Embryonal Rhabdomyosarcoma (Botryoid Subtype) Affecting the Buccal Mucosa

BOTRROID Embryonal Rhabdomyosarcoma with Uterine Cervix in a Postmenopausal Woman: An Unusual Case Report

Rhabdomyosarcoma (RMS) is one of the most common soft-tissue sarcomas that engage the embryonal skeletal muscle cells as the female reproductive tract. Embryonal RMS (ERMS) is the most prevalent subtype of RMS in the female genital tract. Botryoid RMS is a rapidly growing rare malignancy and a polypoid variant of ERMS that occurs in childhood and constituting approximately 3% of all RMSs among young children and 1% among adolescents and young adults. A 50 year old menopause woman who had been vaginal discharge and bleeding for about 2 years without dysuria, dyspareunia, or postcuital bleeding was informed consent for presenting. A vaginal examination, pathology examination, sonography, magnetic resonance imaging, immunohistochemistry, surgery and radical hysterectomy, radiation therapy, and two sessions of brachytherapy were performed. After 22 months of follow-up, the patient had no evidence of recurrence or any problem in sexual activity. Oncological surgical treatment based on the carcinoma site and adjuvant chemotherapy is helpful for the treatment of RMS. However, applying the standard treatment guidelines is essential, although it is very scarce and difficult.

Embryonal Rhabdomyosarcoma of the Tongue in Adults

(1) Background: Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in the first two decades of life. One third of cases appear in the head and neck, with 60% of these being embryonal type. RMS is extremely rare in adults, comprising only 1% of adult malignancies, and of those, only 3.3% are rhabdomyosarcomas. (2) Case report: A 46 y.o. male presented with a 1 cm exophytic pediculated painless lesion on the dorsum of his tongue, with progressive growth for 3 months. An excisional biopsy revealed an "embryonal rhabdomyosarcoma with fusocellular areas, with negative rearrangement for gen FOXO1A, negative MDM2 (only focal positivity), and positive INI-1". Subsequent contrast-enhanced MRI concluded the presence of a lesion with imprecise margins in the right half-tongue, 15 × 8 × 7 mm (longitudinal × transverse × craniocaudal), compatible with a sarcoma. The patient underwent a partial centrolingual glossectomy followed by reconstruction with a buccinator muscle local flap. After surgery, he received chemotherapy with eight cycles of VAC (vincristine, actinomycin, and cyclophosphamide) protocol. The patient is now disease free after 42 months, with good tongue function. (3) Discussion and conclusions: Embryonal RMS is an extremely rare sarcoma in adults, and the location in the tongue is even more exceptional (only two more similar cases are reported in the literature). The prognosis in adults is significantly poorer than in children. A complete margin-free resection with an adequate chemotherapy protocol is the treatment of choice in cases such as these.

Gingival rhabdomyosarcoma mimicking a non-neoplastic proliferative lesion: A diagnostic challenge

Rhabdomyosarcoma (RMS) is a soft tissue sarcoma that develops from skeletal striated muscle cells. RMSs are exceedingly rare in the oral cavity, particularly in the gingiva. Herein, we reported the clinicopathological and immunohistochemical features of a rare case of RMS in a 30-year-old female presenting clinically as a painful polypoid nodule on the mandibular gingiva. Microscopically, the tumor showed atypical spindle cells with elongated nuclei and eosinophilic cytoplasm arranged in a fascicular pattern. In focal areas, the tumor cells exhibited rhabdomyoblastic differentiation. Immunohistochemistry showed strong positivity for desmin, myogenin (scattered cells), and MyoD1. The patient underwent surgical resection followed by postoperative complementary radio- and chemotherapy. However, the patient had a local recurrence seven months after the initial treatment. She was submitted to a total mandibulectomy associated with adjuvant radiotherapy. However, she died two months after reoperation due to complications secondary to radiation therapy. Because of the rarity in the oral cavity and non-specific signs and symptoms, the clinical diagnosis of RMS is difficult and often overlooked. Therefore, careful histopathological and immunohistochemistry analysis of these tumors is essential to correct diagnosis. Early surgical excision with tumor-free margins and prolonged follow-up are strongly recommended.

DICER1-Mutated Botryoid Fibroepithelial Polyp of the Parotid Duct: Report of the First Case

DICER1, a member of the ribonuclease III family, is involved in the biogenesis of microRNAs and, hence, it influences gene expression regulation. DICER1 germline (associated with the inherited DICER1 syndrome) or somatic mutations have been linked to tumorigenesis in histogenetically diverse benign and malignant neoplasms in different organs including pleuropulmonary blastoma, cystic nephroma, embryonal rhabdomyosarcoma, nasal chondromesenchymal hamartoma, poorly differentiated thyroid carcinoma, thyroblastoma, intracranial sarcoma and gonadal Sertoli-Leydig cell tumors in addition to others. Moreover, rare botryoid (giant) fibroepithelial polyps may harbor this mutation. Herein, we describe the first reported case of a DICER1-mutated botryoid fibroepithelial polyp occurring within the parotid duct of a 65-year-old female who has no other features or family history of the DICER1 syndrome. Based on its distinctive morphology, we tested this lesion specifically for DICER1 mutations and confirmed the presence of a pathogenic DICER1 variant with a low allele frequency, consistent with a somatic mutation.

Intraosseous rhabdomyosarcoma of the maxilla with TFCP2 fusion: A rare aggressive subtype with predilection for the gnathic bones

Rhabdomyosarcomas (RMS) are malignant tumors with skeletal muscle differentiation extremely rare in intraosseous sites. We reported a rare case of an aggressive intraosseous RMS found in the maxilla of a 17-year-old female patient with five months of evolution. Computed tomography revealed a large osteolytic lesion extending from tooth 21 to 27, causing buccal and lingual cortical plate perforation. Microscopically, the lesion showed a proliferation of spindle-shaped cells with elongated nuclei and eosinophilic cytoplasm, arranged in an interlaced fascicle pattern. The nuclei ranged from vesicular with distinct nucleoli to hyperchromatic. A focal component of plump to epithelioid cells with a moderate amount of eosinophilic cytoplasm was seen at the periphery of the tumor. The immunohistochemical analysis revealed positivity for desmin, MyoD1, and myogenin (scattered cells). S-100, SOX10, HMB45, β-catenin, and CD34 were negative. Ki-67 was positive in 30% of tumor cells. Fluorescence in situ hybridization (FISH) analysis showed the presence of a FUS-TFCP2 fusion. The diagnosis was intraosseous RMS with TFCP2 fusion. Surgical excision followed by chemo- and radiotherapy was carried out; however, the patient died of disease nine months after the treatment. Because of the rarity and non-specific signs and symptoms, the clinical diagnosis of intraosseous RMS is difficult and often overlooked. Therefore, careful histopathological evaluation, supported by immunohistochemical and molecular analysis, is essential to correct diagnosis. Early surgical excision with tumor-free margins and prolonged follow-up are strongly recommended.

A large undifferentiated sarcoma of the liver in a 13-year-old girl treated with anatomical resection: a case report and review of the literature

Background

Undifferentiated embryonal sarcoma of the liver (UESL) is a rare liver tumor accounting for 6–13% of primary liver tumors. Accurate preoperative diagnosis is difficult, with a rather high misdiagnosis rate. Herein, we reported a very large UESL treated with anatomical resection. Our case is amongst the largest pediatric UESLs in the literature.

Case presentation

Herein, we report a 13-year-old girl presenting with right upper quadrant abdominal pain, postprandial vomiting, and abdominal distention, in which radiographic imaging demonstrated a huge UESL (28 × 20 × 12 cm). The patient was treated with partial hepatectomy and the 5 kg tumor was removed. The patient was discharged in good condition, with no significant complaints in her follow-up.

Conclusions

Although different treatment strategies have been reported for UESL cases, anatomical resection is still the main treatment approach, especially for large tumors.

Primary intraosseous malignant peripheral nerve sheath tumor of the mandible: An unusual presentation mimicking a benign lesion

The malignant peripheral nerve sheath tumor (MPNST) is a rare, aggressive malignant tumor that usually develops in the context of neurofibromatosis type 1. In the oral cavity, these tumors are excelling rare, especially in intraosseous sites. Herein, we report an unusual presentation of intraosseous MPNST affecting the mandible posterior region in a 28-year-old male without neurofibromatosis type 1 discovered as an incidental find on imaging exam. CT scan evaluation showed a solitary, well-defined, round hypodense lesion in the posterior mandibular region extending from tooth 45 to 46. Microscopic evaluation showed a tumor composed of atypical spindle-shaped cells arranged in fascicles and a storiform pattern. Tumor cells were positive for S-100 protein. Epithelial membrane antigen (EMA), pan-cytokeratin AE1/AE3, desmin, alpha-smooth muscle actin (α-SMA), HMB-45, MART-1, MUC4, and CD56 were negative. The diagnosis was low-grade MPNST. The patient underwent wide surgical resection of the tumor. After three years of follow-up, the patient remained with no evidence of recurrence or metastatic disease. When an intraosseous neurogenic tumor is suspected based on radiological characteristics, despite the apparent benign nature, an incisional biopsy is mandatory to rule out malignancy before treatment planning to avoid inadequate conservative treatment.

A recurrent leiomyosarcoma of the buccal mucosa: An immunohistochemistry study and literature review

Leiomyosarcoma is a rare type of cancer that affects smooth muscle tissue. Leiomyosarcomas are exceedingly rare in the oral cavity, particularly in the buccal mucosa. The diagnosis is challenging due to non-specific clinical features and significant overlap of morphological findings with several spindle cell tumors. We reported the clinicopathological and immunohistochemical features of a rare recurrent case of leiomyosarcoma in a 73-year-old female presenting clinically as a painful nodule on the posterior right buccal mucosa. Microscopically, the lesion showed atypical spindle cells arranged in a fascicular pattern and frequent mitotic figures. Immunohistochemistry showed strong positivity for vimentin, α-SMA, HHF35, h-caldesmon, and focal positivity for desmin. CD34 highlighted numerous blood vessels distributed throughout all tumor stroma. S-100 protein, myogenin, and pan-cytokeratin (AE1/AE3) were negative. Surgical excision followed by chemotherapy was carried out, and no recurrence was observed after 1 year of follow-up. Careful histopathological and immunohistochemistry analysis of these lesions is essential to ensure a correct diagnosis. Early surgical excision with tumor-free margins and prolonged follow-up is strongly recommended.

Oral focal mucinosis: A multi-institutional study and literature review

BACKGROUND

Oral focal mucinosis (OFM) is a rare benign condition of unknown etiology, considered the oral counterpart of cutaneous focal mucinosis. We report the clinicopathologic features of 21 cases of OFM in conjunction with a review of the literature.

METHODS

Clinical data were collected from the records of five oral and maxillofacial pathology services. All cases were evaluated by hematoxylin and eosin staining, histochemistry, and immunohistochemistry (vimentin, S-100, α-SMA, CD34, and mast cell).

RESULTS

The series comprised 14 females (66.7%) and seven males (33.3%), with a mean age of 48.2 ± 20.7 years (range: 8-77 years) and a 2:1 female-to-male ratio. Most of the lesions affected the gingiva (n = 6, 28.6%) and presented clinically as asymptomatic sessile or pedunculated nodules with fibrous or hyperplasic appearance. All cases were negative for S-100 protein, CD34, and α-SMA and positive for Alcian blue staining. Conservative surgical excision was the treatment in all cases, and there was only one recurrence.

CONCLUSION

OFM is a rare benign disorder that is often clinically misdiagnosed as reactive lesions or benign proliferative processes. Dermatologists and pathologists should consider OFM in the differential diagnosis of soft tissue lesions in the oral cavity, mainly located in the gingiva.