A Novel Homozygous Founder Variant of RTN4IP1 in Two Consanguineous Saudi Families.

The genetic architecture of mitochondrial disease continues to expand and currently exceeds more than 350 disease-causing genes. Bi-allelic variants in RTN4IP1, also known as Optic Atrophy-10 (OPA10), lead to early-onset recessive optic neuropathy, atrophy, and encephalopathy in the afflicted patients. The gene is known to encode a mitochondrial ubiquinol oxidoreductase that interacts with reticulon 4 and is thought to be a mitochondrial antioxidant NADPH oxidoreductase. Here, we describe two unrelated consanguineous families from the northern region of Saudi Arabia harboring a missense variant (RTN4IP1:NM_032730.5; c.475G

Parotid Gland Solitary Fibrous Tumor Presenting as a Long Duration Mass: A Case Report.

The solitary fibrous tumor (SFT) is a tumor of uncertain histogenesis, affecting deep soft tissues, particularly the pleura (pulmonary) and extrapulmonary sites including thighs, retroperitoneum, other serosal surfaces, and cranial and spinal meninges. SFT and hemangiopericytoma are now considered the same entity, with general agreement on referring to this group of tumors as "SFT." SFTs are generally benign tumors with small subsets of malignant ones. Moreover, they are well-circumscribed with a good prognosis after surgical resection. SFTs are uncommon in the head and neck and are quite rare in the parotid gland region. Here, we present a case of a 48-year-old female with SFT of the parotid gland region; the diagnosis was confirmed by positive immunohistochemical staining for Bcl-2, CD34, and STAT6. STAT6 immunohistochemistry is sensitive and specific for SFTs.

Right Temporal Brain Metastases Arising Three Years after Curative Resection of Gastric Cancer: A Case Report.

BACKGROUND: Gastric cancer can metastasize to multiple organs but the metastases to brain is very rare. We report a case of recurrent gastric cancer. The only site of recurrence is brain metastases that occurred three years after curative resection. CASE PRESENTATION: A 58-year-old male patient who was diagnosed to have gastric cancer. He received neoadjuvant chemotherapy then complete resection. The patient came to the outpatient clinic for regular follow up. After three years from resection the patient complained of headache and seizures. CT scan brain showed right temporal bone localized tumor. Complete resection was done which revealed it is a localized metastases from gastric cancer. CONCLUSION: Localized brain metastases from gastric cancer is a rare event. Urgent CT scan must be done if the patient had any neurological complaint. Early diagnosis is the key for the patient management. Rapid treatment can improve the patient general condition and neurological manifestations.

Follicular dendritic cell sarcoma of parapharyngeal space: a case report and review of the literature.

Follicular dendritic cell sarcoma (FDCS) of the parapharyngeal space is a rare malignant tumor. Only eleven cases of FDCS of the parapharyngeal space have been reported in English literature. Most of the reported cases developed tumor recurrence within 1 year or had metastasis. Because of the rarity of FDCS in the parapharyngeal space and peculiar histology, it can be misdiagnosed as undifferentiated carcinoma or meningioma. Therefore, pathologists should be aware of the existence of FDCS in this location. This paper aims to report a unique case of FDCS of the parapharyngeal space without recurrence in 26 months follow up with a review of the literature.

Lateral pharyngeal wall myeloid sarcoma as a relapse of acute biphenotypic leukemia: a case report and review of the literature.

INTRODUCTION: Myeloid sarcoma is a rare extramedullary malignant tumor composed of immature myeloid cells. The tumor can affect any part of the body. Involvement of the oral cavity and nasopharynx has been reported in 50 cases. We report a case describing myeloid sarcoma affecting the lateral pharyngeal wall. CASE PRESENTATION: A 31-year-old Arabian man who had acute biphenotypic leukemia treated with chemoradiation and allogeneic stem cell transplant was referred to our department with sore throat and a mass lesion in his lateral pharyngeal wall after failed antibiotic therapy. Biopsy of his lesion revealed myeloid sarcoma. He was referred to the Department of Hematology-Oncology for further evaluation that showed no other lesions.The patient was diagnosed with isolated extramedullary myeloid sarcoma of his lateral pharyngeal wall as a relapse of acute biphenotypic leukemia and managed with chemoradiation. CONCLUSIONS: Myeloid sarcoma of the pharynx is a rarely encountered malignancy in the practice of otolaryngology-head and neck surgery. It can develop de novo, but may also represent relapse of leukemia. Thus, it should be considered in the differential diagnosis of any pharyngeal lesions in patients with leukemia.

Posterior fossa tumor in a 2 year-old girl.

We report a case of a 2 year-old girl who presented with three weeks' history of deterioration of walking, then became unable to walk and later she developed projectile vomiting. Neurological examination revealed bilateral papilledema, nystagmus, and truncal ataxia with intention tremor. Radiological studies showed an enhancing mass in the posterior fossa extending from the cerebellum to the roof of the fourth ventricle. The tumor was diagnosed as an embryonal tumor with abundant neuropil and true rosettes (ETANTR). The tumor cells in the neuroblastic component were diffusely positive for synaptophysin and CD56, with scattered positive cells for glial fibrillary acidic protein. The true rosettes were only positive for vimentin. Ki67 showed high index (over 90%) in the true rosettes, while the neuroblastic areas were up to 15%. Our patient developed recurrent disease 6 months after resection and chemotherapy. ETANTR is a very rare aggressive embryonal CNS tumor that combines features of neuroblastoma and ependymoblastoma. We review the thirteen cases reported in the literatures. This case represents the second report of an ETANTR arising in the cerebellum.