Multifocal adult rhabdomyoma of the head and neck: a case report and literature review

Rhabdomyoma of the Oral Cavity Mimicking Reactive Lesions: A Case Report and Review of the Literature

Extracardiac rhabdomyoma is a tumor that rarely occurs in head and neck region. Adult and fetal types of extracardiac rhabdomyoma are diagnosed only by histopathological examination. In the oral cavity, this lesion usually affects the mouth floor and tongue. Despite the low incidence, adult rhabdomyoma should be considered in the differential diagnosis of oral cavity lesions, and histopathological evaluation might be helpful for the final diagnosis. This study aims to report a rare case of rhabdomyoma mimicking reactive lesions and review the literature. A 34-year-old male was referred to the pathology department with a yellowish sessile lesion in the labial maxillary vestibule. During an excisional biopsy, a mass of unencapsulated soft tissue beneath the vestibular mucosa was observed. The yellowish color in clinical features has led to lipoma as the initial clinical diagnosis. The histological examination exhibited an encapsulated, well-circumscribed benign neoplasm composed of multiple lobules of large polygonal cells with prominent abundant granular eosinophilic cytoplasm. No cellular atypia was observed. Diagnosis of the adult type of rhabdomyoma was made by collective agreement. Rhabdomyoma can be mistaken for other reactive lesions and may resemble their appearance.

Oral Adult Rhabdomyoma

This report describes a case of an adult rhabdomyoma (ARM) occurring in the oral cavity. A 47-year-old man was referred for the diagnosis of a painless, well-circumscribed, submucous nodule located on the floor of the mouth, measuring approximately 6.0 cm in length. Computed tomography revealed a well-defined, solid, and hypodense mass. A benign salivary gland or mesenchymal tumor were the main diagnostic hypotheses. Under local anesthesia, the patient underwent surgical excision. Microscopically, the tumor comprised large polygonal well-defined cells with abundant, eosinophilic granular cytoplasm with cross striations. No atypia or mitosis was observed. The cells were positive for muscle-specific actin, desmin, and sarcomeric alpha-actin. Based on these features, a diagnosis of ARM was established. No recurrence was observed after 48 months. Although rare, ARM should be considered in the differential diagnosis of oral submucosal nodules, especially those located on the floor of the mouth.

Multifocal adult rhabdomyoma of the head and neck: case report and systematic review of the literature

Adult-type rhabdomyoma (ARM) is the most frequent extracardiac subtype of rhabdomyoma. In very rare instances ARM presents as multiple cervical lesions, an entity known as multifocal ARM. The aim of this study was to review the clinical characteristics and the best therapeutic options for multifocal ARM. The case of a 73-year-old patient recently diagnosed with multifocal ARM and managed in our institution is reported, followed by a systematic review of the literature. The review was conducted using the PubMed, Scopus, and Google Scholar databases, according to the PRISMA guidelines. All case reports and case series related to multifocal ARM written in English or French were included. A total of 29 cases were included in the qualitative analysis. Mean age at presentation was 65.0 years and the male to female ratio was 13.5:1. Dysphagia was the most common presenting symptom. ARM was most frequently found in the submandibular spaces. In conclusion, multifocal ARM are benign tumours with a predilection for the head and neck region. They become symptomatic with gradual compression of the adjacent structures. No cases of malignant transformation were reported in the literature. We suggest a 'watchful wait' approach for small asymptomatic tumours and excision of large symptomatic ones.

Actin isoform expression patterns in adult extracardiac and cardiac rhabdomyomas indicate a different cell of origin

Rhabdomyomas are rare striated muscle-type tumors arising in the heart or in soft tissues. Using a monoclonal antibody specific for the cardiac isoform of α-actin (α-cardiac actin, α-CAA), differential expression patterns in striated muscle tissues were reported previously. The purpose of the present study was to determine whether the α-actin isoform specificity is maintained in rhabdomyomas according to their origin, comparing extracardiac to cardiac rhabdomyomas. We immunohistochemically investigated adult extracardiac (pharyngeal) rhabdomyomas (n = 4) and cardiac rhabdomyomas (n = 7) employing isoform-specific monoclonal antibodies. The extracardiac rhabdomyomas revealed only a few scattered α-CAA-positive tumor cells (antibody cAc1-20.42) while the cardiac rhabdomyomas exhibited abundant expression of α-CAA, indicating a close relatedness to cardiac muscle fibers. The α-skeletal actin (α-SKA) specific monoclonal antibody (3B3) produced the reverse results. General sarcomeric antibodies (HHF35 and Alpha Sr-1) displayed strong positivity in all rhabdomyomas studied. Alpha-smooth muscle actin (α-SMA) was negative or heterogeneously positive in extracardiac and cardiac rhabdomyomas. Our results suggest that despite similar morphology, the intrinsic differential alpha-actin isoform specificity of mature skeletal vs. cardiac muscle is maintained in extracardiac and cardiac rhabdomyomas. Thus, adult extracardiac rhabdomyomas differentiate towards mature skeletal muscle although they may exhibit centrally placed nuclei like cardiac muscle cells, while cardiac rhabdomyomas reflect true cardiac muscle differentiation. Our findings appear to indicate a different biological nature of cardiac and extracardiac rhabdomyomas, probably related to a different cell of origin. To our knowledge, this is the first report suggesting a derivation of extracardiac and cardiac rhabdomyomas from skeletal and cardiac muscle cells, respectively.

MRI Verification of a Case of Huge Infantile Rhabdomyoma

Introduction:

Cardiac rhabdomyoma is type of benign myocardial tumor that is the most common fetal cardiac tumor. Cardiac rhabdomyomas are usually detected before birth or during the first year of life. They account for over 60% of all primary cardiac tumors.

Case report:

A 6 month old child with coughing and obstruction in breathing, was hospitalized in the Pediatric Clinic in UCCK, Pristine. The difficulty of breathing was heard and the pathological noise of the heart was noticed from the pediatrician. In the echo of the heart at the posterior and apico-lateral part of the left ventricle a tumoral mass was presented with the dimensions of 56 × 54 mm that forwarded the contractions of the left ventricle, the mass involved also the left ventricle wall and was not vascularized. The right ventricle was deformed and with the shifting of the SIV on the right the contractility was preserved. Aorta, the left arch and AP were normal with laminar circulation. The pericard was presented free. Radiography of thoracic organs was made; it resulted on cardiomegaly and significant bronchovascular drawing. It was completed with an MRI and it resulted on: Cardiomegaly due to large tumoral mass lesion (60×34 mm) involving lateral wall of left ventricle. It was isointense to the muscle on T1W images, markedly hyperintense on T2W images. There were a few septa or bant like hypointensities within lesion. On postcontrast study it showed avid enhancement. The left ventricle volume was decreased. Mild pericardial effusion was also noted. Surgical intervention was performed and it resulted on the histopathological aspect as a huge infantile rhadbomyoma.

Conclusion:

In most cases no treatment is required and these lesions regress spontaneously. Patients with left ventricular outflow tract obstruction or refractory arrhythmias respond well to surgical excision. Rhabdomyomas are frequently diagnosed by means of fetal echocardiography during the prenatal period.

Intraoral adult rhabdomyoma: a case report

A case of adult rhabdomyoma is reported. The lesion is a rare benign tumor of skeletal muscle origin which occurs predominantly in the head and neck region. In the present case, the clinical diagnosis favored a benign salivary gland tumor. Histologically, the tumor was composed of large round, oval, and polygonal cells of varying size with abundant pale, eosinophilic, fine, granular cytoplasm with peripherally located nuclei. Immunohistochemically, the lesion was positive for muscle-specific actin, smooth muscle actin, desmin, S100 protein, and Masson's trichrome. Electron microscopic examination confirmed the presence of numerous myofibrils. The lesion was treated by surgical resection. The clinical, histological, immunohistochemical, and ultrastructural features are discussed in this study.

Multifocal adult rhabdomyoma of the head and neck manifestation in 7 locations and review of the literature

Background. Adult rhabdomyoma is a rare benign tumour with the differentiation of striated muscle tissue, which mainly occurs in the head and neck region. Twenty-six cases of multifocal adult rhabdomyoma are documented in the literature. Method. We report a 55-year-old male with simultaneous diagnosis of 7 adult rhabdomyomas and review the literature of multifocal adult rhabdomyoma. Result. Review of the literature revealed 26 cases of multifocal adult rhabdomyoma, of which only 7 presented with more than 2 lesions. Mean age at diagnosis was 65 years with a male to female ratio of 5.5 : 1. Common localizations were the parapharyngeal space (36%), larynx (15%), submandibular (14%), paratracheal region (12%), tongue (11%), and floor of mouth (9%). Besides the known radiological features of adult rhabdomyoma, our case showed FDG-uptake in (18) F-FDG PET/CT. Conclusion. This is the first case of multifocal adult rhabdomyoma published, with as many as 7 simultaneous adult rhabdomyomas of the head and neck.

Rhabdomyomas of the submandibular and sublingual glands

Rhabdomyomas are rare benign mesenchymal tumors distinguished in cardiac and extracardiac forms. Extracardiac rhabdomyomas are classified as adult type, fetal type, and the genital type. Adult extracardiac rhabdomyomas are mostly found in the head and neck and usually present a slow growth. We report a case of a patient with a manifestation in the submandibular and sublingual glands.

Mediastinal rhabdomyoma: case report and review of the literature

Rhabdomyomas are benign tumors in which at least some cells are differentiated as skeletal muscle cells with cytoplasmic cross-striations. Extracardiac adult rhabdomyoma is an extremely uncommon benign neoplasm that usually involves the head and neck region. Rare cases have been reported to involve other sites of the body including mediastinum. We report the fourth case of mediastinal adult rhabdomyoma.