Radiation Therapy With or Without Cetuximab in Treating Patients Who Have Undergone Surgery for Locally Advanced Head and Neck Cancer

OBJECTIVES:

Primary

- Determine whether the addition of cetuximab to postoperative intensity-modulated
radiotherapy (IMRT) will improve overall survival (OS) in patients with locally advanced
squamous cell carcinoma of the head and neck at intermediate risk following surgery.

Secondary

- Assess the impact of the addition of cetuximab to postoperative IMRT on disease-free
survival (DFS) of these patients.

- Assess the impact of the addition of cetuximab to postoperative IMRT on acute and late
dysphagia, xerostomia, skin toxicity, and other toxicities according to common Toxicity
Criteria for Adverse Effects (CTCAE), v. 4 and their relationships with patient-reported
outcomes at 3, 12, and 24 months.

- Analyze tumor for epidermal growth factor receptor (EGFR), specifically the extent of
EGFR overexpression by immuno-histochemistry (IHC) and FISH analysis, EGFRvIII
expression, as well as the association of these assay data with OS and DFS.

- Analyze tumor for human papillomavirus (HPV) infection (as defined by in situ
hybridization), specifically, within the cohort of patients with oropharynx cancer, to
perform an exploratory analysis of the impact of HPV on DFS and OS of this patient
subset.

- Analyze tumor DNA for TP53 mutations as a predictor of response to cetuximab and
prognosis.

- Analyze germline DNA of polymorphic variants in EGFR intron repeats as a predictor of
response to cetuximab.

Tertiary

- Assess the impact of the addition of cetuximab to postoperative IMRT on loco-regional
control.

- Assess the impact of the addition of cetuximab to postoperative IMRT on patient-reported
quality of life, swallowing, xerostomia, and skin toxicity based on head and neck
specific instruments, including the Performance Status Scale for Head and Neck Cancer
(PSS-HN), the Functional Assessment of Cancer Therapy-Head & Neck (FACT-H&N), the
University of Michigan Xerostomia-Related Quality of Life Scale (XeQOLS), and the
Dermatology Life Quality Index (DLQI).

- Assess the impact of the addition of cetuximab to postoperative IMRT on cost-utility
analysis using the EuroQol (EQ-5D).

- Evaluate the utility of image-guided radiotherapy (IGRT) as a means of enhancing the
efficacy (i.e., loco-regional control) of IMRT while reducing the acute and/or late
toxicity (particularly xerostomia) and improving patient-reported outcomes (particularly
XeQOLS scores).

- Retrospectively compare the loco-regional control rate in patients treated with IMRT
alone (no IGRT or cetuximab) with similar patients treated with external beam
radiotherapy alone in the postoperative clinical trial Radiation Therapy Oncology Group
(RTOG)-95 01.

OUTLINE: This is a multicenter study. Patients are stratified according to clinical stage
(T2-3 vs T4a), EGFR expression (high [≥ 80% of cells staining positive] vs low [< 80% of
cells staining positive] vs not evaluable), primary site of disease (oral cavity vs larynx vs
oropharynx p16+ vs oropharynx p16- vs oropharynx, p16 not evaluable), and use of image-guided
radiotherapy (yes vs no). Patients are randomized to 1 of 2 treatment arms.

- Arm I: Patients undergo intensity-modulated radiotherapy (IMRT) once daily 5 days a week
for 6 weeks in the absence of disease progression or unacceptable toxicity.

- Arm II: Patients undergo IMRT as in arm I. Patients also receive cetuximab IV over 1-2
hours once weekly beginning at least 5 days prior to the start of IMRT and continuing
for 4 weeks after the completion of IMRT (for a total of 11 doses) in the absence of
disease progression or unacceptable toxicity.

Quality of life is assessed at baseline and at 3, 12, and 24 months.

Tissue samples are collected periodically for further laboratory analysis.

After completion of study treatment, patients are followed up at 1 and 3 months, every 3
months for 2 years, every 6 months for 3 years, and then annually thereafter.

DISEASE CHARACTERISTICS:

- Histologically confirmed squamous cell carcinoma (including variants, such as
verrucous carcinoma, spindle cell carcinoma, or carcinoma not otherwise specified) of
the head and neck, including the following subtypes:

- Oral cavity

- Oropharynx

- Larynx

- Clinical stage T1, N1-2, M0 OR T2-4a, N0-2, M0 disease based on the following
diagnostic workup within the past 8 weeks:

- General history and physical examination by a Radiation Oncologist and/or Medical
Oncologist

- Chest x-ray or chest CT scan (with or without contrast) or chest CT/PET scan
(with or without contrast)

- Must have undergone gross total resection of the primary tumor with curative intent
within the past 7 weeks with surgical pathology demonstrating ≥ 1 of the following
criteria for "intermediate" risk of recurrence:

- Perineural invasion

- Lymphovascular invasion

- Single lymph node > 3 cm or ≥ 2 lymph nodes (all < 6 cm) (no extracapsular
extension)

- Close margin(s) of resection, defined as cancer extending to within 5 mm of a
surgical margin, and/or an initially focally positive margin that is subsequently
superseded by intraoperative negative margins (similarly, patients whose tumors
had focally positive margins in the main specimen but negative margins from
re-excised samples in the region of the positive margin are eligible)

- Pathologically confirmed T3 or T4a primary tumor

- T2 oral cavity cancer with > 5 mm depth of invasion

- No positive margin(s) (defined as tumor present at the cut or inked edge of the
tumor), nodal extracapsular extension, and/or gross residual disease after surgery

PATIENT CHARACTERISTICS:

- Zubrod performance status 0-1

- Absolute granulocyte count ≥ 1,500/mm³

- Platelet count ≥ 100,000/mm³

- Hemoglobin ≥ 8.0 g/dL (transfusion or other intervention allowed)

- Total bilirubin < 2 times upper limit of normal (ULN)

- Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) < 3 times ULN

- Serum creatinine < 2 times ULN OR creatinine clearance ≥ 50 mL/min

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

- No other invasive malignancy within the past 3 years, except for nonmelanomatous skin
cancer or previously treated carcinoma in situ of the breast, oral cavity, or cervix

- No simultaneous primary or bilateral tumors

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

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

- Transmural myocardial infarction within the past 6 months

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

- Chronic obstructive pulmonary disease exacerbation or other respiratory illness
requiring hospitalization or precluding study therapy

- Idiopathic pulmonary fibrosis or other severe interstitial lung disease that
requires oxygen therapy or is thought to have required oxygen therapy within the
past year

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

- AIDS based on current Centers for Disease Control (CDC) definition

- Grade 3-4 electrolyte abnormalities according to CTCAE, v. 4, including any of
the following:

- Serum calcium (ionized or adjusted for albumin) < 7 mg/dL or > 12.5 mg/dL*

- Glucose < 40 mg/dL or > 250 mg/dL

- Magnesium < 0.9 mg/dL or > 3 mg/dL*

- Potassium < 3.0 mmol/L or > 6 mmol/L*

- Sodium < 130 mmol/L or > 155 mmol/L* NOTE: *Despite intervention to
normalize levels.

- No prior allergic reaction to cetuximab

PRIOR CONCURRENT THERAPY:

- See Disease Characteristics

- No prior systemic chemotherapy or anti-epidermal growth factor (EGF) therapy for this
cancer

- Prior chemotherapy or anti-EGF therapy for a different cancer allowed

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

- No concurrent amifostine as a radioprotector

- No concurrent granulocyte colony-stimulating factor or erythropoietin