Phase III Trial of Radiotherapy Plus Cetuximab Versus Chemoradiotherapy in HPV-Associated Oropharynx Cancer

Inclusion Criteria

DISEASE CHARACTERISTICS:

- Pathologically (histologically or cytologically) proven diagnosis of squamous cell
carcinoma (including the histological variants papillary squamous cell carcinoma and
basaloid squamous cell carcinoma) of the oropharynx (tonsil, base of tongue, soft
palate, or oropharyngeal walls)

- No cancer from an oral cavity site (oral tongue, floor mouth, alveolar ridge,
buccal, or lip), nasopharynx, hypopharynx, or larynx, even if p16 positive

- No carcinoma of the neck of unknown primary site origin (even if p16 positive)

- Cytologic diagnosis from a cervical lymph node is sufficient in the presence of
clinical evidence of a primary tumor in the oropharynx

- Clinical evidence should be documented; may consist of palpation, imaging,
or endoscopic evaluation; and should be sufficient to estimate the size of
the primary (for T stage)

- No distant metastasis or adenopathy below the clavicles

- Patients must be positive for p16, determined by the OSU Innovation Center CLIA lab
prior to step 2 registration (randomization)

- Paraffin-embedded cytology specimens are acceptable for p16 evaluation, but
cytology smears are not

- Patients must have clinically or radiographically evident measurable disease at the
primary site or at nodal stations

- Tonsillectomy or local excision of the primary without removal of nodal disease
is permitted, as is excision removing gross nodal disease but with intact
primary site

- Limited neck dissections retrieving ≤ 4 nodes are permitted and considered as
non-therapeutic nodal excisions

- Fine-needle aspirations of the neck are insufficient due to limited tissue for
retrospective central review

- Biopsy specimens from the primary or nodes measuring at least 3-5 mm are
required

- Clinical stage T1-2 N2a-N3 or T3-4 any N, including no distant metastases

- No clinical stage T1-2 N0-1

- No simultaneous primaries or bilateral tumors

PATIENT CHARACTERISTICS:

- Zubrod performance status 0-1

- ANC ≥ 1,500/mm³

- Platelet count ≥ 100,000/mm³

- Hemoglobin (Hgb) ≥ 8.0 g/dL (transfusion or other intervention to achieve Hgb ≥ 8.0
g/dL is acceptable)

- Bilirubin ≤ 2 mg/dL

- AST or ALT ≤ 3 times upper limit of normal

- Serum creatinine ≤ 1.5 mg/dL OR creatinine clearance ≥ 50 mL/min

- Negative pregnancy test

- Women of childbearing potential and male participants must agree to use a medically
effective means of birth control throughout their participation in the treatment
phase of the study, and until at least 60 days following the last study treatment

- Patients who are HIV-positive and have no prior AIDS-defining illness and have CD4
cells of at least 340/mm³ are eligible

- HIV status must be known prior to registration

- No multidrug resistance for HIV infection

- Not seropositive for hepatitis B (hepatitis B surface antigen positive or
anti-hepatitis B core antigen positive) or hepatitis C (anti-hepatitis C antibody
positive)

- Immunity to hepatitis B (anti-hepatitis B surface antibody positive) allowed

- No prior invasive malignancy except non-melanoma skin cancer, or malignancy for which
the patient has been disease-free for at least 3 years (e.g., carcinoma in situ of
the breast, oral cavity, or cervix)

- No severe, active co-morbidity, defined as any of the following:

- Unstable angina and/or congestive heart failure requiring hospitalization within
the last 6 months

- Acute bacterial or fungal infection requiring intravenous antibiotics at the
time of registration

- Transmural myocardial infarction within the last 6 months

- Chronic obstructive pulmonary disease exacerbation or other respiratory illness
requiring hospitalization or precluding study therapy within 30 days of
registration

- Hepatic insufficiency resulting in clinical jaundice and/or coagulation defects

- Laboratory tests for liver function and coagulation parameters are not
required for entry into this protocol

- Immunocompromised patients

- No prior allergic reaction to cisplatin or cetuximab

PRIOR CONCURRENT THERAPY:

- See Disease Characteristics

- No prior systemic chemotherapy for the study cancer

- Prior chemotherapy for a different cancer allowed

- No prior radiotherapy to the region of the study cancer that would result in overlap
of radiation therapy fields

- No prior cetuximab or other anti-EGFR therapy

- No concurrent amifostine as a radioprotector

- No concurrent granulocyte colony-stimulating factor or erythropoietin