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

Multidisciplinary treatment is necessary in glioblastoma with extracerebral metastases

PURPOSE

While glioblastoma is the most common malignant brain tumor in adults, extracerebral manifestations are very rare in this highly aggressive disease with poor prognosis.

METHODS

We conducted a systematic literature review in the PubMed database and complemented the data by inclusion of a case treated in our clinic. In this context, we report on a 60-year-old woman with a right frontal glioblastoma, IDH wildtype, MGMT methylated.

RESULTS

Six months after initial diagnosis and primary treatment, there was extensive local intracranial progression with additional extension into the subcutaneous and frontotemporal cranial bones. Despite continuation of multimodal treatment, further extracerebral manifestations occurred 11 months after the initial diagnosis, both in the cranial bone as well as metastases in the right parotid gland, cervical lymph nodes, and lungs. While local radiotherapy enabled the cerebral lesions to be controlled, the patient's clinical condition deteriorated rapidly despite simultaneous systemic therapy. The treatment had to be discontinued, and the patient died 5 weeks after confirmation of the multilocal extracerebral manifestations and a total of 12 months after initial diagnosis.

CONCLUSION

Extracerebral manifestations of glioblastoma require close collaboration and joint decision-making with the patient, with an emphasis on palliative strategies.

Prediction of intracranial electric field strength and analysis of treatment protocols in tumor electric field therapy targeting gliomas of the brain

BACKGROUND AND OBJECTIVE

Tumor Electric Field Therapy (TEFT) is a new treatment for glioblastoma cells with significant effect and few side effects. However, it is difficult to directly measure the intracranial electric field generated by TEFT, and the inability to control the electric field intensity distribution in the tumor target area also limits the clinical therapeutic effect of TEFT. It is a safe and effective way to construct an efficient and accurate prediction model of intracranial electric field intensity of TEFT by numerical simulation.

METHODS

Different from the traditional methods, in this study, the brain tissue was segmented based on the MRI data of patients with retained spatial location information, and the spatial position of the brain tissue was given the corresponding electrical parameters after segmentation. Then, a single geometric model of the head profile with the transducer array is constructed, which is assembled with an electrical parameter matrix containing tissue position information. After applying boundary conditions on the transducer, the intracranial electric field intensity could be solved in the frequency domain. The effects of transducer array mode, load voltage and voltage frequency on the intracranial electric field strength were further analyzed. Finally, planning system software was developed for optimizing TEFT treatment regimens for patients.

RESULTS

Experimental validation and comparison with existing results demonstrate the proposed method has a more efficient and pervasive modeling approach with higher computational accuracy while preserving the details of MRI brain tissue structure completely. In the optimization analysis of treatment protocols, it was found that increasing the load voltage could effectively increase the electric field intensity in the target area, while the effect of voltage frequency on the electric field intensity was very limited.

CONCLUSIONS

The results showed that adjusting the transducer array mode was the key method for making targeted treatment plans. The proposed method is capable prediction of intracranial electric field strength with high accuracy and provide guidance for the design of the TEFT therapy process. This study provides a valuable reference for the application of TEFT in clinical practice.

Mesenchymal-Type Genetic Mutations Are Likely Prerequisite for Glioblastoma Multiforme to Metastasize Outside the Central Nervous System: An Original Case Series and Systematic Review of the Literature

BACKGROUND

Glioblastoma multiforme (GBM) is the most aggressive and prevalent type of malignant brain tumor, yet it metastasizes outside the central nervous system (CNS) in only 0.4% of cases. Little is known about what enables this subset of GBMs to take root outside the CNS, but genetic mutations likely play a role.

METHODS

We conducted a PRISMA-compliant systematic review of metastatic GBM wherein we reviewed 3579 search results and 1080 abstracts, analyzing data from 139 studies and 211 unique patients. In addition, we describe 4 cases of patients with pathologically confirmed GBM metastases outside the CNS treated at our institution.

RESULTS

We found that metastases were discovered near previous surgical sites in at least 36.9% of cases. Other sites of metastasis included bone (47.9%), lung (25.6%), lymph nodes (25.1%), scalp (19.2%), and liver (14.2%). On average, metastases were diagnosed 12.1 months after the most recent resection, and the mean survival from discovery was 5.7 months. In our patients, primary GBM lesions showed mutations in NF1, TERT, TP53, CDK4, and RB1/PTEN genes. Unique to the metastatic lesions were amplifications in genes such as p53 and PDGFRA/KIT, as well as increased vimentin and Ki-67 expression.

CONCLUSIONS

There is strong evidence that GBMs acquire novel mutations to survive outside the CNS. In some cases, tumor cells likely mutate after seeding scalp tissue during surgery, and in others, they mutate and spread without surgery. Future studies and genetic profiling of primary and metastatic lesions may help uncover the mechanisms of spread.

Metastatic glioblastoma to the lungs: a case report and literature review

Glioblastoma is the most common malignant primary brain tumor. Despite its infiltrative nature, extra-cranial glioblastoma metastases are rare. We present a case of a 63-year-old woman with metastatic glioblastoma in the lungs. Sarcomatous histology, a reported risk factor for disseminated disease, was found. Genomic alterations of TP53 mutation, TERT mutation, PTEN mutation, and +7/-10 were also uncovered. Early evidence suggests these molecular aberrations are common in metastatic glioblastoma. Treatment with third-line lenvatinib resulted in a mixed response. This case contributes to the growing body of evidence for the role of genomic alterations in predictive risk in metastatic glioblastoma. There remains an unmet need for treatment of metastatic glioblastoma.

Extracranial metastasis of brain glioblastoma outside CNS: Pathogenesis revisited

BACKGROUND

The most prevalent malignant tumor of the CNS in adults is glioblastoma. Despite undergoing surgery and chemoradiotherapy, the prognosis remains unfavorable, with a median survival period ranging between 15 and 20 months. The incidence of glioblastoma metastasis outside CNS is uncommon with only 0.4%-2% reported rate, compared to other tumors that exhibit a 10% incidence rate of metastasis to the brain. On average, it takes about 11 months from the time of initial diagnosis for the tumor to spread beyond CNS. Consequently, the prognosis for metastatic glioblastoma is grim, with a 6-month survival rate following diagnosis.

FINDINGS

The rarity of extracranial metastasis is attributed to the blood-brain barrier and lack of a lymphatic drainage system, although rare cases of hematogenous spread and direct implantation have been reported. The possible mechanisms remain unclear and require further investigation. Risk factors have been widely described, including previous craniotomy or biopsies, ventricular shunting, young age, radiation therapy, prolonged survival time, and tumor recurrence. Due to the lack of understanding about extracranial metastasis of glioblastoma pathogenesis, no effective treatment exists to date. Aggressive chemotherapies are not recommended for metastatic glioblastoma as their side effects may worsen the patient prognosis.

CONCLUSION

The optimal treatment for extracranial metastasis of glioblastoma requires further investigation with a wide inclusion of patients. This review discusses the possible causes, factors, and underlying mechanisms of glioblastoma metastasis to different organs.

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.