What pre-surgical workup is needed for an adult patient with newly diagnosed tonsillar cancer, possibly with a history of smoking or alcohol use, and taking metformin, before undergoing surgery for head and neck cancer?

Pre-Surgical Workup for Tonsillar Cancer Beyond CT Chest with Contrast

For a patient with newly diagnosed tonsillar cancer undergoing CT chest with contrast for staging, the head and neck surgeon requires: complete head and neck examination with flexible nasendoscopy, tissue diagnosis with HPV testing, assessment of vocal cord mobility, dental evaluation, nutritional assessment, and metformin management if applicable.

Essential Clinical Evaluation

Complete Head and Neck Examination

• Perform flexible nasendoscopy to visualize the larynx, base of tongue, and pharynx, as this is essential for patients with neck masses at increased risk for malignancy 1
• Assess vocal cord mobility to evaluate for laryngeal nerve involvement 1
• Conduct visual and digital examination of the oral cavity, including ventral and lateral surfaces of the tongue and floor of mouth 1
• Evaluate cranial nerve function systematically, including ocular motility, facial sensation and movement, hearing, palate elevation, gag reflex, and tongue mobility 1
• Examine skin and scalp for cutaneous malignancies 1

Tissue Diagnosis and HPV Status

• Obtain tissue diagnosis through biopsy of the primary site or fine-needle aspiration/core-needle biopsy of cervical lymph nodes 1
• Test all specimens for high-risk HPV using p16 immunohistochemistry as the surrogate marker, with strong and diffuse nuclear and cytoplasmic staining in at least 70% of tumor cells indicating HPV-positive status 1
• Consider additional HPV-specific testing (DNA in situ hybridization or PCR) if p16 results are equivocal, as discordance rates between p16 and HPV-specific testing range from 4-20% 1

Risk Factor Documentation

Tobacco and Alcohol History

• Document detailed tobacco use history, including current status, pack-years, and duration, as tobacco and alcohol are responsible for 75-85% of head and neck squamous cell carcinomas 2
• Quantify alcohol consumption specifically, as more than two drinks per day substantially increases oral cavity cancer risk, with beer consumption showing particularly strong associations (OR 3.8 for ≥15 beers/week) 2
• Consider panendoscopy to evaluate for synchronous tumors in patients with prolonged alcohol and tobacco use history 2

Imaging Studies

Neck and Chest Imaging

• CT chest with contrast is already ordered for staging and to evaluate for distant metastases 1
• Neck ultrasound is recommended for preoperative evaluation 1
• Consider PET-CT for stage III/IV disease, as it may alter management by upstaging patients 1
• PET-CT should ideally be obtained before any pleurodesis procedures, as talc causes pleural inflammation affecting FDG avidity 1

Specialized Assessments

Dental Evaluation

• Obtain comprehensive dental evaluation including Panorex imaging to assess mandibular involvement, which is particularly important for oral cavity and tonsillar cancers 1
• Dental rehabilitation is essential before radiotherapy to prevent osteoradionecrosis 3

Nutritional Assessment

• Assess nutritional status, with patients having more than 10% weight loss in 6 months requiring enteral feeding before treatment 3
• Consider percutaneous gastrostomy over nasogastric tube for anticipated long-term nutritional support 3

Metformin Management

Pre-operative Medication Considerations

• Review metformin use in the context of surgery, though current evidence shows metformin may have anticancer effects on head and neck squamous cell carcinoma through global inhibition of protein translation 4
• Standard perioperative metformin management protocols should be followed, typically holding metformin 24-48 hours before surgery due to contrast administration and surgical stress
• Coordinate with anesthesia regarding timing of metformin discontinuation

Contralateral Tonsil Evaluation

Bilateral Disease Assessment

• Plan for contralateral tonsillectomy during primary transoral robotic surgery, as 10% of patients with tonsillar cancer have contralateral disease not identified on preoperative PET-CT or clinical examination 5
• Contralateral tonsillectomy adds minimal morbidity (only 11.5 cc additional blood loss) with no differences in complications, gastrostomy tube rates, or length of stay 5

Pre-operative Laboratory Testing

Essential Laboratory Work

• Check platelet count, prothrombin time, and partial thromboplastin time for patients undergoing biopsy or surgery 6
• Routine preoperative checks are only required for patients with known risk factors 6

Smoking Cessation

Pre-operative Optimization

• Initiate smoking cessation as far in advance as feasible, though patient smoking should not delay appropriate timing for cancer resection 1
• Combine pharmacotherapy (combination NRT or varenicline) with behavioral counseling for optimal results 1
• Note that NRT at normal doses does not negatively affect acute wound healing 1

Common Pitfalls to Avoid

• Do not proceed without HPV testing, as this fundamentally alters prognosis and may influence treatment decisions 1
• Do not skip contralateral tonsil evaluation, as bilateral disease occurs in 10% of cases and is not reliably detected on imaging 5
• Do not delay surgery for smoking cessation, though cessation should be encouraged and supported 1
• Do not overlook nutritional status, as significant weight loss requires intervention before treatment 3
• Do not forget dental evaluation, as this prevents serious complications from subsequent radiotherapy 1, 3