Brain abscess of odontogenic origin in patients with malignant tumors: A report of two cases.

BACKGROUND: Oral infection and dental manipulations can lead to the development of brain abscesses, a rare but potentially life-threatening condition. Herein, we report patients undergoing cancer treatment who developed brain abscesses of odontogenic origin at our hospital. CASE DESCRIPTION: Two patients developed brain abscesses during cancer treatment. Both underwent neurosurgical aspiration, and the causative microorganism was identified as Streptococcus intermedius of the Streptococcus anginosus group, which is a part of the normal bacterial flora in the oral cavity. There was clinical and radiographic evidence of dental infection in one of the patients diagnosed with a brain abscess of odontogenic origin. No infectious foci were found in the other patient during hospitalization for the abscess. However, the patient had undergone extraction of an infected tooth approximately 3 months before admission for the abscess, suggesting origination from an oral infection or dental manipulation. The patients' cancers rapidly worsened because cancer treatment in both patients was interrupted for several months to treat the brain abscess. CONCLUSION: Oral infections can cause severe infections, such as brain abscesses, particularly during the treatment of malignant tumors. Improving the oral environment or treating oral infections before initiating treatment for malignant tumors is highly recommended. In addition, the possibility of odontogenic origin should always be considered as a potential etiology of brain abscesses.

Transbrachial carotid artery stenting can prevent renal cholesterol embolism.

A 78-year-old man was admitted for the treatment of internal carotid artery stenosis. The left internal carotid artery was occluded and stenosis of the right internal carotid artery was progressive. The patient had a history of renal cholesterol embolism associated with percutaneous peripheral intervention. Stenting of the right internal carotid artery was successfully performed via the right brachial artery, and cholesterol embolism was not noted after the procedure. This case suggests that carotid artery stenting (CAS) performed via a brachial approach is less likely to elicit cholesterol embolism than CAS performed via a femoral approach.

[A case of malignant paraganglioma presenting with skull metastases].

A non-functioning paraganglioma is usually benign, however, it may cause distant metastases. There is no histological appearance for the diagnosis of malignancy or absolute criteria for predicting malignant potential. Bony metastases from paraganglioma are known to occur, but, skull metastases are very rare. We report a case of intracranial metastases from a renal paraganglioma. A 61-year-old male presented with temporal headache and exophthalmos on the left side. Seven years prior, he underwent surgery to remove a mass in the right renal hilum, which was diagnosed as renal cell carcinoma at that time. Computed tomography and magnetic resonance imaging showed a ring-like enhanced mass in the left middle fossa, which destroyed the sphenoid bone and the lateral wall of the orbit. Another osteolytic lesion was revealed in the occipital bone. The fragile tumor was totally resected. Histopathological study revealed the Zellballen pattern with extensive coagulation necrosis. No apparent nuclear atypia or mitosis were present. Immunohistochemistry showed reactivity for synaptophysin and chromogranin A in the tumor cells. Review of the surgical specimen of the previously resected renal tumor revealed the same pathological and immunohistochemical findings as those of chief cells in the middle fossa tumor. Thus, this tumor was diagnosed as a malignant paraganglioma metastasized from renal paraganglioma. After six cycle chemotherapy with cyclophosphamide and vincristine, his condition was stable for two years, however, he died four years after the diagnosis of malignancy.