Primary pineal alveolar rhabdomyosarcoma in an adult patient: a case report and literature review

BACKGROUND

The rarity of adult primary cerebral rhabdomyosarcoma (PCRMS) cases has necessitated the adoption of pediatric rhabdomyosarcoma (RMS) therapeutic protocols, highlighting a critical need for expanded treatment experiences to enhance prognoses.

CASE PRESENTATION

A 21-year-old female presented to our facility with a 20-day history of persistent headache, nausea, and vomiting, along with mild upward gaze palsy for the past 5 to 7 days. A brain magnetic resonance imaging (MRI) revealed a mass in the pineal region, extending into the third ventricle, measuring approximately 2.5 × 2.0 × 3.0 cm. The lesion exhibited mild irregular lobulation and heterogeneous enhancement. Intraoperatively, it displayed characteristics similar to high-grade gliomas, including a grayish appearance, abundant vasculature, firm texture, and indistinct margins adjacent to the bilateral thalamus. Pathology confirmed alveolar PCRMS with FOXO1 gene rearrangement. Whole-body imaging following pathological diagnosis showed no evidence of skull base infiltration or extracranial metastasis. Despite comprehensive multimodal treatment, including surgery, stereotactic radiotherapy, and chemotherapy, tumor recurrence occurred three months after initial surgery, and the patient unfortunately succumbed to the disease eight months after her initial diagnosis.

CONCLUSIONS

Alveolar PCRMS in the pineal region, a distinct subtype of RMS, is exceptionally rare and typically associated with a bleak prognosis, suggesting unique tumor biology. A multidisciplinary and aggressive management approach is crucial. Further research into the molecular makeup of RMS in adults may pave the way for more effective, tailored treatments for this aggressive disease.

Adult Primary Pineal Alveolar Rhabdomyosarcoma with FOXO1 Gene Rearrangement and OLIG2 Expression: A Rare Case Report and Literature Review

Alveolar rhabdomyosarcoma is a common malignant soft tissue tumor in child and adolescents. Intracranial alveolar rhabdomyosarcoma in adults is rare, especially in the pineal region. We present a case of primary alveolar rhabdomyosarcoma of the pineal gland in a 36-year-old Chinese male with a chief complaint of dizziness, headache and a loss of balance when walking. Imaging identified a space-occupying mass in the pineal region with obstructive hydrocephalus. An endoscopic-assisted pineal mass resection was performed. Pathology revealed a solid, sheet-like growth of medium-sized, round or oval cells with map-like necrosis and some rhabdomyoblasts. The tumor cells were diffusely positive for desmin, myogenin, MyoD1, ALK, and OLIG2. Fluorescence in situ hybridization (FISH) detected FOXO1 gene rearrangement. This rare case is presented to expand the knowledge of pineal gland tumors and alert us to pay attention to the differential diagnosis of OLIG2-positive round-cell tumors of the central nervous system.

Primary Brain Rhabdomyosarcoma Causing Extracranial Metastases: Case Report with Narrative Review of Atypical Presentations and Their Diagnostic Challenges

BACKGROUND

Rhabdomyosarcoma is a rare malignant tumor originating from striated muscle cells. It accounts for only 3% of all soft tissue sarcomas in adults, and its metastases can also reach the central nervous system. Only sporadic cases of primary brain rhabdomyosarcoma (PBRMS) have been reported so far.

CASE DESCRIPTION

We discuss the atypical presentation and diagnostic challenge of PBRMS in a 65-year-old man. He presented with a 3-day history of progressive right hemiparesis caused by an unspecific left frontoparietal heterogeneously enhancing lesion. Total body computed tomography and positron emission tomography scans performed at baseline did not reveal other secondarisms. The patient underwent radical excision of the lesion, which allowed to establish the diagnosis, with immunohistochemical staining positive for desmin and myogenin. Stereotactic radiotherapy guaranteed local disease control; nonetheless, the patient also required adjuvant chemotherapy when he developed large right lung metastases 6 months postoperatively.

CONCLUSIONS

PBRMS can be hardly distinguished from other malignant brain tumors during preoperative radiologic workup; only histology can raise the suspicion of primary or metastatic rhabdomyosarcoma, depending on the presence of other distant lesions. Our review of the literature demonstrates that prognosis is poor: 44% of patients die within 1 year from diagnosis. Overall, survival seems to correlate with radical resection, tolerance of stereotactic or if necessary full neuraxis radiotherapy, and adjuvant chemotherapy. Given the high relapse rate, close monitoring and restaging are imperative.

Primary Pineal Rhabdomyosarcoma: A Rare Case

Primary pineal rhabdomyosarcoma (RMS) is extremely rare, and only three cases have been reported so far. Here, we report a case of 12-year-old male who presented with complaints of diplopia and diminution of vision since 15 days. He also had left-sided facial paresis. Magnetic resonance imaging brain revealed a space-occupying lesion in the region of pineal gland. The patient underwent midline suboccipital craniectomy with excision of tumor. Microscopic examination revealed a highly cellular tumor with areas showing small round cells admixed with cells having abundant eosinophilic cytoplasm resembling rhabdomyoblasts and multinucleated giant cells. Differential diagnoses of pineal anlage tumor and primary RMS were considered. The tumor cells were positive for desmin while being negative for synaptophysin and glial fibrillary acidic protein. Myogenin was used to confirm the diagnosis of RMS, which showed focal nuclear positivity. INI1 was retained. All the markers for germ cell tumors were negative.

Misdiagnosis of primary pleomorphic rhabdomyosarcoma of the right thigh in a young adult: A case report

Pleomorphic rhabdomyosarcoma (PRMS) is a rare type of soft tissue tumor accounting for <2% of all adult sarcomas. The present study describes a case of a 28-year-old male patient with primary PRMS of the right thigh. The patient was initially diagnosed with a schwannoma and underwent conservative therapy at a local hospital. At the 6-month follow-up, the patient reported a marked increase in the size of the mass. Finally, the patient underwent fine-needle aspiration and total tumor resection. The tumor measured 11×9×5 cm3 in size and was located in the vastus intermedius muscle. According to histological and immunohistochemical findings, a diagnosis of PRMS was confirmed by an expert pathology consultant. Postoperative follow-up at 3 months revealed no evidence of recurrent disease or residual side effects from therapy. However, it is imperative that such cases are closely monitored following surgery, in order to evaluate the long-term efficacy of the procedure, since misdiagnosis may increase the risk of recurrence and metastasis. The present case is noteworthy due to the misdiagnosis of PRMS, the large size of the mass and the young age of the patient.