Extracardiac Rhabdomyoma Research Articles

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.

Molecular assessment of paratesticular rhabdomyomas demonstrates recurrent findings, including a novel H3C2 p.K37I mutation

Rhabdomyomas are benign tumors with skeletal muscle differentiation that are broadly divided into cardiac and extracardiac types. The latter demonstrate a predilection for head and neck and genital locations and are further subclassified into adult-type rhabdomyoma (ATRM), fetal-type rhabdomyoma (FTRM) and genital rhabdomyoma (GRM). Most extracardiac rhabdomyomas that arise in paratesticular tissues have a somewhat distinctive morphology and have been termed sclerosing rhabdomyomas (SRM). Therefore, we hypothesized that these tumors may harbor recurrent genetic alterations. In this study, we assessed 15 paratesticular rhabdomyomas (11 initially classified as SRM, 2 cellular FTRM and 2 ATRM) using massively parallel DNA and RNA sequencing. Five of 14 successfully sequenced cases harbored a novel H3C2 p.K37I mutation (4 SRM and 1 ATRM). This mutation replaced a highly conserved lysine residue that is a target for epigenetic modifications and plays a role in regulation of DNA replication. Moreover, 4 tumors (2 cellular FTRM, 1 case initially diagnosed as SRM and 1 ATRM) had complex copy number profiles characterized by numerous chromosome-level and arm-level copy number gains, consistent with a ploidy shift. Rereview of the SRM with copy number gains demonstrated that it was significantly more cellular and had a more prominent fascicular architecture than the rest of the SRMs included in this series. Therefore, it was retrospectively reclassified as a cellular FTRM. In conclusion, this study demonstrated that paratesticular rhabdomyomas harbor recurrent somatic H3C2 p.K37I mutations and ploidy shifts.

Pediatric Fetal Rhabdomyoma Representing as Acute Mastoiditis: A Case Report and Literature Review

Rhabdomyomas are rare benign tumors. Most extracardiac rhabdomyomas are found in the head and neck region, especially in the pharynx and larynx. Herein, we have described the case of a 1-year-old boy presenting with recurrent otorrhea and postauricular swelling. His symptoms were due to a mass that was histologically diagnosed as fetal rhabdomyoma (FR). Here, we report the first case of FR in the postauricular area. Clinicians should keep in mind the possibility of FR if a child presents with external auditory canal mass associated with recurrent otorrhea and signs of mastoiditis.

Rabdomioma del espacio parafaríngeo

Rhabdomyoma is a benign tumor that comes from skeletal tissue, it is classified as cardiac and extracardiac according to the location. Extracardiac rhabdomyomas most frequently originate in the head and neck at the larynx and pharynx, being the parapharyngeal space an exceptional location. We present the clinical case of an 86-year-old man asymptomatic patient with a laterocervical mass with years of evolution, that has increased its size progressively, with dysphagia and dyspnea on exertion in the last years. CT and MRI were requested, which provided dimensions, location at the parapharyngeal space, as well as signs of benignity. The FNA results indicated that it was a mesenchymal tumor. After cervicotomy and histological study, the diagnosis of parapharyngeal space rhabdomyoma was confirmed. We conducted a bibliographic review of this extremely rare benign tumor at the head and neck level.

Rhabdomyoma of the tongue base

<p class="abstract">Extracardiac rhabdomyoma is a very rare condition with potentially multifocal manifestations including the head and neck region. We present a case of an 81-year-old patient who presented as a medical emergency because of ambiguous, progressive throat pain and dysphagia. After diagnostic work up including magnetic resonance (MR) scan and biopsy a rhabdomyoma of the tongue base was diagnosed. The tumor was completely excised by transoral laser microsurgery and the patient’s symptoms vanished. This case report is described in context of the current literature with a discussion of diagnostic steps and treatment options of rhabdomyoma in the head and neck region. Rhabdomyoma is a rare, but nevertheless relevant differential diagnosis of head and neck tumors.</p>

An Unusual Cause of Dysphagia: Hypopharyngeal Rhabdomyoma

Extra-cardiac rhabdomyomas are rare benign soft tissue tumors accounting for 2% of sk eletal muscle neoplasms. Oral cavity and pharynx are the most common sites for rhabdomyomas origina ting from the head and neck region. The presenting symptom for head and neck rhabdomyomas may change according to tumor size and location. The main treatment modality is total surgical excision.In this study, we aimed to report an adult hypopharyngeal rhabdomyoma case presenting with dysphagia and globus sensation and to discuss head and neck extra-cardiac rhabdomyomas reported in the literature.

Genital Rhabdomyoma of the Lower Female Genital Tract: A Study of 12 Cases With Molecular Cytogenetic Findings.

Of the subtypes of extracardiac rhabdomyoma, genital rhabdomyoma is most uncommon and is occasionally classified as fetal rhabdomyoma due to morphologic similarities. In contrast to other forms of rhabdomyoma, the genetic alterations of genital rhabdomyoma are unknown. The clinical and pathologic findings in 12 cases were reviewed and 2 cases were processed for whole genome copy number analysis by single nucleotide polymorphism microarray. Twelve patients ranged in age from 43 to 65 yr (mean: 50.2 yr). Nine tumors arose in the vagina and 3 in the cervix, with their greatest dimension spanning 0.9 to 1.7 cm (mean: 1.4 cm). Follow-up was available for 7 patients and none had evidence of recurrence (67-263 mo, mean: 153.7 mo). No somatic copy number alterations, particularly involving genes in Hedgehog signaling, were identified by microarray. Although genital rhabdomyoma has sufficiently unique clinicopathologic characteristics including age of onset and organs of involvement to distinguish it from fetal rhabdomyoma, the genetic mechanisms underlying its development are unclear given the lack of copy number variation and loss of heterozygosity by single nucleotide polymorphism microarray.

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.

Extra-Cardiac Fetal Rhabdomyoma of Dorsum Of Foot: A Rare Case Report

Extracardiac fetal rhabdomyoma is a rare tumor occurs almost exclusively in children under the age of 10 years with a predilection for the head and neck region and chest wall. It can occur in other sites also. However it is very rare in dorsum of foot. Rhabdomyoma accounts for less than 2% of all striated muscle tumors. Differentiation from Embryonal Rhabdomyosarcoma(ERMS) is very important to avoid aggressive treatment and its consequences. We have reported this case of extracardiac fetal rhabdomyoma of dorsum of foot in an eleven month old male child because of rarity of location which was surgically resected. Histopathology and immunohistochemistry confirmed the diagnosis of extra cardiac fetal rhabdomyoma. DOI: 10.21276/APALM.2017.1045

A congenital case of intermediate-type fetal rhabdomyoma in an Ardi goat kid

A 5-year-old pregnant Ardi goat presented with dystocia of 36 h duration. Vaginal examination showed normal fetal presentation; however, a large neck mass prevented vaginal delivery and cesarean section was performed to deliver the stillborn kid. A well-circumscribed, poorly lobulated subcutaneous mass (12.5 cm in diameter) was found on the ventral lateral aspect of the neck. The cut surface was fleshy and tan to pale white in appearance. Histologically, the tumor exhibited moderate to high cellularity and consisted of elongate to ribbon-like myotubes, with many showing differentiation into larger cells having cross-striations. Nuclei were often multiple (2–5+) and peripheral. Neoplastic cells lacked anaplasia and had a low mitotic index (<1 mitosis per 10 fields of 400× magnification). The neoplastic cells had diffuse myoglobin and multifocal desmin immunostaining. The clinical and histopathological features were consistent with a diagnosis of intermediate-type fetal rhabdomyoma, a rare tumor reported in the human literature. This is to our knowledge the first report of intermediate-type fetal rhabdomyoma in the veterinary literature and the first report of dystocia secondary to a congenital, extracardiac rhabdomyoma.

Fetal Rhabdomyoma of the Right Tonsil with Polyp-Like Appearance.

Skeletal muscle neoplasms, in contrast to other groups of tumors, are almost malignant. The benign variant, rhabdomyoma, is distinctly rare. Rhabdomyomas can be classified generally into two types: cardiac and extracardiac. Extracardiac rhabdomyoma can be further divided into three subtypes: adult, fetal, and genital type. Adult rhabdomyoma is the most common subtype of rhabdomyoma even though it remains relatively rare. Fetal rhabdomyomas are less common than the adult type. In this paper we report a rare case of a fetal rhabdomyoma with polyp-like appearance originating from right tonsil. Punch biopsy and then right tonsillectomy were performed for complete excision. There was no obvious recurrence.

Paratesticular Rhabdomyoma

Extracardiac rhabdomyomas, which currently are classified into fetal, adult, and genital types, are rare. We have identified 7 cases of a distinct morphologic variant of rhabdomyoma that affects mainly young men in the paratesticular region, seen in consultation between 2001 and 2011. The 7 male patients were adults (median age 24 y) and presented with tumors in paratesticular soft tissue (4 left-sided, 3 right-sided). Grossly, the median tumor size was 4.5 cm (range, 2.0 to 12 cm), and lesions were well circumscribed with a uniform tan-white cut surface. Microscopically, these rhabdomyomas were characterized by bundles of large well-differentiated skeletal muscle cells with copious eosinophilic cytoplasm that were variably round, polygonal, and occasionally strap shaped. The tumor cells were set in a dense hyalinized collagenous stroma, often with adjacent prominent lymphoplasmacytic aggregates. Tumor cells had round, occasionally vesicular, nuclei (sometimes binucleate or multinucleate) with small or inconspicuous nucleoli. All tumors lacked nuclear atypia and necrosis. Mitotic activity was virtually absent, although 1 tumor showed a count of 1 per 50 HPF. All tumors were diffusely positive for desmin, 4/4 were diffusely positive for fast myosin, and 1/1 examined was positive for myf-4. All patients were treated by local excision (5 with positive margins). Four patients with known follow-up data had no evidence of tumor recurrence or disease progression (median follow-up time 8.5 mo). The clinical course as determined thus far is benign, similar to other types of rhabdomyoma. However, this rare paratesticular subset of rhabdomyomas appears to be morphologically distinct from rhabdomyomas at other locations and appears to represent a separate variant.

Rhabdomyoma of larynx – A diagnaostic dilemma

IntroductionRhabdomyomas of the head and neck are unusual. Extracardiac rhabdomyoma is a rare benign tumor of striated muscle origin that is found in adults and children. We report a case of rhabdomyoma of the larynx, which presented a diagnostic dilemma. Case reportWe report an uncommon case of a 50-year-old man, who presented with change in voice for two years. Endoscopic examination of the larynx revealed a smooth mass covered by intact mucosa involving the right aryepiglottic fold and a false vocal cord with restricted right vocal cord mobility. Biopsy from the lesion revealed a diagnosis of squamous cell carcinoma. The patient underwent total laryngectomy. To our surprise, histologic examination and immunohistochemical diagnosis proved it to be rhabdomyoma of the adult type with no evidence of malignancy. DiscussionMost extracardiac rhabdomyomas arise from the pharyngeal constrictor muscles, the floor of the mouth, or the base of the tongue. Rarely, rhabdomyomas may arise from the larynx. Histologic and immunohistochemical analysis is essential for diagnosis. Treatment of rhabdomyoma consists primarily of complete excision with preservation of the surrounding tissues. ConclusionOur case demonstrates various differential diagnoses possible in laryngeal neoplasms. It also shows that immunocytochemistry plays an important role in differential diagnosis.

A 68‐Year Old Man with A Cerebellopontine Angle Tumor

We report on a 68-year-old male with a cerebellopontine angle tumor manifesting at the 8th cranial nerve and presenting histopathological features of a rhabdomyoma. A literature review revealed four reports of intracranial nerve rhabdomyoma, all of adult type and including one manifestation at the vestibular nerve. We present the first case of a fetal type extracardiac rhabdomyoma manifesting at a cranial nerve. Although rare, rhabdomyomas must be considered in the differential diagnosis of vestibular schwannomas.

Case report: adult rhabdomyoma of the lip

The patient was a 53-year-old male, on disability pension with a background of asthma and smoking, who presented with a 5 month history of a slowly enlarging right lower lip lesion. There were no other associated symptoms. On examination, there was a 5 mm submucosal nodule located on the buccal region of the right lower lip. Wedge resection of the lesion was performed, and tissue was sent for histopathological examination. Macroscopically, the specimen consisted of a wedge excision of lip, composed of tan mucosa with underlying soft tissue measuring 13 × 10 mm with a depth of 2 mm. There was no evidence of ulceration. On cut surface, there was a small submucosal nodule with a tan and lobulated appearance. Microscopically, the lesion was composed of solid sheets of ectopic skeletal muscle extending to the epidermis. The lesional cells had large, polygonal eosino-philic cells with granular cytoplasm and small peripheral nuclei. There was no significant nuclear atypia, mitotic activity, or necrosis seen. Immunohistologically, the lesional cells were strongly positive for myogenic markers such as desmin and actin. The le-sional cells were negative for S100. The differential diagnoses that need to be considered are granular cell tumour, hibernoma, and oncocytoma. Rhabdomyomas are uncommon tumours of skeletal muscle differentiation and are classified into cardiac or extracardiac in location. Extracardiac rhabdomyomas comprise 2% of all tumours of skeletal muscle differentiation and are subclassified into adult and fetal types. Adult type rhabdomyomas most commonly present in the oral cavity or superficial soft tissue of the head and neck region and 20% are multifocal. Although the tumour is benign, local recurrences have been reported.

Unusual Presentation of Extracardiac Fetal Rhabdomyoma of the Larynx in a Pediatric Patient with Tuberous Sclerosis

Tuberous sclerosis (TSC) is an autosomal-dominant genetic disease characterized by a spectrum of pathologic manifestations involving skin, brain, kidney, and heart. These manifestations include neuroectodermal, mesodermal, and skin lesions as well as a variety of associated tumors and hamartomas. We report an 11-year-old male with previously diagnosed TSC who presented with a laryngeal mass shown on histology to be fetal cellular rhabdomyoma. Cardiac rhabdomyomas are common in TSC patients, but to our knowledge, the association between TSC and extracardiac rhabdomyomas has not been previously reported.

Voluminous Extracardiac Adult Rhabdomyoma of the Neck: A Case Presentation

Introduction. Rhabdomyomas of the head and neck are exceptionally rare benign mesenchymal tumors. Rare cases have been reported to involve other sites of the body including the head and neck regions. Case Presentation. We report a case of voluminous extracardiac adult rhabdomyoma affecting adult patients and initially seen as slowly growing, indolent neoplasms. The patient is a seventy-year old male Italian patient. Conclusion. Adult extracardiac rhabdomyoma is a rare benign tumor that may present with symptoms that vary from aerodigestive tract obstruction to remaining asymptomatic for many years. Although histology is very characteristic, several differential diagnoses have to be considered. To our knowledge, this is the first case of voluminous adult-type symptomless rhabdomyoma.

Genital rhabdomyoma of the urethra in an infant girl

Extracardiac rhabdomyomas are rare benign entities that usually occur in the head and neck region. Although genital rhabdomyoma is known to occur in the lower genital tract of young and middle-aged women, involvement of the anatomically adjacent urethra by rhabdomyoma is exceedingly rare. We present a case of genital rhabdomyoma arising from the urethra of an infant girl. The tumor was characterized by the submucosal presence of mature-appearing rhabdomyoblastic cells containing conspicuous cross-striations, with the cells set in a collagenous stroma. Necrosis and mitoses were absent. Skeletal muscle differentiation of the tumor cells was supported by positive immunohistochemical staining for desmin and myogenin. To our knowledge, this is the first case of urethral genital-type rhabdomyoma in a child.

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.

Adult rhabdomyoma in the parapharyngeal space: report of 2 cases and review of the literature

Rhabdomyomas are rare benign mesenchymal tumors with skeletal muscle differentiation. They are less commonly encountered than are their malignant counterparts, rhabdomyosarcomas. Rhabdomyomas fall into 2 general categories: cardiac and extracardiac types. Extracardiac rhabdomyomas are among the rarest tumors in humans and can be subclassified as fetal, juvenile, and adult types depending on the individual tumor's degree of differentiation by light microscopy. Adult extracardiac rhabdomyoma has a strong predilection for occurrence in the head and neck, mainly in the area of larynx and pharynx. In this article, 2 cases of parapharyngeal rhabdomyoma are reported together with a review of the world literature.