A case of mediastinal mesenchymal tumor with pericytic neoplasm feature that responded to radiation therapy.

Here, we report a case of mediastinal mesenchymal tumor with a pericytic neoplasm feature that responded to radiation therapy. A 43-year-old man visited our hospital with a complaint of esophageal obstruction and chest pain. Chest computed tomography revealed a middle mediastinal tumor and a mesenchymal tumor was diagnosed with a pericytic neoplasm feature by video-assisted thoracoscopic biopsy. The definitive treatment for soft tissue tumor is surgical resection; however, the mediastinal tumor was unresectable because of esophageal and tracheal invasion. Radiation therapy was administered and there was a partial tumor response and 2 years disease-free status. With a review of the literature, we discuss the clinical and pathological characteristics of this rare tumor and its treatment.

Rare sphenoid ridge intracranial mature teratoma in an adult female.

Intracranially located teratomas usually involve midline brain structures. However, they rarely occur in adults. A 26-year-old woman presented with a growing intracranial mass lesion in the left sphenoid ridge without neurological deficits. Magnetic resonance imaging revealed homogenous hyperintensities without contrast enhancement. The patient underwent gross total excision of the soft, yellowish sphenoid ridge tumor with no cystic component. The surgery was uneventful, with no intraoperative complications. Histological analysis revealed a mature teratoma. She attended regular outpatient neuroradiology follow-up appointments. The present case is an unusual example of a mature teratoma with regard to location, neuroimaging appearance, macroscopic intraoperative findings, histological tumor subtype, and patient age and sex.

Ultrastructure of CIC-DUX4 sarcoma: the first pathological report.

CIC-DUX4 sarcoma (CDS) is a recently identified subtype of small round cell sarcoma. Morphologically, CDS partially resembles Ewing sarcoma (ES) and has been classified as "ES-like sarcoma"; however, detailed clinicopathologic and molecular genetic analyses have indicated that CDS is a new independent disease. Many studies have provided light microscopic, immunohistochemical, and genetic information about CDS. However, ultrastructural findings associated with this sarcoma are lacking. The aim of this study was to investigate the ultrastructure of CDS tumors and to compare their features with those of ES. We examined two cytogenetically confirmed CDS cases. We found that, compared to typical ES, CDS presented heterogeneity: in cell density, from tightly packed to loosely unconnected areas; in cell shape, from polygonal to pleomorphic with small processes; and in nuclear shape including round, oval, polygonal, elongated, invaginated, or wrinkled formations. However, abundant glycogen in the cytoplasm and rare cell adhesion apparatus between cells are major similarities between CDS and typical ES. Neuroendocrine granules, which are seen in rare ES cases, could not be identified in these two CDS cases. Although cytogenetic differences can validate a definite diagnosis, ultrastructural features could also provide important information about the differences between CDS and ES.

Late and Rapid Relapse in Mediastinum from Testicular Germ Cell Tumor Stage I Over 13 Years after Surgery.

Patients with stage I testicular germ cell tumors have a long life expectancy, but the tumors have a potential to relapse after treatment. Although relapse is observed within a few years in most cases, late relapse over 10 years after initial treatment has also been reported in patients with stage I testicular germ cell tumors. We encountered a case of testicular seminoma that developed mediastinal lymph node metastasis 13 years after radical surgery for the primary tumor. The relapsed disease progressed rapidly and the patient died within 1 month due to respiratory failure without any chance for therapy. On postmortem examination, the thoracic lesions were pathologically confirmed to be metastases from the testicular seminoma with yolk sac tumor. Here, we report the clinical course and a review of the relevant literature. Based on our experience, we emphasize long-term follow-up and/or careful examination in patients with stage I testicular germ cell tumors.

Atypical teratoid/rhabdoid tumor of the sellar region in adult women: Is it a sex-related disease?

Atypical teratoid/rhabdoid tumor (AT/RT) is a highly malignant embryonal tumor in children and a rare entity. Although adult AT/RT is extremely rare, some cases of adult-onset AT/RT in the sellar region have been described. Here, we report an adult patient with AT/RT of the sellar region in whom it was difficult to make a definitive diagnosis and the clinical course was aggressive. This is the first report of autopsy findings that could confirm the clinical characteristics of this rare unresolved pathology, and will contribute to the improvement of prognosis. In addition, a literature review was performed to clarify this exceptionally rare condition. Interestingly, all reported adult patients with sellar AT/RT, along with the present case, were female. This raises the possibility of its being a sex-related disease. However, further studies are required to come to a definitive conclusion.

Successful Resection of G719X-Positive Pleomorphic Carcinoma after Afatinib Treatment.

We report a case of pleomorphic carcinoma with exon 18 mutation (G719X) of the epidermal growth factor receptor (EGFR), which showed good response to afatinib and resulted in successful resection. To our knowledge, this is the first report on the use of afatinib for pleomorphic carcinoma followed by the surgical resection. The patient was a 59-year-old woman, who visited our hospital because chest computed tomography showed a 28 × 28-mm nodule in the left upper lobe. Bronchoscopy was performed and the histological findings of transbronchial biopsy revealed adenosquamous carcinoma positive for G719X mutation in exon 18 of the EGFR. Since fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography revealed a positive accumulation in the bilateral hilar and mediastinal lymph nodes, the disease was diagnosed as cT1bN3M0, stage IIIB. After 3 months of afatinib therapy, FDG accumulation in primary tumor was almost gone. However, FDG accumulation in lymph nodes remained unchanged. Video-assisted thoracic surgery was planned for further diagnostic information and left upper lobectomy with mediastinal lymph node dissection was performed. The resected tumor included adenocarcinoma, squamous cell carcinoma, and spindle cell components, without lymph node metastasis. Thus, the disease was diagnosed as pleomorphic carcinoma (pT2aN0M0, stage IB). All components in the resected specimen had the same G719X mutation in exon 18 of the EGFR. The patient has shown no signs of recurrence at 1 year after the operation. The present case indicates the possibility of minor EGFR mutations in pleomorphic carcinoma and successful outcome by the use of afatinib and surgical resection.