Prognosis

Evaluation of treatment response

After completing the definitive treatment (definitive radiation therapy, chemoradiation therapy with or without induction, or adjuvant chemotherapy), it is important to document complete remission in the nasopharynx and neck using clinical and endoscopic exam and/or imaging studies.[2]​ The first radiographic assessments are recommended to be done 3 months after treatment completion. Either magnetic resonance imaging (MRI) or with or without contrast positron emission tomography (PET) can be used and both of them are known to have similar sensitivity, although specificity is slightly higher with PET.[2] Plasma Epstein-Barr virus (EBV) DNA can be used as a biomarker to predict prognosis and detect subclinical recurrence, and postradiation therapy clearance of plasma EBV has been shown to be associated with longer progression-free survival in many studies.[2][23]​​​​ A plasma EBV DNA test is usually offered 1-4 weeks after completion of radiation therapy to provide prognostic information. Plasma EBV DNA should be evaluated every year.[2] 

Stage 2 disease with retropharyngeal or ipsilateral cervical nodal metastases (N1) is a heterogeneous category and additional high-risk features have been found to be prognostic for poorer outcomes (node ≥3 cm, “low neck” level IV or VB lymph node, extranodal extension, pretreatment plasma EBV DNA ≥4000 copies/mL).

Evaluate thyroid function annually in patients who have received radiation therapy to the neck and evaluate pituitary function periodically.[2]

Surveillance for recurrence

There is a risk of recurrence, and this peaks at 1.5 years after treatment and again at 3.5 years after treatment.[2] 

Once complete remission is confirmed, the patient should receive periodic clinical and endoscopic exam of the nasopharynx. This should be every 3 months in the first year, every 6 months in the second and third years, then annually for the next 5 years.[2] 

For T2-T4 stage tumors, use MRI with or without contrast to evaluate the nasopharynx and skull base every 6 months for at least the first 3 years after treatment.[2]

Recurrent/metastatic disease

Recurrent/metastatic NPC is not curable and usually leads to fatal outcomes. Median overall survival is about 20 months, based on data prior to widespread use of immune checkpoint inhibitors.[45][46]​ Survival outcome has been improving with advances of novel therapeutics and is expected to keep improving over time.

Use of this content is subject to our disclaimer