (10.4%), and stucco keratoses (2%). There was female preponderance in pedunculated seborrheic keratosis and dermatosis papulosa nigra and a slight male preponderance in common seborrheic keratosis, while both sexes were equally affected in flat seborrheic keratosis. 
Dermatoscope is a noninvasive diagnostic tool.  Dermoscopy is a useful tool to confirm the diagnosis of seborrheic keratosis. Only few studies have been undertaken on the dermoscopic findings of seborrheic keratosis. A study conducted by Rajesh et al.  evaluated a total of 250 cases of seborrheic keratosis for all the dermoscopic criteria in different clinical variants. It was seen that comedo-like openings (80%), fissures and ridges (52%), and sharp demarcation of the lesion (82.6%%) were consistent findings in common seborrheic keratosis and less common findings were moth-eaten borders (31.3%), milia-like cysts (24%), and network-like structures (4%). Dermatosis papulosa nigra showed only three findings, comedo-like openings (85.3%), fissures and ridges (78.4%), and sharp demarcation (17.2%). Pedunculated seborrheic keratosis showed only two findings: Fissures and ridges in all lesions and comedo-like openings (64%). Stucco keratoses demonstrated sharp demarcation and network-like structures in all cases (100%), milia-like cysts in 2 cases, and moth-eaten border in one case. 
Braun et al.  in a study evaluated 203 pigmented seborrheic keratoses and reviewed the dermoscopic criteria. The authors found high prevalence of classic dermoscopic features such as comedo-like openings (71%) and milia-like cysts (66%). They suggested that in addition to these, other dermoscopic criteria such as fissures and ridges (61%), hairpin blood vessels (63%), sharp demarcation of lesions (90%), moth-eaten border (46%), would improve diagnostic accuracy and reduce the misclassification into melanocytic lesions. 
In our case apart from the classical dermoscopic features of fissures and ridges and comedo-like openings, we also noticed a parched paddy field-like appearance on dermoscopy in our patient.
Incisional biopsy of the lesion and histopathology has been recommended to rule out malignancy.
Our case highlights the massive size of the lesion, its presence over the breast, the utility of a dermatoscope in assisting with diagnosis and a new observation of a 'parched paddy field appearance' on dermoscopy that may be due to the large size of the lesion. To the best of our knowledge, this dermoscopic feature has not been reported before.
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Conflicts of interest
There are no conflicts of interest.
| References|| |
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]