A 71-year-old man presented with left-sided neck stiffness, severe headache, nausea and vomiting. Nine years earlier, brain MRI performed for vertigo had demonstrated an enhancing extra-axial lesion in the left cerebellopontine angle (CPA), initially presumed to be a meningioma (Figure 1A). In this presentation, head CT showed a well-defined hyperdense CPA mass (Figure 1B–G), and MRI confirmed the lesion (Figure 1H–M). Urgent resection was undertaken and pathology revealed hemangioblastoma. Two years later, the patient developed recurrent headaches and underwent a second subtotal resection, again consistent with hemangioblastoma. Six months after this, he reported left facial numbness and retro-orbital pain. MRI revealed an enlarging lesion in the left Meckel’s cave, and biopsy via a trans-sphenoidal trans-pterygoid approach confirmed recurrent hemangioblastoma (Figure 2).

Figure 1.

Top row, brain MRI T1-weighted post gadolinium image (A) – initial presentation with an incidental tiny enhancing lesion adjacent to the left foramen of Luschka choroid plexus (small red arrow). 9-year follow up CT head without contrast (B) and brain MRI with FLAIR (C), T2 (D), SWI (E), T1 pre gadolinium (F) and T1 fat saturated post gadolinium (G) sequences, showing interval focal subarachnoid hemorrhage (blue asterisk) and hemorrhagic extra-axial lesion in the left cerebellomedullary cistern with peripheral enhancement (red arrows), significantly increased from prior. Bottom row, 1 year 6 months consecutive follow-up. Multisequence axial brain MRI with T1 fat saturated post gadolinium (H, I and J), T2 (K), diffusion (L) and FLAIR (M) images. There has been interval development of an extra-axial lesion without diffusion restriction in the left Meckel’s cave (orange arrows).

Figure 2.

Proliferation of stromal cells with moderate amount of pale-staining to clear cytoplasm and mildly atypical, hyperchromatic nuclei (A; H&E; 100X magnification). These cells were intertwined by a rich network of thin-walled capillaries (B; H&E; 400X magnification). Immunohistochemistry revealed that the neoplastic cells were strongly positive for α-inhibin (C; 200X magnification) and negative for PAX8 (D; 200X magnification).

Hemangioblastomas represent approximately 2% of intracranial tumors and are typically intra-axial, most often in the cerebellum. Extra-axial locations such as the CPA or Meckel’s cave are exceedingly rare, with only isolated cases documented. ^{Reference Lopes Dos Santos, Trevas and Rosado1} These tumors can mimic meningiomas or vestibular schwannomas, making preoperative diagnosis challenging. CTA and MRI are particularly valuable, as they demonstrate the vascular nature of the lesion and can reveal serpentine flow voids, a distinguishing feature from more common extra-axial tumors. ^{Reference Wizigmann-Voos and Plate2,Reference Shih and Smirniotopoulos3} Although classically cystic with an enhancing mural nodule, hemangioblastomas may also present as purely solid lesions. ^{Reference Lee, Sanches, Mark, Dillon, Norman and Newton4}

Despite their benign histology, hemangioblastomas are associated with recurrence, especially when adherence to cranial nerves or the brainstem precludes complete excision. Reported recurrence rates range between 6% and 20%. ^{Reference Gupta, Pal and Sardhara5} Risk factors include multiple mural nodules, poorly defined cystic capsules and proximity to eloquent structures. Histologically, they are composed of a dense capillary network with stromal cells showing large nuclei and vacuolated cytoplasm, explaining their highly vascular nature and surgical challenges. ^{Reference Wizigmann-Voos and Plate2}

This case highlights an unusual site of recurrence in Meckel’s cave, underscoring the importance of considering vascular tumors in the differential diagnosis of CPA lesions. Recognition of their characteristic imaging features is essential for accurate diagnosis and surgical planning. Given their potential for recurrence, even after resection, long-term follow-up is warranted. Radiation therapy may provide an additional option for patients in whom complete resection is not feasible. Awareness of such atypical presentations can aid clinicians in avoiding misdiagnosis and tailoring management strategies for these rare but significant tumors.