Introduction
Dear Editor,
Rhabdomyosarcoma (RMS) is a mesenchymal malignant
neoplasm that exhibits skeletal muscle cells with
varying degrees of differentiation, first described by
Weber in 1854.[] It accounts for <3% of adult softtissue
sarcoma, but is the most common soft-tissue
sarcoma histological subtype and the 4th most common
childhood cancer before the age of 10.[] Oral
RMSs are classified as non-orbital and non-parameningeal
and represent 28% of head and neck RMSs.
[] Dört alt tipi vardır: pleomorfik, alveolar, embriyonal
ve botryoid. It has four subtypes: pleomorphic,
alveolar, embryonal, and botryoid. Embryonal diversity
is the most common and accounts for approximately
49% of all rhabdomyosarcomas.[] Moreover,
the clinical presentation of oral RMS can sometimes
mimic a benign neoplasm or inflammatory process
and, therefore, delay diagnosis.[]
A 46-year-old male patient was admitted to our
clinic with complaints of a mass growing over time in
the right anterior mandibular region, increased mobility
in the teeth in that region, and severe pain. Extraoral
examination revealed swelling in the right anterior
mandible and palpable submandibular lymph
nodes. Intraoral examination of the patient revealed
a mobility, exophytic, lobulated, sessile, and painless
mass in the affected teeth. The lesion was located in
the region of the right anterior teeth, approximately
3×3.5 cm in size, with indistinct borders, hard but
bleeding on palpation (Fig. 1). Intraoral ultrasonographic
examination revealed a highly perfusion hypoechoic
lesion and destruction in the buccal cortical bone. Cone-beam computed tomography showed
complete destruction of the cancellous bone in the
buccal and lingual cortical bone surrounding the affected
teeth and in the relevant region. It revealed
that the teeth in the relevant area appeared "floating"
(Fig. 2). After obtaining the patient's informed
consent, an incisional biopsy was performed and the
sample was sent for pathological examination. Under light microscopic examination, a tumoral lesion that
started under the non-keratinized stratified squamous
epithelium and caused partial ulceration in the
mucosa was observed (Fig. 3a). The tumor consisted
of oval-round eosinophilic cells with occasionally
elongated nuclei and coarse chromatin. Tumor cells
formed solid structures, focal prominent fascicles,
and alveolar spaces (Fig. 3b). Many atypical mitoses
and pleomorphic cells were also observed. While
specific staining was not detected in the histochemical
PAS staining applied for differential diagnosis,
diffuse staining with vimentin, MyoD1 (Fig. 3c), desmin
(Fig. 3d), Bcl-2, and focal staining with Pan CK
and CD99 were observed immunohistochemically.
Melan A, HMB-45, Sox-10, S-100, P40, CK18, Myogenin,
ERG, Kaldesmon, SMA, NF, TLE-1, MUC-4,
and CD57 were negative. In conjunction with this
histological result, it resulted in the embryonal subtype
of RMS being most supportive. The patient was
referred to the oncology service and radiotherapy
and chemotherapy treatment were started before the
operation of the related tumor.
It is always difficult to diagnose RMS due to its variable
clinical presentation and histological diversity.
It usually presents as a painless swelling in the early
stages.[] Other signs and symptoms of oral RMS are
tooth mobility, pain, paresthesia, trismus, and cervical
lymphadenopathy. Most of these symptoms were also
observed in our case.
The classical embryonal variant has a 66% 5-year
survival rate, while the botryoid and well-differentiated
spindle variants have a 5-year survival rate of approximately
90%. Although embryonal prognosis is better
at all ages compared to alveolar subtype, adults tend to
be much worse than children regardless of subtype, as
adult embryonal RMS still has a worse prognosis than
childhood alveolar RMS.[]
A PubMed search for adult RMS of the oral cavity
revealed fewer than 10 case reports published in
the English literature. A few cases of RMS affecting the
oral tissues in adult patients have been presented in the
literature.[,] This report adds to the literature by presenting
a case of embryonal RMS affecting the gingiva,
alveolar mucosa, and right anterior mandible.
RMS treatments include surgery, radiotherapy,
and different chemotherapy regimens. Treatments are
based on tumor stage and clinical manifestations.[]
Long-term treatment sequelae such as facial asymmetry,
abnormalities in tooth formation, jaw hypoplasia,
trismus, and hyposalivation/xerostomia may persist
and significantly alter the patient"s lifestyle.[] Adult
RMS should continue to be treated aggressively, but
new and tailored treatment strategies are needed to
improve long-term outcome.[]
In conclusion, in multivariate analysis, age, histological
subtype, primary site, stage, surgery, radiotherapy,
and local control are the most important factors
determining survival. Clinicians often encounter
cases with facial swelling and pain. We believe that
such swelling should be carefully examined in patients
and the results of treatment should be followed
up regularly. In such cases, high suspicion, early diagnosis,
and multidisciplinary treatment approach are
of great importance.
Fig. 1. Intraoral view and clinical feature of the lesion.
Fig. 2. Cone-beam computed tomography showed complete
destruction of the cancellous bone in the
buccal and lingual cortical bone surrounding the
affected teeth and in the relevant region.
Fig. 3. (a) Light microscopic examination revealed a tumoral lesion that started under the
non-keratinized stratified squamous epithelium and caused partial ulceration of
the mucosa; (b) tumor cells formed solid structures, focal prominent fascicles, and
alveolar spaces; (c) immunohistochemical staining of vimentin and MyoD1; and
(d) immunohistochemical staining of desmin.
