Akihiko Sugimoto

<jats:p>A 69-year-old man presented with hoarseness and cervical swelling. CT revealed a neck tumor and lymph node metastasis. Somatostatin receptor scintigraphy (SRS) showed mild lesion uptake. Intravenous tumor thrombus into the right internal jugular and vertebral vein was suggested by FDG-PET/CT and confirmed by Contrast-enhanced CT. Biopsy revealed squamous cell carcinoma (SCC). The tumor location and thrombosis suggested ectopic thymic origin. Immunostaining for markers CD117 and POU2F3 was positive, confirming ectopic thymic SCC. Chemotherapy was initiated, with tumor reduction after 6 months. This case highlights the usefulness of FDG-PET/CT suggestion of tumor thrombus and SRS accumulation in the diagnosis of ectopic thymic carcinoma.</jats:p>

Erdheim-Chester disease (ECD) is a rare type of non-Langerhans cell histiocytosis, characterized by the infiltration of disease-specific foamy histiocytes, polymorphic granulomas, and fibrosis. Although cardiovascular involvement is observed radiologically in approximately half of ECD patients, only a few reports have described its pathological features. We herein report the autopsy of an ECD patient with pulmonary, cardiovascular, and retroperitoneal involvement that may have caused his death. Autopsy revealed the pathological association of coronary and renal arterial stenosis with the BRAF^V600E gene mutation. BRAF mutations should be considered in patients with ECD, especially in those with arterial lesions.

<h4>Background</h4>Chondrosarcoma is typically a slow-growing tumor, and intratumoral hemorrhage is rare. Acute brainstem hemorrhage due to chondrosarcoma has rarely been reported.<h4>Observations</h4>A 77-year-old man presented with the sudden onset of headache and vomiting followed by a declining level of consciousness, progressive right hemiparesis, and left ophthalmoplegia. Magnetic resonance imaging showed pontine hemorrhage and a mass in the retroclival space compressing the brainstem. Emergency endoscopic endonasal surgery was performed. Intraoperative observation revealed that a hematoma was located in the pons and subdural space around the tumor mass, suggesting that the hematoma had likely been caused by the rupture of small vessels around the pons, not by intratumoral hemorrhage. The pathological diagnosis was chondrosarcoma. The patient recovered well and underwent radiotherapy.<h4>Lessons</h4>This report describes a case of sudden neurological deterioration due to hemorrhage in a patient with chondrosarcoma of the skull base. An emergency endoscopic endonasal approach for mass reduction and hematoma removal was effective in the acute setting. This approach revealed the suspected etiology of peritumoral hemorrhage, not intratumoral hemorrhage. https://thejns.org/doi/10.3171/CASE2460.

Radiation-induced angiosarcoma is a highly aggressive malignancy. We encountered a case of angiosarcoma arising in the bilateral breast seven years after partial mastectomy and the last radiation therapy. As recommended, wide resection with skin grafting was performed to ensure negative surgical margins. After surgery, taxane-based chemotherapy was administered. However, adjuvant chemotherapy was discontinued because of drug-induced institutional pneumonia. Eighteen months postoperatively, angiosarcoma recurred in subcutaneous, lymph nodes, lungs, and bones. The disease progressed too rapidly, and the patient died two months after recurrence.

<h4>Abstract</h4>A 70-year-old woman under amlodipine treatment for hypertension presented with a hemorrhagic mass in the mandibular gingiva. Imaging studies revealed high signal intensity in T2-weighted MRI and moderate 18F-FDG accumulation at the lesion's periphery. Although no malignancy was detected, the lesion continuously grew, prompting excision. Histopathological examination confirmed gingival hyperplasia attributed to amlodipine use. Drug-induced gingival hyperplasia typically presents as diffuse swelling; however, this lesion manifested as a polyp, posing diagnostic challenges. Reports on imaging findings for drug-induced gingival hyperplasia are limited. Understanding imaging patterns alongside clinical history aids in accurate diagnosis.