Open Journal of Stomatology, 2011, 1, 202-206
doi:10.4236/ojst.2011.14031 Published Online December 2011 (http://www.SciRP.org/journal/ojst/ OJST ).
Published Online December 2011 in SciRes. http://www.scirp.org/journal/OJST
Oral spindle cell lipomas
Patrícia C. Caldeira1, Vanessa F. Bernardes1, Alessandra C. Miranda1, Déborah C. Telles2,
Rodrigo M. R. Batista3, Carlos A . Ribeiro4, Tarc ília A . Silva1
1Department of Oral Pathology and Surgery, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil;
2Hospital of Clinics, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil;
3Association against Cancer of the Midwest Minas Gerais, Divinópolis, Brazil;
4Roberto Alvarenga Institute, Belo Horizonte, Brazil.
Received 9 September 2011; revised 3 November 2011; accepted 24 November 2011.
ABSTRACT
Spindle cell lipoma is an histological type of lipoma
which are rarely found in the oral cavity. We describe
two cases of intraoral spindle cell lipomas. The pa-
tients were men and presented painless slow growing
masses in the left cheek and hard palate, measuring
50 × 30 mm and 23 × 20 mm respectively. Microsco-
pically, both lesions presented a solid proliferation of
mature fat cells intermixed with bundles of connec-
tive tissue. Cells were immunopositive for S100 pro-
tein and CD34 (one case), with low mitotic activity
(Ki-67). The final diagnosis was spindle cell lipomas.
The lesions were excised and no recurrence was no-
ticed after six months. Oral spindle cell lipomas are
unexpected to occur in the oral mucosa, and the main
differential diagnosis is well-differentiated liposar-
coma/atypical lipoma. Lesions are treated with sur-
gical excision and recurrences are rare.
Keywords: Lipoma; Mouth; Soft Tissue Neoplasms
1. INTRODUCTION
Lipomas are the most co mmon soft tissue neoplasms; ne-
vertheless the oral cavity is affected less frequently. Ac-
cording to the microscopic features, lipomas can be clas-
sified as conventional lipomas, fibrolipomas, angiolipo-
mas, myxoid lipomas, sialolipomas, intramuscular lipo-
mas, spindle cell/pleomorphic lipomas (SCPL), myoli-
pomas, or chondroid lipomas [1-3]. Since the first report
of an intra-oral SCPL, 23 new cases have been well do-
cumented [1,2,4-9]. So, we describe clinical and histo-
logical features of two new cases of intra-oral SCPL, and
discuss the characteristics of this rare entity.
2. CASE REPORT
2.1. Case 1
A 38-year-old Caucasian man presented with a painless
oral lesion that had been slowly growing for an indeter-
minate period of time. His medical history was noncom-
tributory, and an extra-oral examination showed no al-
terations. The tumor was located on the left cheek and
was well circumscribed. It was pink-colored, with a smoo-
th, lobulated, and nonulcerated surface. It was sessile
with tender consistency and measured approximately 50
× 30 mm (Figure 1).
2.2. Case 2
A 60-year-old black man presented with a large asymp-
tomatic mass on the center of the hard palate. According
to the patient’s report, the tumor had been slowly increa-
sing in size for 38 years, though it did not interfere with
his mastication or speech. No abnormalities were noticed
from the extra-oral examination. An intra-oral examina-
tion revealed a unique, well-circumscribed, peduncula-
ted, and pink-colored lesion, which was covered by heal-
thy mucosa. The lesion had a firm consistency wh en pal-
pated and measured 23 × 20 mm. The patient was a smok-
er and reported alcohol consumption. Additionally, he was
a user of a partial removable prosthesis, though there was
no history of chronic trauma.
Figure 1. Clinical presentation of case 1: a well-circumscribed
tumor in the left cheek, covered by nonulcerated m u co s a.

P. C. Caldeira et al. / Open Journal of Stomatology 1 (2011) 202-206 203
2.3. Microscopic Findings
In case 1, an incisional biopsy was performed, while in
case 2 the lesion was completely excised. Both proce-
dures were performed under local anesthesia. Specimens
were routinely processed and stained with hematoxylin
and eosin (HE).
Microscopically, both lesions presented a solid prolif-
eration of mature fat cells intermixed with bundles of
connective tissue (Figure 2(a)). Fat cells showed a large
univacuolated cytoplasm with a small, flattened nucleus
in the periphery. Spind le cells with single, vesicular, oval
or fusiform nuclei, as well as a poorly defined cytoplasm,
were noticed to intermix with the fat cells. The underly-
ing connective tissue presented short bundles of collagen
(Figure 2(b)). Moreover, floret-like multinucleated cells
could be observed (Figure 2(c)). Mitotic figures, nuclear
pleomorphism, and hyperchromatism were absent. Vas-
cularization and mast cells were evident, though lym-
phocytes were scarce. Spindle cells in case 1 were im-
munopositive for CD34 (Figure 2(d)), whereas the equi-
valent cells from case 2 were negativ e. Fat cells showed
immunoreactivity for the S100 protein in both cases
(Figure 2(e)). Additionally, Ki-67 immunostaining re-
vealed low mitotic activity (not shown).
The final diagnosis for both cases was spindle cell/
pleomorphic lipoma. A complete excision was perfor-
med in case 1. For both cases, no recurrence was noticed
after six months of follow-up.
3. DISCUSSION
SCPL usually affects the posterior neck, shoulder, and
back regions of middle-aged and elderly men [5]. Occur-
rence in the oral mucosa is uncommon. According to
previous reported cases of oral SCPL and the present re-
port, the most affected intra-oral sites are the tongue and
buccal mucosa, although the floor of the mouth, lip, pal-
ate, and other regions may also be involved [1,2,4-9]. The
male to female ratio is 1.7:1, and the mean age is 56.2
years. Oral SCPL usually presents as a solitary, well-
circumscribed, rubbery, painless, and slow-growing tu-
mor, and it is covered by a healthy mucosa with sizes
ranging from 3 to 50 mm (Ta b le 1 ) [1,2,4-9]. The most
affected intra-oral sites are the buccal mucosa and ton-
gue, although the lip, floor of the mouth, palate, and
other regions may also be involved. The male to female
ratio is 1.36:1, and the mean age is 56 years [1,2,4-9].
Oral SCPL usually presents as a solitary, well-circum-
scribed, rubbery, painless, and slow-growing tumor, and it
is covered by a healthy mucosa with sizes ranging from 3
to 50 mm [1,2 ,4-9].
Figure 2. Microscopic features: (a) solid proliferation of mature fat cells intermixed with bundles
of connective tissue (HE, ×50); (b) Fat cells show a large univacuolated cytoplasm with a small
flattened nucleus in the periphery. Spindle cells have single, vesicular, oval or fusiform nuclei, as
well as a poorly defined cytoplasm. The underlying connective tissue presents short bundles of
collagen (HE, ×100); (c) Floret-like multinucleated cell (arrow) (HE, ×400); (d) spindle cells are
immunopositive for CD34 (streptavidin-biotin, ×400); (e) Fat cells show immunoreactivity for
S100 protein (streptavidin-biotin, ×400).
C
opyright © 2011 SciRes. OJST

P. C. Caldeira et al. / Open Journal of Stomatology 1 (2011) 202-206 204
Table 1. Features of the 27 cases of spindle cell lipoma reported in the oral cavity.
Case number Author/Year of publication Site Gender Age (years) Size (mm)
1 McDaniel et al., 1984 Floor of mouth Female 33 10
2 McDaniel et al., 1984 Tongue Male 52 Not available
3 Christopoulos et al., 1989 Hard palate Male 58 20
4 Lombardi and Odell, 1994 Tongue Female 63 15
5 Levy and Goding, 1989 Floor of mouth Female 74 45
6 Tosios et al., 1995 Cheek Male 55 40
7 Piattelli et al., 1999 Cheek Male 75 20
8 Piattelli et al., 2000 Cheek Male 63 25
9 Said-Al-Naief et al., 2001 Tongue Male 66 30
10 Said-Al-Naief et al., 2001 Tongue Female 53 7
11 Dutt et al., 1999 Tongue Female 42 30
12 Khoo and Lian, 1995 Cheek Male 23 50
13 Atik et al., 2002 Tongue Male 45 20
14 Darling et al., 2002 Alveolar mucosa Male 69 5
15 Piattelli et al., 2005 Floor of mouth Male 50 10
16 Billings et al., 2006 Lower lip Female 55 6
17 Billings et al., 2006 Floor of mouth Female 84 10
18 Billings et al., 2006 Cheek Male 88 10
19 Billings et al., 2006 Tongue Male 45 9
20 Billings et al., 2006 Tongue Male 67 10
21 Billings et al., 2006 Tongue Female 31 3
22 Billings et al., 2006 Tongue Female 75 5
23 Coimbra et al., 2 006 Floor of mouth Female 29 15
24 Imai et al., 2008 Tongue Male 72 15
25 Vecchio et al., 2009 Cheek Male 52 25
26
27 Caldeira et al., 2011 (present cases) Cheek
Hard palate Male Male 38 60 50
23
Generally, clinical differential diagnoses include clas-
sic lipomas, fibromas, fibroepithelial polyps, benign ner-
ve sheath tumors, salivary gland neoplasms, and herni-
ated buccal fat pads [1]. Diagnostic hypotheses of case 1
comprised two categories: mesenchymal tumors of soft
tissues (lipoma, neurilemmoma, neurofibroma) and non-
neoplastic proliferative lesions (fibrous hyperplasia/tra-
umatic fibroma). The most common location for oral
lipomas is the buccal mucosa, and it was also considered
because of the tender consistency of the lesion [4-6].
Considering the clinical aspects the herniated buccal fat
pad, also called “traumatic pseudolipoma”, must be in-
cluded in differential diagnosis [1]. It presents as a ses-
sile or pedunculated mass originated by trauma and is
common in children but may also be present in adults.
When it become epithelialized after trauma is not possi-
ble to distinguish from a true lipoma [1]. Because of
clinical features, other lesions, such as oral dermoid,
epidermoid cysts, and oral lymphoepitelial cysts should
be considered in the differential diagnostic of oral lipo-
mas [5]. In addition, in both cases the neurilemoma and
neurofibroma were included in the differential diagnosis
because of their similar clinical findings. In the case 1,
an incisional biopsy was performed due the extent of the
lesion.
Referring to case 2, the differential diagnosis of the
palatal mass includes the traumatic or irritation fibroma,
benign and malignant salivary gland neoplasms, benign
neural tumors and chronic abscess. These lesions have
many characteristics in common and may appear clini-
cally indistinguishable. Emphasis is placed on the im-
portance of obtaining a thorough, comprehensive health
and dental history and collecting relevant information.
The period of duration of the lesion suggested a benign
lesion. The hypothesis of chronic abscess was excluded
after the dental clinical evaluation and the considered
clinical diagnostic hypotheses were benign mesenchy-
mal neoplasms, including neurilemmoma and neurofi-
broma, as considered in the former case, benign salivary
gland tumor (pleomorphic adenoma), and fibrous hyper-
plasia/traumatic fibroma. Considering the clinical as-
pect and the long period of evolution of the lesion an ex-
cisional biopsy was performed in this case.
Imaging examination using ultrasonography, compu-
ted tomography, and magnetic resonance may aid the
diagnosis of oral lipomas. Unfortunately, there is quite
C
opyright © 2011 SciRes. OJST

P. C. Caldeira et al. / Open Journal of Stomatology 1 (2011) 202-206 205
little information about specific imaging features of oral
SCPL and we could not access images of the present
cases. However, as mention above, SCPL is only a his-
topathological type of a lipoma, which may share imag-
ing features with lipomas overall. On ultrasonography,
oral lipomas are usually hypoechoic. On the computed
tomography images, lesions have a density ranging from
–123 to –83 Hounsfield units, with ill defined margins
and with a characteristic homogeneous appearance with
the same density as subcutaneous fat. Lesions tend to
present high signal intensity on T1-weighted images
with proportional reduction in signal intensity in T2. It
has been stated that imaging by magnetic resonance can
be useful in the delimitation of oral lipomas [10-12].
Microscopically, oral SCPL presents as a well-cir-
cumscribed but rarely encapsulated lesion composed of a
mixture of mature adipocytes and spindle-shaped cells in
a fibrocollagenous and/or myxoid stromal background.
The proportion of lipomatous, spindle cell, and stromal
components may vary from one case to another. Fat cells
are univacuolated with a small peripheral nucleus. Atro-
phic changes in the adipocytes can be noticed, giving
these cells a pseudo-lipoblastic appearance, though true
lipoblasts are absent in SCPL. Spindle cells are usually
uniform in size, shape and staining intensity, and they
show pale-staining, vesicular, oval or compressed nuclei
along with a sparse cytoplasm. The collagenous back-
ground is typically composed of thick, ropey bundles.
Mitosis, cellular pleomorphism, and hyperchromatism are
extremely rare or absent. M ast cells are usually found, and
lymphocytes may be present as well. Moreover, multi-
nucleated floret-like cells can be observed, and vascular-
ity is often inconspicuous [1,2,5]. In the present cases,
only few differences regarding the histopathological fea-
tures could be observed. In case 1, the spindle cell com-
ponent was more exuberant than the adipose component,
while in case 2, both were equally present. Moreover,
multinucleated floret-like cells, myxoid stromal areas,
and some atrophic changes in the fat cells were observed
only in case 2.
The spindle cells usually show positivity for CD34
and vimentin, while the adipocytes express the S100
protein [4,8]. Nevertheless, no reactivity to CD34 could
be observed in case 2. Mast cells can be detected by the
immuno-expression of tryptase [8] and the Ki-67 index
shows a low mitotic activity. Our immunohistochemical
findings are in accordance with previously reported
findings. Additionally, SCPL exhibits cytogenetic aber-
rations of chromosomes 13 and/or 16 [2,9]. Moreover,
some authors have observed that SCPL expresses an-
drogen receptors, pointing to a possible role of sex hor-
mones on its pathogenesis [4]. Nevertheless, this could
not be observed wi t h oral SC PL [2].
The main histopathological differential diagnosis to be
considered is well-differentiated liposarcoma/atypical
lipoma, a rare intra-oral lesion, which may present as a
slow growing and painless mass that is found mainly in
the tongue and cheeks [2]. This distinction, though dif-
ficult, must be made in order to avoid overtreatment and
a long-standing follow-up of the patient [2]. Some fea-
tures, such as the well-circumscribed form; superficial
location; slow growth; absence of lipoblasts; uniform
spindle cells associated with mature, thick, and regular
collagen bundles; sparse vascularity; and the absence of
atypical cells are more likely to be presen t in SCPL than
in well-differentiated liposarcomas/atypical lipomas [1,8,
9]. On the other hand, the most important characteristics
needed to establish the diagnosis of a liposarcoma are
the presence of variations in adipocyte size, atypical and
enlarged adipocyte nuclei, and hyperchromatic stromal
cells [13]. Moreover, spindle cells, if present, may show
nuclear atypia and hypercromasia [13]. An immunohis-
tochemical study is not contributory in this distinction
[13].
Depending on the predominant microscopic compo-
nent of the lesion, SCPL may resemble many other le-
sions. If the spindle cell component is pro minent, fibrol-
ipomas, neurilemmomas, neurofibromas, solitary fibrous
tumors, nodular fasciitis, and malignant histiocytomas
may be considered. Fibrolipomas are less cellular than
SCPL and show large bundles of collagen. In cases
where spindle cells present palisading nuclei, S100 stai-
ning may be useful in distinguishing SCPL from a neu-
rilemmoma. The possibility of a lipomatous neurofibro-
ma or even a neurofibroma can be ruled out by the ab-
sence of wavy nuclei in the spindle cells and their im-
munonegativity for the S100 protein in SCPL [5,6] Soli-
tary fibrous tumors may also show spindle cells that are
positive for CD34; however, fat cells are absent in this
lesion [8,9]. In nodular fasciitis, despite the plump be-
nign spindle cells, there usually is little collagen. Fi-
nally, malignant fibrous histiocytomas can present spin-
dle cells and multinucleated giant cells, though pleo-
morphisms, typical and atypical mitoses, and storiform
arrangements are observed as well [3].
On the other hand, SCPL, with localized spindle cells,
may be similar to conventional lipomas and lipomatous
hemangiopericytomas. In lipomatous hemangiopericy-
toma, the collagenized matrix and adipocytes are associ-
ated with prominent hemangiopericytoma-like vessels
[3]. Finally, a highly myxoid matrix may pose some con-
fusion with myxolipomas and myxoid liposarcomas.
Both lesions lack the wiry collagen; additionally, my-
xolipoma lacks positivity for CD34, whereas myxoid
liposarcoma shows ev ident lipoblastic differentiation [5].
Oral SCPL is treated with surgical excision and recur-
C
opyright © 2011 SciRes. OJST

P. C. Caldeira et al. / Open Journal of Stomatology 1 (2011) 202-206 206
[7] Darling, M., Thompson, I. and Schneider, J. (2002) Spin-
dle cell lipoma of the alveolar mucosa: A case report.
Oral Surgery, Oral Medicine, Oral Pathology, Oral Ra-
diology & Endodontics, 93, 171-173.
doi:10.1067/moe.2002.120520
rences are not expected [7].
4. ACKNOWLEDGEMENTS
This study was supported in part by grants from PRPq-UFMG;
FAPEMIG, CAPES, and CNPq, Brazil. Dr. Silva and Dr. Bernardes are
research fellows of CNPq. [8] Imai, T., Michizawa, M., Shimizu, H., Imai, T., Yama-
moto, N. and Yura, Y. (2008) Bilateral multiple spindle
cell lipomas of the tongue. Oral Medicine, Oral Pathol-
ogy, Oral Radiology & Endodontics, 106, 264-269.
REFERENCES [9] Piattelli, A., Perrotti, V., Fioroni, M. and Rubini, C.
(2005) Spindle cell lipoma of the floor of the mouth:
Report of a case. Auris Nasus Larynx, 32, 205-207.
doi:10.1016/j.anl.2005.01.013
[1] Said-Al-Naief, N., Zahurullah, F.R. and Sciubba, J.J.
(2001) Oral spindle cell lipoma. Annals of Diagnostic
Pathology, 5, 207-215. doi:10.1053/adpa.2001.26973 [10] Chikui, T., Yonetsu, K., Yoshiura, K., Miwa, K., Kanda,
S., Ozeki, S. and Shinohara, M. (1997) Imaging findings
of lipomas in the orofacial region with CT, US, and MRI.
Oral Medicine, Oral Pathology, Oral Radiology & En-
dodontics, 84, 88-95.
[2] Vecchio, G., Amico, P., Caltabiano, R., Colella, G., Lan-
zafame, S. and Magro, G. (2009) Spindle cell/pleomor-
phic lipoma of the oral cavity. Journal of Craniofacial
Surgery, 20, 1992-1994.
doi:10.1097/SCS.0b013e3181bd2dad [11] Bandéca, M.C., De Pádua, J.M., Nadalin, M.R., Ozório,
J.E., Silva-Sousa, Y.T. and Da Cruz, P.D.E. (2007) Oral
soft tissue lipomas: A case series. Journal of the Cana-
dian Dental Association, 73, 431-434.
[3] Barnes, L., Eveson, J., Reichart, P., Sidransky, D., Eds.
(2002) Pathology and genetics of tumours of soft tissue
and bone. World Health Organization Classification of
Tumours, IARC Press, Lyon, 427. [12] Cappabianca, S., Colella, G., Pezzullo, M.G., Russo, A.,
Iaselli, F., Brunese, L. and Rotondo, A. (2008) Lipoma-
tous lesions of the head and neck region: Imaging find-
ings in comparison with histological type. Radiology Me-
dicine, 113, 758-770. doi:10.1007/s11547-008-0258-5
[4] Atik, E., Usta, U. and Aydin, N.E. (2002) Pleomorphic
lipoma of the tongue. Otolaryngol Head Neck Surg, 126,
430-431. doi:10.1067/mhn.2002.123919
[5] Billings, S.D., Henley, J.D., Summerlin, D.J., Vakili, S.
and Tomich, C.E. (2006) Spindle cell lipoma of the oral
cavity. American Journal of Dermatopathology, 28, 28-
31. doi:10.1097/01.dad.0000189615.13641.4b
[13] Nascimento, A.F., McMenamin, M.E. and Fletcher, C.D.
(2002) Liposarcomas/atypical lipomatous tumors of the
oral cavity: A clinicopathologic study of 23 cases. Annals
of Diagnostic Pathology, 6, 83-93.
doi:10.1053/adpa.2002.32375
[6] Coimbra, F., Lopes, J.M., Figueiral, H. and Scully, C.
(2006) Spindle cell lipoma of the floor of the mouth. A
case report. Medicina Oral Patologia Oral y Cirugia
Bucal, 11 , E401-E403.
OJST