Secretory meningioma with KLF4 K409Q mutation in collision with glioma.

AIMS: The simultaneous occurrence of two primary intracranial tumors is a rare event, especially if unrelated to radiotherapy or genetic disorders. We present two patients, both with two primary intracranial tumors simultaneously present at adjacent sites, in order to explore a possible mechanism of synchronous tumor formation. METHODS: We performed a molecular analysis of the K409Q mutation of the KLF4 gene, in addition to conventional immunohistochemistry. RESULTS: Preoperative gadolinium-enhanced magnetic resonance imaging revealed a necrotic mass with an irregular ring-like enhancement adjacent to a frontal meningioma in patient 1, and an infiltrative non-enhancing glial tumor with no evidence of another tumor in patient 2. Postoperative histological examination revealed the presence of two distinct tumors in both cases: secretory meningioma and glioblastoma in patient 1 and secretory meningioma and anaplastic astrocytoma in patient 2. Secretory meningiomas both showed the KLF4 K409Q mutation, while none of the glial tumors had it. CONCLUSIONS: To our knowledge, these are the first two cases reported of the simultaneous occurrence of secretory meningiomas with mutation of KLF4 in collision with a glioblastoma and an anaplastic astrocytoma, respectively. These collision tumors presumably have different molecular origins.

MR evaluation of fetal demise.

BACKGROUND: Fetal demise is an uncommon event encountered at MR imaging. When it occurs, recognition by the interpreting radiologist is important to initiate appropriate patient management. OBJECTIVE: To identify MR findings of fetal demise. MATERIALS AND METHODS: Following IRB approval, a retrospective search of the radiology fetal MR database was conducted searching the words "fetal demise" and "fetal death." Fetuses with obvious maceration or no sonographic confirmation of death were excluded. Eleven cases formed the study group. These were matched randomly to live fetuses of similar gestational age. Images were reviewed independently by three pediatric radiologists. RESULTS: The deceased fetus demonstrates decreased MR soft-tissue contrast and definition of tissue planes, including loss of gray-white matter differentiation in the brain. The signal within the cardiac chambers, when visible, is bright on HASTE sequences from the stagnant blood; the heart is small. Pleural effusions and decreased lung volumes may be seen. Interestingly, the fetal orbits lose their anatomical round shape and become smaller and more elliptical; a dark, irregular rim resembling a mask may be seen. CONCLUSION: Although fetal demise is uncommonly encountered at MR imaging, radiologists should be aware of such imaging findings so prompt management can be instituted.