A case of subgaleal metastasis from glioblastoma multiforme

Rapid progression of subcutaneous glioblastoma: A case report and literature review

Extra-neural spread of glioblastoma (GBM) is extremely rare. We report a case of postoperative intracranial GBM spreading to the subcutaneous tissue via the channel of craniotomy defect in a 73-year-old woman. Radiological images and histopathology indicate that the tumor microenvironment of the subcutaneous tumor is clearly different from the intracranial tumor. We also model the invasion of GBM cells through the dura-skull defect in mouse. The retrospective analysis of GBM with scalp metastases suggests that craniectomy is a direct cause of subcutaneous metastasis in patients with GBM. Imaging examinations of other sites for systemic screening is also recommended to look for metastases outside the brain when GBM invades the scalp or metastasizes to it.

Extracranial metastasis of recurrent glioblastoma to the parotid gland: a case report and review of the literature

Background

Glioblastomas are the most common and highly malignant primary brain tumors in adults with a median survival of 15 months even with appropriate treatment. Extracranial metastases are extremely rare due to the poor prognosis not allowing sufficient time to spread. We report an extremely rare case of extracranial metastasis of supra-tentorial glioblastoma involving the skin, subcutaneous and muscular layers, periauricular region and parotid gland, and review the literature. A total of 13 glioblastoma parotid gland metastases cases have been hitherto described.

Main body of the abstract

A 42-year-old man underwent surgery for right temporal glioblastoma and received 60 Gy/30 fractions radiotherapy together with temozolomide at 75 mg/m2. Seven months later, the tumor relapsed and the patient underwent a second surgery while chemotherapy continued. Fifteen months later, he complained of swelling in the right neck region. Fine needle aspiration and tru-cut biopsy revealed a high-grade malignant tumor infiltration within the parotid gland. Despite salvage chemotherapy and adjuvant radiotherapy, in his follow-up after 6 months neck swelling increased. The patient declined any treatment modality and continues his life 39 months after the primary diagnosis of intracranial glioblastoma.

Short conclusion

Due to the recurrence rate of intracranial glioblastoma and its malignant nature; close imaging follow-up is highly crucial. The increase in reported cases of its extracranial metastases is generally due to the modern diagnostic tools and prolonged survival attributed to the improvement in treatment modalities where now radical surgery with adjuvant radiotherapy and chemotherapy is standard protocol. Patients with glioblastomas presenting with swelling in the cervical region should be investigated to rule out parotid gland metastasis.

Glioblastoma multiforme metastasizing to the skin, a case report and literature review

Glioblastoma Multiforme (GBM) is the most common primary central nervous system (CNS) malignancy in adults. It is very aggressive and is notorious for its fast and local invasion of nearby brain parenchyma. Consequently, the overall survival (OS) of patients with GBM is short despite resection, radiotherapy and chemotherapy regimens. The most common sites of metastasis of GBM are the lungs and pleura, cervical lymph nodes, and bone. Metastasis to the skin is a rare event and to our knowledge, there are less than 30 cases of GBM metastasizing to cutaneous or subcutaneous tissue described in the literature. None of these cases were diagnosed and/or treated in the Middle East region; and the majority of the metastases found were adjacent to the site of surgery undergone to remove the primary malignancy. We present the case of a 53-year-old male diagnosed with GBM and later showing signs of metastases at the anterio-auricular side of his face near-distant from the site of previous surgery done to remove the primary tumor.