Patterns of Perineural Tumor Spread in Head and Neck Cancer

Incidence rate of Sinonasal Malignancy in Western Province of Kingdom of Saudi Arabia

“…This finding is also one of the apparent in our study, and recurrence rate was recorded as 58% with very low prognosis in case of extension into the surrounding structures 12,17 .…”

Perineural spread of malignant melanoma from the mandible to the brachial plexus: case report

“…The spread of the tumor usually follows a retrograde (toward the central nervous system) direction, meaning that the skull base, the cranial foramina, and even intracranial structures can be affected. 8,13,17,18 As in this case, anterograde spread can also occur. Approximately 40% of patients with perineural spread remain asymptomatic, 18 making the diagnosis challenging.…”

“…This mechanism of tumor spread for metastatic melanoma is well known to occur along the cranial nerves and cervical plexus. 4,9,14,[16][17][18] We describe a rare example of documented perineural spread of melanoma, arising in the mandible and extending along a cranial nerve, the cervical plexus, and into the brachial plexus. We correlate the clinicoradiological features and propose an anatomopathological explanation to support the mechanism of perineural spread in this case.…”

MRI Sequences in Head & Neck Radiology – State of the Art

“…cysts, sinus tracts, fistulae or cartilaginous remnants based on location and clinical symptoms [4] sinonasal inverted papilloma convoluted cerebriform pattern on T2w and T1wC+ [6] paraganglioma "salt and pepper" appearance (30 -40 %) [7] cancer intermediate to high signal in T2w, high signal in T1wC+, mass, infiltration, inhomogeneity, necrosis perineural invasion T2w and T1w thickening and T1wC+ contrast enhancement along the cranial nerve [8] dural invasion nodular dural enhancement on T1wC+ and width of enhancement of more than 5 mm [9] mandibular bone invasion replacement of peripheral hypointense signal (cortical bone) through either tumor signal intensity on both T1w and T2w, or central hyperintense signal (medullary bone) is replaced by intermediate tumor signal [11] neoplastic invasion of laryngeal cartilages low T1w signal, similar to that of tumor T2w signal and similar to tumor T1wC+ signal [12] residual cancer after chemoradiation therapy intermediate T2 signal intensity similar to that of the untreated tumor with areas formed a focal expansible mass > = 1 cm [14] dissection high T1w signal in the vessel wall [15] TIRM/STIR, Dixon, spectral fat sat edema, swelling, tumor high signal in TIRM/STIR necrosis, cystic lesions high signal in TIRM/STIR adipose tissue (lipoma, cholesterol granuloma) suppressed signal lymph node metastasis nodal size (minimum axial diameter of 8 -9 mm in level II and 7 -8 mm for the rest of the neck), loss of hilar structure and necrosis (varying level of low-to-high signal intensity on T2w fat sat depending on keratinization, and coagulation and liquefaction necrosis) [18]; lower signal than regular or reactive lymph nodes on inverted TIRM/ STIR [16] extranodal tumor spread nodal size, shaggy margin and flare sign on T2w fat sat [19] SSFP (CISS, FIESTA), SPACE, VISTA, 3D-FLAIR cerebellopontine angles and inner ear (facial and vestibulocochlear nerves, schwannomas)…”

“…Skull base pathologies including various complications from sinonasal and mastoid infections such as orbital cellulitis, orbital abscess, meningitis, epidural and intracranial abscess or thrombosis of venous sinuses are typical MRI indications. Perineural tumor invasion may be diagnosed by the thickening and contrast enhancement of cranial nerves including the presence of skip lesions and dural invasion is best indicated by nodular dural enhancement and a width of enhancement of more than 5 mm [8,9]. The correct staging of head & neck tumors is the basis for recommendations regarding resectability (T4b vs. T4a, surgery vs. radiation therapy), extent of resection (enoral laser vs. transcervical), lymph node dissection (selective vs. modified radical), and many more [10].…”