Ann Dermatol Vol. 23, Suppl. 3, 2011 CASE REPORT Sebaceous Hyperplasia of the Scrotum and Penile Shaft http://dx.doi.org/10.5021/ad.2011.23.S3.S341 Sebaceous Hyperplasia of the Scrotum and Penile Shaft Hei Sung Kim, M.D., Jun Young Lee, M.D., Hyung Ok Kim, M.D., Young Min Park, M.D. Department of Dermatology, Seoul St. Mary’s Hospital, The Catholic University of Korea School of Medicine, Seoul, Korea Sebaceous hyperplasia (SH) is a proliferative abnormality of sebaceous glands, most often seen in elderly individuals. It consists of single or multiple, asymptomatic, small yellow papules with a central depression. The face is most com- monly affected, but there have been reports of SH on the chest or genitalia. A lobular array of well-differentiated ma- ture sebaceous lobules is noted on histological preparations. In this report, we describe a patient with SH on the penile shaft and parts of the scrotum. (Ann Dermatol 23(S3) S341∼ S342, 2011) -Keywords- Penis, Scrotum, Sebaceous hyperplasia INTRODUCTION Although dermatology textbooks state that sebaceous hy- perplasia (SH) is a common normal variant on scrotal skin, many Korean dermatologists consider it rare due to the limited number of reports in Korea. In this report, we describe a patient with SH on the scrotum and penile shaft as a reference case. CASE REPORT A 26-year-old man was concerned with an increasing number of yellowish papules on his penile shaft without Received January 7, 2011, Revised February 13, 2011, Accepted for publication April 25, 2011 Corresponding author: Young Min Park, Department of Dermatology, Seoul St. Mary’s Hospital, 505 Banpo-dong, Seocho-gu, Seoul 137- 701, Korea. Tel: 82-2-2258-6223, Fax: 82-2-594-3255, E-mail: yymm- park6301@hotmail.com This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http:// creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. any related symptoms for 2 years. He denied any medical history or manipulation of the site. No family history with a similar disorder was reported. On physical examination, numerous, 1∼2 mm-sized papules presented on the pro- ximal half of the penile shaft and parts of the scrotum. The papules were smooth and soft on palpation; a central umbilication was not definite, and many were located around the pubic hair (Fig. 1). We performed a skin biop- sy from a representative yellow papule. A microscopic ex- amination showed a lobulated lesion composed of enlar- ged sebaceous glands (＞4 around each pilosebaceous unit) extending down into the dermis. The cells were pre- dominantly mature sebocytes with a peripheral germina- tive layer. The cells displayed a foamy, vesiculated cyto- plasm and a central nucleolus with no atypical features (Fig. 2). Serial sections further showed that the sebaceous lobules were connected with a central pilosebaceous folli- cle. Based on this evidence, a diagnosis of SH was made. DISCUSSION Sebaceous glands form part of the skin appendages. They present in large numbers on the face, scalp, and ears in association with hair structures1-4. Free sebaceous glands (those not associated with the hair follicle) are occasi- onally found in some areas of modified skin, such as the nipple (Montgomery tubercles), lips (Fordyce’s spots), and the inner surface of the prepuce (Tyson’s glands)5. Facial SH in the elderly is due to decreased cellular turnover secondary to reduced androgen levels, with a resulting increase in gland size6. However, this does not explain the hyperplasia that occur in the glands of the penile shaft. In contrast to facial lesions, the majority of penile SH cases seem to appear at an earlier age. Higher sensitivity of the sebaceous cells to androgens, leading to an increase in cellular proliferation may be a possible cause of penile SH7. Inflammatory stimulation by CD8＋ lymphocytes also plays a role8. The clinical differential diagnosis includes milium, lichen Vol. 23, Suppl. 2, 2011 S341