case_images: PMC11418105_01
case_images: Case presentation with radiological evaluation with [18F]FDG-PET/CT (maximum intensity projections and fused axial images) and contrast-enhanced T1-weighted MRI of the brain. (A) Baseline, week minus 3 shows hypermetabolic supra-and infradiaphragmatic lesions on PET/CT. In the brain, a lesion can be noted parafalcine in the left (L) occipital lobe (4 mm; upper image) and no lesion is noted in the right (R) nucleus caudatus (lower image). (B) PET/CT in week 7 shows a significant decrease in metabolic activity as well as a decrease in size of the lesions (unconfirmed partial response). Brain MRI at week 5 shows a slight increase of the L occipital parafalcine lesion (7 mm, upper image), however there are no new lesions and considering a lead time bias of 3 weeks the treatment is continued. (C) On brain MRI in week 14, the parafalcine L occipital lesion has disappeared (upper image), a new lesion in the nucleus caudatus has emerged (lower image). (D) PET/CT in week 24 shows a metabolic remission extracranially. MRI shows an increased size of the lesion on the nucleus caudatus (lower image); SRS is performed for this lesion and 2 other progressive lesions (not shown). (E) PET-CT in week 66 shows a sustained complete metabolic remission, MRI in week 59 shows a shrinkage of the lesion in the nucleus caudatus (lower image), no other intracranial lesions are detectable on MRI. BID, twice a day; dab, dabrafenib; OD, once daily; SRS, stereotactic radiosurgery; trame, trametinib.
case_images: fmed-11-1436774-g001.jpg
case_images: PMC11418105_01_fmed-11-1436774-g001.jpg
case_images: fig1
case_images: She developed immune-related colitis after two cycles and progressed with seven new brain metastases (AJCC stage IV-1Md) (Figure 1A). RANO-BM criteria. Response assessment in week 7 with [18F]FDG-PET/CT showed complete metabolic response of extracranial lesions (Figure 1B). However, there was one new lesion (6 mm longest diameter) and an increased diameter of two preexisting metastases (Figure 1C). Following confirmed progression in these three lesions nearly 2 months later, they were treated with stereotactic radiosurgery (1 x 20 Gy) (Figure 1D). After 66 weeks of treatment, the patient remained in complete metabolic remission extracranially (Figure 1E). The week-59 brain MRI confirmed a continuing decrease in diameter of one of the irradiated lesions, and complete regression of the others (Figure 1E).
case_images: Case presentation of focal post-radiation necrosis of the brain (fRNB) with gadolinium contrast-enhanced T1-weighted and FLAIR MRI of the brain and [18F]FDG-PET/CT (FDG-uptake images). (A) First sign of fRNB (week 59 or 32 weeks after SRS) with contrast-enhancement in the paramedian frontal right region on the T1-weighted axial image (upper) and surrounding edema on the FLAIR axial image (lower). (B) In week 65 or 38 weeks after SRS there is an increase of contrast-enhancement in the paramedian frontal right region on the T1-weighted axial image (upper) and surrounding edema on the FLAIR axial image (lower). (C) PET-CT performed 1 week later (week 66 or 39 weeks after SRS) shows no increased uptake of [18F]FDG, supporting the diagnosis of fRNB. (D) In week 74 or 8 weeks after bevacizumab initiation there is a decrease of contrast-enhancement in the paramedian frontal right region on the T1-weighted axial image (upper) and surrounding edema on the FLAIR axial image (lower). SRS, stereotactic radiosurgery.
case_images: fmed-11-1436774-g002.jpg
case_images: PMC11418105_01_fmed-11-1436774-g002.jpg
case_images: fig2
case_images: While extra- and intracranial responses persisted, the week-59 brain MRI revealed signs of focal post-radiation necrosis of the brain (fRNB) approximately 8 months after SRS for the lesion in the paramedian frontal right region (Figure 2A). A brain MRI, repeated 6 weeks later, showed increase in contrast-enhancement and size of the region (Figure 2B), which was associated with headaches. A low-dose bevacizumab treatment regimen (previously established as effective treatment for fRNB) was initiated to treat the perilesional edema (Figure 2C). After two doses of bevacizumab (8 weeks) the headache subsided and MRI showed an important decrease in contrast-enhancement and edema (Figure 2D).