Giant acquired digital fibrokeratoma occurring on the left great toe.
ABSTRACT Acquired digital fibrokeratoma is an uncommon, benign fibrous tumor which usually occurs in adults as a solitary lesion. The most frequent locations are fingers and toes and the size of the tumor is generally small, around 3~5 mm. An 18-year-old female presented with a solitary, skin-colored, round and protruded nodule of the left great toe. The size of nodule was 2.5×1.6×1.4 cm. Histopathologic examination revealed typical findings of acquired digital fibrokeratoma. Herein, we report a giant acquired digital fibrokeratoma.
Received December 28, 2009, Revised January 24, 2010, Accepted for
publication January 28, 2010
Corresponding author: Deborah Lee, M.D., Department of Derma-
tology, Busan Paik Hospital, College of Medicine, Inje University,
633-165 Gaegum-dong, Busanjin-gu, Busan 614-735, Korea. Tel:
82-51-890-6135, Fax: 82-51-897-6391, E-mail: firstname.lastname@example.org
Ann DermatolVol. 23, No. 1, 2011DOI: 10.5021/ad.2011.23.1.64
Fig. 1. Skin-colored, 2.5×1.6×1.4 cm sized, solitary, round and
protruded nodule on the lateral side of the left great toe.
Giant Acquired Digital Fibrokeratoma Occurring on the
Left Great Toe
Joon Hee Choi, M.D., So Young Jung, M.D.1, Ji Sung Chun, M.D.1, Jong Keun Seo, M.D.1,
Deborah Lee, M.D.1, Seon Wook Hwang, M.D.1, Ho Suck Sung, M.D.1
Department of Dermatology, Maryknoll Hospital, 1Department of Dermatology, Busan Paik Hospital, College of Medicine, Inje University,
Acquired digital fibrokeratoma is an uncommon, benign
fibrous tumor which usually occurs in adults as a solitary
lesion. The most frequent locations are fingers and toes and
the size of the tumor is generally small, around 3∼5 mm. An
18-year-old female presented with a solitary, skin-colored,
round and protruded nodule of the left great toe. The size of
nodule was 2.5×1.6×1.4 cm. Histopathologic examination
revealed typical findings of acquired digital fibrokeratoma.
Herein, we report a giant acquired digital fibrokeratoma.
(Ann Dermatol 23(1) 64∼∼66, 2011)
Acquired digital fibrokeratoma, Great toe
Acquired digital fibrokeratoma is rare, benign fibrous
tumor. It commonly occurs in adults as a solitary nodule
on fingers and toes1,2. The size of the tumor is generally
small, less than 1 cm. Even though an exact definition of
the standard size of giant acquired digital fibrokeratoma
has not been established, 3 cases of acquired digital
fibrokeratoma larger than 1 cm were reported, as giant
acquired digital fibrokeratomas, in the dermatologic
Herein, we report the biggest case in Korean dermatologic
literature of a giant acquired digital fibrokeratoma occurr-
ing on the left great toe.
An 18-year-old woman presented with an asymptomatic,
solitary nodule on her left great toe. Two years ago, she
noticed a slow growing, flesh-colored nodule on her left
great toe. There was no history of trauma. One year ago
the lesion was totally excised. After several months, the
lesion recurred and gradually enlarged. Physical examina-
tion revealed a 2.5×1.6×1.4 cm sized, skin-colored,
solitary, round and protruded nodule on the lateral side of
her left great toe (Fig. 1).
Histopathologic examination showed marked hyperkera-
tosis, acanthosis and elongated rete ridges in the epider-
mis (Fig. 2). The dermis showed thick collagen bundles
with dilated capillaries oriented in the direction of the
longitudinal axis of the lesion. The histopathologic fea-
tures were compatible with acquired digital fibrokera-
toma. The lesion was completely excised without recur-
rence for 1 year.
Giant Acquired Digital Fibrokeratoma Occurring on the Left Great Toe
Vol. 23, No. 1, 2011
Fig. 2. (A) Histopathologic examination demonstrated a dome-shaped tumor consisting of a thick core lesion and peripheral lesion
(H&E, ×4). (B) The core of tumor showed thick dermal collagen bundles oriented along the longitudinal axis of the lesion (H&E,
×40). (C) The peripheral lesion of tumor showed irregular acanthosis, thickening of rete ridges and increased capillaries (H&E, ×40).
(D) The close-up view of the peripheral lesion showed thin walled dilated capillaries and thick collagen bundles in dermis (H&E,
Acquired digital fibrokeratoma is an uncommon tumor
first reported by Bart et al.1 in 1968. It is a benign tumor,
almost always solitary, can be seen in adults and does not
show spontaneous regression. In most cases, acquired
digital fibrokeratoma appears as a small solitary nodules
mainly on the fingers and toes, occasionally occurring on
the lower lip, nose, elbow, pre-patellar area, nail bed and
The size of acquired digital fibrokeratoma is generally
small, less than 1 cm. Exceptionally, there have been
reported cases of giant acquired digital fibrokeratoma.
Kakurai et al.4 and Bron et al.3 reported 3.2×3.8×1.5 cm
and 3.0×1.5 cm acquired digital fibrokeratoma on the toe
and heel as giant one respectively. In Korean dermatologic
literatures, Cho et al.5 reported 1×1×3 cm giant acquired
digital fibrokeratoma (Table 1). In our case, the size of the
tumor was 2.5×1.6×1.4 cm, so we suggest that it is a
proper case of giant acquired digital fibrokeratoma.
The pathophysiology of an acquired digital fibrokeratoma
is unknown. In general, trauma is often thought to be a
predisposing factor, especially on the digits9. In 1985, Kint
et al.2 suggested that the acquired digital fibrokeratoma
resulted from a neoformation of collagen by the fibro-
blasts. Because when comparing with the surrounding
dermis, the tumor was composed of denser fibers than
normal skin and contained more capillaries, more fibro-
blasts and coarser elastic fibers. Nemeth and Penneys10
reported that Factor XIIIa, which was found in fibrovas-
cular tumors, was also found in acquired digital fibro-
keratoma; therefore this factor might play an important
JH Choi, et al
Table 1. Summary of previously reported cases and present case of giant acquired digital fibrokeratoma
Case Sex Age SiteSize Onset Trauma historyTreatmentPrognosis
Cho et al.5
Bron et al.3
Kakurai et al.4
Lt. little toe
Rt. great toe
Lt. great toe
5 years ago
Several years ago
8 years ago
1 year ago
role in the pathogenesis of these tumors. After then, Suh et
al.11 observed the factor XIIIa positive dermal dendrocytes
were increased in acquired digital fibrokeratoma by
immunohistochemical stain and suggested that these cells
were associated with collagen synthesis regulation.
Histopathologic examination shows hyperkeratosis and
irregular acanthosis in epidermis and thick collagen
bundles with dilated capillaries oriented in the direction
of the longitudinal axis in dermis. Kint et al.2 described 3
types of acquired digital fibrokeratoma by clinical and
histopathologic features. Type I acquired digital fibrokera-
toma is a dome-shaped lesion which contains fibroblast
between collagen bundles, fine elastic fibers and numer-
ous capillaries in dermis. Type II is a mainly tall and
hyperkeratotic lesion which contains many more fibro-
blasts and reduced elastic fibers. Type III is a flat to
dome-shaped lesion which is characterized by poorly
cellular and edematous structure and no elastic fibers.
This case showed typical histopathologic findings of
acquired digital fibrokeratoma and was compatible with
The differential diagnosis for acquired digital fibrokera-
toma includes supernumerary digit, cutaneous horn and
neurofibroma. Supernumerary digit is a congenital digital
anomaly, which contains neural bundles in the dermis.
Cutaneous horn is uncommon epidermal tumor which
consists of a column of keratin arising from a wide range
of benign, premalignant or malignant underlying pro-
cesses. Neurofibroma is soft, polypoid skin colored tumor.
On histopathologic examination, the dermis is composed
of loosely spaced spindle cells and wavy collagenous
Simple excision is curative. Usually, there is no recur-
rence after complete surgical excision.
Herein, we report an acquired digital fibrokeratoma which
occurred as a giant one on the left great toe.
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fibrokeratomas. Arch Dermatol 1968;97:120-129.
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heel. Dermatology 2004;208:271-272.
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H. Giant acquired digital fibrokeratoma. J Am Acad Der-
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fibrokeratoma resembling supernumerary digit. Korean J
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al. Two cases of acquired fibrokeratoma occuring on the
prepatellar area and the nail bed. Korean J Dermatol 2003;
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fibroblasts in fibrovascular tumors. J Cutan Pathol 1989;16:
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acquired digital fibrokeratoma: immunohistochemical stain
with anti-factor XIIIa antibody. Korean J Dermatol 1994;32: