Role of CT and MR examinations in the assessment of nasopharyngeal tumors
Gödény, M.ár.; Lengyel, E.éb.; Polony, I.án.; Esik, O.; Somogyi, A.ás.; Remenár, E.; Németh, G.ör.; Kásler, M.ós.
Orvosi Hetilap 144(42): 2065-2071
2003
ISSN/ISBN: 0030-6002 PMID: 14658418 Document Number: 560823
Tumor staging affects patient prognosis. Significant proportion of the patients with nasopharyngeal malignant tumors have unremarkable clinical symptoms and endoscopic findings, mainly in the early stages. Purpose: The primary role of the imaging modalities is to define the extension, and the stage of tumor. Soft tissue spaces of the neck determine tumor extension. Authors analyzed the routes of tumor extension. Methods: Authors evaluated the routes of extension in 84 nasopharyngeal-tumor-patients with CT and/or MR. More than 5% of the patients presented with asymptomatic enlargement of cervical lymph nodes. Almost 50% of nasopharynx carcinoma-recurrency were endoscopically negative. Results: Imaging modalities found in 76% of patients nodal disease, more than 40% bilateral. Retropharyngeal nodes of Rouvier were commonly affected, in 61% of their cases. The lateral extension, tumor infiltration in the parapharyngeal space was the most common direction, in 69% of our cases. Intracranial extensions were determined in 45% of cases, 30% of nasopharyngeal carcinomas also invaded the skull base. The most common routes of intracranial extension (with or without bone destruction) were via the foramen lacerum and foramen ovale to the cavernous sinus and to the midline cranial fossa, as well as via the carotid channel to the posterior fossa. Cranial nerve involvement occurred in 21%, most commonly V/3, VI, XII were affected. Conclusion: CT/MR provide valuable information regarding the extent of lesion and play key role in the management of epipharynx tumors. MR gives the most information concerning soft tissue infiltration, intracranial extension, perineural-, bone marrow involvement, recurrent disease. MR is less useful than CT for the detection of cortical bone erosion. Skull base involvement, cranial nerve infiltration upgrades the staging to T4, alters the therapy (may indicate adjuvant chemotherapy in addition to radiotherapy) and also alters the field of the radiation therapy. CT and MR scans can be used directly in the radiotherapy planning process.