This clinical trial tests the effect of induction chemotherapy response-guided radiation (de-escalated intensity-modulated radiation therapy \[IMRT\]) compared to standard IMRT in patients with Epstein-Barr virus (EBV)-associated nasopharyngeal cancer. Intensity-modulated radiation therapy (IMRT) is an advanced form of 3-dimensional radiation therapy that uses computer-generated images to show the size and shape of the tumor. Thin beams of radiation of different intensities are aimed at the tumor from many angles. This type of radiation therapy reduces the damage to healthy tissue near the tumor. Radiation therapy sometimes causes unwanted symptoms or side effects, including late effects such as hearing loss and dental problems. The severity of the side effects is related to the radiation dose received and the amount of tissue that received radiation. De-escalation IMRT uses lower doses of radiation based on a good response to induction chemotherapy. Giving de-escalated IMRT may be as effective as standard doses of IMRT in treating patients with EBV-associated nasopharyngeal cancer.
Participants must have histologically or cytologically confirmed (from primary lesion and/or lymph nodes) nasopharyngeal carcinoma.
Participants must have Epstein Barr virus (EBV)-associated nasopharyngeal carcinoma, defined as detectable (> 0 copies/mL) circulating plasma EBV DNA on a qualitative or quantitative polymerase chain reaction (PCR)-based test.
History/physical examination by a medical oncologist or clinical oncologist or radiation oncologist or otolaryngology (ENT);
MRI with contrast of the face, nasopharynx, and neck or CT with contrast of the face, nasopharynx and neck with ≤ 3 mm contiguous slices and bone windows to evaluate base of skull involvement; or
Prior systemic chemotherapy for nasopharyngeal carcinoma, other than induction chemotherapy (IT); note that prior chemotherapy for a different cancer is permitted
Prior radiotherapy to the nasopharynx or surrounding involved areas that would result in overlap of radiation therapy fields
Has participated in a study of an investigational product and received treatment with an investigational drug or used an investigational device within 4 weeks prior to the first dose of treatment
Major medical or psychiatric illness that, in the treating investigator's opinion, would interfere with the completion of therapy and follow-up or interfere with a full understanding of the risks and potential complications of the therapy