Lung carcinoma metastasic to a brain meningioma

Case contributed by RMH Neuropathology


Patient diagnosed with a left lung carcinoma.

Patient Data

Age: 51
Gender: Female

CT Chest (selected images)

Left bronchial pulmonary solid mass in keeping with lung cancer. 


CT Brain (selected images)

A solid and vivid enhancing extra-axial mass is identified in the right middle cranial fossa. There are some minor calcifications within this mass. Findings are in keeping with a right sphenoid meningioma. 

Nuclear medicine

18F-FDG PET CT (selected images)

18F-FDG PET CT showing high glucose capitation within the lung mass and metastatic mediastinal nodes. On the brain images there is a lack of capitation in the right middle cranial fossa where was spotted the extra-axial mass. 

The right middle cranial fossa is again demonstrated with features that suggest a meningioma. 


CT Brain (6 months later)

There is a marked increase in the right middle cranial fossa mass which now has mass effect over the adjacent parenchyma. The lesion keeps it vivid enhancement pattern. 

Two new lesions with ring enhancement pattern and mild surrounding vasogenic edema are identified on the right cerebellar hemisphere and on the left frontal lobe. These lesions are in keeping with metastases. 


MRI Brain (Stereotaxis - selected images)


MICROSCOPIC DESCRIPTION: 1. The sections show features of meningioma. No metastatic tumor is seen. 2. The sections show features of metastatic moderately differentiated adenocarcinoma. The tumor forms many glandular structures. The tumor cells have enlarged nuclei, prominent nucleoli and moderate amounts of pale cytoplasm. In some areas, the tumor forms trabeculae and cords but the tumor cells are rather crushed. They seemingly have higher N/C ratio. No evidence of lymphovascular invasion is noted. The carcinoma is seen to invade into a meningioma. The meningioma forms whorls. The tumor cells have ovoid nuclei with no nuclear pleomorphism. Mitoses are inconspicuous. No brain invasion is seen. No evidence of atypical or malignant change is identified. The tumor cells from the carcinoma are CK7 and TTF-1 positive, in keeping with lung primary. All the glands and crushed areas are synaptophysin positive, indicating neuroendocrine differentiation. However, the morphology is not typical for large cell neuroendocrine carcinoma or small cell carcinoma. The tumor cells from the meningioma are diffusely progesterone receptor positive. The Ki-67 index is about 2%.

DIAGNOSIS: 1,2. Brain tissue: Metastatic moderately differentiated adenocarcinoma with neuroendocrine differentiation, in keeping with lung primary, invading into a grade I meningioma. 

Case Discussion

This case illustrates a meningioma incidentally found during oncologic staging for a lung carcinoma

In a period of months this meningioma demonstrated large increase in its volume together with the development of two new cerebral ring enhancing lesions that had imaging characteristics favoring metastases. The prominent increase of the right middle cranial fossa lesion raised the suspicion for an atypical meningioma or a metastatic involvement to this known vascularized tumor. 

The patient was submitted to the resection of this lesion which showed to be a metastatic carcinoma within the right middle cranial fossa meningioma.  

This condition is well known and referred as a tumor-to-tumor metastasis.

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Case information

rID: 39727
Published: 17th Sep 2015
Last edited: 14th Aug 2019
Inclusion in quiz mode: Included

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