Perineural spread of tumor

Imaging of
cranial nerves: a pictorial overview. Perineural spread of tumor. Patient with squamous carcinoma of the retromolar trigone. CT sagittal images at 0 (a), 6 (b), and 12 (c) months follow-up. Note the progressive infiltration (arrows) of the pterygopalatine fossa (asterisks) with obliteration of the normal fatty tissue. In (c), it is evident the invasion of Meckel’s cave (empty arrow)
insightsimaging.springeropen.com • CC-by-4.0
Perineural
spread of tumor • Perineural spread of squamous cell carcinoma: infra-orbital nerve - Ganzer Fall bei Radiopaedia
O'Donnell C, Perineural spread of squamous cell carcinoma: infra-orbital nerve. Case study, Radiopaedia.org (Accessed on 03 Jan 2023) https://doi.org/10.53347/rID-37559 • CC by-nc-sa 3.0 (modified)
Perineural
spread of tumor • Perineural spread of tumor along infraorbital nerve - Ganzer Fall bei Radiopaedia
O'Donnell C, Perineural spread of tumor along infraorbital nerve. Case study, Radiopaedia.org (Accessed on 03 Jan 2023) https://doi.org/10.53347/rID-59389 • CC by-nc-sa 3.0 (modified)
Perineural
spread of tumor • Meckel cave/cavernous sinus meningioma with perineural spread - Ganzer Fall bei Radiopaedia
Knipe H, Meckel cave/cavernous sinus meningioma with perineural spread. Case study, Radiopaedia.org (Accessed on 03 Jan 2023) https://doi.org/10.53347/rID-57945 • CC by-nc-sa 3.0 (modified)
Perineural
spread of tumor • Perineural invasion of SCC along great auricular nerve - Ganzer Fall bei Radiopaedia
Beames C, Perineural invasion of SCC along great auricular nerve. Case study, Radiopaedia.org (Accessed on 03 Jan 2023) https://doi.org/10.53347/rID-73669 • CC by-nc-sa 3.0 (modified)
Imaging of
cranial nerves: a pictorial overview. Perineural spread of tumor. Patient with squamous carcinoma of the retromolar trigone. MRI T1-weighted post-gadolinium image shows diffuse neoplastic enhancement in the left pterygopalatine fossa, cavernous sinus and Meckel’s cave (dotted circle)
insightsimaging.springeropen.com • CC-by-4.0
Imaging of
cranial nerves: a pictorial overview. Perineural spread of tumor. MRI T1-weighted post-gadolinium axial (a) and coronal (b) images. Note the enlargement and the enhancement of the mandibular branch of trigeminal nerve (V2) (dotted circles)
insightsimaging.springeropen.com • CC-by-4.0
Radiopaedia • CC-by-nc-sa 3.0 • de

Perineural spread of tumor is a form of local invasion in which primary tumors cells spread along the tissues of the nerve sheath.  It is a well-recognized phenomenon in head and neck cancers.

Terminology

An important distinction has to be made between perineural invasion (PNI) and perineural spread (PNS). The former is a histological finding of tumor cell infiltration or associated with small nerves that cannot be radiologically imaged, while the latter is macroscopic tumor involvement along a nerve extending away from the primary tumor; this can be radiologically apparent. A third term, neurotropism, simply means that a tumor has an affinity for growth along nerves.

Pathology

Perineural tumor spread is more frequently associated with :

Radiographic features

MRI

Signs on MRI suggesting perineural tumor spread are:

  • nerve thickening
  • widening of the neural foramen
  • loss of the fat surrounding the nerve
  • abnormal perineural contrast enhancement

Differential diagnosis

Siehe auch: