Folliculosebaceous Cystic Hamartoma on the Nipple Seung Yoon Lee, MD, Doo Rak Lee, MD, Chung Eui You, MD, Mi Youn Park, MD, Phd, and Sook Ja Son, MD, Phd

EXTRAORDINARY CASE REPORT

Folliculosebaceous Cystic Hamartoma on the Nipple Seung Yoon Lee, MD, Doo Rak Lee, MD, Chung Eui You, MD, Mi Youn Park, MD, PhD, and Sook Ja Son, MD, PhD

(Am J Dermatopathol 2006;28:205–207)

CASE REPORT A 31-year-old woman visited our clinic for an asymptomatic, projecting tumor on the left nipple that had been present for 15 years. It had developed as a tiny papule and enlarged slowly for over 13 years. During the next 2 years it grew rapidly. There was no size variation relating to menstrual cycle or her pregnancy. The lesion was a 0.9 Â 0.5 cm, pinkish to light brown, soft tumor with a projecting and papillomatous configuration, located on the superiomedial aspect of the left nipple (Fig. 1). It did not involve the ductal orifice and was not tender to pressure. On squeezing, scanty amounts of thick, whitish material came out from the tumor, which had a different nature from that of milk. The tumor was totally excised and no evidence of FIGURE 1. Skin-colored, papillomatous-surfaced, projecting recurrence was detected until 3 months later. On histopathologic tumor on the superiomedial aspect of the left nipple (the scale examination, epidermal proliferation and hyperplasia of col- is shown in centimeters). lagen-rich connective tissue was observed. Within the hyper- plastic dermis, there was a large infundibulocystic structure lined by stratified squamous epithelium, which contained horny material and was connected directly to the epidermis (Fig. 2A). 1,2 1 Sebaceous lobules were attached to the cystic structure via venules. Since Kimura et al first described FCH in sebaceous ducts, some of which were small and composed of 1991, over 30 cases have been reported in the litera- only a few sebocytes. The surrounding stroma consisted of ture.1–10 The typical FCH presents as a solitary, flesh- concentric, fibrillary bundles of collagen, and included numer- colored, smooth-surfaced papule or nodule with a sessile ous dilated capillaries and venules (Fig. 2B). The perifollicular or pedunculated shape.1 This hamartoma usually occurs part of the stroma contained large amounts of mucin, which was on the head, especially on the central part of the face and stained positively with Alcian blue. A mild round cell infiltrate nose.2 Some cases on the upper back, forearm, ear, and was observed in the altered stroma. Clefts separated the stroma 6–10 from adjacent compressed fibrous tissue. Serial sections showed labia majora have been reported. some horn cystlike structures with immature pilosebaceous To our knowledge, this is the first report of FCH on complexes (Fig. 3). The surrounding connective tissue contained the nipple. Until now, some benign tumors on the nipple numerous smooth muscle bundles and a lactiferous duct, have been reported including florid papillomatosis, characteristic histologic features of the nipple. leiomyoma, and fibroma.11 In its clinical manifestation, our case mimicked the fibroma on the nipple described by 11 DISCUSSION Doctor and Sirsat, except for the fact that our case was not accompanied by any subjective symptoms. However, Folliculosebaceous cystic hamartoma (FCH) is a the histopathologic feature of our case was obviously distinctive cutaneous hamartoma of follicular, sebaceous, distinct from that of fibroma or other previously and mesenchymal components.1,2 This hamartoma is described nipple tumors. Another tumor that can characterized by infundibulosebaceous cystic prolifera- resemble our case is adnexal polyp of neonatal skin.12,13 tion with specific mesenchymal changes including packed This can be ruled out clinically, in that it occurs fibrillary bundles of collagen, cleft formation between exclusively in neonates or infants and falls off sponta- fibroepithelial units and surrounding stroma, sparsely neously within a few days. Furthermore, it usually distributed adipocytes, and increased numbers of small appears on the areola, not on the nipple itself. This tumor is histologically different from FCH in that it does From the National Medical Center, Seoul, Republic of Korea. not always have sebaceous glands and usually contains Reprints: Sook Ja Son, MD, PhD, Department of Dermatology, well-developed eccrine glands. Additionally, there are no National Medical Center, 18-79 Euljiro 6-ga, Jung-ku, Seoul 100- 799, Republic of Korea (e-mail: [email protected]). epithelial strands budding from the follicles in this 12 Copyright r 2006 by Lippincott Williams & Wilkins tumor.

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FIGURE 3. Serial section showing some horn cystlike structures with immature pilosebaceous complexes (H&E stain).

located, epithelium-lined cavity radiates many well- differentiated sebaceous follicles that include sebaceous acini and ducts, follicular infundibula, and hair follicle units.14 Obvious mesenchymal changes are not found in sebaceous trichofolliculoma. Fibrofolliculoma displays a concentric, perifollicular arrangement of thick collagen bundles in the stroma.15–17 An anastomosing pattern of thin epithelial strands and aberrant follicular structures are char- acteristics of this tumor. Trichodiscoma is a rare hamartoma of the dermal portion of the hair disc, which presents as an area of fine, fibrillary, hyaluronic acid-rich connective tissue contain- FIGURE 2. A, Hematoxylin and eosin (H&E) stain showing a ing thick-walled, ectatic blood vessels.18 A hair follicle is large infundibulocystic structure attached to the sebaceous usually present at the margin of the lesion. lobules via sebaceous ducts. B, High magnification of (A) Perifollicular fibroma is a rare, hamartomatous showing the altered stroma containing fibrillary bundles of 19 collagen, mucinous material, and increased number of dilated proliferation of the pilar connective tissue sheath. It is capillaries and venules. characterized by a concentric arrangement of collagen fibers surrounding hair follicles. However, it shows neither prominent sebaceous components nor immature pilosebaceous units. Our case showed the typical clinical feature of FCH, In this case, the differential diagnosis of the tumor namely a small, asymptomatic, papillomatous-surfaced, also includes a Montgomery tubercle because of its and pedunculated tumor.1,2 Histopathologically it ful- particular location and histopathologic findings. Mont- filled the diagnostic features of FCH suggested by gomery tubercles have similar histologic features as FCH, Kimura et al,1 although its mesenchymal component including sebaceous lobules associated with follicular around the fibroepithelial unit was not sufficient enough epithelium.20 In particular, Steffen and Ackerman20 to characterize the double clefts in FCH. Admixed described an example of a Montgomery tubercle located adipocytes, one of the specific findings of FCH, were in a supernumerary nipple, with histologic features not found in our case, which might be because the nipple similar to those of this case. However, there are some originally contains few fat cells. Serial sections displayed specific findings that help us diagnose the tumor in this immature pilosebaceous units budding from the infundi- case as an FCH rather than a Montgomery tubercle: (a) bulocystic structure, which appear similarly in other the mesenchymal change around the fibroepithelial unit follicular hamartomas such as sebaceous trichofolliculo- characterizing FCH was found in its stroma, namely, ma, fibrofolliculoma, trichodiscoma, and perifollicular more small blood vessels, prominent proliferation of fibroma. fibrocytes, and a delicate meshwork of fine collagen Sebaceous trichofolliculoma is most frequently bundles; (b) the positive result of Alcian blue staining in confused with FCH. In this tumor, a large, centrally the altered stroma indicates deposits of mucosubstances,

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21 which is one of the characteristic features of FCH ; (c) 6. Yamamoto O, Suenaga Y, Bhawan J. Giant folliculosebaceous the somewhat aberrant configuration of the peripheral cystic hamartoma. J Cutan Pathol. 1994;21:170–172. sebaceous lobules and the presence of radiating immature 7. Sturtz DE, Smith DJ, Calderon MS, et al. Giant folliculosebaceous cystic hamartoma of the upper extremity. J Cutan Pathol. pilosebaceous complexes also suggest an FCH rather than 1,3,4,9,21 2004;31:287–290. a Montgomery tubercle ; (d) a connection of an 8. Donati P, Balus L. Folliculosebaceous cystic hamartoma: reported infundibulum with a lactiferous duct arising from under- case with a neural component. Am J Dermatopathol. 1993; lying mammary lobules was not shown in this case, which 15:277–279. 20,22 9. Aloi F, Tomasini C, Pippione M. Folliculosebaceous cystic is a feature often seen in a Montgomery tubercle. In hamartoma with perifollicular mucisnosis. Am J Dermatopathol. clinical appearance, the location of the tumor is not 1996;18:58–62. compatible with a Montgomery tubercle, which mostly 10. Bolognia JL, Longley BJ. Genital variant of folliculosebaceous arises on the areola, not on the nipple itself, although cystic hamartoma. Dermatology. 1998;197:258–260. Steffen and Ackerman20 reported one example in 11. Doctor VM, Sirsat MV. Florid papillomatosis (adenoma) and other benign tumours of the nipple and areola. Br J Cancer. 1971;25:1–9. a supernumerary nipple. Additionally, we could not 12. Hidano A, Kobayashi T. Adnexal polyp of neonatal skin. Br J observe any symptomatic changes related to pregnancy, Dermatol. 1975;92:659–662. whereas a Montgomery tubercle is known to become 13. Koizumi H, Itoh E, Ohkawara A. Adnexal polyp of neonatal skin prominent and often secrete milk during pregnancy.22 observed beyond the neonatal period. Acta Derm Venereol. 1998;78:391–392. Considering its specific histologic features along with the 14. Plewig G. Sebaceous trichofolliculoma. J Cutan Pathol. 1980; clinical manifestation, the tumor in this case seems to be 7:394–403. an FCH rather than a Montgomery tubercle. 15. Scully K, Bargman H, Assad D. Solitary fibrofolliculoma. JAm This case was unique in that the FCH occurred on Acad Dermatol. 1984;11:361–363. the nipple. We consider it as an extraordinary case that 16. Birt AR, Hogg GR, Dube J. Hereditary multiple fibrofolliculomas with trichodiscomas and acrochordons. Arch Dermatol. has never been reported before. It is particularly 1977;113:1674–1677. remarkable that a follicular hamartoma, which usually 17. Fujita WH, Barr RJ, Headley JL. Multiple fibrofolliculomas with occurs on a hair-bearing site such as the face and scalp, trichodiscomas and acrochordons. Arch Dermatol. 1981;117:32–35. arose from a non–hair-bearing site as the nipple. 18. Pinkus H, Coskey R, Burgess GH. Trichodiscoma: a benign tumor related to the haarscheibe (hair disk). J Invest Dermatol. 1974;63:212–218. REFERENCES 19. Junkins-Hopkins JM, Cooper PH. Multiple perifollicular fibromas: 1. Kimura T, Miyazawa H, Aoyagi T, et al. Folliculosebaceous cystic report of a case and analysis of the literature. J Cutan Pathol. hamartoma: a distinctive malformation of the skin. Am J 1994;21:467–471. Dermatopathol. 1991;13:213–220. 20. Steffen C, Ackerman AB. Fordyce’s spots and Montgomery’s 2. Templeton SF. Folliculosebaceous cystic hamartoma: a clinical tubercles. In: Steffen C, Ackerman AB, eds. Neoplasms With pathologic study. J Am Acad Dermatol. 1996;34:77–81. Sebaceous Differentiation. Philadelphia, PA: Lea & Febiger; 3. Yamamoto T, Ohkubo H, Nishioka K. Folliculosebaceous cystic 1994:71–86. hamartoma associated with rosacea. J Dermatol. 1993;20:712–714. 21. Steffen C, Ackerman AB. Folliculosebaceous cystic hamartoma. In: 4. Toyoda M, Morohashi M. Folliculosebaceous cystic hamartoma Steffen C, Ackerman AB, eds. Neoplasms With Sebaceous Differ- with a neural component: an immunohistochemical study. entiation. Philadelphia, PA: Lea & Febiger; 1994:183–202. J Dermatol. 1997;24:451–457. 22. Smith DM, Peters TG, Donegan WL. Montgomery’s areolar 5. Ramdial PK, Chrystal V, Madaree A. Folliculosebaceous cystic tubercle: a light microscopic study. Arch Pathol Lab Med. hamartoma. Pathology. 1998;30:212–214. 1982;106:60–63.

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